JP2012221804A - Battery pack - Google Patents

Abstract

An assembled battery having excellent workability and capable of preventing breakage of an electrode tab is provided.
An assembled battery includes a plurality of laminated batteries and a plurality of insulating plates. The plurality of laminated batteries 1 to n are stacked via the plurality of insulating plates 11 to 1n-1 so that the positive electrode tabs 41 and the negative electrode tabs 42 are alternately arranged in the stacking direction DR1. Each of the positive electrode tab 41 and the negative electrode tab 42 is bent in the stacking direction DR1, and the bent portion faces the outside in the planar direction of the laminated battery. Between the two adjacent laminated batteries, the bent portion of the positive electrode tab 41 is welded to the bent portion of the negative electrode tab 42, and the plurality of laminated batteries 1 to n are connected in series.
[Selection] Figure 1

Description

  The present invention relates to an assembled battery.

  In a flat unit cell, in particular, a laminate type battery generally has a shape in which a thin plate-like positive electrode terminal and a negative electrode terminal extend in one direction, and a battery using a laminate by laminating laminate type batteries. The pack can have a higher capacity and / or a higher voltage.

  After laminating these flat unit cells, when connecting the terminals in series by means such as welding, if a plurality of terminals are connected in the terminal laminating direction, the two terminals to be connected Other terminals are obstructing the connection of the two terminals to be connected, and the connection work becomes difficult.

  For this problem, it is assumed that the terminals other than the terminal to be connected do not get in the way, but the terminals other than the terminal to be connected may be bent. Get higher.

  On the other hand, as a method of solving the above problem, there is a method of connecting terminals while laminating flat unit cells. However, even in this method, if the terminals are to be connected so as not to be short-circuited, the terminal of the unit cell at the end of the stacked flat unit cell interferes with the connection.

  Considering workability, it is preferable to proceed with the connection work at a stretch. Therefore, it is better to connect the terminals after laminating flat unit cells. Therefore, there is a demand for an assembled battery that is more workable and has a low possibility of short circuit.

  Therefore, conventionally, a method of easily connecting electrode tabs between single cells is known (Patent Document 1). In Patent Document 1, each laminated battery includes a positive electrode tab and a negative electrode tab each including an extended part extending in one direction from the power generation element and an extended part protruding inward in the plane direction of the laminated battery from the extended part. Have. In a certain laminated battery, the protruding portion of the positive electrode tab is bent in the thickness direction of the laminated battery at the boundary with the extended portion, and the bent portion is connected to the bent portion of the negative electrode tab of the adjacent laminated battery. . Also, in a certain laminated battery, the protruding portion of the negative electrode tab is bent in the opposite direction to the protruding portion of the positive electrode tab at the boundary with the extended portion, and the bent portion is the reverse bent portion of the positive electrode tab of the adjacent laminated battery Connected to.

  Thus, in Patent Document 1, each laminated battery has an L-shaped positive electrode tab and a negative electrode tab arranged so that the protruding portions face each other, and the bent part of the positive electrode tab is in the plane direction of the laminated battery. Connected to the bent portion of the negative electrode tab of the adjacent laminated battery on one side inside, and the bent portion of the negative electrode tab is connected to the bent portion of the positive electrode tab of the adjacent laminated battery on the other side inside in the plane direction of the laminated battery By being connected, a plurality of laminated batteries are connected in series.

JP 2005-190885 A

  However, since the laminated battery disclosed in Patent Document 1 has an L-shaped positive electrode tab and a negative electrode tab, the protruding portions of the positive electrode tab and the negative electrode tab are caught when the laminated battery is conveyed, and the positive electrode tab and the negative electrode tab are caught. May damage. In addition, the bent part of the positive electrode tab is connected to the bent part of the negative electrode tab inside the plane of the laminated battery, so the positive electrode tab and the negative electrode tab other than the positive electrode tab and the negative electrode tab to be connected are obstructive. May be worse.

  Accordingly, the present invention has been made to solve such a problem, and an object of the present invention is to provide an assembled battery that is excellent in workability and can prevent breakage of an electrode tab.

  According to the embodiment of the present invention, the assembled battery includes a plurality of laminated batteries. Each of the plurality of laminated batteries has rectangular first and second electrode tabs having different polarities, and the plurality of laminated batteries are alternately arranged with the first electrode tabs and the second electrode tabs. As described above, they are stacked via an insulating plate and connected in series. And the 1st score line toward the inner side from the outside of the width direction of the 1st electrode tab in the desired position from the tip part of the 1st electrode tab of the 1st laminate type battery among a plurality of laminate type batteries And a first bent portion having a structure in which a part on the tip end side of the first electrode tab with respect to the first score line is bent in the thickness direction of the laminated battery is adjacent to the first laminated battery. A second cut line is provided from the front end of the second electrode tab of the second laminated battery to a desired position from the outer side to the inner side in the width direction of the second electrode tab. Also, the second electrode tab is welded to a second bent portion having a structure in which a part of the tip end side of the second electrode tab is bent in the thickness direction of the laminated battery.

  According to the embodiment of the present invention, the assembled battery includes a plurality of laminated batteries, a plurality of first connection terminals, and a plurality of second connection terminals. Each of the plurality of laminated batteries has rectangular first and second electrode tabs having different polarities, and the plurality of laminated batteries are alternately arranged with the first electrode tabs and the second electrode tabs. As described above, they are stacked via an insulating plate and connected in series. The plurality of first connection terminals are provided corresponding to the plurality of first electrode tabs, and each of the plurality of first connection terminals faces the outside in the width direction of the first electrode tab and is laminated. It has the 1st bending part bent in the thickness direction of the battery, and is welded to the corresponding 1st electrode tab. The plurality of second connection terminals are provided corresponding to the plurality of second electrode tabs, and each of the plurality of second connection terminals faces the outside in the width direction of the second electrode tab and is laminated. It has the 2nd bending part bent in the thickness direction of the battery, and is welded to the corresponding 2nd electrode tab. And the 1st bending part of the 1st connecting terminal welded to the 1st electrode tab of the 1st lamination type battery among a plurality of lamination type batteries is the 2nd adjacent to the 1st lamination type battery. Are welded to the second bent portion of the second connection terminal welded to the second electrode tab of the laminated battery.

  In the assembled battery according to the embodiment of the present invention, adjacent first and second laminated batteries among the plurality of laminated batteries connected in series have the first bent portion of the first electrode tab. The second electrode tab is connected by welding to the second bent portion. Each of the first and second bent portions is bent in the thickness direction of the laminated battery, and is disposed so as to face the outside in the planar direction of the laminated battery. As a result, the first bent portion is welded to the second bent portion from the outside in the planar direction of the laminated battery, and the electrode tabs other than the first and second electrode tabs to be connected do not get in the way. Further, since the first and second electrode tabs are formed in a rectangular shape, the first and second electrode tabs are not caught when a plurality of laminated batteries are transported.

  Therefore, it is excellent in workability and can prevent the electrode tab from being damaged.

  In the assembled battery according to the embodiment of the present invention, the adjacent first and second laminated batteries among the plurality of laminated batteries connected in series are welded to the first electrode tab. The first bent portion of one connection terminal is connected by being welded to the second bent portion of the second connection terminal welded to the second electrode tab. Each of the first and second bent portions is bent in the thickness direction of the laminated battery, and is disposed so as to face the outside in the planar direction of the laminated battery. As a result, the first bent portion is welded to the second bent portion from the outside in the planar direction of the laminated battery, and the electrode tabs other than the first and second electrode tabs to be connected do not get in the way. Further, since the first and second electrode tabs are formed in a rectangular shape, the first and second electrode tabs are not caught when a plurality of laminated batteries are transported.

  Therefore, it is excellent in workability and can prevent the electrode tab from being damaged. In addition, the degree of freedom of the material surface of the connection terminal is increased, and welding between the electrode tabs is possible with an optimal material configuration for the welding means, improving the reliability of the connection portion between the first and second laminated batteries. it can.

