CN2874782Y - Battery module - Google Patents

Abstract

The utility model discloses an assembled battery, in which a plurality of flat batteries are stacked, and each flat battery is formed by encapsulating an electric generating element with a package and leading out a plate-shaped electrode joint from the package, and the electrodes of the flat battery The terminals are electrically connected to each other. The assembled battery includes a plate-shaped electrically insulating spacer adapted to sandwich the electrode tab from opposite surface sides of the electrode tab along a stacking direction of the plurality of flat batteries. The spacers arranged in pairs sandwiching the electrode tabs include engagement members adapted to fix the electrode tabs by passing through the electrode tabs in a stacking direction.

Description

Assembled battery

technical field

The utility model relates to a battery, in particular to an assembled battery formed by stacking a plurality of flat batteries.

Background technique

There is known a flat thin battery (hereinafter referred to as "flat battery") formed by encapsulating an electricity generating element with a package such as a laminated film and drawing out plate-like electrode terminals from the package (hereinafter referred to as "flat battery"), wherein the electricity generating element The element is formed by laminating positive and negative electrode plates. In recent years, it has become fashionable to produce a high-output and high-capacity assembled battery by stacking a plurality of such flat batteries while electrically connecting the individual flat batteries in series and/or parallel (refer to Unexamined Japanese Patent Publication JP -A-200-195480 and JP-A-2001-256934).

For example, in order to mount the assembled battery thus formed on a vehicle, efforts have been made to minimize the distance between adjacent flat batteries to compress the entire volume of the assembled battery and to give the assembled battery a structure less affected by vibration input. The need for it is generally recognized. When vibration is applied to be borne by the assembled battery, stress concentration may be caused on the portion for connecting the electrode tabs to each other.

Utility model content

An object of the present invention is to provide an assembled battery which is only slightly affected by vibration input and which can promote compactness in volume.

The combined battery of the present utility model comprises:

A plurality of flat batteries, each of which is provided with a package for encapsulating an electric generating element and an electrode joint leading from the package to the outside, the plurality of flat batteries are stacked and adjacent to each other along the stacking direction the electrode terminals of the flat cells are electrically connected to each other, and

An insulating plate sandwiching the electrode tab from opposite surface sides of the electrode tab along a stacking direction of the plurality of flat batteries and having an electrical insulating property.

Preferably, one of the pair of insulating plates clamping the electrode joint is used to clamp the other electrode joint at the same time.

Preferably, the insulating plates are connected to each other.

Preferably, the pair of insulating plates sandwiching the electrode joints is provided with an engaging piece adapted to fix the electrode joints by passing through the electrode joints in a stacking direction.

Preferably, the electrode joints are provided with through-holes along the stacking direction, and the joints are provided with protrusions and recesses, the protrusions being adapted to be inserted into the insulating plates provided in the paired arrangement In a through hole on one of the paired insulating plates, the concave portion is adapted to allow insertion therein of a front end of a protruding portion provided on the other of the paired insulating plates and inserted into the through hole.

Preferably, the insulating plates are respectively provided with a protrusion and a recess, the protrusion being provided on one of the opposite surfaces along the stacking direction, and the recess being provided in the opposite surface along the stacking direction The other one, and the protruding portion and the concave portion are arranged on the same straight line along the stacking direction.

Preferably, the insulating plates are respectively provided with notches for exposing part of the periphery of the clamped electrode joints, and the area of the electrode joints exposed through the notches is used as a voltage for detecting the voltage of each of the flat cells detection department.

Preferably, the assembled battery further includes a connector provided with a connection terminal connectable to the voltage detection part and detachably attached to the voltage detection part.

Preferably, the plurality of voltage detection parts are arranged on the same straight line along the stacking direction, and the connector is provided with a plurality of connection terminals corresponding to the positions of the respective voltage detection parts.

Preferably, the voltage detection part is provided with a voltage detection wiring board stacked and connected to the electrode connectors.

Preferably, the electrode joints stacked and clamped on the electrode joint provided with the voltage detection wiring board are provided with a notch for receiving the voltage detection wiring board.

Preferably, the electrode joints are connected to each other by ultrasonic welding, and the electrode joints and the voltage detection wiring board are connected by stamping or using rivets.

Preferably, the electrode joint and the voltage detection wiring board are connected by stamping or using a rivet with a head, and each insulating plate is provided with a concave portion, which allows to be formed on the The protrusions on the surface of the voltage detection terminal board or the heads of the rivets on the surface of the voltage detection terminal board are inserted thereinto.

Preferably, the insulating plate is provided with an opening window formed through the stacking direction, and the plurality of electrode contacts are stacked, close to the opening window, and sandwiched by the pair of insulating plates, and The plurality of flat cells are electrically connected by interconnecting electrode tabs near the opening window.

Preferably, the electrode joints are clamped by insulating plates, and a part of the electrode joints is close to the outer sides of the paired insulating plates, and the plurality of flat batteries are connected to each other by interconnecting the electrodes close to the outer sides of the insulating plates connector for electrical connection.

Preferably, the assembled battery further includes positive and negative assembled battery output terminals, and wherein the insulating plate is provided with an opening window formed through in a stacking direction, and the electrode joint and one of the assembled battery output terminals are stacked set, close to the opening window, and clamped by the pair of insulating plates, and each of the assembled battery output terminals is electrically connected by connecting the electrode joint close to the opening window and the assembled battery output terminal. connected to the flat battery.

Preferably, a plurality of stacked flat batteries are connected in series by electrically connecting electrode contacts with different polarities, and the output terminal of the positive assembled battery and the output terminal of the negative assembled battery are electrically connected to two opposite ends along the stacking direction. battery.

Preferably, the insulating board is provided with an insulating layer having electrical insulating properties and a heat dissipation layer having higher thermal radiation properties than the insulating layer.

Preferably, the plurality of electrode joints are stacked, their ends are close to the outer side of the insulating plate, and are sandwiched by the pair of insulating plates, and the plurality of flat batteries are connected to each other close to the The ends of the electrode tabs on the outer side of the insulating plate are electrically connected.

Preferably, the assembled battery further includes a case for fixing a position of the separator and accommodating a plurality of flat batteries.

By adopting the technical solution of the utility model, the distance between the batteries can be reduced to the greatest extent, so that the compactness of the whole assembled battery can be realized. Also, by sandwiching the electrode tabs from the opposite surface sides of the electrode tabs in the stacking direction of the plurality of flat batteries by an insulating plate having an electrical insulating property, the assembled battery exhibits increased shock resistance, showing Insensitivity to vibration input effects.

Objects, features and characteristics of the present invention in addition to those set forth above will become apparent from the following description given in conjunction with preferred embodiments shown in the accompanying drawings.

Description of drawings

FIG. 1 is a perspective view illustrating an assembled battery according to a first embodiment of the present invention;

Fig. 2 is a perspective view illustrating the assembled battery shown in Fig. 1 in a vertically inverted and disassembled state;

Fig. 3 is a plan view illustrating a battery cell contained in a case;

Figure 4 is a cross-sectional view taken along line 4-4 in Figure 3;

Figure 5 is a cross-sectional view taken along line 5-5 in Figure 3;

6 is a perspective view illustrating a battery cell exposed by detaching an insulating cover from a battery cell main body;

FIG. 7 is a perspective view illustrating the same battery cell viewed from a direction different from that of FIG. 6;

8 is a perspective view illustrating the same battery cell viewed from the bottom side;

9 is a perspective view illustrating the main body of the battery unit;

10 is a perspective view illustrating three subassemblies forming a battery cell main body with its front surface side on the front side;

Figure 11 is a perspective view illustrating a subassembly with its rear surface side pointing forward;

Figure 12 is a perspective view illustrating these subassemblies viewed from the bottom surface side;

Fig. 13 is an exploded perspective view illustrating the main body of the battery unit with the front surface side facing forward;

14 is an exploded perspective view illustrating the main body of the battery unit with the rear surface side facing forward;

Fig. 15 is a conceptual diagram for helping to explain the stacked state of the flat battery and the insulating plate in the battery cell main body;

Fig. 16 is a conceptual diagram to help explain the electrical connection state of each flat battery in the battery unit body;

17 is a perspective view illustrating an example of a flat battery contained in a battery cell main body;

18A is a perspective view illustrating an example of an insulating plate included in the battery cell main body; FIG. 18B is a perspective view illustrating the same insulating plate in a state where the front and rear surfaces are reversed; and FIG. 18C is along A sectional view taken along line 18C-18C in 18A;

19A and 19B are perspective views to help explain a state where an electrode terminal and an output terminal of an assembled battery are stacked and held by a pair of insulating plates;

20A and 20B are perspective views to help explain the state in which the electrode tabs of the flat batteries stacked on the lower position side in the view of FIG. 19A are further clamped;

Fig. 21A, Fig. 21B and Fig. 21C are perspective views, which are used to help explain the state that a plurality of electrode joints are stacked and clamped by a pair of insulating plates;

22A is a perspective view illustrating a voltage detection portion on the front surface side of the battery cell body; and FIG. 22B is a perspective view illustrating a state in which a connector is inserted into an insulating cover attached to the front surface of the battery cell body;

23A is a perspective view illustrating a state in which the connector has been pulled out from the state of FIG. 22B; FIG. 23B is a perspective view illustrating an insulating cover; and FIG. 23C is a perspective view illustrating the connector;

Fig. 24A is a plan view illustrating the main part of a flat battery having a voltage detection terminal plate connected overlying on electrode contacts; Fig. 24B is a sectional view taken along line 24B-24B in Fig. 24A showing electrode contacts and The voltage detection wiring board is connected by stamping and pressing; and Fig. 24C is a sectional view of the main part, illustrating the way of inserting the connector into the voltage detection part;

25A is a sectional view illustrating a main part of an insulating plate provided with a recess for receiving a protrusion formed on the surface of a voltage detection wiring board by punching; and FIG. 25B is a sectional view illustrating The status of the connection between the electrode connector and the voltage detection terminal board through rivets;

Fig. 26 is a view used to help explain the assembly process of the first subassembly;

Figure 27 is a view following Figure 26;

Figure 28 is a view following Figure 27;

Figure 29 is a view following Figure 28;

Figure 30 is a view following Figure 29;

Figure 31 is a view following Figure 30;

Fig. 32 is a view used to help explain the assembly process of the second subassembly;

Figure 33 is a view following Figure 32;

Fig. 34 is a view used to help explain the assembling process of the third subassembly;

Figure 35 is a view following Figure 34;

Figure 36 is a view following Figure 35;

Figure 37 is a view following Figure 36;

Figure 38 is a view following Figure 37;

Figure 39 is a view following Figure 38;

40 is a sectional view illustrating an assembled battery according to a second embodiment of the present invention;

Figure 41 is a perspective view illustrating a flat battery;

Fig. 42 is a plan view illustrating a main part of a state in which electrode tabs are held mutually by insulating plates;

Fig. 43 is a cross-sectional view illustrating the manner in which flat cells are stacked;

Figure 44 is a cross-sectional view illustrating the stacking of flat batteries that have been stacked;

45 is a cross-sectional view illustrating the manner in which the ends of stacked electrode joints are connected to each other by tungsten inert gas welding (TIG welding);

Fig. 46 is a view illustrating the manner in which the ends of stacked electrode tabs are connected to each other by laser welding;

Fig. 47 is a view illustrating the manner in which the ends of stacked electrode joints are connected to each other by friction stir welding (friction agitation bonding);

Fig. 48 is a view illustrating the manner in which flat batteries are stacked in a third embodiment according to the present invention;

Figure 49 is a cross-sectional view taken along line 49-49 in Figure 48; and

Fig. 50 is a sectional view illustrating the assembled battery of the third embodiment.

