JP2019091522A - Battery pack - Google Patents

Abstract

To quickly detect abnormality due to jet body such as high temperature gas jetted from a battery cell or flame at the time of firing.SOLUTION: A battery pack includes multiple battery cells 1 formed by closing the opening of an outer can 11 with a sealing board 12, a holder case 2 for holding the multiple battery cells 1 in a posture parallel with each other, a pair of bus bar plates 4 placed on the upper and lower surfaces of the holder case 2, a cover member 5 placed on the upper and lower outside of the holder case 2, and covering the bus bar plates 4, and a temperature detector 6 placed between the holder case 2 and the cover member 5. Between the cover member 5 and the holder case 2, an exhaust space 7 into which a jet body flows from the end face of the battery cell 1, when the battery cell 1 is abnormal, is formed. Surroundings of the exhaust space 7 is blocked, and an opening 35 for passing the ejecta is provided by interconnecting a partial region of the surroundings with the outside, and temperature detector 6 is placed closely to the opening 35.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a battery pack in which a plurality of battery cells are stored in a fixed position of a holder case, and more particularly to a battery pack for detecting temperature abnormality of battery cells stored in the battery pack.

  In recent years, power generation using natural energy such as solar light and wind power has attracted attention. These power generation methods are further introduced as a clean power generation method that is environmentally friendly using renewable energy that does not run out of resources compared to power generation methods that use limited fossil fuels such as oil and coal as energy. The spread is expected. However, in this type of power generation, there is a problem that the amount of power generation is affected by the time zone of day and night, the weather, and the like. For this reason, in order to realize stable power supply, the demand for equipment storing the generated power is increasing. In addition, in the case of power generation such as thermal power generation and nuclear power generation as well as power generation by renewable energy, when power generation is continued by rotating the turbine for 24 hours, power generated at midnight is supplied in the daytime when the amount of use increases There is a need for equipment that can store electricity so that it can do it.

  As such a power storage device, a device including a battery pack formed by connecting battery cells such as a lithium ion secondary battery and a nickel hydrogen secondary battery that can be used repeatedly in multiple serial multiple parallel connection is adopted. Among them, lithium ion secondary batteries are widely used in recent years because they are lightweight, have high electromotive force and high energy density. The battery pack can connect a large number of battery cells in series to increase the output voltage, and can also connect in parallel to increase the output current. In particular, due to the recent demand for higher capacity, the number of battery cells to be accommodated tends to increase. However, since the battery cell generates heat when charged and discharged with a large current, it is also important to secure heat dissipation.

  In particular, when an abnormality occurs and the battery cell is further heated, a high temperature gas may be ejected from the inside or may be ejected as a burning flame. In such a case, in a battery pack in which a plurality of battery cells are connected, even if a failure occurs in a part of the battery cells, the other battery cells function normally and can be used as a battery pack. It can be In such a case, burning may spread from the battery cell in which the abnormality has occurred to the adjacent battery cell, and the combustion, smoke, etc. in the battery pack may be further expanded to be in a dangerous state. For this reason, it is necessary to promptly detect and protect the occurrence of an abnormality in some batteries.

JP, 2013-165013, A JP 2014-135247 A

  The present invention has been made in view of such a background, and one of the objects thereof is a battery pack capable of rapidly detecting an abnormality due to a high temperature gas jetted from a battery cell or a jet body such as a flame at the time of ignition. To provide.

Means for Solving the Problems and Effects of the Invention

  In order to achieve the above object, according to the battery pack of the first aspect of the present invention, the plurality of battery cells 1 formed by closing the opening of the cylindrical bottomed outer can 11 with the sealing plate 12 A holder case 2 for holding the plurality of battery cells 1 in parallel with each other and holding the electrode terminals 13 provided on both ends of each battery cell 1 on the same plane; A pair of bus bar plates 4 which are arranged and connected to the electrode terminals 13 of the battery cells 1, a cover member 5 which is arranged outside the upper and lower sides of the holder case 2 and covers the bus bar plate 4, a holder case 2 and a cover A temperature detection unit 6 is disposed between the member 5 and to detect an ambient temperature. Between the cover member 5 and the holder case 2, there is formed a discharge space 7 into which a jetted body jetted from the end face of the battery cell 1 flows when the battery cell 1 is abnormal. The discharge space 7 is closed at the periphery and communicates with a part of the periphery to the outside to provide an opening 35 through which the ejection material passes. The temperature detection unit 6 is provided close to the opening 35. Is placed.

  With the above configuration, when an abnormality occurs in the battery cell stored in the holder case, the temperature detector can reliably pass the ejection body ejected from the end face of the battery cell to detect the temperature abnormality. The battery pack is provided with a discharge space for allowing the discharge from the battery cell to flow between the holder case and the cover member, and the discharge space communicates with a part of the closed periphery to the outside and is open. While providing a part, it is because the temperature detection part is arrange | positioned to this opening part.

  According to the battery pack of the second embodiment of the present invention, the holder case 2 is divided into the first case 2X and the second case 2Y, and the first case 2X and the second case 2Y The end surface plate part 22 in which an end surface is arrange | positioned inside and the surrounding wall 23 formed along the circumference | surroundings of the end surface plate part 22 can be provided. The first case 2X and the second case 2Y form a storage recess 25 for arranging the bus bar plate 4 on the outer surface of the end surface plate portion 22, and close the storage recess 25 with the cover member 5 to form the discharge space 7. be able to.