FIG. 1 is a schematic view of an assembled battery according to an embodiment of the present invention. FIG. 2 is a plan view of the laminated battery shown in FIG. FIG. 3 is a cross-sectional view of the laminated battery taken along line III-III shown in FIG. FIG. 4 is an enlarged plan view of a part of the laminated battery shown in FIG. FIG. 5 is a perspective view of a part of the laminated battery shown in FIG. FIG. 6 is a perspective view of a part of the laminated battery and the insulating plate shown in FIG. FIG. 7 is a side view of the assembled battery as viewed from the direction C shown in FIG. FIG. 8 is a process diagram showing a method of manufacturing the assembled battery shown in FIG. FIG. 9 is a plan view for explaining another production method for producing the bent portions of the positive electrode tab and the negative electrode tab. FIG. 10 is a schematic view of another assembled battery according to the embodiment of the present invention. FIG. 11 is a perspective view of a part of the laminated battery shown in FIG. 12 is a perspective view of a part of the laminated battery and the insulating plate shown in FIG. FIG. 13 is a side view of the assembled battery as seen from the direction C shown in FIG. FIG. 14 is a process diagram showing a method of manufacturing the assembled battery shown in FIG.

  Embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

  FIG. 1 is a schematic view of an assembled battery according to an embodiment of the present invention. Referring to FIG. 1, an assembled battery 100 according to an embodiment of the present invention includes laminated batteries 1 to n (n is an integer of 2 or more) and insulating plates 11 to 1n-1.

  Each of the laminated batteries 1 to n has a positive electrode tab 41 and a negative electrode tab 42. Laminated batteries 1 to n are stacked via insulating plates 11 to 1n-1 such that positive electrode tabs 41 and negative electrode tabs 42 are alternately arranged in the stacking direction DR1.

  Each of the insulating plates 11 to 1n-1 is made of, for example, polyethylene terephthalate or polycarbonate. The insulating plate 11 is disposed between the laminated batteries 1 and 2. The insulating plate 12 is disposed between the laminated batteries 2 and 3. Similarly, the insulating plate 1n-1 is disposed between the laminated batteries n-1 and n.

  The negative electrode tab 42 of the laminated battery 1 is welded to the positive electrode tab 41 of the laminated battery 2, and the negative electrode tab 42 of the laminated battery 2 is welded to the positive electrode tab 41 of the laminated battery 3. Further, the negative electrode tab 42 of the laminate type battery 3 is welded to the positive electrode tab 41 of the laminate type battery 4, and the negative electrode tab 42 of the laminate type battery 4 is welded to the positive electrode tab 41 of the laminate type battery 5. Hereinafter, similarly, the negative electrode tab 42 of the laminated battery n-2 is welded to the positive electrode tab 41 of the laminated battery n-1, and the negative electrode tab 42 of the laminated battery n-1 is the positive electrode of the laminated battery n-1. It is welded to the tab 41.

  The positive electrode tab 41 of the laminated battery 1 and the negative electrode tab 42 of the laminated battery n are connected to the protection circuit of the battery pack that houses the assembled battery 100, respectively.

  Thus, the assembled battery 100 has a structure in which n laminated batteries 1 to n are connected in series.

  FIG. 2 is a plan view of the laminated battery 2 shown in FIG. 3 is a cross-sectional view of the laminated battery 2 taken along the line III-III shown in FIG. Referring to FIGS. 2 and 3, laminated battery 2 has a rectangular planar shape, and includes a positive electrode tab 41, a negative electrode tab 42, a power generation element 43, and a laminate film 44.

  The power generation element 43 includes a positive electrode, a negative electrode, and a separator. The power generation element 43 has a structure in which a positive electrode and a negative electrode are stacked via a separator. Further, the power generation element 43 is laminated by a laminate film 44.

  One end of the positive electrode tab 41 is connected to the positive electrode of the power generation element 43, and the other end side is drawn out through the laminate film 44. A part 411 of the positive electrode tab 41 that is pulled out to the outside is bent in the thickness direction of the laminated battery 2 (direction perpendicular to the paper surface of FIG. 2).

  One end of the negative electrode tab 42 is connected to the negative electrode of the power generation element 43, and the other end side is drawn out through the laminate film 44. The negative electrode tab 42 has a portion 421 of a portion pulled out to the outside and is bent in the thickness direction of the laminated battery 2 (direction perpendicular to the paper surface of FIG. 2).

  The laminate film 44 has a rectangular planar shape, and has a thickness of 70 to 330 μm, for example. Then, the laminate film 44 laminates a part of the positive electrode tab 41, a part of the negative electrode tab 42, and the power generation element 43. In addition, the laminate film 44 includes a seal portion 441 and a protruding portion 442. The protruding portion 442 is disposed inside the seal portion 441 in the in-plane direction DR2 of the laminated battery 2. The protruding portion 442 protrudes from the seal portion 441 corresponding to the power generation element 43.

  The seal portion 441 includes seal portions 4411 to 4414. The seal portions 4411 and 4412 are formed on the long side of the rectangle of the laminate film 44, and the seal portions 4413 and 4414 are formed on the short side of the laminate film 44.

  Then, the positive electrode tab 41 and the negative electrode 42 are drawn to the outside through the seal portion 4413.

  In FIG. 2, the positive electrode tab 41 and the negative electrode tab 42 are drawn from the same side of the laminate film 44. However, in the embodiment of the present invention, the present invention is not limited to this, and the positive electrode tab 41 and the negative electrode tab 42. May be drawn from different sides of the laminate film 44.

  The positive electrode of the power generation element 43 has, for example, a structure in which a layer (positive electrode mixture layer) made of a positive electrode mixture containing a positive electrode active material, a conductive additive, a binder and the like is formed on one side or both sides of the current collector.

For example, when the laminated battery 2 is a lithium ion secondary battery, the positive electrode active material is made of an active material that can occlude and release lithium ions. Such a positive electrode active material is, for example, a lithium-containing transition metal having a layered structure represented by Li _{1 + x} MO ₂ (−0.1 <x <0.1, M: Co, Ni, Mn, Al, Mg, etc.) Oxides, LiMn ₂ O ₄ , lithium manganese oxide having a spinel structure in which some of the elements are replaced with other elements, and olivine type compounds represented by LiMPO ₄ (M: Co, Ni, Mn, Fe, etc.) Consisting of either.

The lithium-containing transition metal oxide having a layered structure is, for example, LiCoO ₂ , LiNi _1-x Co _xy Al _y O ₂ (0.1 ≦ x ≦ 0.3, 0.01 ≦ y ≦ 0.2 And an oxide containing at least Co, Ni and Mn (LiMn _1/3 Ni _1/3 Co _1/3 O ₂ , LiMn _5/12 Ni _5/12 Co _1/6 O ₂ , LiNi _3/5 Mn _{1 / 5} Co _1/5 O ₂ ).

  The current collector of the positive electrode is made of, for example, an aluminum foil or an aluminum alloy foil. The thickness of the current collector varies depending on the size and capacity of the battery, but is, for example, 0.01 to 0.02 mm.

  The positive electrode is produced by the following method. A positive electrode mixture containing a positive electrode active material, a conductive additive such as graphite, acetylene black, carbon black, and fibrous carbon, and a binder such as polyvinylidene fluoride (PVDF) is mixed with N-methyl-2-pyrrolidone (NMP). ) Or the like to prepare a paste-like or slurry-like composition uniformly dispersed (the binder may be dissolved in the solvent). And this composition is apply | coated on the electrical power collector of a positive electrode, it dries, and the thickness of a positive mix layer is adjusted by press processing as needed. Thereby, a positive electrode is produced.

  In the embodiment of the present invention, the positive electrode may be manufactured using a method other than the method described above.

  The thickness of the positive electrode mixture layer in the positive electrode is preferably 30 to 100 μm per side. Moreover, it is preferable that content of each structural component in a positive mix layer shall be positive electrode active material: 90-98 mass%, conductive support agent: 1-5 mass%, and binder: 1-5 mass%.

  The positive electrode tab 41 is made of a metal foil or ribbon such as a partial clad of aluminum or aluminum containing aluminum or an aluminum alloy or an alloy.

  And the thickness of the positive electrode tab 41 is 50-300 micrometers. That is, by setting the thickness of the positive electrode tab 41 to 50 μm or more, it is possible to prevent the positive electrode tab 41 from being cut during welding of the positive electrode tab 41 and to prevent the positive electrode tab 41 from being broken by pulling and bending. it can. Further, by setting the thickness of the positive electrode tab 41 to 300 μm or less, it is possible to prevent a gap in the thickness direction from being generated in the seal portion 4413 of the laminate film 44.

  In addition, in order to increase the adhesive strength between the positive electrode tab 41 and the laminate film 44, a resin adhesive layer (for example, the laminate film 44) is previously provided at a position where the positive electrode tab 41 is expected to be positioned on the seal portion 4413. You may provide the contact bonding layer comprised by resin of the same kind as resin which comprises the heat sealing resin layer which the metal laminate film to comprise has.