Detailed ways

Now, embodiments of the present invention will be described with reference to the accompanying drawings.

(first embodiment)

The direction of the X-axis shown in FIG. 1 will be referred to as the longer direction of the assembled battery 50, the battery unit 60, the case 70, etc., and the direction of the Y-axis will be referred to as the shorter direction thereof. Therefore, the surface located on the front side in the longer direction in FIG. 1 is referred to as the front surface, and the surface located on the rear side in the longer direction is referred to as the rear surface. In the following description, the flat battery is simply abbreviated as "battery".

Referring to FIGS. 1 and 2 , assembled battery 50 contains within housing 70 a battery cell 60 containing a plurality (eight in the example) of batteries 100 (generally 101-108). The assembled battery 50 is mounted on a vehicle such as, for example, an automobile or an electric train that generates vibration transmitted to the battery unit 60 . Although not shown, an on-vehicle battery pack conforming to required current, voltage, and capacity can be formed by stacking an arbitrary number of assembled batteries 50 and connecting the individual assembled batteries in a series-parallel connection. When connecting the assembled batteries 50 in a series-parallel connection, an appropriate connection member such as a bus bar is used. The assembled battery 50 is cooled with air during use. The plurality of assembled batteries 50 are stacked with a space apart by intervening flanges, and each space serves as a cooling air passage through which cooling air flows and cools each assembled battery 50 . By passing the cooling air and cooling the individual assembled batteries 50, the battery temperature can be reduced and deterioration of characteristics such as charging efficiency can be suppressed.

The above-mentioned case 70 includes a lower case 71 shaped like a box in which an opening 71a is formed, and an upper case 72 constituting a cover member for closing the opening 71a. The edge portion 72a of the upper case 72 is rolled around the edge portion 71c of the peripheral wall 71b of the lower case 71 by hemming (refer to a partially enlarged portion of FIG. 1 ). The lower case 71 and the upper case 72 are formed of a thin-walled steel plate or aluminum plate, and each is formed into a prescribed shape by press working.

As shown in FIGS. 3-9 , the above-mentioned battery unit 60 includes a battery unit body 80 and insulating covers 91 and 92 detachably installed on the front surface and the rear surface of the battery unit body 80, and the battery unit body 80 is stacked. Eight batteries 100 are formed by connecting each battery 100 in series.

The battery cell main body 80 also includes a spacer 110 (corresponding to an insulating plate) for sandwiching the electrode tab 100t and the positive and negative output terminals 140, 150 (corresponding to the output terminals of the assembled battery). Here, the electrode tabs 100t are collectively referred to as a positive electrode tab 100p and a negative electrode tab 100m. The positive electrode tab 100p generally refers to the positive electrode tabs 101p, 102p, 103p, 104p, 105p, 106p, 107p, and 108p corresponding to the batteries 101-108, and the negative electrode tab 100m generally refers to the negative electrode tabs corresponding to the respective batteries 101-108. 101m, 102m, 103m, 104m, 105m, 106m, 107m and 108m. The spacer 110 generally refers to the spacers 121-138.

The insulating covers 91 and 92 serve to cover the front surface side and the rear surface side of the battery cell main body 80 . The insulating covers 91 and 92 are respectively provided at central positions thereof with insertion holes 91a, 92a for fitting a connector 170 (refer to FIG. 23 ) which will be described in detail below. The connector 170 is connected to the voltage detection part 160 for detecting the voltage of the battery 100 (refer to FIG. 6 , FIG. 7 and FIG. 9 ). The purpose of performing voltage detection is to manage charging and discharging of each assembled battery 50 . The insulating covers 91, 92 are provided on their insides with guide plates 91b, 92b for guiding the insertion and extraction of the connector 170, and on their peripheries are provided with a plurality of snap-fit claws 91c, 92c. 91c, 92c are used to immobilize the insulating covers 91, 92 by engaging with the spacer 110 and the output terminals 140, 150 (refer to FIGS. 6-8 ).

Referring again to FIGS. 1 and 2 , the positive and negative output terminals 140 , 150 are drawn out through the housing 70 through cutout portions 71 d , 71 e formed on a portion of the peripheral wall 71 b of the lower housing 71 . The insertion holes 91a, 92a of the insulating covers 91, 92 are similarly passed through a cutout portion 71f formed on a part of the peripheral wall 71b and exposed to the outside of the housing 70. In order to insert through bolts (not shown) at the four corners of the housing 70, bolt holes 73 are formed at the four corners of the lower housing 71 and the upper housing 72, while each spacer 110 Bolt holes 111 are formed at the two parts of the . Reference numeral 93 in FIG. 2 denotes a bushing to be inserted into the bolt hole 111 of the spacer 110 , and reference numeral 94 denotes a buffer to be placed between the battery cell 60 and the upper case 72 .

The case 70 fixes the position of the separator 110 and contains a plurality of batteries 100 . The position of the spacer 110 is fixed relative to the case 70 by inserting through bolts through the bolt holes 73 of the lower case 71 and the upper case 72 and through the sleeves 93 inserted in the bolt holes 111 of the spacer 110 . Since the position of the separator 110 is fixed, the positions of the plurality of batteries 100 are fixed relative to the case 70 because the separator 110 sandwiches the electrode tab 110t.

Referring to FIGS. 10-12 , the battery unit body 80 is formed by assembling first to third three subassemblies 81 , 82 and 83 . In FIG. 10 , the first subassembly 81 shown in the uppermost position is formed by stacking three cells 101 , 102 and 103 thereon and connecting these cells 101 , 102 and 103 in series connection. The second subassembly 82 shown in the middle is formed by stacking two cells 104 and 105 thereon and connecting these cells 104 and 105 in a series connection. The third subassembly 83 , shown in the lowermost position, is formed by stacking three cells 106 , 107 and 108 thereon and connecting these cells 106 , 107 and 108 in a series connection. The first subassembly 81 has a negative output terminal 150 provided thereon, while the third subassembly 83 has a positive output terminal 140 provided thereon. The first subassembly 81 and the second subassembly 82 are electrically connected by interconnecting the electrode joints 103p and 104m facing the outside of the spacer 110 on the rear surface side; The electrode tabs 105p and 106m on the outside of 110 are interconnected and likewise electrically connect the second subassembly 82 and the third subassembly 83 . The opposite surfaces of the battery 103 of the first subassembly 81 and the battery 104 of the second subassembly and the opposite surfaces of the battery 105 of the second subassembly 82 and the battery 106 of the third subassembly 83 are bonded by double-sided coated tapes, respectively.

The right side of FIG. 15 constitutes the front surface side, and the left side thereof constitutes the rear surface side. 13-15, the battery unit body 80 includes 8 batteries 101-108, 18 spacers 121-138 and two output terminals 140 and 150. The 18 spacers 121-138 are arranged in half, on the front surface side and nine each on the rear surface side. For the convenience of description, the eight batteries 101-108 are sequentially referred to as the first battery 101-the eighth battery 108 from top to bottom along the battery stacking direction (vertical direction in FIG. 15). The nine spacers 121 - 129 on the front surface side are called first spacer 121 - ninth spacer 129 sequentially from top to bottom along the battery stacking direction. Likewise, the nine spacers 130 - 138 on the rear surface side are called tenth spacers 130 - eighteenth spacers 138 .

The first-eighteenth separators 121-138 are arranged so as to sandwich the electrode tab 100t from opposite surface sides of the electrode tab 100t along the stacking direction of the batteries. The positive output terminal 140 includes a plate-like bus bar 141 stacked on the positive electrode tab 108p of the eighth battery 108 and a resinous cover 142 for covering electrodes provided on the terminal portion of the bus bar 141 . The negative output terminal 150 includes a plate-shaped bus bar 151 stacked on the negative electrode tab 101m of the first battery 101 and a resinous cover 152 for covering electrodes provided on the terminal portion of the bus bar 151 . Both bus bars 141 and 151 are formed of copper plates. The electrodes of the positive output terminal 140 and the resin cover 142 are located on the right terminal portion of the terminal portions on both sides of the bus bar 141 when viewed from the front side. On the contrary, the electrode of the negative output terminal 150 and the resinous cover 152 are located on the left terminal portion of the bus bar 151 . Incidentally, among the opposing surfaces of the electrode tab 100t and the separator 110 along the cell stacking direction, the upper side surface in FIG. 15 will be referred to as the front, and the lower side surface will be referred to as the rear. The bus bars 141 and 151 respectively have a pair of through holes 143 and 153 extending from the front to the rear along the stacking direction.

FIG. 17 illustrates a first battery 101 as an example of the battery 100 . In FIG. 16 , the right side constitutes the front surface side, and the left side constitutes the rear surface side. Referring to FIGS. 16 and 17, the battery 100 is a flat lithium ion secondary battery having a package 100a such as a sealed laminated film; a stacked type electricity generating element (not shown), and the electricity generating element is stacked sequentially by positive Electrode plates, negative electrode plates and separators are formed. In the battery 100, the plate-shaped electrode tab 100t whose end is electrically connected to the electricity generating element is led out from the package 100a toward the outside, and the positive electrode tab 100p and the negative electrode tab 100m face the opposite side of the battery 100 in the longer direction (front Surface side and rear surface side) protrude. In the case of the battery 100 provided with stacked type electricity generating elements, in order to maintain a uniform distance between adjacent electrode plates and maintain battery performance, the electricity generating elements need to be compacted with pressure. Thus, each battery 100 is contained in the case 70 so that the electricity generating element is compacted.