  According to the above configuration, the first case and the second case are configured by the end face plate portion on which the end face of the battery cell is disposed inside and the peripheral wall formed along the periphery of the end face plate portion The discharge space can be easily formed by closing the storage recess in which the bus bar plate formed on the outer surface is disposed with the cover member. In this structure, the storage recess in which the bus bar plate is arranged is also used as the discharge space, and the cover member which covers the bus bar plate is also used as the member forming the discharge space. Can be reduced.

  According to the battery pack of the third embodiment of the present invention, the battery cells 1 are arranged in the same direction and stored in the holder case 2 and the end plate portion 22 is provided in the first case 2X and the second case 2Y. The penetrating connection hole 24 can be opened to expose the electrode terminal 13 of the battery cell 1 from the connection hole 24, and the electrode terminal 13 can be connected to the bus bar plate 4 to connect a plurality of battery cells 1 in parallel. .

  According to the above configuration, a plurality of battery cells are arranged in the same direction and stored in the holder case, and the electrode terminals of the battery cells are exposed from the connection holes opened in the end plate of the first case and the second case. A plurality of battery cells can be easily connected in parallel by connecting to the bus bar plate.

  Furthermore, according to the battery pack of the fourth embodiment, the holder case 2 can be formed of a thermosetting resin. According to the above configuration, by molding the holder case with a thermosetting resin, excellent heat resistance and chemical resistance can be realized.

  According to the battery pack of the fifth embodiment of the present invention, the opening 35 can be formed in the discharge space 7 opposed to the end of the battery cell 1 where the sealing plate 12 is provided. With the above configuration, an opening is formed in the discharge space facing the end on the side of the sealing plate on which the high temperature gas or the jetted body such as flame is easily discharged at the time of abnormality of the battery cell. It can be detected.

  According to the battery pack of the sixth embodiment of the present invention, one end can be connected to the bus bar plate 4 with the temperature detection unit 6 as a thermal fuse, and the other end can be connected to the outside through the lead wire 76 . According to the above configuration, if any of the battery cells is abnormal and the high temperature gas or flame is discharged, the thermal fuse is melted and the battery voltage can not be detected by the lead wire. Thus, an abnormality of the battery cell can be detected.

It is a perspective view of the battery pack concerning one embodiment of the present invention. It is the II-II sectional view taken on the line of a battery pack shown in FIG. It is the III-III sectional view taken on the line of the battery pack shown in FIG. It is a disassembled perspective view of the battery pack shown in FIG. It is the disassembled perspective view which looked at the battery pack shown in FIG. 4 from lower side. It is a disassembled perspective view of the holder case of the battery pack shown in FIG. It is a disassembled perspective view which shows another example of a holder case. It is a partially expanded disassembled perspective view of a 1st bus-bar plate. It is a partially expanded disassembled perspective view of a 2nd bus-bar plate. It is a principal part expanded sectional view which shows the connection process of a bus-bar plate and a battery cell. It is a schematic plan view which shows the internal structure of the battery pack formed by connecting a several battery pack.

  Hereinafter, embodiments of the present invention will be described based on the drawings. However, the embodiments shown below exemplify a battery pack for embodying the technical concept of the present invention, and the present invention does not specify the battery pack as the following. Further, the present specification does not in any way specify the members described in the claims to the members of the embodiment. In particular, the dimensions, materials, shapes, relative arrangements, and the like of the components described in the embodiments are not intended to limit the scope of the present invention thereto unless specifically described otherwise, but merely illustrative examples It is only Further, in the following description, the same names and reference numerals indicate the same or similar members, and the detailed description will be appropriately omitted. Furthermore, each element constituting the present invention may be configured such that a plurality of elements are constituted by the same member and one member is used in common as a plurality of elements, or conversely, the function of one member is realized by a plurality of members It can be shared and realized.

  The battery pack of the present invention can be used as a power source for a storage-type storage facility, for example, as a storage device for a power plant, a power generation facility, a factory, or a public facility, charged by solar power generation or wind power generation, or midnight The present invention can be applied to a power storage device which is charged by electric power and discharged when necessary. In such an application, a plurality of battery packs can be connected, and these can be connected in series and / or in parallel to increase the output to constitute a power storage device. The power storage device can connect a plurality of battery packs in a series, connect a controller to an end, and control charge / discharge of each battery pack. However, the battery pack of the present invention is not limited to the power supply of such storage equipment, but is used for a street light power supply that charges sunlight during the day and discharges it at night, and for traffic lights and computer servers that are driven at the time of a power failure. It is needless to say that the present invention can also be used as a backup power supply, a backup power supply apparatus for a wireless base station such as a mobile phone, and the like.

  1 to 6 show a battery pack according to an embodiment of the present invention. In these figures, FIG. 1 is a perspective view of the battery pack, FIG. 2 is a sectional view taken along the line II-II of the battery pack of FIG. 1, FIG. 3 is a sectional view taken along the line III-III of the battery pack of FIG. 5 is an exploded perspective view of the battery pack of FIG. 4 viewed from the lower side, and FIG. 6 is an exploded perspective view of the holder case.