  As a method of connecting the current collector in the positive electrode and the positive electrode tab 41, various methods such as resistance welding, ultrasonic welding, laser welding, caulking, and a method using a conductive adhesive can be employed.

  For example, when the laminated battery 2 is a lithium ion secondary battery, the negative electrode includes an active material that can occlude and release lithium ions. Such negative electrode active materials occlude and release lithium ions such as graphite, pyrolytic carbons, cokes, glassy carbons, fired organic polymer compounds, mesocarbon microbeads (MCMB), and carbon fibers. It consists of one or a mixture of two or more possible carbon-based materials.

In addition, the negative electrode active material may be an element such as Si, Sn, Ge, Bi, Sb, or In, an alloy of Si, Sn, Ge, Bi, Sb, or In, a lithium metal such as a lithium-containing nitride, or a lithium oxide. It consists of a compound (LiTi ₃ O ₁₂ or the like) that can be charged and discharged at a low voltage, lithium metal, and a lithium / aluminum alloy.

  These negative electrode active materials include a conductive additive (made of the same material as the positive electrode conductive additive), a binder (a binder of PVDF, rubber binder such as styrene butadiene rubber (SBR) and carboxymethyl cellulose (CMC), etc. ) Is added as appropriate to the negative electrode mixture, and the current collector is a finished product (negative electrode mixture layer) using the current collector as a core material, or the above-described various alloys or lithium metal foils. Those laminated on the surface are used as the negative electrode.

  And a negative electrode is produced by the following method. A paste in which a negative electrode mixture containing the above-described negative electrode active material, a binder, and, if necessary, a conductive additive such as graphite, acetylene black, and carbon black is uniformly dispersed using a solvent such as NMP. Alternatively, a slurry-like composition is prepared (the binder may be dissolved in a solvent). And this composition is apply | coated on a negative electrode electrical power collector, it dries, and the thickness or density of a negative mix layer is adjusted by press processing as needed. Thereby, a negative electrode is produced.

  In the embodiment of the present invention, the negative electrode may be manufactured using a method other than the method described above.

  As the current collector for the negative electrode, a copper foil is suitable. And although the thickness of an electrical power collector is based on the magnitude | size or capacity | capacitance of a battery, it is preferable that it is 0.05-0.02 mm, for example.

  The thickness of the negative electrode mixture layer in the negative electrode is preferably 30 to 100 μm per side. Moreover, it is preferable that content of each structural component in a negative mix layer is 90-98 mass% of negative electrode active materials, and 1-5 mass% of binders. Moreover, when using a conductive support agent for a negative electrode, it is preferable that content of the conductive support agent in a negative mix layer is 1-5 mass%.

  The negative electrode tab 42 is made of a metal foil or ribbon such as nickel, nickel-plated copper, and nickel-copper clad. Moreover, it is preferable that the thickness of the negative electrode tab 42 is 50-300 micrometers similarly to the positive electrode ab 41. FIG.

  That is, by setting the thickness of the negative electrode tab 42 to 50 μm or more, it is possible to prevent the negative electrode tab 42 from being cut during welding of the negative electrode tab 42 and to prevent the negative electrode tab 42 from being torn by pulling and bending. it can. Further, by setting the thickness of the negative electrode tab 42 to 300 μm or less, it is possible to prevent a gap in the thickness direction from being generated in the seal portion 4413 of the laminate film 44.

  In order to increase the adhesive strength between the negative electrode tab 42 and the laminate film 44, a resin adhesive layer (for example, the laminate film 44 is previously provided on the negative electrode tab 42 where it is planned to be positioned at the seal portion 4413. You may provide the contact bonding layer comprised by resin of the same kind as resin which comprises the heat sealing resin layer which the metal laminate film to comprise has.

  Various methods such as resistance welding, ultrasonic welding, laser welding, caulking, and a method using a conductive adhesive can be employed for connection between the current collector in the negative electrode and the negative electrode tab 42.

  The separator is made of, for example, a porous film or a nonwoven fabric made of polyethylene, polyolefin (such as a copolymer of polypropylene and propylene), a fusion of polyethylene and polypropylene, polyethylene terephthalate, and polybutylene terephthalate.

  The thickness of the separator is preferably 10 to 50 μm, and the porosity is preferably 30 to 70%.

  Moreover, the effect which prevents a short circuit can be improved and the reliability of a battery can be improved more by using several separators, such as overlapping a porous film and a nonwoven fabric.

When the laminate battery 2 is a lithium ion secondary battery, the electrolyte used for the laminate battery 2 is, for example, a solution (non-aqueous solution) in which a solute such as LiPF ₆ or LiBF ₄ is dissolved in a high dielectric constant solvent or an organic solvent. Electrolyte). The high dielectric constant solvent is composed of any of ethylene carbonate (EC), propylene carbonate (PC), and γ-butyrolactone (BL). The organic solvent is composed of a low-viscosity solvent such as linear dimethyl carbonate (DMC), diethyl carbonate (DEC), and methyl ethyl carbonate (EMC).

  In addition, it is preferable to use the mixed solvent of the high dielectric constant solvent mentioned above and a low-viscosity solvent as electrolyte solution solvent. Alternatively, PVDF, a rubber-based material, an alicyclic epoxy, a material having an oxetane-based three-dimensional crosslinked structure, and the like may be mixed and solidified into the above-described solution to form a polymer electrolyte.

  Each of the laminated batteries 3 to n-1 shown in FIG. 1 has the same configuration as the laminated battery 2 described above, and the laminated battery 1 shown in FIG. 1 includes the positive electrode tab 41 of the laminated battery 2 described above. 1 has the same configuration as that of the laminated battery 2 except that a portion 411 of the laminated battery 2 is not bent in the thickness direction of the laminated battery 2, and the laminated battery n shown in FIG. The configuration is the same as that of the laminated battery 2 except that a portion 421 is not bent in the thickness direction of the laminated battery 2.

  FIG. 4 is an enlarged plan view of a part of the laminated battery 2 shown in FIG. Referring to FIG. 4, laminated battery 2 has a rectangular positive electrode tab 41 and a negative electrode tab 42. The rectangular positive electrode tab 41 is cut along a cut line 412 from the outside toward the inside in the planar direction DR2 of the laminated battery 2. As a result, a portion 411 is formed.

  The cut line 412 has a start end 412A that is a start end of the cut and a terminal end 412B that is the end of the cut. The distance L1 between the start end portion 412A and the tip end portion of the positive electrode tab 41 is set to a value larger than the distance L2.

  In addition, the rectangular negative electrode tab 42 is cut along the cut line 422 from the outside to the inside in the planar direction DR2 of the laminated battery 2. As a result, a portion 421 is formed.

  The cut line 422 includes a start end 422A that is a start end of the cut and a terminal end 422B that is the end of the cut. The distance between the start end 422A and the tip of the negative electrode tab 42 is set to a distance L1, and the distance between the end 422B and the tip of the negative electrode tab 42 is set to a distance L2.

  The distance L3 is determined by the maximum current value flowing through the laminated battery 2.

  Similarly to the positive electrode tab 41 and the negative electrode tab 42 of the laminate type battery 2 shown in FIG. 4, the positive electrode tab 41 and the negative electrode tab 42 of the laminate type batteries 3 to n−1 have parts 411 and 421, respectively. Further, the positive electrode tab 41 of the laminated battery 1 remains flat in the planar direction DR2 of the laminated battery 1, and the negative electrode tab 42 of the laminated battery 1 is the same as the negative electrode 42 of the laminated battery 2 shown in FIG. As shown in FIG. Further, the positive electrode tab 41 of the laminated battery n has a portion 411 like the positive electrode tab 41 of the laminated battery 2 shown in FIG. 4, and the negative electrode tab 42 of the laminated battery n is a plane of the laminated battery n. It remains flat in the direction DR2.

  In this way, the positive electrode tab 41 and the negative electrode tab 42 of the laminated batteries 2 to n−1 are cut portions 411 and 421 that are cut from the outside toward the inside in the planar direction DR2 of the laminated batteries 2 to n−1, respectively. The negative electrode tab 42 of the laminated battery 1 has a cut portion 421 that is cut from the outside to the inside in the planar direction DR2 of the laminated battery 1, and the positive electrode tab 41 of the laminated battery n is a laminated type. The battery n has a cut portion 411 that is cut from the outside toward the inside in the planar direction DR2.