In FIG. 17 , reference numeral 161 denotes a terminal plate (corresponding to a voltage detection terminal plate) stacked and bonded to the negative electrode tab 100m, and reference numeral 162 denotes a pair of through holes formed on the terminal plate 161 . In the negative electrode tab 100m, a pair of through holes 109 communicating with the through holes 162 of the terminal plate 161 are formed (refer to FIG. 24B ). The positive electrode tab 100p may optionally have a through hole 109 formed thereon. Specifically, the positive electrode tabs 102p, 103p, 105p, 106p, and 108p of the second, third, fifth, sixth, and eighth batteries 102, 103, 105, 106, and 108 respectively have through holes 109 (refer to FIGS. Figure 14). The through holes 109 and 162 extend from the front to the rear along the stacking direction.

FIG. 18A illustrates fourth, sixth, twelfth, fourteenth, and sixteenth spacers 124 , 126 , 132 , 134 , and 136 as one example of spacer 110 . 19A and 19B illustrate a state where the negative electrode tab 101m and the negative output terminal 150 of the battery 101 are sandwiched by a pair of spacers 121 and 122 stacked. 20A and 20B illustrate a state in which the positive electrode tab 102p of the battery 102 stacked on the lower position side in the diagram of FIG. 19A is further clamped. 21A , 21B and 21C illustrate a state where a plurality of electrode tabs 101 p and 102 m are stacked and held by a pair of spacers 131 and 132 .

Referring to FIG. 18 , the separator 110 is formed in a plate shape for sandwiching the electrode tab 100t from opposite surface sides of the electrode tab 100t along the stacking direction of the plurality of batteries 100 , and the separator 110 is given an electrical insulating property.

The material of the spacer 110 is not particularly limited, but only needs to have electrical insulating properties and be imparted with sufficient strength to hold the electrode tab 100t. For example, an electrically insulating resin-based material may be used. On opposite end portions along the longer direction of the spacer 110 , there are formed bolt holes 111 extending from the front to the rear for allowing insertion of the sleeve 93 (refer to FIG. 2 ). By sandwiching the electrode tab 100t by the separator 110, it is possible to suppress vibration of the electrode tab 100t and prevent stress concentration on the electrode tab 100t when the assembled battery 50 is subjected to vibration. As a result, the durability of the electrode tab 100t and thus the durability of the assembled battery 50 can be improved. In addition, since the electrode tabs 100t are sandwiched by the separator 110 having an electrical insulating property, even when the distance between the batteries 100, that is, the distance between the electrode tabs 100t is reduced, the electrode tabs 100t are prevented from forming each other. short circuit. As a result, the necessary space compactness can be given to the assembled battery 50 as a whole by reducing the distance between the batteries to the greatest extent possible. Therefore, it is possible to provide the assembled battery 50 which exhibits increased shock resistance, exhibits insensitivity to the influence of vibration input, and allows compactness in size. In addition, since the battery cell main body 80 has the spacers 110 provided on opposite ends along the battery stacking direction, it can reduce the exposure of the electrode tab 100t and can facilitate the battery cell main body 80 during assembly of the assembled battery 50. disposal. Incidentally, the insulating covers 91 and 92 are formed of the same material as the spacer 110 .

In the spacer 110, an opening window portion 112 extending from the front to the rear in the stacking direction is formed. In the example, rectangular opening windows 112 are formed at two portions equally spaced from the center toward both sides along the longer direction of the spacer 110 . The opening window portion 112 faces a part of the clamped electrode tab 110t (refer to FIG. 19B and FIG. 21C ).

The spacer 110 is also provided with a pin 113 (corresponding to the protrusion) on the front face which is one of the opposing surfaces in the stacking direction, and is provided on a rear face which is the other of the opposing surfaces in the stacking direction There is a recess 114 . These pins 113 and recesses 114 are arranged in a line along the stacking direction (refer to FIG. 18C ). In the example, a pair of pins 113 and a pair of recessed portions 114 are provided from the opening window portion 112 toward the center in the longer direction of the spacer 110 . Incidentally, the pin 113 may alternatively be called a protrusion.

One of the paired spacers holding the electrode tab simultaneously serves as one of the paired spacers holding the other electrode tab. For example, as shown in FIG. 15, the negative electrode tab 101m of the first battery 101 is clamped by the paired first and second separators 121 and 122, while the positive electrode tab 102p of the second battery 102 is sandwiched by the paired first and second separators. The second and third spacers 122 and 123 are clamped. In this example, the second separator 122 is used to hold the negative electrode tab 101m and at the same time hold the positive electrode tab 102p. By simultaneously using the separator 122 as described above, it becomes possible to reduce the distance between the negative electrode tab 101m on the upper position side and the positive electrode tab 102p on the lower position side. Thus, by reducing the distance between the batteries 100 as much as possible, it becomes possible to realize the compactness of the entire assembled battery 50 .

As also shown in FIGS. 19A and 19B , engaging holes 115 extending from the front to the rear are formed on the spacer 122 on the lower position side, and snap-fit claws 116 are protrudingly formed on the spacer on the upper position side 121 on the back. The snap-fit claws 116 are inserted into the engaging holes 115 of the spacer 122 provided on the rear surface, and are thus engaged with the spacer 122 . That is, the spacers 110 are combined by being inserted into each other. As a result, the interconnection of the spacers 110 can be easily and quickly realized, and the work of clamping the electrode tab 110t can be easily and quickly realized.

Referring now to FIGS. 19-21 , the pair of spacers clamping the electrode tab 100t is provided with an engagement member 117 for passing through the electrode tab 100t and engaging the electrode tab 100t. Specifically, as shown in FIG. 19, the negative electrode tab 101m is formed thereon with a through hole 109 penetrating in the stacking direction, and the engaging member 117 is provided with a pin 113 and a recessed portion 114, the pin 113 being formed in a pair of One spacer 122 of the spacers 121, 122 is inserted into the through hole 109, while the recess 114 is provided on the other spacer 121 of the pair of spacers 121, 122 and allows the insertion of the pin 113 of the through hole 109. Front insert insert. Due to the above-mentioned engaging member 117, a possible positional deviation of the spacers 121 and 122 relative to the negative electrode tab 101m can be eliminated, and thus it is possible to prevent possible formation of a gap between the electrode joints due to the above-mentioned deviation when the assembled battery is subjected to the influence of vibration. short circuit.

Here, the spacer 110 is provided with a pin 113 on its front face and a recessed portion 114 on its rear face, the pins 113 and the recessed portion 114 being arranged on the same straight line along the stacking direction (refer to FIG. 18C ). When the electrode tab 100t on which the through hole 109 is formed is clamped by the spacer 110 configured as described above, the engagement member 117 is configured as described above, which can eliminate possible positional deviation of the spacer 110 relative to the electrode tab 100t, and thus A short circuit that may be formed between the electrode tabs 100t due to the above deviation can be prevented when the assembled battery is subjected to the influence of vibration. Furthermore, when a plurality of batteries 100 are stacked to form the assembled battery 50, by inserting the front ends of the pins 113 of the spacers 110 on the side of the lower position into the recesses 114 of the spacers 110 on the side of the upper position, the spacers can be fixed at the same time. The position of the member 110 relative to the electrode joint 100t and the mutual position of the respective batteries 100 . By causing the pin 113 and the recessed portion 114 to exhibit the positioning action as described above, the operability of the assembled battery 50 during assembly can be improved.

Since bus bars 141 and 151, terminal block 161, and electrode tab 100t each have through holes 143, 153, 162, and 109 formed at two points, they can be prevented from freely rotating by inserting pin 113 into the through holes. Preferably, one of each pair of through holes 143, 153, 162 and 109 is formed in a circular shape, and the remaining one is formed in an elliptical shape. The reason why these two shapes are used for the through hole is that the insertion of the pin 113 can be easily achieved.

Referring to FIG. 19, the negative electrode tab 101m and the bus bar 151 of the negative output terminal 150 are superimposed, and a part of the negative electrode tab 101m and a part of the bus bar 151 are sandwiched by the pair of spacers 121 and 122 near the opening window 112, The spacers 121 and 122 are provided with the opening window portion 112 extending in the stacking direction. The output terminal 150 is electrically connected to the first battery 101 by connecting the negative electrode tab 101 m near the opening window portion 112 with the bus bar 151 . When the connection of the negative electrode tab 101m and the bus bar 151 is performed by welding, the negative electrode tab 101m and the bus bar 151 can be kept in a stacked state, and in addition, by using both the spacers 121 and 122 as jigs, the welding can be easily performed. The head is positioned in the opening window 112 . As a result, welding can be performed through the opening window portion 112, and the workability of welding can be improved. By inserting the pin 113 of the second spacer 122 through the bus bar 151, the negative electrode terminal 101m of the first battery 101 and the through holes 153, 109 and 162 of the terminal block 161 and pushing it into the recess 114 of the first spacer 121 In this process, the positioning of the bus bar 151, the negative electrode terminal 101m of the first battery 101 and the terminal block 161 is realized. The outer peripheries of the negative electrode tab 101 m and the bus bar 151 are insulated by spacers 121 and 122 except for the portion facing the opening window portion 112 and the portion constituting the voltage detection portion 160 .

Referring to FIG. 20 , a pair of separators 122 and 123 sandwich a positive electrode tab 102p, and a portion of the positive electrode tab 102p is close to the outside of the separators 122 and 123 . The positive electrode tab 102p of the second battery 102 is positioned by passing the pin 113 of the third separator 123 through the through hole 109 of the second battery 102 and pushing the pin 113 into the recess 114 of the second separator 122 . Incidentally, the positive electrode tab 102p near the outer side of the separators 122 and 123 is connected to the negative electrode tab 103m near the outer side of the separators 123 and 124, so that the second battery 102 and the third battery 103 are electrically connected (refer to FIG. 15 ).

Referring to Fig. 21, a plurality of electrode joints 101p and 102m are stacked, and clamped by a pair of spacers 131 and 132, the spacers 131 and 132 are provided with opening windows 112 penetrating along the stacking direction, and the electrode joints 101p and 102m are partially close to the opening window portion 112 . Then, the plurality of batteries 101 and 102 are electrically connected by interconnecting the electrode tabs 101p and 102m facing the opening window portion 112 by ultrasonic welding. When the electrode tabs 101p and 102m are connected to each other by welding, the electrode tabs 101p and 102m can be kept in a state of being superimposed on each other, and in addition, by using both the spacers 131 and 132 as jigs, the welding of the welding equipment can be easily performed. The head is positioned in the opening window 112 . As a result, welding can be performed through the opening window portion 112, and in this case, the workability of welding can be similarly improved. By passing the pin 113 of the twelfth separator 132 through the negative electrode tab 102m of the second battery 102 and the through holes 109 and 162 of the terminal plate 161 and pushing the pin 113 into the recess 114 of the eleventh separator 131 , the negative electrode tab 102m of the second battery 102 and the terminal plate 161 are positioned. The outer peripheries of the electrode contacts 101 p and 102 m are insulated by spacers 131 and 132 except for the portion facing the opening window portion 112 and the portion constituting the voltage detection portion 160 .