  In the battery pack 10 shown in these figures, the plurality of battery cells 1 formed by closing the opening of the cylindrical bottomed outer can 11 with the sealing plate 12 and the plurality of battery cells 11 are in a parallel posture. And the holder case 2 for holding the electrode terminals 13 provided at both ends of each battery cell 1 in the same plane, and the electrode terminals 13 of the battery cells 1 arranged on the upper and lower surfaces of the holder case 2 And a cover member 5 disposed on the upper and lower sides of the holder case 2 and covering the bus bar plate 4, and disposed between the holder case 2 and the cover member 5 to obtain an ambient temperature A temperature detection unit 6 to detect is provided. In the battery pack 10, a discharge space 7 is formed between the cover member 5 and the holder case 2 to allow the jetted body spouted from the end face of the battery cell 1 to flow when the battery cell 1 is abnormal. The discharge space 7 is closed at the periphery and communicates with a part of the periphery to the outside to provide an opening 35 through which the ejection material passes. The temperature detection unit 6 is provided close to the opening 35. Is placed.

(Battery cell 1)
The battery cell 1 is a lithium ion secondary battery that can be charged and discharged. However, the battery cell is not limited to a lithium ion secondary battery, and may be a battery that can be charged and discharged, such as a nickel hydrogen battery or a nickel cadmium battery. Furthermore, although the cylindrical battery is used in the battery pack of the present embodiment, the present invention is not limited to this, and a square battery or a flat battery can also be used.

  As shown in the partially enlarged view of FIG. 6, the battery cell 1 stores the electrode body (not shown) in the cylindrical, bottomed outer can 11 and is filled with an electrolytic solution to open the outer can 11. The part is closed by a sealing plate 12. In the battery cell 1, the bottom surface of the outer can 11, which is both end surfaces, and the sealing plate 12 closed in the insulating state at the opening of the outer can 11 serve as the positive and negative electrode terminals 13.

  The battery cell 1 shown in FIG. 6 is a metal plate formed in the shape of a disc that is concave in the center without increasing the strength by using the outer can 11 as iron or iron alloy and providing the sealing plate 12 with no projecting electrode. You are using Aluminum or an aluminum alloy can be used as such a sealing plate 12. The battery cell 1 of this structure can lower the strength of the aluminum sealing plate 12 with respect to the iron outer can 11. Therefore, when problems such as an abnormally high internal pressure occur due to overcharging or internal short circuit etc., the sealing plate 12 made of aluminum is preferentially opened, and the internal gas etc. is promptly released to the outside. It can be discharged to guarantee safety.

  However, as shown in FIG. 7, the battery cell may have a structure in which the convex electrode 14 is provided on the sealing plate 12. In this battery cell 71, a safety valve (not shown) is provided on the sealing plate 12 and the convex electrode 14, and when the internal pressure of the battery cell 71 rises, the safety valve is opened to exhaust the gas inside. it can.

(Holder case 2)
The holder case 2 shown in FIG. 2, FIG. 3 and FIG. 6 accommodates the plurality of battery cells 1 in a posture parallel to each other. The plurality of battery cells 1 are arranged in the same direction. That is, in the figure, the end on the bottom side of the outer can 11 is disposed downward, and the end closed by the sealing plate 12 is disposed upward. The holder case 2 holds the electrode terminals 13 provided at both ends of each battery cell 1 at a fixed position in a posture in which the electrode terminals 13 are arranged on the same plane.

  As shown in FIG. 6, the holder case 2 is divided into a first case 2X and a second case 2Y in the longitudinal direction of the battery cell 1 and in the middle in the thickness direction. The first case 2 </ b> X and the second case 2 </ b> Y each have a holding portion 21 on the inside for individually inserting and holding the end portions of the cylindrical battery cells 1. The first case 2X and the second case 2Y are an end surface plate portion 22 provided with a plurality of holding portions 21 for inserting the end portion of the battery cell 1 on the inner side surface, and a peripheral wall formed along the periphery of the end surface plate portion 22 It has 23 and. The first case 2 </ b> X and the second case 2 </ b> Y connect the opposing opening edges of the peripheral wall 23 to each other with the overall outer shape being substantially rectangular.

(Holding part 21)
The holding part 21 is formed in the shape which can insert and hold | maintain the edge part of the battery cell 1. The holding portion 21 shown in the figure has a shape along the outer peripheral surface of the battery cell 1, and preferably has a shape that can approach or contact the outer peripheral surface of the battery cell 1 and leave no gap with the outer peripheral surface of the battery cell 1. A plurality of recesses are provided on the inner side of the end surface plate portion 22 as a recess of The plurality of holding portions 21 are formed so as to be able to hold the battery cell 1 inserted therein in a substantially vertical posture with respect to the end surface plate portion 22. Here, since the battery cell 1 uses a cylindrical secondary battery, the holder case 2 forms a holding portion 21 whose inside is formed into a cylindrical shape so that the cylindrical battery cell 1 can be accommodated. . As shown in the exploded perspective view of FIG. 6, these holding portions 21 join the plurality of battery cells 1 by joining the first case 2X and the second case 2Y so as to sandwich the battery cell 1 from both sides. It can be stored at a fixed position inside the holder case 2. However, the holding portion may be a cylindrical portion having an inner shape that follows the outer shape of the battery cell, and a plurality of such cylindrical portions may be arranged.