  The distance L1 between the start end portion 412A and the tip end portion of the positive electrode tab 41 is set to be longer than the distance L2 between the end portion 412B and the tip end portion of the positive electrode tab 41, and the distance between the start end portion 422A and the tip end portion of the negative electrode tab 42 is set. L1 is also set longer than the distance L2 between the end portion 422B and the tip of the negative electrode tab 42. This makes it easy to bend the part 411 of the positive electrode tab 41 along the line segment Ln1 from the terminal end 412B to the tip of the positive electrode tab 41, and along the line segment Ln2 from the terminal end 422B to the tip of the negative electrode tab 42. This is because the portion 421 of the negative electrode tab 42 is easily bent.

  That is, when L1> L2, the force for bending the portions 411 and 421 is concentrated on the portion along the line segment Ln1 of the positive electrode tab 41 or the portion along the line segment Ln2 of the negative electrode tab 42, respectively. This is because the portions 411 and 421 are bent starting from the portions along the lines Ln1 and Ln2, so that the portion 411 is always bent along the line segment Ln1, and the portion 421 is always bent along the line segment Ln2.

  FIG. 5 is a perspective view of a part of the laminated batteries 1 to 3 shown in FIG. With reference to (a) of FIG. 5, the positive electrode tab 41 of the laminate type battery 1 does not have a bent part, and the negative electrode tab 42 of the laminate type battery 1 has a bent part 42A. The bent portion 42 </ b> A is formed by bending a part 421 of the negative electrode tab 42 toward the protruding portion 442 of the laminated battery 1. The bent portion 42A is arranged facing the outside of the negative electrode tab 42 in the planar direction DR2 of the laminated battery 1.

  Referring to FIG. 5B, the positive electrode tab 41 of the laminated battery 2 has a bent portion 41A, and the negative electrode tab 42 of the laminated battery 2 has a bent portion 42A. The bent portion 41A is formed by bending a portion 411 of the positive electrode tab 41 toward the protruding portion 442 of the laminated battery 2, and the bent portion 42A is opposite to the protruding portion 442 of the laminated battery 2 in the portion 421 of the negative electrode tab 42. It is formed by bending to the side. The bent portions 41 </ b> A and 42 </ b> A are arranged facing the outer sides of the positive electrode tab 41 and the negative electrode tab 42 in the planar direction DR <b> 2 of the laminated battery 2, respectively.

  Referring to FIG. 5C, the positive electrode tab 41 of the laminate type battery 3 has a bent portion 41A, and the negative electrode tab 42 of the laminate type battery 2 has a bent portion 42A. The bent portion 41A is formed by bending a portion 411 of the positive electrode tab 41 to the side opposite to the protruding portion 442 of the laminated battery 2, and the bent portion 42A is formed by bending a portion 421 of the negative electrode tab 42 to the protruding portion 442 of the laminated battery 2. It is formed by bending to the side. The bent portions 41 </ b> A and 42 </ b> A are arranged facing the outer sides of the positive electrode tab 41 and the negative electrode tab 42 in the planar direction DR <b> 2 of the laminated battery 3, respectively.

  1 are the same as the positive electrode tab 41 and the negative electrode tab 42 of the laminated battery 2 shown in FIG. 5B, respectively. Thus, the bent portions 41 </ b> A and 42 </ b> A are provided and are bent in the same manner as the positive electrode tab 41 and the negative electrode tab 42 of the laminated battery 2. 1 are the same as the positive electrode tab 41 and the negative electrode tab 42 of the laminated battery 3 shown in FIG. 5C, respectively. Thus, the bent portions 41 </ b> A and 42 </ b> A are provided and are bent in the same manner as the positive electrode tab 41 and the negative electrode tab 42 of the laminated battery 3. Further, the positive electrode tab 41 of the laminated battery n shown in FIG. 1 has a bent portion 41A in the same manner as the positive electrode tab 41 of the laminated battery 3 shown in FIG. It is bent in the same way as 41. Further, the negative electrode tab 42 of the laminated battery n has a structure in which a part 421 of the negative electrode tab 42 of the laminated battery 3 shown in FIG. 5C is not bent.

  6 is a perspective view of a part of the laminated batteries 1 to 3 and the insulating plates 11 and 12 shown in FIG.

  Referring to FIG. 6, positive electrode tab 41 of laminated battery 1 does not have a bent portion, and negative electrode tab 42 of laminated battery 1 has a bent portion 42 </ b> A (= 421). In each of the laminated batteries 2 and 3, the positive electrode tab 41 has a bent portion 41 </ b> A (= 411), and the negative electrode tab 42 has a bent portion 42 </ b> A (= 421).

  The laminated battery 1 is arranged such that the protruding portion 442 (not shown) faces upward, and the laminated battery 2 has the protruding portion 442 (not shown) of the protruding portion 442 (not shown) of the laminated battery 1. ) And the insulating plate 11 so as to face each other. The laminated battery 3 is disposed via the insulating plate 12 so that the protruding portion 442 faces upward.

  A part 421 of the negative electrode tab 42 of the laminated battery 1 is bent toward the protrusion 442 side of the laminated battery 1 as described above, and a part 411 of the positive electrode tab 41 of the laminated battery 2 is laminated as described above. 2 is bent toward the protruding portion 442. Therefore, when the laminated battery 2 is disposed on the laminated battery 1 so that the protruding portion 442 faces the protruding portion 442 of the laminated battery 1, the bent portion 41A of the positive electrode tab 41 of the laminated battery 2 is The first negative electrode tab 42 is in contact with the bent portion 42A. Then, the bent portion 41A of the positive electrode tab 41 of the laminated battery 2 is welded to the bent portion 42A of the negative electrode tab 42 of the laminated battery 1 using any one of a resistance welder, an ultrasonic welder, and a laser welder. . Thereby, the connection part CN1 is formed.

  Further, as described above, the portion 421 of the negative electrode tab 42 of the laminated battery 2 is bent to the side opposite to the protruding portion 442 of the laminated battery 2, and the portion 411 of the positive electrode tab 41 of the laminated battery 3 is as described above. And bent to the opposite side of the protruding portion 442 of the laminated battery 3. Therefore, when the protruding portion 442 of the laminated battery 2 is disposed downward and the protruding portion 442 of the laminated battery 3 is disposed upward, the bent portion 41A of the positive electrode tab 41 of the laminated battery 3 is It contacts the bent portion 42A of the negative electrode tab 42. Then, the bent portion 41A of the positive electrode tab 41 of the laminated battery 3 is welded to the bent portion 42A of the negative electrode tab 42 of the laminated battery 2 by using any one of a resistance welding machine, an ultrasonic welding machine, and a laser welding machine. . Thereby, the connection part CN2 is formed.

  When the connection portion CN1 is formed, a welding anvil (such as a cradle) is installed between the positive electrode tab 41 and the negative electrode tab 42, and the outside of the in-plane direction DR2 of the laminated batteries 1 and 2 (shown in FIG. 6). The bent portion 41A of the positive electrode tab 41 is welded to the bent portion 42A of the negative electrode tab 42 from the (B direction). Further, when the connection portion CN2 is formed, similarly, a welding anvil (such as a cradle) is installed between the positive electrode tab 41 and the negative electrode tab 42, and the outside of the in-plane direction DR2 of the laminated batteries 2 and 3 is set. The bent portion 41A of the positive electrode tab 41 is welded to the bent portion 42A of the negative electrode tab 42 from (A direction shown in FIG. 6).

  As a result, the negative electrode tab 42 of the laminated battery 3 disposed above the positive electrode tab 41 and the negative electrode tab 42 to be welded does not get in the way. Further, the positive electrode tab 41 of the laminated battery 1 arranged below the positive electrode tab 41 and the negative electrode tab 42 to be welded does not get in the way. Furthermore, since the positive electrode tab 41 and the negative electrode tab 42 have a rectangular shape as described above, the positive electrode tab 41 and the negative electrode tab 42 are not caught when the laminated batteries 1 to 3 are conveyed.

  Therefore, workability can be improved and damage to the positive electrode tab 41 and the negative electrode tab 42 can be prevented.

  The positive electrode tabs 41 of the laminate type batteries 4 to n-1 are welded to the negative electrode tabs 42 of the adjacent laminate type batteries 3 to n-2 by the above-described method, respectively. The tabs 42 are respectively welded to the positive electrode tabs 41 of the laminated batteries 5 to n by the method described above.