In the battery unit main body 80 of this embodiment, by electrically connecting the electrode terminals 100p and 100m with different electrical polarities to each other, the stacked batteries 100 are sequentially connected, and the positive output terminal 140 and the negative output terminal 150 are respectively electrically connected to The eighth and first batteries 108 and 101 are located at opposite ends along the stacking direction, as shown in FIG. 15 . The battery cell main body 80 is manufactured by combining the respective combinations shown in FIGS. 19-21 . The combinations shown in FIGS. 19-21 are improved in weldability. As a result, the workability of welding during the manufacture of the battery cell main body 80 can be improved.

Referring to FIG. 18A , FIG. 18B and FIG. 22A , the spacers 110 are each provided with a notch 118 for exposing a part of the periphery of the clamped electrode joint 100t, and the area of the electrode joint 100t exposed through the notch 118 is used as a detection cell 100 The voltage detection part 160 of the voltage. Since the electrode tab 100t itself is used as the voltage detection portion 160, space saving can be promoted compared with the case of providing a terminal dedicated for voltage detection separate from the electrode tab 100t, with the result that the structure for voltage detection will be simplified, and Assembly of the assembled battery 50 is facilitated.

Referring to FIGS. 22 and 23 , a connector 170 provided with a connection terminal 171 (refer to FIG. 24C ) connectable to the voltage detection portion 160 is detachably attached to the voltage detection portion 160 through the insertion hole 91 a of the insulating cover 91 . The connector 170 is connected to a voltage detection device 180 through a lead wire 172 . The operation of electrically connecting the voltage detection part 160 to the voltage detection device 180 can be completed only by plugging the connector 170 . Then, the operation status of each battery 100 can be checked by monitoring the voltage detected on the voltage detection part 160 .

A plurality of voltage detection sections 160 are arranged on one same line along the stacking direction of the batteries. The connector 170 is provided with a plurality of connection terminals 171 arranged to correspond to positions of the voltage detection part 160 . The voltage detection sections 160 are arranged in half, four on the front side and four on the rear side. By establishing the correspondence between the positions of the plurality of voltage detection parts 160 and the positions of the plurality of connection terminals 171 in advance, it is possible to complete the electrical connection of the plurality of voltage detection parts 160 to the voltage detection device by simply inserting one connector 170. 180, resulting in improved operability of the electrical connection. Here, the size of the battery 100 in its thickness direction (battery height) has more or less size dispersion in the portion where the electricity generating element is allowed to exist. In the present embodiment, the electrode tab 100 t is held solely by the spacer 110 as a rigid body, and the plurality of voltage detection portions 160 are formed by the electrode tab 100 t exposed through the notch 118 . Thus, the interval between the plurality of voltage detection parts 160 is destined to be determined by the height dimension of the stacked spacers 110 . That is, the intervals of the plurality of voltage detection sections 160 can be kept constant without being affected by the dimensional dispersion of each cell height, and the positions of the plurality of voltage detection sections 160 do not cause any dispersion in the mutual relationship. The plurality of connection terminals 171 of the connector 170 does not cause any dispersion in positional relationship. Therefore, there is no need to perform complex operations, such as adjusting the height of each voltage detection part 160 , to make the relative positional relationship between the plurality of voltage detection parts 160 and the plurality of connection terminals 171 consistent. As a result, the voltage detection section 160 is simplified in structure, the plurality of voltage detection sections 160 and the plurality of connection terminals 171 can be easily collectively connected, and the inserting operability of the connector 170 is improved.

When the electrode tab 100 t has a relatively large plate thickness, the electrode tab 100 t constituting the voltage detection portion 160 is not deformed during insertion and extraction of the connector 170 . However, when the electrode tab 100t has a relatively small plate thickness, the electrode tab 100t constituting the voltage detection part 160 may be deformed during insertion and extraction of the connector 170 . Therefore, in order to prevent such deformation of the electrode tab 100t, the voltage detection part 160 is provided with a terminal plate 161 which is superimposed on the electrode tab 100t for connection. The terminal plate 161 is formed of a metal plate having a greater plate thickness than the electrode tab 100t. The spacer 110 is provided on its rear face with a notch (not shown) for receiving the terminal block 161 . By arranging the terminal block 161, it is possible to increase the strength of the voltage detection part 160 and prevent the voltage detection part 160 from being deformed due to the insertion and extraction of the connector 170, compared to the case of using only the electrode tab 100t. In addition, since the terminal plate 161 is directly connected to the electrode tab 100t, space can be saved compared to the case where the terminal plate 161 is provided separately from the electrode tab 100t.

A through hole 162 is also formed on the wiring board 161 , and the through hole 162 allows the pin 113 of the spacer 110 to be inserted. By making the pin 113 inserted into the through hole 162 bear the load applied to the terminal block 161, the load applied to the electrode tab 100t and the electricity generating element can be reduced during insertion and extraction of the connector 170.

Incidentally, when the electrode tab 100t has a relatively large plate thickness and does not suffer deformation due to insertion and extraction of the connector 170, the electrode tab 100t does not have to be provided with the terminal plate 161.

Referring to FIG. 21A , the positive electrode tab 101p sandwiched by the negative electrode tab 102m on which the terminal plate 161 is stacked is provided with a recess 100b for accommodating the terminal plate 161 . Since the positive electrode tab 101p is not allowed to overlap on the terminal plate 161, any gap does not occur between the negative electrode tab 102m and the positive electrode tab 101p. As a result, the electrode tabs 102m and 101p can be tightly held and ideally electrically connected.

The electrode tabs 100t are connected to each other by ultrasonic welding. Specifically, the electrode tabs 102m and 101p near the opening windows 112 of the spacers 131 and 132 are connected to each other by ultrasonic welding (refer to FIG. 21 ). Also, the negative electrode tab 101m near the opening window portion 112 of the spacers 121 and 122 and the bus bar 151 of the output terminal 150 are connected by ultrasonic welding (refer to FIG. 19 ). The electrode tabs 102p and 103m near the outside of the separators 121-124 are connected to each other on the outside of the separators 121-124 by ultrasonic welding. The electrode tabs 106p and 106m near the outside of the separators 127-129 are connected to each other outside the separators 127-129 by ultrasonic welding (refer to FIG. 20 and FIG. 22A).

The utility model does not rule out that the electrode joint 100t and the terminal block 161 are connected to each other by ultrasonic welding. However, when the electrode tab 100t and the terminal plate 161 are connected by ultrasonic welding and then the electrode tabs 100t are connected to each other by ultrasonic welding, the connection portion of the electrode tab 100t and the terminal plate 161 is subjected to vibration accompanying the welding, while the electrode tab 100t and the terminal plate 161 are connected to each other. The connection portion of the plates 161 is separated, which may result in a decrease in bonding strength. Thus, when connecting the electrode tabs 100t to each other by ultrasonic welding, it is preferable to connect the electrode tabs 100t and the terminal plate 161 by at least any one of pressing and using the rivets 165 . Even if the electrode tabs 100t are connected to each other by ultrasonic welding at a position in close proximity to the connection portion of the electrode tab 100t and the terminal plate 161, the connection strength between the electrode tab 100t and the terminal plate 161 can be maintained and easy maintenance of expected quality can be obtained. . During insertion and extraction of the connector 170 , the terminal plate 161 is subjected to thrust due to friction and engagement occurring between the connection terminals 171 of the connector 170 and the terminal plate 161 . The occurrence of separation at the connection portion of the electrode tab 100 t and the terminal plate 161 can be prevented by opposing the thrust force by the shear strength generated by the punching press or the rivet 165 .

FIG. 24A illustrates the main part of the battery 100 in which the terminal plate 161 is stacked and connected to the negative electrode tab 100m. Referring to FIG. 24A-FIG. 24C, in this embodiment, the negative electrode joint 100m and the terminal plate 161 are connected by pressing. The punching compaction results in the formation of a raised portion 163 on the front of the terminal plate 161 and a recessed portion behind the terminal plate 161 and the negative electrode tab 100m (refer to FIGS. 24B and 24C ). The connector 170 has a connection terminal 171 with elasticity, and is inserted into the terminal block 161 and the negative electrode tab 100m. The insertion position of the connector 170 is indicated by a two-dot chain line in FIGS. 24A and 24C . When stamping is performed, the negative electrode tab 100m and the terminal plate 161 form a convex-convex combination, and the surface along the convex-concave direction perpendicularly intersects the direction of the thrust generated during the insertion or extraction of the connector 170 . As a result, it is possible to provide resistance to thrust and prevent separation of the connection portion of the negative electrode tab 100 m and the terminal plate 161 .

Referring to FIG. 25A , the spacer 110 is provided with a recessed portion 119 allowing a protrusion 163 formed on a surface of a wiring board 161 by punching to be inserted thereinto. The concave portion 119 of the spacer 110 and the convex portion 163 on the surface of the terminal plate 161 cooperate with each other when clamping the negative electrode tab 100m. When vibration invades the terminal block 161 via the connector 170, the spacer 110 can suppress the vibration and prevent the vibration from entering the negative electrode tab 100m. As a result, the electrode tab 100t can achieve improved durability, and the assembled battery 50 can exhibit improved reliability without suffering stress concentration on the mutually bonded portions of the electrode tab. In addition, since the pushing force applied to the terminal plate 161 is captured by the spacer 110, the pushing force applied to the negative electrode tab 100m is relieved, thus, the durability of the negative electrode tab 100m can be improved. Reference numeral 113 appearing in FIG. 25A denotes a pin provided on the front face of the spacer 110 . As already described, the pin 113 of the spacer 110 on the lower position side is inserted into the through-holes 109 and 162 formed on the negative electrode tab 100m and the terminal plate 161, and fits into the recess 114 of the spacer 110 on the upper position side. .

FIG. 25B shows a state in which the negative electrode tab 100m and the terminal plate 161 are connected by the rivet 165. As shown in FIG. The head portion 165a of the rivet 165 protrudes from opposite sides of the terminal plate 161, ie, the front and the rear, and forms a convex shape. When the combination is achieved by the rivet 165, in order to prevent vibration and thrust from entering the negative electrode tab 100m, the spacer 110 is preferably provided with a recessed portion 119 into which the rivet portion 165a protruding from the front and rear of the terminal plate 161 is inserted.

Referring again to FIG. 15 and FIG. 16 , the stacked state of the battery 100 and the separator 110 in the battery cell body 80 , the shape of the electrode tab 100 t and the electrical connection state of the battery 100 will be further described below. In FIG. 16, the spacer 110 is indicated by a dotted line.