  The plurality of holding parts 21 are provided in a predetermined arrangement inside of the first case 2X and the second case 2Y. The number of holding portions 21 formed in the holder case 2 is determined by the number of battery cells 1 to be stored. In the present embodiment, the holder case 2 is provided with 76 holding portions 21 in each of the first case 2X and the second case 2Y. The holding portions 21 of the holder case 2 shown in FIG. 6 are formed in nine rows from the first surface 2A to the third surface 2C, and in each row, from the second surface 2B to the fourth surface 2D 8 to 9 are arranged in a straight line at equal intervals, and a total of 76 holding portions 21 are provided. In addition, between the adjacent rows, the holding portions 21 formed in multiple rows are arranged such that the battery cells 1 of the next row are positioned between the adjacent battery cells 1 in one row, that is, in a staggered state The battery cell 1 can be arranged in Here, in the holder case 2 shown in FIG. 6, the battery cell 1 is accommodated in the 76 holding portions 21.

  The depth of the holding portion 21 formed in the concave shape is 5 to 30%, preferably 10 to 25%, and more preferably 15 to 25% of the length of the battery cell 1. Furthermore, the battery cell 1 is joined so as to sandwich the battery cell 1 from both sides by the first case 2X and the second case 2Y, so that both end portions of the battery cell 1 are accommodated and held by the two holding portions 21. The intermediate portion of 1 is exposed to the inside of the holder case 2 to form a hollow portion 20 in the inside of the holder case 2 in which the intermediate portion of the battery cell is exposed. As a result, the battery cells can be separated from each other by the intermediate portions of the battery cells 1 being adjacent to each other, so that the cooling effect of the battery cells can be improved.

  Furthermore, the first case 2 </ b> X and the second case 2 </ b> Y open a connection hole 24 penetrating the bottom surface of the holding portion 21 in the end surface plate portion 22. The end face plate portion 22 exposes the electrode terminal 13 from the connection hole 24 opened in the outer side surface in a state where the end portion of the battery cell 1 is inserted into the holding portion 21 provided inside. Furthermore, as shown in FIG. 2 and FIG. 3, the connection hole 24 is smaller than the outer shape of the outer can 11 of the battery cell 1 inserted into the holding portion 21 to prevent passage of the battery cell 1. . Thus, the end portion of the battery cell 1 inserted into the holding portion 21 can be stopped at a predetermined position of the connection hole 24 without penetrating the end surface plate portion 22. The electrode terminals 13 of the battery cell 1 exposed from the connection holes 24 of the end surface plate portion 22 are connected to the bus bar plate 4 disposed outside the end surface plate portion 22, which will be described later in detail.

  The first case 2 </ b> X and the second case 2 </ b> Y shown in FIGS. 4 to 6 form a storage recess 25 for disposing the bus bar plate 4 on the outer surface of the end surface plate portion 22. In the first case 2X and the second case 2Y shown in the figure, the peripheral wall 23 provided around the end surface plate portion 22 is also protruded to the outside of the end surface plate portion 22 and is formed by this protruding portion and the end surface plate portion 22 The recessed portion thus formed is used as a storage space for the bus bar plate 4 as the storage recess 25. In the holder case 2 shown in the figure, the bus bar plate 4 is disposed in the housing recess 25, and the outside of the housing recess 25 is closed by the cover member 5. The cover member 5 is provided with a side wall 52 along the periphery of the closing plate 51, and the side wall 52 is connected to a peripheral wall 23 projecting to the outside of the holder case 2 to close the periphery of the cover 5 There is.

  Furthermore, although not shown, the holder case 2 can also open a vent in the peripheral wall 23 which is a side surface. As a result, the inside and the outside of the holder case 2 are ventilated, and the heat dissipation characteristics of the battery cell 1 stored in the holder case 2 can be further improved.

(Molding resin)
Such first case 2X and second case 2Y are respectively formed by injection molding using a mold. The holder case 2 is made of a member excellent in insulation, preferably a resin. As such a resin, thermoplastic resins such as PC (polycarbonate), PP (polypropylene), PBT and the like, and thermosetting resins such as unsaturated phenol resin and unsaturated polyester can be used. In the case of a thermosetting resin, it is formed by compression molding or injection compression molding.

  The structure in which the holder case is formed of a thermoplastic resin can simplify the injection molding using a mold and can reduce the manufacturing cost by using an inexpensive thermoplastic resin. However, since the holder case may be heated to a high temperature when the battery cell is abnormal, the holder case may be made of a thermoplastic resin according to the capacity and number of battery cells used, the usage environment, and the required heat resistance performance. it can.