  Here, in the connection portion CN1, the bent portion 41A of the positive electrode tab 41 overlaps the bent portion 42A of the negative electrode tab 42 from the outside of the in-plane direction DR2 (the B direction shown in FIG. 6). The bent portion 42A of the negative electrode tab 42 may overlap the bent portion 41A of the positive electrode tab 41 from the outside of the direction DR2 (the B direction shown in FIG. 6). Similarly, in the connection portion CN2, the bent portion 42A of the negative electrode tab 42 may overlap the bent portion 41A of the positive electrode tab 41 from the outside of the in-plane direction DR2 (A direction shown in FIG. 6). The laminated batteries 4 to n-1 may be overlapped similarly.

  FIG. 7 is a side view of the assembled battery 100 as viewed from the direction C shown in FIG. Referring to FIG. 7, laminated batteries 1, 2, laminated batteries 2, 3,..., And laminated batteries n−1, n are respectively insulative plates 11 to n−1 in the stacking direction DR1. Are arranged symmetrically around the center.

  The projecting portions 442 of the laminated batteries 1 and 2 are in contact with the insulating plate 11, the surface opposite to the projecting portions 442 of the laminated batteries 2 and 3 is in contact with the insulating plate 12, and the projecting of the laminated batteries 3 and 4 is performed. The part 442 is in contact with the insulating plate 13, and the surface on the opposite side of the protruding portion 442 of the laminated batteries 4 and 5 is in contact with the insulating plate 14. Similarly, the protrusions 442 of the laminated batteries n-2 and n-1 are in contact with the insulating plate 1n-1, and the surface opposite to the protruding parts 442 of the laminated batteries n-1 and n is the insulating plate. It touches 1n.

  The connection portion CN1 has a structure in which a bent portion 42A of the negative electrode tab 42 of the laminate-type battery 1 and a bent portion 41A of the positive electrode tab 41 of the laminate-type battery 2 are welded, and the connection portion CN2 is a laminate-type battery. 2, the bent portion 42 A of the negative electrode tab 42 and the bent portion 41 A of the positive electrode tab 41 of the laminated battery 3 are welded, and the connecting portion CN 3 is connected to the bent portion 42 A of the negative electrode tab 42 of the laminated battery 3. The bent portion 41A of the positive electrode tab 41 of the laminated battery 4 is welded, and the connecting portion CN4 is connected to the bent portion 42A of the negative electrode tab 42 of the laminated battery 4 and the positive electrode tab 41 of the laminated battery 5. The bent portion 41A has a welded structure. Hereinafter, similarly, the connection part CNn-2 has a structure in which the bent part 42A of the negative electrode tab 42 of the laminated battery n-2 and the bent part 41A of the positive electrode tab 41 of the laminated battery n-1 are welded. Thus, the connection portion CNn-1 has a structure in which the bent portion 42A of the negative electrode tab 42 of the laminate type battery n-1 and the bent portion 41A of the positive electrode tab 41 of the laminate type battery n are welded.

  When the connection portion CN1 is formed, the bent portion 41A of the positive electrode tab 41 has a welding anvil (such as a cradle) arranged in the space SP1 and the negative electrode tab 42 from the outside of the planar direction DR2 (the B direction shown in FIG. 7). It is welded to the bent portion 42A. When the connection portion CN2 is formed, the bent portion 41A of the positive electrode tab 41 has a welding anvil (such as a cradle) disposed in the space SP2 and the negative electrode tab from the outside of the plane direction DR2 (A direction shown in FIG. 7). It is welded to the bent portion 42A of 42. Hereinafter, in the same manner, when the connection parts CN3 to CNn-1 are formed, the bent part 41A of the positive electrode tab 41 has a welding anvil (such as a cradle) disposed in a space between the positive electrode tab 41 and the negative electrode tab 42. And it welds to the bending part 42A of the negative electrode tab 42 from the outer side (A direction or B direction shown in FIG. 7) of the plane direction DR.

  Therefore, when welding the positive electrode tab 41 and the negative electrode tab 42 to be connected, the positive electrode tab 41 and the negative electrode tab 42 other than the positive electrode tab 41 and the negative electrode tab 42 to be connected do not get in the way.

  In addition, in the connection portions CN1, CN3,..., CNn-2, when the bent portion 41A of the positive electrode tab 41 overlaps the bent portion 42A of the negative electrode tab 42 from the outside of the in-plane direction DR2 (the B direction shown in FIG. 7). However, instead of this, the bent portion 42A of the negative electrode tab 42 may overlap the bent portion 41A of the positive electrode tab 41 from the outside of the in-plane direction DR2 (the B direction shown in FIG. 7). Similarly, in the connection portions CN2,..., CNn-1, the bent portion 42A of the negative electrode tab 42 overlaps the bent portion 41A of the positive electrode tab 41 from the outside of the in-plane direction DR2 (A direction shown in FIG. 7). You may do it.

  FIG. 8 is a process diagram showing a method of manufacturing the assembled battery 100 shown in FIG. Referring to FIG. 10, when the production of assembled battery 100 is started, n laminated batteries 1 to n are manufactured (step S1), and n-1 insulating plates 11 to 1n-1 are manufactured. (Step S2).

  Then, a part 421 of the negative electrode tab 42 of the laminated battery 1 is bent by the above-described method, and a part 411 of the positive electrode tab 41 and a part 421 of the negative electrode tab 42 of the laminated battery 2 to n-1 are bent and laminated by the above-described method. A portion 411 of the positive electrode tab 41 of the battery n is bent by the method described above (step S3).

  Thereafter, the laminated batteries 1 to n are stacked via the insulating plates 11 to 1n-1 so that the bent portion 41A of the positive electrode tab 41 is in contact with the bent portion 42A of the negative electrode tab 42 between adjacent laminated batteries. S4).

  Subsequently, between the adjacent laminated batteries, the bent portion 41A of the positive electrode tab 41 is welded to the bent portion 42A of the negative electrode tab 42 from the outside in the planar direction DR2 (step S5). As a result, the assembled battery 100 is manufactured.

  As described above, after laminating batteries 1 to n in which a part 411 of the positive electrode tab 41 and a part 421 of the negative electrode tab 42 are bent are laminated via the insulating plates 11 to 1n-1, a plane is formed between the adjacent laminated batteries. The bent portion 41A (= part 411) of the positive electrode tab 41 is welded to the bent portion 42A (= part 421) of the negative electrode tab 42 from the outside in the direction DR2. As a result, the connecting portions CN1 to CNn-1 are formed all at once without the positive electrode tab 41 and the negative electrode tab 42 other than the positive electrode tab 41 and the negative electrode tab 42 to be connected getting in the way.

  Further, since the positive electrode tab 41 and the negative electrode tab 42 are formed in a rectangular shape, the positive electrode tab 41 and the negative electrode tab 42 are not caught when the laminated batteries 1 to n are conveyed.

  Furthermore, in the laminated batteries 1 to n according to the embodiment of the present invention, the positive electrode tab 41 and the negative electrode tab 42 are provided with the cut lines 412 and 422, and the portion 411 of the positive electrode tab 41 and the portion 421 of the negative electrode tab 42 are bent. However, it is necessary to accurately control the bending position. If the length dimension of each of the bent portions 41A and 42A (the length in the thickness direction of each of the laminated batteries 1 to n) is short, it is impossible to obtain the overlap margin required in the subsequent welding process, and in the worst case, welding is impossible. End up. On the other hand, if the lengths of the bent portions 41A and 42A are too long, there is a high possibility that they will come into contact with the other positive electrode tab 41 and the negative electrode tab 42 after lamination, and in the worst case, a short-circuited state will occur.

  However, in the embodiment of the present invention, as described above, since the distance L2 is set to be shorter than the distance L1, the force for bending the part 411 of the positive electrode tab 41 and the part 421 of the negative electrode tab 42 is linear. The portions 411 of the positive electrode tab 41 and the portion 421 of the negative electrode tab 42 can be bent with high accuracy at the portions along the line segments Ln1 and Ln2.

  Further, in Patent Document 1, since the positive electrode tab and the negative electrode tab have an L-shaped planar shape, the direction of the electrode tab is generated on the equipment surface when the unit cell is manufactured, and the electrode tab is supplied. A discriminating mechanism that discriminates directionality is required. Further, since the protruding portion causes the catch, a relief mechanism is required so that the protruding portion is not caught.