Referring first to FIG. 16, the shape of the electrode tab 100t will be described. The electrode tab 100t has various shapes. The shape of the electrode tab 100 t is determined with a view to facilitating the joining of the electrode tab 100 t in the subassemblies 81 , 82 , and 83 and facilitating the joining of the electrode tab 100 t between the subassemblies 81 , 82 , and 83 . The battery front and rear sides of the second battery 102 and the fifth battery 105 are simply arranged in reverse, while themselves remaining unchanged and using the same batteries. Likewise, the third battery 103 and the sixth battery 106 use the same battery, and the fourth battery 104 and the seventh battery 107 use the same battery. Thus, the present battery cell main body 80 includes eight batteries 101-108, however, five kinds of batteries having different shapes of the electrode tabs 100t are used. By reducing the number of battery types, the cost required to produce the battery 100 can be reduced.

The shape of the electrode tab 100 t is broadly divided into two types, a type in which the tab portion is elongated in the longer direction and is close to the outside of the separator 110 , and a type in which the entirety of the tab is hidden by the separator 110 . The former type includes the positive electrode terminal 102p of the second battery 102, the positive and negative electrode terminals 103p and 103m of the third battery 103, the negative electrode terminal 104m of the fourth battery 104, the positive electrode terminal 105p of the fifth battery 105, the sixth The positive and negative electrode terminals 106 p and 106 m of the battery 106 , and the negative electrode terminal 107 m of the seventh battery 107 . The latter type includes the remaining electrode terminals, namely, the positive and negative electrode terminals 101p and 101m of the first battery 101, the negative electrode terminal 102m of the second battery 102, the positive electrode terminal 104p of the fourth battery 104, the fifth battery 105 The negative electrode terminal 105m of the battery, the positive electrode terminal 107p of the seventh battery 107, and the positive and negative electrode terminals 108p and 108m of the eighth battery 108.

The terminal plate 161 is stacked and connected to the negative electrode tab 100m in each battery 100 . The positive electrodes 101p, 104p, and 107p stacked on the negative electrode tab 100m provided with the terminal plate 161 have recesses 100b for accommodating the terminal plate 161 (also refer to FIG. 17).

Referring now to FIG. 16, the electrical connection state of each battery 100 will be described below. In FIG. 16 , the electrically connected electrode tabs 100t are connected by connecting lines indicated by dashed-two dotted lines.

"Filled square" marked adjacent to the connection line indicates that in the first-third subassemblies 81, 82 and 83, the electrode tabs 100t near the opening window 112 of the spacer 110 are connected to each other by ultrasonic welding. “Filled circles” marked adjacent to the connection line indicate that in the first and third subassemblies 81 and 83 , the electrode tabs 100 t near the outside of the separator 110 are connected by ultraviolet welding on the outside of the separator 110 . The "blank circle" marked adjacent to the connection line indicates that the electrode contact 100t near the outside of the separator 110 is in the spacer when the subassemblies 81 and 82 and 82 and 83 are interconnected after the subassemblies 81, 82 and 83 have been assembled. The outer sides of 110 are connected to each other by ultraviolet welding.

When the first subassembly 81 is assembled, the positive electrode terminal 101p of the first battery 101 and the negative electrode terminal 102m of the second battery 102 are connected in the opening window 112, while the positive electrode terminal 102p of the second battery 102 is connected to the third battery 102 The negative electrode tab 103m of the battery 103 is connected outside the separator 110 . The negative electrode tab 101m of the first battery 101 and the bus bar 151 of the negative output terminal 150 are also connected in the opening window portion 112 (refer to FIG. 19 ).

When the second subassembly 82 is assembled, the positive electrode tab 104p of the fourth battery 104 and the negative electrode tab 105m of the fifth battery 105 are connected in the opening window portion 112 .

When the third subassembly 83 is assembled, the positive electrode terminal 107p of the seventh battery 107 and the negative electrode terminal 108m of the eighth battery 108 are connected in the opening window 112, while the positive electrode terminal 106p of the sixth battery 106 is connected to the seventh battery 108m. The negative electrode tab 107m of the battery 107 is connected outside the separator 110 . The positive electrode tab 108 p of the eighth battery 108 and the bus bar 141 of the positive output terminal 140 are connected in the opening window portion 112 .

After the subassemblies 81, 82 and 83 have been assembled, when the first subassembly 81 and the second subassembly 82 are connected, the positive electrode tab 103p of the third battery 103 and the negative electrode tab 104m of the fourth battery 104 are in the spacer 110 Connect outside. The positive electrode tab 105p of the fifth battery 105 and the negative electrode tab 106m of the sixth battery 106 are connected outside the separator 110 when the second subassembly 82 and the third subassembly 83 are connected. Thus, as a result of the electrical connection of the electrode tabs 100p and 100m having different electrical polarities, the eight stacked cells 101-108 are connected in series connection, and the positive output terminal 140 and the negative output terminal 150 are electrically connected to each other along the stacked Orient the eighth and first cells 108 and 101 at opposite ends.

On the front surface side, four voltage detection parts 160 are arranged on the same straight line along the stacking direction of the batteries, and the terminal boards 161 are located at the corresponding positions of the first, third, fifth and seventh batteries 101, 103, 105 and 107. On the negative electrode tabs 101m, 103m, 105m and 107m. On the rear surface side, four voltage detection parts 160 are arranged on the same straight line along the stacking direction of the batteries, and the terminal boards 161 are located at the corresponding positions of the second, fourth, sixth and eighth batteries 102, 104, 106 and 108. On negative electrode tabs 102m, 104m, 106m and 108m. For example, the voltage of the first battery 101 can be obtained by determining the voltage between the first voltage detecting portion 160 on the front surface side and the first voltage detecting portion 160 on the rear surface side. The voltage of the second battery 102 can be obtained by determining the voltage between the first voltage detection portion 160 on the rear surface side and the second voltage detection portion 160 on the front surface side. Similarly, the voltages of the third-eighth batteries 103-108 can be obtained.

Now, the stacked state of the battery 100 and the separator 110 in the battery cell main body 80 will be described below with reference to FIG. 15 . In FIG. 15 , elements protruding from the front of the spacer 110 represent pins 113 , while elements protruding from the rear thereof represent snap-fit claws 116 . The front surface side and the rear surface side will be described separately from each other below.

First, on the front surface side, the first and second spacers 121 and 122 sandwich the negative electrode tab 101m and the bus bar 151 of the negative output terminal 150 in a stacked state. The second and third separators 122 and 123 sandwich the positive electrode tab 102p of the second battery 102 . The third and fourth separators 123 and 124 sandwich the negative electrode tab 103m of the third battery 103 . The fifth and sixth separators 125 and 126 sandwich the positive electrode tab 104p of the fourth battery 104 and the negative electrode tab 105m of the fifth battery 105 in a stacked state. The sixth and seventh separators 126 and 127 sandwich the positive electrode tab 106p of the sixth battery 106 . The seventh and eighth separators 127 and 128 sandwich the negative electrode tab 107 m of the seventh battery 107 . The eighth and ninth separators 128 and 129 sandwich the positive electrode tab 108p of the eighth battery 108 and the bus bar 141 of the positive output terminal 140 in the stacked state.

On the rear surface side, the tenth spacer 130 is superimposed on the eleventh spacer 131 . The eleventh and twelfth separators 131 and 132 sandwich the positive electrode tab 101p of the first battery 101 and the negative electrode tab 102m of the second battery 102 in a stacked state. The twelfth and thirteenth separators 132 and 133 sandwich the positive electrode tab 103 p of the third battery 103 . The thirteenth and fourteenth separators 133 and 134 sandwich the negative electrode tab 104 m of the fourth battery 104 . The fourteenth and fifteenth separators 134 and 135 sandwich the positive electrode tab 105 p of the fifth battery 105 . The fifteenth and sixteenth separators 135 and 136 sandwich the negative electrode tab 106 m of the sixth battery 106 . The seventeenth and eighteenth separators 137 and 138 sandwich the positive electrode tab 107p of the seventh battery 107 and the negative electrode tab 108m of the eighth battery 108 in a stacked state.

Spacers 110 also have different shapes. The front and rear sides of some spacers are held inconveniently by themselves and are arranged upside down on the front surface side and the rear surface side. Furthermore, the nine spacers 121-129 on the front surface side include the same spacer, and the nine spacers 130-138 on the rear surface side include the same spacer. The battery cell body 80 includes 18 separators 121-138, and eight separators of different shapes are used. Kinds of the first spacer 121 - the eighteenth spacer 138 are shown below by using symbols #8 - #15.

Rear surface side Front surface side

The tenth spacer 130: #9 The first spacer 121: #9

The eleventh spacer 131: #12 The second spacer 122: #13

The twelfth spacer 132: #11 The third spacer 123: #10

The thirteenth partition 133: #10 The fourth partition 124: #11

The fourteenth spacer 134: #11 The fifth spacer 125: #12

The fifteenth spacer 135: #10 The sixth spacer 126: #11

The sixteenth partition 136: #11 The seventh partition 127: #10

The seventeenth spacer 137: #15 The eighth spacer 128: #9

The eighteenth isolation piece 138: #14 The ninth isolation piece 129: #8

Now, the process of assembling the assembled battery 50 in this embodiment will be described below. In Fig. 27, Fig. 29, Fig. 31, Fig. 33, Fig. 35, Fig. 37 and Fig. 39, the locations subjected to ultrasonic welding are indicated by hatching.

(Assembly of the first subassembly 81)

On the front surface side, the first and second spacers 121 and 122 sandwich the negative electrode tab 101m and the bus bar 151 of the negative output terminal 150 of the first battery 101 in a stacked state, while the negative electrode tab 101m and the negative output terminal 150 The terminal 150 is partially adjacent to the opening window 112 as shown in FIG. 26 . The pins 113 of the second separator 122 pass through the corresponding through holes 153 , 109 and 162 of the bus bar 151 , the negative electrode tab 101 m , and the terminal plate 161 , and are fitted in the recesses 114 of the first separator 121 . As shown in FIG. 27, the negative electrode tab 101m near the opening window portion 112 and the bus bar 151 are connected by ultrasonic welding. As a result, the negative output terminal 150 is electrically connected to the first battery 101 .

The tenth spacer 130 is superimposed on the eleventh spacer 131 on the rear surface side, as shown in FIG. 28 . The eleventh and twelfth spacers 131 and 132 hold the positive electrode tab 101p of the first battery 101 and the negative electrode tab 102m of the second battery 102 in a stacked state, and the electrode tabs 101p and 102m are partially close to the opening window portion 112 . The pin 113 of the twelfth separator 132 passes through the corresponding through holes 109 and 162 of the negative electrode tab 102 m and the terminal plate 161 , and is fitted in the concave portion 114 of the eleventh separator 131 . Since the terminal plate 161 cannot be superimposed on the positive electrode tab 101p, the electrode tabs 101p and 102m are tightly held to each other. The opposite surfaces of the first battery 101 and the second battery 102 were adhered with double-sided coated tape. As shown in FIG. 29, the positive electrode tab 101p and the negative electrode tab 102m near the opening window portion 112 are connected by ultrasonic welding. As a result, the first battery 101 and the second battery 102 are connected in series connection. In addition, on the front surface side, the second and third separators 122 and 123 sandwich the positive electrode tab 102p of the second battery 102, and a part of the positive electrode tab 102p is close to the outside of the separators 122 and 123 (refer to FIG. 28 and FIG. 29). The pin 113 of the third separator 123 passes through the through hole 109 of the positive electrode tab 102p, and is fitted in the recessed portion 114 of the second separator 122 .