  On the other hand, in the structure in which the holder case 2 is molded with a thermosetting resin, the time for injecting the molten resin into the mold is extended during molding using a mold, and heating and curing are performed after injection. Since the process is required, there is a problem that the mass production can not be efficiently performed in a short time, and there is a problem that the manufacturing cost is increased by using the expensive thermosetting resin. However, in the above battery pack, since the plurality of battery cells 1 are arranged at fixed positions by interposing the positioning spacer 3 between the first case 2X and the second case 2Y constituting the holder case 2, the first Even if the holding portions 21 formed in the case 2X and the second case 2Y are made shallow, it becomes possible to hold the both ends of the battery cell by the holding portions 21 while sandwiching them from both sides. That is, by forming the holding portion 21 into which the end of the battery cell 1 is inserted shallowly, the amount of resin used is reduced while the mold has a simple structure, and the manufacturing time is reduced while the manufacturing time is reduced. It is possible to mass-produce. Further, since the holder case made of thermosetting resin has excellent heat resistance, as described above, even if it is heated to a high temperature by ignition or smoke when the above occurs in the battery cell, it melts. As a result, burning to adjacent battery cells is effectively prevented. Further, since the thermosetting resin is also excellent in chemical resistance, it is possible to prevent the adverse effect of the electrolytic solution and the like discharged from the battery cell. From the above viewpoints, here, a thermosetting resin is preferably used as a resin for producing the holder case.

(Positioning spacer)
The positioning spacer 3 is disposed between the holding portion 21 of the first case 2X and the holding portion 21 of the second case 2Y, and holds the middle portions of the plurality of battery cells 1. Identify the location of The positioning spacer 3 shown in FIG. 6 is a porous plate in which the battery cell 1 is penetrated and a plurality of insertion holes 3A for holding the intermediate portion of the battery cell 1 are opened. The insertion holes 3A opened in the positioning spacer 3 are provided at positions facing the holding portions 21 of the first case 2X and the second case 2Y arranged at the upper and lower sides. Furthermore, the insertion hole 3A has an inner shape in contact with the outer peripheral surface of the battery cell 1 so that the middle portion of the battery cell 1 can be held at a fixed position. The positioning spacer 3 enables the battery cell 1 to be positioned at a fixed position in the holder case 2 by holding an intermediate portion of the battery cell 1 inserted into the insertion hole 3A.

  The above battery pack 10 holds the both ends of the battery cell 1 by the first case 2X and the second case 2Y so as to sandwich the both ends from both sides while positioning the plurality of battery cells 1 with the positioning spacer 3. The plurality of battery cells 1 can be easily inserted into the facing holding portion 21 while being positioned. For example, in a state where the positioning spacer 3 is disposed at the opening of the first case 2X, the battery cell 1 is inserted into the insertion hole 3A of the positioning spacer 3 and the end on the insertion side is the holding portion 21 of the first case 2X. The battery cell 1 can be disposed in the first case 2X while being positioned by being inserted into the first case 2X. In this state, the lower ends of the large number of battery cells 1 arranged in the first case 2X are inserted into the holding portions 21 of the first case 2X, and the middle portions are positioned by the insertion holes 3A of the positioning spacer 3 Therefore, the upper end can be prevented from being easily inserted into the holding portion 21 of the second case 2Y without moving in the front, rear, left, and right. That is, the middle portion of the large number of battery cells 1 arranged in the first case 2X is held at a fixed position by the positioning spacer 3, so that the position of the upper end is positioned and the second case 2Y The upper end portion of the battery cell 1 can be reliably inserted into the holding portion 21 of the second case 2Y in a state of being covered from above. This structure can position and hold the battery cell substantially in the same state as the battery storage unit for storing about half the length of the battery cell 1. Therefore, the end on the opposite side can be immediately inserted into the opposing holding part to hold the both ends of the battery cell 1 so as to be sandwiched from both sides. This can improve the work efficiency at the time of assembly.

  The positioning spacer 3 can easily insert the battery cell 1 by reducing its thickness, and at the same time holding the middle portion of the battery cell 1, the region exposed in the holder case 2 can be widened. it can. Therefore, the thickness of the positioning spacer can be preferably 10% or less of the total length of the battery cell. Such positioning spacer 3 can be made of resin or metal.

  The positioning spacer 3 described above is disposed in the middle of the holder case 2 by being sandwiched between the opposing peripheral walls 23 of the first case 2X and the second case 2Y. In the holder case 2 shown in the figure, the positioning spacer 3 is disposed along the opening edge of the peripheral wall 23 of the first case 2X which is the lower case. This holder case 2 clamps the positioning spacer 3 by the surrounding wall 23 which the 1st case 2X and the 2nd case 2Y oppose, and fixes it to a fixed position. However, the stepped recess can also be provided in the second case. The positioning spacer can also be glued or fixed to the holder case by screwing or locking structures.

  As described above, as shown in FIG. 6, the holder case 2 in which the plurality of battery cells 1 are accommodated is connected to the connection boss 29 provided at the opposing position of the first case 2X and the second case 2Y. 39 is screwed in to fix the first case 2X and the second case 2Y. In the first case 2 </ b> X shown in the drawing, the connection boss 29 is integrally formed on the end surface plate portion 22 and the peripheral wall 23. However, the first case and the second case may be connected to each other through a connection bolt and a nut.