  However, since the positive electrode tab 41 and the negative electrode tab 42 of the laminated batteries 1 to n in the embodiment of the present invention are formed in a rectangular planar shape as described above, the number of materials when the electrode tab is manufactured is improved. As a result, a low-cost electrode tab can be produced. In addition, the discriminating mechanism and the escape mechanism that are necessary when manufacturing the laminated battery in Patent Document 1 are not required.

  Therefore, workability when manufacturing the assembled battery 100 is excellent, and damage to the positive electrode tab 41 and the negative electrode tab 42 can be prevented. Moreover, a short circuit can be prevented.

  In FIG. 8, after laminating all of the laminated batteries 1 to n via the insulating plates 11 to 1 n-1, the bent portion 41 </ b> A of the positive electrode tab 41 is bent between the adjacent laminated batteries. In the embodiment of the present invention, the present invention is not limited to this. However, every time one laminated battery is stacked, the bent portion 41A of the positive electrode tab 41 is welded to the bent portion 42A of the negative electrode tab 42. You may make it perform the process to perform about all the laminated batteries 2-n.

  FIG. 9 is a plan view for explaining another production method for producing the bent portions of the positive electrode tab 41 and the negative electrode tab 42.

  With reference to FIG. 9, a through hole 415 is provided in the positive electrode tab 41. The through hole 415 has a diameter of 1 mmφ, for example. Then, the positive electrode tab 41 is cut from the starting end portion 414 </ b> A located outside the positive electrode tab 41 to the through hole 415 toward the inner side, and a cut line 414 is provided. Thereby, a portion 413 of the positive electrode tab 41 is formed. In this case, the end portion 414B is located closer to the tip end side of the positive electrode tab 41 than the through hole 415. A distance L4 between the start end 414A and the tip end of the positive electrode tab 41 is equal to the distance L1 shown in FIG. 4, and a distance L5 between the end portion 414B and the tip end of the positive electrode tab 41 is shown in FIG. It is equal to the indicated distance L2. Therefore, the distance L5 is shorter than the distance L4.

  Similarly, the through hole 425 is provided in the negative electrode tab 42. The through hole 425 has a diameter of 1 mmφ, for example. Then, the negative electrode tab 42 is cut from the start end portion 424 </ b> A located outside the negative electrode tab 42 to the through hole 425 inward, and a cut line 424 is provided. As a result, a portion 423 of the negative electrode tab 42 is formed. In this case, the terminal end portion 424B is located closer to the tip end side of the negative electrode tab 42 than the through hole 425. The distance L5 between the end portion 424B and the tip of the negative electrode tab 42 is shorter than the distance L4 between the start end 424A and the tip of the negative electrode tab 42.

  When cut lines 414 and 424 are provided in the positive electrode tab 41 and the negative electrode tab 42, respectively, a portion 413 of the positive electrode tab 41 and a portion 423 of the negative electrode tab 42 are bent in the thickness direction of the laminated battery 2 along the line segments Ln3 and Ln4, respectively. The bent portions 41A and 42A described above are produced.

  Also when the through holes 415 and 425 are respectively provided in the positive electrode tab 41 and the negative electrode tab 42 to form the parts 413 and 423 and the formed parts 413 and 423 are bent in the thickness direction of the laminated battery 2, L4> L5 is established. Therefore, the force that bends the portions 413 and 423 concentrates on the portions along the line segments Ln3 and Ln4. Therefore, the portion 413 of the positive electrode tab 41 and the portion 423 of the negative electrode tab 42 can be bent with high accuracy at positions along the line segments Ln3 and Ln4, respectively.

  Parts 413 and 423 are also formed on the positive electrode tab 41 and the negative electrode tab 42 of the laminated batteries 3 to n-1, the negative electrode tab 42 of the laminated battery 1 and the positive electrode tab 41 of the laminated battery n by the method described in FIG. Then, the formed part 413 and / or part 423 is bent in the thickness direction of the laminated batteries 1, 3 to n.

  When forming the bent portions 41A and 42A by forming portions 413 and 423 on the positive electrode tab 41 and the negative electrode tab 42, respectively, the assembled battery 100 is manufactured according to the process diagram shown in FIG. In this case, the portions 411 and 421 in step S3 may be replaced with the portions 413 and 423, respectively.

  FIG. 10 is a schematic view of another assembled battery according to the embodiment of the present invention. The assembled battery according to the embodiment of the present invention may be an assembled battery 100A shown in FIG. Referring to FIG. 10, assembled battery 100A is battery pack 100 shown in FIG. 1 except that positive electrode tab 41 and negative electrode tab 42 of laminated batteries 1 to n are replaced with positive electrode tab 141 and negative electrode tab 142, respectively, and connection terminal 143 is connected. , 144 is added, and the rest is the same as the assembled battery 100.

  Laminated batteries 1 to n are stacked via insulating plates 11 to 1n-1 such that positive electrode tabs 141 and negative electrode tabs 142 are alternately arranged in the stacking direction DR1.

  Each of the positive electrode tab 141 and the negative electrode tab 142 has a rectangular planar shape. The positive electrode tab 141 is made of the same material as the positive electrode tab 41 described above, and the negative electrode tab 142 is made of the same material as the negative electrode tab 42 described above.

  The negative electrode tab 142 of the laminated battery 1 is connected to the positive electrode tab 141 of the laminated battery 2 via the connection terminals 143 and 144. The negative electrode tab 142 of the laminated battery 2 is connected to the positive electrode tab 141 of the laminated battery 3 via the connection terminals 143 and 144. The negative electrode tab 142 of the laminate type battery 3 is connected to the positive electrode tab 141 of the laminate type battery 4 via the connection terminals 143 and 144. The negative electrode tab 142 of the laminate type battery 4 is connected to the positive electrode tab 141 of the laminate type battery 5 via the connection terminals 143 and 144. Similarly, the negative electrode tab 142 of the laminated battery n-2 is connected to the positive electrode tab 141 of the laminated battery n-1 via the connection terminals 143 and 144, and the negative electrode tab 142 of the laminated battery n-1 is connected. Is connected to the positive electrode tab 141 of the laminated battery n via the connection terminals 143 and 144.

  The connection terminal 143 connected to the positive electrode is made of, for example, Ni or the same material as the positive electrode tab 141 connected to the positive electrode, and the connection terminal 14 connected to the negative electrode is made of the same material as the negative electrode tab 142. The connection terminal 143 is welded to the positive electrode tab 141, and the connection terminal 144 is welded to the negative electrode tab 144. The connection terminals 143 and 144 are welded to each other between adjacent laminated batteries. In this case, welding is performed using any one of a resistance welding machine, an ultrasonic welding machine, and a laser welding machine.

  The positive electrode tab 141 of the laminated battery 1 and the negative electrode tab 142 of the laminated battery n are respectively connected to the protection circuit of the battery pack that houses the assembled battery 100A.

  Thus, the assembled battery 100A also has a structure in which n laminated batteries 1 to n are connected in series.

  11 is a perspective view of a part of the laminated batteries 1 to 3 shown in FIG. Referring to (a) of FIG. 11, the connection terminal 144 has an L-shaped cross-sectional shape and has a bent portion 144A. The connection terminal 144 is welded to the negative electrode tab 142 so that the bent portion 144A extends toward the protruding portion 442 of the laminated battery 1. Further, the bent portion 144A is disposed so as to face the outside in the planar direction DR2 of the laminated battery 1. Further, in the laminated battery 1, none of the connection terminals 143 and 144 is welded to the positive electrode tab 141.

  Referring to (b) of FIG. 11, connection terminal 143 has an L-shaped cross-sectional shape and has a bent portion 143A. The connection terminal 143 is welded to the positive electrode tab 141 so that the bent portion 143A extends toward the protruding portion 442 of the laminated battery 2. Further, the bent portion 143A is arranged facing the outside in the planar direction DR2 of the laminated battery 2.

  The connection terminal 144 is welded to the negative electrode tab 142 so that the bent portion 144A extends to the side opposite to the protruding portion 442 of the laminated battery 2. Further, the bent portion 144A is arranged facing the outside in the planar direction DR2 of the laminated battery 2.

  Referring to FIG. 11C, in the laminated battery 3, the connection terminal 143 is welded to the positive electrode tab 141 such that the bent part 143 </ b> A extends to the side opposite to the protruding part 442 of the laminated battery 3. Further, the connection terminal 144 is welded to the negative electrode tab 142 so that the bent portion 144A extends to the protruding portion 442 side of the laminated battery 3. The bent portions 143A and 144A are arranged facing the outside in the planar direction DR2 of the laminated battery 3.