On the front surface side, the third and fourth separators 123 and 124 sandwich the negative electrode tab 103m of the third battery 103, a part of which is close to the outside of the separators 123 and 124, as shown in FIG. The pin 113 of the fourth separator 124 passes through the corresponding through holes 109 and 162 of the negative electrode tab 103 m and the terminal plate 161 , and fits in the recess 114 of the third separator 123 . The opposite surfaces of the second battery 102 and the third battery 103 were adhered with double-sided coated tape. The positive electrode tab 102p of the second battery 102 near the outside of the separators 121-124 and the negative electrode tab 103m of the third battery 103 are connected outside the separators 121-124 by ultrasonic welding, as shown in FIG. As a result, the second battery 102 and the third battery 103 are connected in series connection. Then, on the rear surface side, the twelfth and thirteenth separators 132 and 133 sandwich the positive electrode tab 103p of the third battery 103, and a part of the positive electrode tab 103p approaches the outside of the separators 132 and 133 (refer to FIG. 30 and Figure 31). The pin 113 of the thirteenth separator 132 passes through the through hole 109 of the positive electrode tab 103p, and is fitted in the recessed portion 114 of the twelfth separator 132 .

Through these steps, the assembly of the first subassembly 81 is completed.

(Assembly of the second subassembly 82)

On the front surface side, the fifth and sixth separators 125 and 126 sandwich the positive electrode tab 104p of the fourth battery 104 and the negative electrode tab 105m of the fifth battery 105, the electrode tabs 104p and 105m overlap and partially approach the opening The window portion 112, as shown in FIG. 32 . The pin 113 of the sixth separator 126 passes through the corresponding through holes 109 and 162 of the negative electrode tab 105 m and the terminal plate 161 , and fits in the recess 114 of the fifth separator 125 . Since the positive electrode tab 104p cannot be superimposed on the terminal plate 161, the electrode tabs 104p and 105m are tightly held to each other. The opposite surfaces of the fourth cell 104 and the fifth cell 105 were adhered with double-sided coated tape. As shown in FIG. 33, the positive electrode tab 104p and the negative electrode tab 105m near the opening window portion 112 are connected by ultrasonic welding. As a result, the fourth battery 104 and the fifth battery 105 are connected in series connection. Then, on the rear surface side, the fourteenth and fifteenth separators 134 and 135 sandwich the positive electrode tab 105p of the fifth battery 105, and the positive electrode tab 105p part approaches the outside of the separators 134 and 135 (refer to FIGS. 32 and 135 ). Figure 33). The pin 113 of the fourteenth separator 134 passes through the corresponding through holes 109 and 162 of the negative electrode tab 104 m and the terminal plate 161 .

These steps complete the assembly of the second subassembly 82 .

(Assembly of the third subassembly 83)

On the front surface side, the eighth and ninth separators 128 and 129 sandwich the bus bar 141 of the positive electrode tab 108p and the positive output terminal 140 of the stacked eighth battery 108, a part of the positive electrode tab 108p and a part of the positive output terminal 140 The opening window 112 is approached, as shown in FIG. 34 . The pin 113 of the ninth separator 129 passes through the corresponding through holes 143 and 109 of the bus bar 141 and the positive electrode tab 108p, and fits in the recessed portion 114 of the eighth separator 128 . As shown in FIG. 35, the positive electrode tab 108p and the bus bar 141 close to the opening window portion 112 are welded by ultrasonic waves. As a result, the positive output terminal 140 is electrically connected to the eighth battery 108 .

On the rear surface side, the seventeenth and eighteenth spacers 137 and 138 sandwich the stacked positive electrode tab 107p of the seventh battery 107 and the negative electrode tab 108m of the eighth battery 108, the electrode tabs 107p and 108m are partially approached Open window 112, as shown in FIG. 36 . The pin 113 of the eighteenth spacer 138 passes through the corresponding through holes 109 and 162 of the negative electrode tab 108 m and the terminal plate 161 , and fits in the recess 114 of the seventeenth spacer 137 . Since the positive electrode tab 107p cannot be superimposed on the terminal plate 161, the electrode tabs 107p and 108m are tightly held. The opposing surfaces of the seventh cell 107 and the eighth cell 108 were adhered with double-sided coated tape. As shown in FIG. 37, the positive electrode tab 107p and the negative electrode tab 108m near the opening window portion 112 are connected by ultrasonic welding. As a result, the seventh battery 107 and the eighth battery 108 are connected in series connection. Then, on the front surface side, the seventh and eighth separators 127 and 128 sandwich the negative electrode tab 107m of the seventh battery 107, and the negative electrode tab 107m part is close to the outside of the separators 127 and 128 (refer to FIGS. 36 and 37 ). The pin 113 of the eighth spacer 128 passes through the negative electrode tab 107 m and through holes 109 and 162 of the terminal plate 161 , respectively, and fits in the recess 114 of the seventh spacer 127 .

On the rear surface side, the sixteenth spacer 136 is superimposed on the seventeenth spacer 137 as shown in FIG. 38 . The pin 113 of the seventeenth spacer 137 is fitted in the recess 114 of the sixteenth spacer 136 . The negative electrode tab 106 m of the sixth battery 106 is mounted on the sixteenth separator 136 , and the negative electrode tab 106 m is partially close to the outside of the separator 136 . The pin 113 of the sixteenth separator 136 passes through the corresponding through holes 109 and 162 of the negative electrode tab 106 m and the terminal plate 161 . The opposing surfaces of the sixth cell 106 and the seventh cell 107 were adhered with double-sided coated tape. On the front surface side, the positive electrode tab 106p of the sixth battery 106 is mounted on the seventh separator 127, the positive electrode tab 106p partially approaching the outside of the separator 127, as shown in FIG. The pin 113 of the seventh separator 127 passes through the through hole 109 of the positive electrode tab 106p. Then, the positive electrode tab 106p and the negative electrode tab 107m near the outer sides of the separators 127 and 128 are joined on the outer sides of the separators 127 and 128 by ultrasonic welding. As a result, the sixth battery 106 and the seventh battery 107 are connected in series connection.

These steps complete the assembly of the third subassembly 83 .

(Interconnection of subassemblies 81 and 82 and 82 and 83)

When the first subassembly 81 and the second subassembly 82 are connected, referring to FIGS. and on the rear surface side, the pin 113 of the fourteenth spacer 134 passes through the negative electrode terminal 104m of the fourth battery 104 and the corresponding through-holes 109 and 162 of the terminal plate 161, and then fits in the thirteenth spacer. into the recessed portion 114 of the spacer 133 . As a result, the first subassembly 81 and the second subassembly 82 are positioned and connected. Then, on the rear surface side, the positive electrode tab 103p of the third battery 103 and the negative electrode tab 104m of the fourth battery 104 are connected on the outside of the separators 130-135 by ultrasonic welding. As a result, the first subassembly 81 and the second subassembly 82 are connected in series connection.

When the second subassembly 82 and the third subassembly 83 are connected, on the front surface side, the pin 113 of the seventh spacer 127 is passed through the through hole 109 of the positive electrode tab 106p of the sixth battery 106, and then fitted in and on the rear surface side, the pin 113 of the sixteenth spacer 136 passes through the negative electrode tab 106m of the sixth battery 106 and the corresponding through holes 109 and 162 of the terminal block 161 , and then fit into the recessed portion 114 of the fifteenth spacer 135 . As a result, the second subassembly 82 and the third subassembly 83 are positioned and connected. Then, on the rear surface side, the positive electrode tab 105p of the fifth battery 105 and the negative electrode tab 106m of the sixth battery 106 are connected outside the separators 130-138 by ultrasonic welding. As a result, the first-third subassemblies 81, 82 and 83 are connected in series connection.

These steps complete the interconnection of the subassemblies 81 and 82 and 82 and 83 with the result that the battery cell body 80 shown in FIG. 9 is obtained.

The interconnection portion of the electrode tab 100t and the connection portion of the electrode tab 100t and the bus bars 141 and 151 are divided into a plurality of positions in the shorter direction of the battery 100 (longer direction of the separator 110). When a specific connecting portion is connected by ultrasonic welding, the electrode joints 100t to be paired can be clamped to each other by positioning the welding head of the welding device at the specific connecting portion without spreading in the stacking direction by temporarily withdrawing. The operation of other batteries is opened, and the welding operation is facilitated as a result. In addition, the degree of freedom of selection of the horn shape is increased, and automation of welding operations is facilitated. Also, the expected quality is maintained without creating the possibility of undue stress to the already connected electrode tab 100t.

(Assembly of battery unit 60, etc.)

Subsequently, insulating covers 91 and 92 are respectively installed on the front surface and the rear surface of the battery cell main body 80 (refer to FIGS. 6 and 23A ) to obtain the battery cell 60 shown in FIG. 3 .

The battery unit 60 is accommodated in the lower case 71, and the sleeve 93 is inserted into the bolt hole 111 of the spacer 110, as shown in FIG. 2 . The buffer member 94 is placed on the battery unit 60 , and the opening portion 71 a of the lower case 71 is closed with the upper case 72 . Assembly of the assembled battery 50 shown in FIG. 1 is completed by overlapping the edge portion 72a of the upper case 72 with the edge portion 71c of the peripheral wall 71b of the lower case 71 by a pressing operation. The connector 170 is inserted through the jacks 91a and 92a.

The position of the spacer 110 relative to the housing 70 is fixed by passing through bolts through the bolt holes 73 and the bushing 93 of the housing 70 . As a result, the positions of the plurality of batteries 100 relative to the case 70 are fixed.

(improved embodiment)

The embodiment in which the electrode tabs 100t are connected to each other by ultrasonic welding has been described. However, the interconnection of the electrode tabs 100t is not limited to ultrasonic welding.

(second embodiment)

The second embodiment differs from the first embodiment in that the structure of the spacer 230 and the way of interconnecting the electrode tabs 222 and 224 are changed.