(Other example of holder case)
Furthermore, the holder case can also be configured as shown in FIG. The holder case 72 shown in this figure is divided into a first case 72X and a second case 72Y in the longitudinal direction of the battery cell 71 and in the middle of the thickness direction, and the first case 72X and the second case Between 72Y, the battery holder 70 which inserts the some battery cell 71 and hold | maintains in a fixed position is arrange | positioned. The first case 72X and the second case 72Y shown in FIG. 7 are also formed along the periphery of the end surface plate portion 22 on which the connection terminal 13 which is the end surface of the battery cell 71 is disposed inside and the end surface plate portion 22 A peripheral wall 23 is provided. The entire outer shape of the first case 72X and the second case 72Y is also substantially rectangular, and the opposing opening edges of the peripheral wall 23 are connected to each other.

  The battery holder 70 shown in FIG. 7 has a shape in which a plurality of holding cylinders 73 into which the battery cells 71 are inserted is connected. The battery cells 71 are inserted into the inside of the holding cylinders 73 and the plurality of battery cells 71 are It is arranged in a fixed position in the holder case 72. The battery holder 70 shown in the figure is divided into a plurality of divided units 70A, and these divided units 70A can be individually fixed at fixed positions in the holder case 72. The battery holder 70 is also arranged in the same manner as the above-described holding portion 21 so as to be able to accommodate a plurality of battery cells 72. Such a battery holder can be made of metal such as aluminum or can be made of resin. The metal battery holder can effectively dissipate heat by increasing the heat conduction. A battery holder made of resin can be made lightweight and inexpensive.

(Bus bar plate 4)
Furthermore, the battery pack 10 of FIGS. 2-5 is provided with the bus-bar plate 4 which connects the electrode terminal 13 of the both ends of several battery cells 1 accommodated in holder case 2 in the upper and lower sides of holder case 2 . The bus bar plate 4 is a flat metal plate that covers the outside of the end surface plate portion 22, and a plurality of bus bar plates 4 are connected to connect the electrode terminals 13 of the plurality of battery cells 1 exposed from the connection holes 24 of the end surface plate portion 22. The through hole 40 is opened. These through holes 40 are opened at positions facing the connection holes 24 opened in the end face plate portion 22.

  The bus bar plate 4 is electrically connected to the electrode terminals 13 of the plurality of battery cells 1 housed in the holder case 2. The battery pack 10 shown in the figure is a lower surface side of the first case 2X, which is the lower case of the holder case 2, and a first bus bar plate 4X which is disposed outside the end surface plate portion 22; A second bus bar plate 4Y disposed on the upper surface side of the second case 2Y and outside the end surface plate portion 22 is provided. These bus bar plates 4 have a shape and a size that cover the whole of the end surface plate portion 22 and are sized to be able to connect the electrode terminals 13 of all the battery cells 1 stored in the holder case 2 . The bus bar plate 4 is fixed to the holder case 2 via a set screw (not shown) passing therethrough. This structure can securely fix the bus bar plate 4 to the fixed position of the holder case 2.

  The bus bar plate 4 is connected to the battery cell 1 through the lead plate 45, as shown in FIGS. The lead plate 45 shown in FIGS. 8 and 9 is a thin metal plate and opens the connecting hole 45A at a position facing the through hole 40 of the bus bar plate 4 and is located in the connecting hole 45A. , 47 are equipped. The connection pieces 46 and 47 are integrally connected to the lead plate 45. The lead plate 45 is fixed to the bus bar plate 4 so that the connection pieces 46 and 47 are located in the through holes 40 opened in the bus bar plate 4. The bus bar plate 4 shown in FIGS. 8 and 9 is configured of one lead plate 45.

  In the bus bar plate 4, the connection pieces 46 and 47 of the lead plate 45 are welded to the electrode terminals 13 of the battery cell 1 and are connected to the battery cell 1. Therefore, the connection pieces 46 and 47 are disposed at positions facing the connection terminals 13 exposed from the connection holes 24. The connection pieces 46 and 47 are formed in the shape and the size which are welded to the connection terminal 13 in the state to which the welding rod 60 is pressed, as shown in FIG. Furthermore, the lead plate 45 shown in FIG. 8 forms a fusing part 48 between the opening edge of the connection hole 45A and the connection piece 46. The fusing part 48 shown in the figure is an elongated linear shape formed in a crank shape, and is fused in a state where an overcurrent flows, so that the electrode terminal 13 of the battery cell 1 can be reliably disconnected from the lead plate 45 There is.

  The bus bar plate 4 to which the lead plate 45 is fixed is disposed in a state of being laminated on the outer surface of the end surface plate portion 22 as shown in FIG. 10, and the connection piece 47 of the lead plate 45 is a connection hole of the end surface plate portion 22. Placed at 24. The connection piece 47 disposed in the connection hole 24 is welded to the electrode terminal 13 of the battery cell 1. At the time of welding, as shown in FIG. 10, the welding rod 60 presses and welds the connection piece 47 of the lead plate 45 to the electrode terminal 13 exposed from the connection hole 24 of the end face plate portion 22. Welding rod 60 passes through through hole 40 of bus bar plate 4 and welds connection piece 47 to electrode terminal 13 of battery cell 1. As described above, the electrode terminals 13 at both ends of the plurality of battery cells 1 stored in the holder case 2 are connected to the first bus bar plate 4X and the second bus bar plate 4Y, and thereby the plurality of battery cells 1 are connected in parallel.