  In the laminated batteries 4, 6,... Shown in FIG. 10, the connection terminals 143, 144 are respectively the same as the connection terminals 143, 144 shown in FIG. Are welded to the positive electrode tab 141 and the negative electrode tab 142. Further, in the laminated batteries 5, 7,... Shown in FIG. 10, the connection terminals 143, 144 are respectively the same as the connection terminals 143, 144 shown in FIG. .. Are welded to the positive electrode tab 141 and the negative electrode tab 142. Further, in the laminated battery n shown in FIG. 10, the connection terminal 143 is welded to the positive electrode tab 141 of the laminated battery n in the same manner as the connection terminal 143 shown in FIG. None of the connection terminals 143 and 144 are welded.

  12 is a perspective view of a part of the laminated batteries 1 to 3 and the insulating plates 11 and 12 shown in FIG.

  Referring to FIG. 12, laminate type batteries 1 and 3 are arranged such that projecting portion 442 faces upward, and laminate type battery 2 has projecting portion 442 (not shown) facing downward. Is arranged.

  The bent portion 144A of the connection terminal 144 welded to the negative electrode tab 142 of the laminated battery 1 extends to the protruding portion 442 side of the laminated battery 1 as described above, and the positive electrode tab 141 of the laminated battery 2 is. As described above, the bent portion 143A of the connection terminal 143 welded to the base terminal 143 extends toward the protruding portion 442 (not shown) of the laminated battery 2. Therefore, when the laminated battery 2 is arranged on the laminated battery 1 so that the protruding portion 442 faces the protruding portion 442 of the laminated battery 1, the connection terminal 143 welded to the positive electrode tab 141 of the laminated battery 2 is bent. The part 143 </ b> A contacts the bent part 144 </ b> A of the connection terminal 144 welded to the negative electrode tab 142 of the laminated battery 1. The bent portion 143A of the connection terminal 143 welded to the positive electrode tab 141 of the laminate type battery 2 is connected to the bent portion 144A of the connection terminal 144 welded to the negative electrode tab 142 of the laminate type battery 1 by resistance welding and ultrasonic welding. Welding is performed using either a welding machine or a laser welding machine. As a result, the connection part CN1 'is formed.

  In addition, the bent portion 144A of the connection terminal 144 welded to the negative electrode tab 142 of the laminated battery 2 is bent to the opposite side to the protruding portion 442 of the laminated battery 2 as described above, and the positive electrode of the laminated battery 3 The bent portion 143A of the connection terminal 143 welded to the tab 141 is bent to the side opposite to the protruding portion 442 of the laminated battery 3 as described above. Therefore, when the protruding portion 442 of the laminated battery 2 is disposed downward and the protruding portion 442 of the laminated battery 3 is disposed upward, the bent portion 143A of the connection terminal 143 welded to the positive electrode tab 141 of the laminated battery 3 is disposed. Is in contact with the bent portion 144A of the connection terminal 144 welded to the negative electrode tab 142 of the laminated battery 2. The bent portion 143A of the connection terminal 143 welded to the positive electrode tab 141 of the laminate type battery 3 is connected to the bent portion 144A of the connection terminal 144 welded to the negative electrode tab 142 of the laminate type battery 2 by resistance welding and ultrasonic welding. Welding is performed using either a welding machine or a laser welding machine. Thereby, the connection part CN2 'is formed.

  When the connection portion CN1 ′ is formed, a welding anvil (such as a cradle) is installed between the positive electrode tab 141 and the negative electrode tab 142, and the outside of the in-plane direction DR2 of the laminated batteries 1 and 2 (see FIG. 12). The bent portion 143A of the connection terminal 143 is welded to the bent portion 144A of the connection terminal 144 from the B direction shown in FIG. Further, when the connection portion CN2 ′ is formed, similarly, a welding anvil (a cradle or the like) is installed between the positive electrode tab 141 and the negative electrode tab 142, and the laminated batteries 2 and 3 are arranged in the in-plane direction DR2. The bent portion 143A of the connecting terminal 143 is welded to the bent portion 144A of the connecting terminal 144 from the outside (A direction shown in FIG. 12).

  As a result, the negative electrode tab 142 of the laminated battery 3 disposed above the positive electrode tab 141 and the negative electrode tab 142 to be connected does not get in the way. Further, the positive electrode tab 141 of the laminated battery 1 disposed below the positive electrode tab 141 and the negative electrode tab 142 to be connected does not get in the way. Furthermore, since the positive electrode tab 141 and the negative electrode tab 142 have a rectangular shape as described above, the positive electrode tab 141 and the negative electrode tab 142 are not caught when the laminated batteries 1 to 3 are conveyed.

  Therefore, workability can be improved and damage to the positive electrode tab 141 and the negative electrode tab 142 can be prevented.

  The positive electrode tabs 141 of the laminate type batteries 4 to n-1 are connected to the negative electrode tabs 142 of the adjacent laminate type batteries 3 to n-2 by the above-described method, respectively. The tabs 142 are respectively connected to the positive electrode tabs 141 of the laminated batteries 5 to n by the method described above.

  Here, in the connection portion CN1 ′, the bent portion 144A of the connection terminal 144 overlaps the bent portion 143A of the connection terminal 143 from the outside of the in-plane direction DR2 (the B direction shown in FIG. 12). The bent portion 143A of the connection terminal 143 may overlap the bent portion 144A of the connection terminal 144 from the outside of the inner direction DR2 (the B direction shown in FIG. 12). Similarly, in the connection portion CN2 ', the bent portion 144A of the connection terminal 144 may overlap the bent portion 143A of the connection terminal 143 from the outside of the in-plane direction DR2 (A direction shown in FIG. 12). The laminated batteries 4 to n-1 may be overlapped similarly.

  13 is a side view of the assembled battery 100A as viewed from the direction C shown in FIG. Referring to FIG. 13, laminated batteries 1 to n are stacked via insulating plates 11 to 1n−1 in the same manner as the stacking method in assembled battery 100.

  The connecting portion CN1 ′ includes a bent portion 144A of the connecting terminal 144 welded to the negative electrode tab 142 of the laminated battery 1 and a bent portion 143A of the connecting terminal 143 welded to the positive electrode tab 141 of the laminated battery 2. The connection portion CN2 ′ has a welded structure, and the connection portion CN2 ′ includes a bent portion 144A of the connection terminal 144 welded to the negative electrode tab 142 of the laminate type battery 2 and a connection terminal 143 welded to the positive electrode tab 141 of the laminate type battery 3. The bent portion 143A is welded, and the connecting portion CN3 ′ is welded to the bent portion 144A of the connection terminal 144 welded to the negative electrode tab 142 of the laminated battery 3 and the positive electrode tab 141 of the laminated battery 4. The connection portion 143 is welded to the bent portion 143A, and the connection portion CN4 ′ is laminated. A bent portion 144A of the connection terminal 144 which is welded to the negative electrode tab 142 of the pond 4, consists of structures folded portion 143A and the positive electrode tab 141 is connected to the connection terminals 143 are welded laminate type battery 5. Hereinafter, similarly, the connection portion CNn-2 ′ is welded to the bent portion 144A of the connection terminal 144 welded to the negative electrode tab 142 of the laminated battery n-2 and the positive electrode tab 141 of the laminated battery n-1. The connecting portion 143A of the connecting terminal 143 is welded to the connecting portion CNn-1 ′, and the connecting portion CNn-1 ′ is connected to the negative electrode tab 142 of the laminated battery n-1 and the bent portion 144A of the connecting terminal 144 is laminated. It has a structure in which the bent portion 143A of the connection terminal 143 welded to the positive electrode tab 141 of the battery n is welded.

  In the case of forming the connection portion CN1 ′, the bent portion 144A of the connection terminal 144 has a welding anvil (such as a cradle) disposed in the space SP3 and the connection terminal 143 from the outside of the plane direction DR2 (the B direction shown in FIG. 13). It is welded to the bent portion 143A. Further, when forming the connection portion CN2 ′, the bent portion 143A of the connection terminal 143 is connected from the outside of the planar direction DR2 (A direction shown in FIG. 13) by arranging a welding anvil (such as a cradle) in the space SP4. It is welded to the bent portion 144A of the terminal 144. Hereinafter, similarly, when the connection portions CN3 ′ to CNn-1 ′ are formed, the bent portion 143A of the connection terminal 143 has a space between the positive electrode tab 141 and the negative electrode tab 142 for the welding anvil (such as a cradle). And welded to the bent portion 144A of the connection terminal 144 from the outside of the planar direction DR (A direction or B direction shown in FIG. 13).