Similar to the first embodiment, the assembled battery 210 of the second embodiment has a plurality of stacked batteries 220 and the electrode terminals 222 and 224 of each battery 220 are electrically connected to each other. The plate-like electrode tabs 222 and 224 are formed by drawing out from the package. The assembled battery 210 is also provided with a plate-shaped electrically insulating spacer 230 adapted to hold the electrode tabs from opposite surface sides of the electrode tabs 222 and 224 along the battery stacking direction (vertical direction in FIG. 40 ). The plurality of batteries 220 are housed in the case 240 in such a manner that the electricity generating elements are compacted.

The battery 220 is a flat-shaped battery as shown in FIG. 41 . A stacked type electricity generating element (not shown) formed by sequentially laminating a positive electrode plate, a negative electrode plate, and a separator is accommodated in the flat type main body 226 . The battery 220 is a secondary battery such as a lithium ion secondary battery. In the assembled battery 210, a plurality of batteries 220 are stacked in the same direction as the stacking direction of the electricity generating elements contained therein.

The battery 220 has a positive electrode terminal 222 and a negative electrode terminal 224 protruding from a flat body 226 comprising electricity generating elements. The negative electrode tab 224 is formed from a thin sheet of copper and the positive electrode tab 222 is formed from a thin sheet of aluminum. The plurality of batteries 220 are stacked such that the positive electrode tabs 222 and the negative electrode tabs 224 may alternate with each other along the stacking direction, that is, the electrical polarities of the electrode tabs may alternate with each other.

The cells 220 are fixed to each other by applying a double-sided coated tape or adhesive to the flat body 226 . A pair of separators 230 hold the positive electrode tab 222 and the negative electrode tab 224 together as a stacked pair. Thus, the plurality of batteries 220 are connected in series. The negative electrode tab 224 of the cell 220 forming the uppermost layer is connected to the negative output terminal 252 , while the positive electrode tab 222 of the cell 220 forming the lowermost layer is connected to the positive output terminal 250 .

The spacer 230 of the second embodiment is provided with an insulating layer 234 having an electrical insulating property and a heat dissipation layer 232 having a higher heat radiation property than the insulating layer 234 . The spacer 230 shown as an example is formed in a three-layer structure including an insulating layer 234 having insulating properties sandwiched by a heat dissipation layer 232 having heat radiation properties, as shown in FIG. 40 . When the electrode tabs 222 and 224 are sandwiched by a pair of spacers 230 each having the three-layer structure, the heat dissipation layer 232 is allowed to contact the stacked electrode tabs 222 and 224 .

The insulating layer 234 may be formed of a suitable material as long as it can impart electrical insulating properties to the spacer 230 . The heat dissipation layer 232 may be formed of a suitable material as long as it possesses higher heat radiation properties than the insulating layer 234 . By forming the heat dissipation layer 232 with a material having a higher thermal conductivity ratio than the material forming the insulation layer 234 , the heat dissipation layer 232 can have a higher heat radiation property than the insulation layer 234 . Since the insulating layer 234 enables the spacer 230 to retain its own electrical insulation properties, the material used to form the heat dissipation layer 232 is not limited to materials with electrical insulation properties, but can be selected from materials with electrical conductivity. It is sufficient to select the material used to form the heat dissipation layer 232 from the viewpoint of improving heat radiation properties. Specifically, a material having excellent heat radiation properties such as aluminum is used for the heat dissipation layer 232 . For the insulating layer 234, an insulating material such as ceramics or resin is used. When a conductive substance is selected as the material for forming the heat dissipation layer 232 , it goes without saying that the insulating layer 234 must be arranged along the plane direction of the electrode joints 222 and 224 in order to impart electrical insulating properties to the spacer 230 .

Preferably, the insulating layer 234 is formed with the smallest possible thickness within the range of ensuring electrical insulating properties. This is because heat radiation properties caused by the heat dissipation layer 232 can be improved within the limited thickness of the spacer 230 .

As shown in FIG. 42 , separator 230 is approximately as wide as battery 220 and is disposed across the entire width of electrode tabs 222 and 224 .

As shown in FIG. 40 , a pair of separators 230 holds two stacked positive electrode tabs 222 and negative electrode tabs 224 as a pair, and is disposed along the stacking direction with the positive electrode tabs 222 and the negative electrode tabs 224 together. In order to handle the two positive electrode tabs 222 and negative electrode tabs 224 as a pair, each separator 230 has a thickness approximately equal to the total thickness of the two batteries 220 and is disposed at the interval of two layers. The separators 230 are arranged alternately in one step on each electrode tab side (lateral side in the figure) of the battery 220 . Thus, the respective batteries 220 other than the batteries 220 forming the uppermost and lowermost layers at opposite ends in the stacking direction have their negative electrode tabs 224 in contact with the positive electrode tabs 222 of the other batteries 220 disposed on the upper step. , while their positive electrode tabs 222 are in contact with the negative electrode tabs 224 of the other cells disposed on the next step. As a result, a plurality of batteries 220 are connected in series connection. As mentioned above, the negative output terminal 252 is connected to the negative electrode tab 224 of the cell 220 forming the uppermost layer, and the positive output terminal 250 is connected to the positive electrode tab 222 of the cell 220 forming the lowermost layer. Incidentally, a plurality of batteries 220 may be connected in series so that the positive output terminal 250 may be connected to the battery 220 forming the uppermost layer, and the negative output terminal 252 may be connected to the battery 220 forming the lowermost layer.

The case 240 contains the battery 220 and the separator 230 . Holes are formed in the housing 240 for leading out a positive output terminal 250 and a negative output terminal 252 protruding from the stacked batteries 220 . The battery 220 and the separator 230 are securely fixed and protected within the housing 240 .

(assembly process)

Now, the assembly process of the assembled battery 210 in this embodiment will be described below.

First, as shown in FIG. 43 , the positive output terminal 250 is attached to the positive electrode tab 222 of the battery cell 220 forming the lowermost layer by ultrasonic welding. In the subsequent state , the cells 220 forming the lowermost layer are supported by the carrier 236 . Here, the support body 236 is formed of an insulating material, and is fitted to the positive electrode tab 222 and the negative electrode tab 224 with a high friction sheet, a double-sided coated tape, or an adhesive.

Subsequently, a separator 230' is installed to the positive electrode tab 222 of the cell 220 forming the lowermost layer. In order to adjust the total thickness of the entire assembled battery 210, the spacer 230' used here has a thickness of one battery. Due to this thickness, it is formed as a two-layer structure. However, the spacer 230' is provided with an insulating layer 234 and a heat dissipation layer 232, similar to the aforementioned case having a thickness equal to the total thickness of the two batteries.

Then, the next cell 220 is stacked. Adjacent cells 220 have an adhesive or double-coated tape interposed therebetween and secured to each other. The separator 230 is mounted on the positive electrode contact 222 of the stacked battery 220 . During this installation, while deforming the straightly extending positive electrode tab 222, the separator 230 presses it against the negative electrode tab 224 of the cell 220 forming the lowermost layer. The positive electrode tab 222 is formed of aluminum, which is more bendable than the negative electrode tab 224 . The negative electrode tab 224 of the battery 220 forming the lowermost layer and the positive electrode tab 222 of the battery 220 which is in contact with this tab 224 and located one layer above it produce a length difference proportional to the deformation generated in the positive electrode tab 222 when stacked. .

Subsequently, batteries 220 are stacked similarly. At this time, the separator 230 is disposed on the left side in the figure and brings the two contacts of the positive electrode tab 222 and the negative electrode tab 224 into contact in the stacking direction.

When the above stacking process is repeated and the negative output terminal 252 is connected to the negative electrode tab 224 of the battery 220 forming the uppermost layer, a stacked body as shown in FIG. 44 is formed.

Here, the stacked positive electrode tab 222 and the negative electrode tab 224 are different in length, and the end faces of the positive electrode tab 222 and the negative electrode tab 224 are not aligned. Such imperfectly aligned end faces of the positive electrode tab 222 and the negative electrode tab 224 prevent their combination. Thus, the end faces of the stacked positive electrode tab 222 and negative electrode tab 224 were aligned by using a cutter.

As shown in FIG. 45 , the aligned end faces of the electrode tabs 222 and 224 are connected with TIG welding by using a TIG welding apparatus 260 . The TIG welding device 260 is equipped with tungsten electrodes that are not affected by heat and is used to achieve welding by supplying a flow of inert gas to its surroundings. During soldering, the clamp 261, which also acts as a heat sink, holds the spacer 230 from above and below. The jig 261 maintains stability during welding and facilitates the dissipation of heat generated during welding.

With TIG welding, the electrical connection between the positive electrode tab 222 and the negative electrode tab 224 is ensured. After the entire TIG welding is finished, the assembled battery 210 as shown in FIG. 40 is completed by placing the stacked bodies in the casing 240 .

According to the second embodiment similar to the first embodiment, by sandwiching the electrode tabs 222 and 224 with the spacer 230 as described above, it is possible to provide the assembled battery 210 which possesses improved shock resistance and exhibits resistance to vibration input. influence and allow for compactness in size. This assembled battery 210 has two terminals of a positive electrode tab 222 and a negative electrode tab 224 sandwiched by a separator 230 as a pair. Since the positive electrode tab 222 and the negative electrode tab 224 are combined into a pair, they can be connected in their unchanged postures. Therefore, the operation is easy to perform and can produce a stable connection.

As a means of connecting the electrode joints, a method including sandwiching the stacked electrode joints between the machine arm and the anvil and connecting them by ultrasonic welding is available. When connecting adjacent electrode joints by ultrasonic welding, it is necessary to obtain a space above and below the electrode joints for accommodating the machine arm and the anvil. Thus, when the electrode tabs of batteries to be stacked have the same shape, the space is obtained by separating already connected regions, and the connected regions are thus subjected to force for separation. When the separated connection areas are closed to the previous state, the battery and electrode joints are subjected to unwanted forces. As a result, the connection area and the battery may be broken, and stable quality may not be obtained. On the contrary, in the second embodiment, although the electrode tabs 222 and 224 of the stacked batteries 220 have the same shape, the plurality of electrode tabs 222 and 224 sandwiched by the pair of separators 230 are located close to the separator 230. Connections are made at the outer ends. Since the ends of the positive electrode tab 222 and the negative electrode tab 224 are connected by TIG welding, the necessity of obtaining a space for receiving the machine arm is eliminated. As a result, since it is no longer necessary to separate or close the already connected regions, rupture of the connection region and the battery 220 can be avoided, and a connection of stable quality can be obtained.

The positive electrode tab 222 and the negative electrode tab 224 are connected at their ends. Thus, the lengths of the positive electrode tab 222 and the negative electrode tab 224 need only be such that these tabs can protrude slightly from the separator 230 . As a result, it is sufficient to have the positive electrode tab 222 and the negative electrode tab 224 having a smaller length than before, and the size of the assembled battery 210 is reduced.