  Furthermore, the bus bar plate 4 shown in FIGS. 4 and 5 includes bending pieces 41 and 43 which are bent along the peripheral wall 23 from the outer peripheral edge of the end face plate portion 22, and the tips of the bending pieces 41 and 43 The parts are further bent to form external connection parts 42 and 44. The battery pack 10 shown in FIGS. 1 to 5 is a facing side surface of the holder case 2 having a rectangular outer shape, in which the bending pieces 41 are disposed on the first surface 2A, and the bending pieces are on the third surface 2C. 43 are arranged. By arranging the bent pieces 41 and 43 of the pair of bus bar plates 4 on the opposite side surfaces of the holder case 2 as described above, the bent pieces 41 and 43 are prevented from interfering with each other.

  The first bus bar plate 4 </ b> X arranges the bent pieces 41 along the first surface 2 </ b> A of the holder case 2. The bent piece 41 is formed to rise along the first surface 2A from the lower surface side of the first case 2X, and the tip portion is bent in the horizontal direction to form an external connection portion 42.

  The second bus bar plate 4 </ b> Y arranges the bent pieces 43 along the third surface 2 </ b> C of the holder case 2. The bent piece 43 is formed to hang down from the upper surface side of the second case 2Y along the second surface 2C, and the tip portion is bent in the horizontal direction to form an external connection portion 44. The holder case 2 forms a step surface 28 on which the external connection portion 44 is disposed on the third surface 2C on which the bent piece 43 of the second bus bar plate 4Y is disposed. As described above, by arranging the external connection portion 44 on the step surface 28, the bent piece 43 and the external connection portion 44 are arranged at the fixed position of the holder case 2. Further, the external connection portion 44 can be reliably connected to the outside on the step surface 28.

(Cover member)
Further, as shown in FIGS. 1 to 6, battery pack 10 is located on the upper side and the lower side of holder case 2 to which bus bar plate 4 is fixed, and covers cover member 5 covering bus bar plate 4. Have. The cover member 5 shown in the figure covers and insulates the surface of the bus bar plate 4. The cover member 5 is preferably an insulating member, and is preferably made of resin. Thereby, insulation and weight reduction can be realized at low cost. Further, in consideration of durability and thermal conductivity, a cover member made of metal such as aluminum can also be used. In this case, the surface of the metal cover member may be covered with an insulating member such as a laminate film or vinyl, or an insulating paint may be applied for insulation.

  The cover member 5 has a shape and a size covering the upper and lower surfaces of the holder case 2. The cover member 5 shown in the figure is provided with a flat plate-like closing plate 51 following the inner shape of the holder case 2 and a side wall 52 connected to the periphery of the closing plate 51. The side wall portion 52 is provided with a locking convex portion 54 on the outer peripheral surface, and the locking convex portion 54 is locked to the locking portion 32 provided with the peripheral wall 23 of the holder case 2 and fixed to the holder case 2 I have to. The peripheral wall 23 shown in the figure opens a locking hole as a locking portion 32 for locking the locking convex portion 54. Furthermore, in the holder case 2 shown in FIGS. 2 and 3, the peripheral wall 23 to which the side wall portion 52 is connected has a double wall structure including an outer peripheral wall 23a and an inner peripheral wall 23b. The side wall portion 52 is inserted into a gap formed between the cover member 5 and the holder case 2. The peripheral wall 23 in the figure is formed as the locking portion 32 by opening the above-mentioned locking hole in the outer peripheral wall 23 a. Thus, the cover member 5 can be more firmly fixed to the holder case 2 by forming the connecting portion on the holder case 2 side with a double wall structure of the outer peripheral wall 23a and the inner side wall 23b.

  The cover member 5 shown in FIGS. 2 to 5 is a first cover member 5X which is an outer side of the first case 2X and covers the lower surface side, and an outer side of the second case 2Y and covers the upper surface side. And a second cover member 5Y. The cover member 5 covers the upper surface side of the second case 2Y with the second cover member 5Y so that the battery cell 1 can be interposed between the end plate portion 22 of the second case 2Y and the second cover member 5Y. The discharge space 7 formed facing the end of the sealing plate 12 side of the above is provided.

  The first cover member 5X includes a closing plate portion 51 closing the lower surface side of the first case 2X, and a side wall 52 connected to the periphery of the closing plate portion 51 and closing four side surfaces of the first case 2X. Have. The first cover member 5X shown in FIGS. 4 and 5 connects the side wall portion 52 to the peripheral wall 23 at the second surface 2B, the third surface 2C, and the fourth surface 2D of the holder case 2 to close the first cover member 5X. In the surface 2A, the cover side wall 52A covering the outer side surface of the bent piece 41 of the first bus bar plate 4X is closed close to the bent piece 41. The first cover member 5 </ b> X shown in the figure has the cover side wall 52 </ b> A formed to be high, and can cover the outer side surface of the bent piece 41 with a wide area. As described above, by covering the bent pieces 41 with the cover side wall portion 52A, it is possible to avoid an unintended contact between the first bus bar plate 4X and the outside while arranging the bent pieces 41 in a fixed position. There is.