  Accordingly, when the bent portions 143A and 144A of the connection terminals 143 and 144 welded to the positive electrode tab 141 and the negative electrode tab 142 to be connected are welded, the positive electrode tabs 141 other than the positive electrode tab 141 and the negative electrode tab 142 to be connected are connected. The negative electrode tab 142 does not get in the way.

  Further, between the adjacent laminated batteries, the positive electrode tab 141 is connected to the negative electrode tab 142 using the connection terminals 143 and 144. Accordingly, the degree of freedom in terms of the material of the connection terminals 143 and 144 is increased, and welding between the electrode tabs becomes possible with an optimum material configuration for the welding means, and the reliability of the connection portions CN1 ′ to CNn-1 ′ is improved. it can.

  Note that, in the connection portions CN1 ′, CN3 ′,..., CNn-2 ′, the bent portion 144A of the connection terminal 144 is connected to the bent portion 143A of the connection terminal 143 from the outside in the in-plane direction DR2 (B direction shown in FIG. 13). However, instead of this, the bent portion 143A of the connection terminal 143 may overlap the bent portion 144A of the connection terminal 144 from the outside of the in-plane direction DR2 (the B direction shown in FIG. 13). Similarly, in the connection portions CN2 ′, CN4 ′,..., CNn-1 ′, the bent portion 144A of the connection terminal 144 is connected to the connection terminal 143 from the outside in the in-plane direction DR2 (A direction shown in FIG. 13). You may make it overlap with bending part 143A.

  FIG. 14 is a process diagram showing a method of manufacturing the assembled battery 100A shown in FIG. The process diagram shown in FIG. 14 is the same as the process diagram shown in FIG. 8 except that Steps S3 to S5 in the process diagram shown in FIG. 8 are replaced with Steps S3A to S5A, respectively.

  Referring to FIG. 14, when the production of assembled battery 100A is started, the above-described steps S1 and S2 are sequentially executed.

  Then, the connection terminal 144 is welded to the negative electrode tab 142 of the laminate type battery 1, the connection terminals 143 and 144 are welded to the positive electrode tab 141 and the negative electrode tab 142 of the laminate type batteries 2 to n−1, respectively. The connection terminal 143 is welded to the positive electrode tab 141 (step S3A).

  Thereafter, the laminated batteries 1 to n are placed so that the bent part 143A of the connection terminal 143 welded to the positive electrode tab 141 contacts the bent part 144 of the connection terminal 144 welded to the negative electrode tab 142 between adjacent laminated batteries. It laminates | stacks via the insulating plates 11-1n-1 (step S4A).

  Subsequently, the bent portion 143A of the connection terminal 143 is welded to the bent portion 144A of the connection terminal 144 from the outside in the planar direction DR2 between the adjacent laminated batteries (step S5A). Thereby, the assembled battery 100A is completed.

  Thus, between adjacent laminated batteries, the positive electrode tab 141 is connected to the negative electrode tab 142 by welding the bent portion 143A of the connection terminal 143 to the bent portion 144A of the connection terminal 144. Accordingly, the degree of freedom in terms of the material of the connection terminals 143 and 144 is increased, and welding between the electrode tabs becomes possible with an optimum material configuration for the welding means, and the reliability of the connection portions CN1 ′ to CNn-1 ′ is improved. it can. In addition, the assembled battery 100A enjoys the same effects as those described above for the assembled battery 100.

  In the above, a part of the positive electrode tab 41 (or positive electrode tab 141) of the laminated battery 1 is not bent in the thickness direction of the laminated battery 1, and the negative electrode tab 42 (or negative electrode tab 142) of the laminated battery n is not bent. Although it has been described that a portion is not bent in the thickness direction of the laminated battery n, in the embodiment of the present invention, not limited to this, a portion of the positive electrode tab 41 (or the positive electrode tab 141) of the laminated battery 1 is laminated. The battery cell 1 is folded in the thickness direction, and a part of the negative electrode tab 42 (or the negative electrode tab 142) of the laminate battery 1 is not folded in the thickness direction of the laminate battery 1. Alternatively, a part of the negative electrode tab 142) is bent in the thickness direction of the laminated battery n, and the laminated battery n A portion of the positive electrode tab 41 (or positive electrode tab 141) may not be bent in the thickness direction of the laminate type battery n.

  In this case, the display of the positive electrode tab 41 and the negative electrode tab 42 in FIG. 7 may be interchanged. In FIG. 13, the display of the positive electrode tab 141 and the negative electrode tab 142 is interchanged, and the connection terminals 143 and 144 are connected. What is necessary is just to switch a display mutually.

  Therefore, in the embodiment of the present invention, each of the laminated batteries 1 to n includes any one of the first electrode tab including the positive electrode tab 41 and the negative electrode tab 42, and the positive electrode tab 41 and the negative electrode tab 42. Between the adjacent first and second laminated batteries, the bent portion of the first electrode tab of the first laminated battery is a second laminated battery. What is necessary is just to be welded to the bending part of the 2nd electrode tab.

  In the embodiment of the present invention, each of the laminated batteries 1 to n includes any one of the first electrode tab including the positive electrode tab 41 and the negative electrode tab 42, the positive electrode tab 41, and the negative electrode tab 42. A connection terminal (connection terminal 143) welded to the first electrode tab of the first laminated battery between the adjacent first and second laminated batteries. , 144) may be welded to the bent portion of the connection terminal (one of the connection terminals 143, 144) welded to the second electrode tab of the second laminated battery. .

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and is intended to include meanings equivalent to the scope of claims for patent and all modifications within the scope.

  The present invention is applied to an assembled battery.

  1-n laminated battery, 11-1n-1 insulating plate, 41, 141 positive electrode tab, 41A, 42A, 143A, 144A bent portion, 42, 142 negative electrode tab, 43 power generation element, 44 laminate film, 100, 100A assembled battery , 143, 144 Connection terminal, 412, 422 Cut line, 441, 4411 to 4414 Seal part, 442 Protrusion part.

Claims (4)

Each has rectangular first and second electrode tabs having different polarities, and the first electrode tabs and the second electrode tabs are stacked via insulating plates so as to be alternately arranged, And equipped with a plurality of laminated batteries connected in series,
A first score line from the outer side to the inner side in the width direction of the first electrode tab at a desired position from the tip of the first electrode tab of the first laminated battery among the plurality of laminated batteries. A first bent portion having a structure in which a part of the tip side of the first electrode tab with respect to the first cut line is bent in the thickness direction of the laminate-type battery, Providing a second score line from the outer side to the inner side in the width direction of the second electrode tab at a desired position from the tip of the second electrode tab of the second laminated battery adjacent to the battery; An assembled battery that is welded to a second bent portion having a structure in which a part of the tip end side of the second electrode tab is bent in the thickness direction of the laminated battery with respect to a second score line. The distance between the first start end that is the start of the first score line and the tip of the first electrode tab is the distance between the first end that is the end of the first score line and the first end of the first score line. Longer than the distance from the tip of the electrode tab,
The distance between the second start end that is the start of the second score line and the tip of the second electrode tab is the distance between the second end that is the end of the second score and the second end. The assembled battery according to claim 1, wherein the assembled battery is longer than a distance from a tip portion of the electrode tab. Each has rectangular first and second electrode tabs having different polarities, and the first electrode tabs and the second electrode tabs are stacked via insulating plates so as to be alternately arranged, And a plurality of laminated batteries connected in series;
Provided corresponding to the plurality of first electrode tabs, each having a first bent portion facing the outside in the width direction of the first electrode tab and bent in the thickness direction of the laminated battery. And a plurality of first connection terminals welded to corresponding first electrode tabs;
Provided corresponding to the plurality of second electrode tabs, each having a second bent portion that faces the outside in the width direction of the second electrode tab and is bent in the thickness direction of the laminated battery. And a plurality of second connection terminals welded to corresponding second electrode tabs,
The first bent portion of the first connection terminal welded to the first electrode tab of the first laminate battery among the plurality of laminate batteries is a first adjacent to the first laminate battery. The assembled battery welded to the said 2nd bending part of the 2nd connection terminal welded to the 2nd electrode tab of 2 laminated batteries.   The assembled battery according to any one of claims 1 to 3, wherein the first bent portion is welded to the second bent portion by resistance welding or ultrasonic welding.

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