Since the separator 230 supports the positive electrode tab 222 and the negative electrode tab 224, even when the number of batteries 220 to be stacked is large, the batteries 220 can be collectively interconnected finally after the entire stacking process is completed. Thus, the lamination process can be performed without imposing any limitation on the number of layers to be laminated.

In addition, spacers 230 each including a heat dissipation layer 232 having a heat radiation property are disposed above and below the stacked positive electrode tab 222 and negative electrode tab 224 , respectively. Thus, when the positive electrode tab 222 and the negative electrode tab 224 generate heat when they are connected by welding, the separator 230 emits heat. As a result, heat is hardly transferred to the battery 220 . , and thus, damage to the battery 220 due to heat during connection can be prevented.

Incidentally, the foregoing embodiment connects the batteries 220 by TIG welding. However, the connection of the battery 220 is not limited to TIG welding.

As shown in FIG. 46 , the stacked electrode tabs 222 and 224 may be connected to each other by laser welding by using a laser welding device 262 .

The laser welding device 262 focuses the laser light emitted from the oscillator on the ends of the stacked positive electrode tab 222 and negative electrode tab 224 by means of a lens. Accordingly, the ends of the positive electrode tab 222 and the negative electrode tab 224 are fused and connected.

In addition, as shown in FIG. 47, the stacked electrode tabs 222 and 224 may be connected to each other by friction stir welding. In this case, the friction stir tool 264 kept rotating is inserted into the end faces of the positive electrode joint 222 and the negative electrode joint 224 and caused to stir and join the materials themselves of the positive electrode joint 222 and the negative electrode joint 224 .

An increased mechanical strength of the joint is obtained because, unlike the method of melting the material, this method joins the overlapping joints without melting the material of the joint. Furthermore, this method is advantageous in that the joined materials are only deformed or bent to a very small extent.

(Improvement example)

The embodiment in which the spacer 230 is formed in the three-layer structure of the heat dissipation layer 232 - the insulation layer 234 - the heat dissipation layer 232 has been explained. However, the spacer 230 is not limited to this structure. For example, the spacer may be formed in a two-layer structure including a heat dissipation layer 232 and an insulating layer 234 . When the electrode tabs 222 and 224 are sandwiched by a pair of two-layer type spacers, the heat dissipation layer 232 on one of these spacers needs to contact either of the stacked electrode tabs 222 and 224 . Even with such a structure, when the electrode tabs 222 and 224 are connected to each other by welding, the battery 220 can be prevented from being damaged by heat.

The spacer 110 described in the first embodiment may employ a spacer provided with an insulating layer 234 and a heat dissipation layer 232 . In addition, instead of the mode of connecting the electrode tabs 100p and 100m close to the opening window portion 122 to each other by ultrasonic welding, a plurality of electrode tabs 100p and 100m sandwiched by a pair of spacers may also be used as conceived in the second embodiment. It is connected at the end near the outside of the spacer.

(third embodiment)

Similar to the first embodiment, the positioning function of the spacer during stacking of the batteries 220 can be added to the function of the spacer 230 in the second embodiment.

Next, a third embodiment will be described for a spacer having a positioning function.

As shown in FIGS. 48 and 49 , spacer 270 in the third embodiment is formed in a three-layer structure including insulating layer 274 having insulating properties sandwiched by heat dissipation layers 272 having heat radiation properties. Here, the heat dissipation layer 272 forming the uppermost layer is provided with a raised portion 271 (corresponding to a convex portion). Then, the heat dissipation layer 272 forming the lowermost layer is provided with a concave portion 273 . The convex portion 271 and the concave portion 273 have approximately the same diameter and depth, and are provided at corresponding positions on the front and rear surfaces of the heat dissipation layer 272 .

Thus, when the separators 270 are stacked so as to sandwich the electrode tabs 222 and 224 of the battery 220 , the separators 270 are mated with each other in a combination of convex and concave, as shown in FIG. 50 . Here, the electrode tabs 222 and 224 of the battery 220 are respectively preformed thereon with hole portions 223 and 225 allowing the protrusion portion 271 of the separator 270 to be inserted therethrough. Similar to the first embodiment, the electrode tabs 222 and 224 have hole portions 223 and 225 formed thereon, and the convex portion 271 and the concave portion 273 form the joint 117 .

The stacked body shown in FIG. 50 is obtained by a process of passing the electrode tabs 222 and 224 of the batteries 220 as a pair through the protrusion 271 of the separator 270 while fitting the separators 270 to each other. Similar to the second embodiment, the end faces of the electrode tabs 222 and 224 of the formed laminate are aligned with a cutter. Connect the aligned end faces by welding. As a result, the assembled battery in which the stacked body is disposed in the case 240 is completed.

Incidentally, the spacer 270a provided in the lowermost stage has formed thereon only a protrusion and no recess formed thereon, which protrusion fits into the recess 273 of the spacer 270 provided in the uppermost step. Thus, the spacer 270b provided at the uppermost stage has formed thereon only a concave portion without a raised portion, which is fitted with the raised portion 271 of the spacer 270 of the next step. Thus, unnecessary protrusions 271 and recesses 273 are allowed to remain in the uppermost and lowermost layers.

The spacer 270 of the third embodiment is provided with the convex portion 271 and the concave portion 273 as described above. The convex portion 271 of the spacer 270 passes through the electrode tabs 222 and 224 of the battery 220 and is then fitted into the concave portion 273 . As a result, the spacers 270 are positioned relative to each other, and the electrode tabs 222 and 224 are also positioned. That is, battery 220 is also positioned. The mutual engagement of the raised portion 271 and the recessed portion 273 of the spacer 270 as achieved above facilitates positioning during the stacking process.

Obviously, the utility model is not limited to the specific embodiment shown and described above, but various changes and improvements can be made without departing from the technical concept of the utility model.

The entire disclosures of Japanese Patent Application Nos. 2004-310545 and 2004-376184, filed October 26, 2004 and December 27, 2004, including specification, claims, drawings and abstract, are hereby incorporated in their entirety Reference.

Claims (20)

1. A combined battery, comprising: A plurality of flat batteries, each of which is provided with a package for encapsulating an electric generating element and an electrode joint drawn from the package to the outside, the plurality of flat batteries are stacked, and it is characterized in that, along the stacking direction, each other Electrode tabs of adjacent flat cells are electrically connected to each other, and the assembled battery further includes: An insulating plate sandwiching the electrode tab from opposite surface sides of the electrode tab along a stacking direction of the plurality of flat batteries and having an electrical insulating property. 2. The assembled battery according to claim 1, wherein one of the pair of insulating plates sandwiching the electrode tab is also used to sandwich the other electrode tab. 3. The assembled battery according to claim 1, wherein the insulating plates are connected to each other. 4. The assembled battery according to claim 1, wherein the pair of insulating plates sandwiching the electrode joints is provided with an engaging member adapted to pass through the electrode joints in the stacking direction. to fix the electrode connector. 5. The assembled battery according to claim 4, characterized in that The electrode joints are provided with through holes along the stacking direction, and The engaging member is provided with a protrusion adapted to be inserted into a through hole provided on one of the insulating plates arranged in pairs, and a recess adapted to allow insertion therein. The front end of the protrusion inserted into the through hole on the other of the paired insulating plates. 6. The assembled battery according to claim 5, characterized in that The insulating plates are respectively provided with a protrusion provided on one of the opposing surfaces in the stacking direction and a recess provided on the other of the opposing surfaces in the stacking direction. on, and The protruding portion and the concave portion are arranged on the same straight line along the stacking direction. 7. The assembled battery according to claim 1, characterized in that The insulating plates are respectively provided with notches for exposing part of the periphery of the clamped electrode joints, and The area of the electrode tab exposed through the notch serves as a voltage detection portion that detects the voltage of each of the flat batteries. 8. The assembled battery according to claim 7, further comprising a connector provided with a connection terminal connectable to the voltage detection part and detachably attached to the voltage detection part. 9. The assembled battery according to claim 8, characterized in that the plurality of voltage detection parts are arranged on the same straight line along the stacking direction, and The connector is provided with a plurality of connection terminals corresponding to the positions of the voltage detection parts. 10 . The assembled battery according to claim 7 , wherein the voltage detection part is provided with a voltage detection wiring board stacked and connected to the electrode terminals. 11 . 11 . The assembled battery according to claim 10 , wherein the electrode joints stacked and clamped on the electrode joint provided with the voltage detection wiring board are provided with a recess for receiving the voltage detection wiring board. 12 . 12. The assembled battery according to claim 10, characterized in that said electrode joints are connected to each other by ultrasonic welding, and The electrode joint and the voltage detection wiring board are connected by stamping or using rivets. 13. The assembled battery according to claim 10, characterized in that The electrode joint and the voltage detection wiring board are connected by stamping or using a rivet with a head, and Each insulating plate is provided with a concave portion that allows a protrusion formed on the surface of the voltage detection terminal board by punching or the head of a rivet to be inserted thereinto. 14. The assembled battery according to claim 1, characterized in that The insulating plate is provided with an opening window portion penetratingly formed along the stacking direction, The plurality of electrode joints are stacked, close to the opening window, and sandwiched by the pair of insulating plates, and The plurality of flat cells are electrically connected by interconnecting electrode tabs near the opening window. 15. The assembled battery according to claim 1, characterized in that The electrode joints are sandwiched by insulating plates, and a part of the electrode joints is close to the outer side of the insulating plates arranged in pairs, and The plurality of flat cells are electrically connected by interconnecting electrode tabs near the outside of the insulating plate. 16. The assembled battery of claim 1, further comprising positive and negative assembled battery output terminals, and wherein The insulating plate is provided with an opening window portion penetratingly formed along the stacking direction, The electrode joint and one of the output terminals of the assembled battery are stacked, close to the opening window, and sandwiched by the pair of insulating plates, and Each of the assembled battery output terminals is electrically connected to the flat battery by connecting an electrode contact near the opening window and the assembled battery output terminal. 17. The assembled battery according to claim 16, characterized in that a plurality of stacked flat cells connected in series by electrically connecting electrode tabs of different polarities, and The positive assembled battery output terminal and the negative assembled battery output terminal are electrically connected to the batteries located at two opposite ends along the stacking direction. 18. The assembled battery according to claim 1, wherein the insulating plate is provided with an insulating layer having an electrical insulating property and a heat dissipation layer having a higher heat radiation property than the insulating layer. 19. The assembled battery according to claim 1, characterized in that The plurality of electrode joints are stacked, their ends are close to the outer side of the insulating plate, and are clamped by the pair of insulating plates, and The plurality of flat cells are electrically connected by interconnecting the ends of the electrode tabs near the outside of the insulating plate. 20. The assembled battery of claim 1, further comprising a case for fixing a position of the spacer and accommodating a plurality of flat batteries.

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