  Further, the second cover member 5Y is a closing plate portion 51 closing the upper surface side of the second case 2Y, and a side wall portion connected to the periphery of the closing plate portion 51 and closing four side surfaces of the second case 2Y. It has 52. The second cover member 5Y shown in FIGS. 4 and 5 connects the side wall 52 to the peripheral wall 23 at the first surface 2A, the surface 2B, and the fourth surface 2D of the holder case 2 and closes the third surface. On the surface 2C, a rib-like blocking portion 56 for blocking the end edge portion on the bending piece 43 side of the second bus bar plate 4Y is formed to protrude on the inner surface of the blocking plate portion 51. Further, the second cover member 5Y closes the cover side wall 52B covering the outer side surface of the bent piece 43 of the second bus bar plate 4Y by bringing the cover side wall 52B close to the bent piece 43. Further, the second cover member 5Y shown in FIGS. 4 and 5 is provided with a cut-out portion 52C by cutting out the end portion of the cover side wall portion 52B on the second surface 2B side. The cutout 52 </ b> C covers the upper surface of the projecting connection 36 provided on the holder case 2.

(Discharge space 7)
Furthermore, as shown in FIGS. 2 and 3, the battery pack 10 is a holder by closing the storage recess 25 formed on the outside of the end surface plate portion 22 which is the upper and lower surface of the holder case 2 with the cover member 5. A discharge space 7 is formed between the case 2 and the cover member 5 to allow the jetted body jetted from the end face of the battery cell 1 to flow. A bus bar plate 4 is disposed in a discharge space 7 formed between the holder case 2 and the cover member 5. The bus bar plate 4 disposed in the discharge space 7 is stacked on the end surface plate portion 22, and a gap formed between the bus bar plate 4 and the cover member 5 is used as the discharge space 7. The discharge space 7 can have a width of several mm to several cm.

  In the above battery pack 10, when the battery cell 1 is abnormal and is further overheated, a high temperature gas may be ejected from the inside or may be ejected as a burning flame. In such a case, the battery cell 1 is likely to be in a state in which a high-temperature gas, a jet of a flame, or the like is ejected from the sealing plate 12 formed by closing the opening of the outer can 11. Therefore, in the discharge space 7 formed outside the second case 2Y on the side where the sealing plate 12 of the battery cell 1 is disposed, the battery pack 10 has the opening 35 communicating the discharge space 7 to the outside. It is provided. As a result, the high-temperature jetted material discharged from the battery cell 1 in which the abnormality has occurred can be guided to the outside from the opening 35 and discharged.

  The battery pack shown in FIGS. 1 to 5 is the discharge space 7 facing the end of the battery cell 1 provided with the sealing plate 12, and the side wall portion of the discharge space 7 provided on the upper surface side of the holder case 2. The surrounding area is closed via 52, and a partial area of the surrounding area is communicated with the outside without being closed by the side wall 52, so that the ejections discharged from the end face of the battery cell 1 when the battery cell 1 malfunctions An opening 35 is provided. The holder case 2 shown in the figure is in the horizontal direction at a position facing the cutout 52C provided on the second cover member 5Y at a corner (upper right in FIG. 4) of the third surface 2C which is a side surface. A projecting connecting portion 36 is provided, and an opening 35 communicating the discharge space 7 with the outside is provided by partially removing the side wall formed on the upper surface side of the projecting connecting portion 36. In the holder case 2, the upper surface side of the projecting connection portion 36 is closed by the end portion of the closing plate portion 51 in a state where the upper surface side of the second case 2 Y is closed by the second cover member 5 Y The discharge space 7 is communicated with the outside through the opening 35 by arranging the cut-out portion 52C. As shown in FIG. 2, the opening 35 is a sole region for communicating the discharge space 7 whose periphery is closed to the outside, and allows the discharge material discharged from the battery cell 1 in which the abnormality has occurred to pass through to the outside. Discharge.

  Furthermore, in the battery pack 10, a temperature detection unit 6 that detects a temperature abnormality is disposed in the vicinity of the opening 35. The battery pack 10 is a part of the bus bar plate 4, and the temperature detection unit 6 is disposed to face a specific part of the holder case 2. In the holder case 2 shown in the figure, the connection piece 4a of the bus bar plate 4 is disposed on the upper surface of the projecting connection portion 36, and the temperature detection unit 6 is disposed on the upper surface of the connection piece 4a. In the temperature detection unit 6 shown in the figure, when abnormality occurs in any of the battery cells 1 and a high temperature jetted material is discharged from the battery end face or fires, such heat can be reliably detected. It arrange | positions close to the opening part 35 through which the ejection thing ejected from the cell 1 passes.

  In the battery pack 10 shown in FIG. 2, a state where abnormality occurs in any of the battery cells 1 (the battery cell in the central portion in FIG. 2) and the high temperature jetted material is discharged is shown by a dashed line. A state in which a jetted material discharged from the air passes through the discharge space 7 and is discharged to the outside from the opening 35 is indicated by an arrow. As shown in this figure, the ejected material discharged from the battery cell 1 in which the abnormality has occurred flows into the discharge space 7, but the discharge space 7 is closed by the side wall portion 52 and the blocking portion 56. The jetted material is not discharged to the outside from the closed portion, but is discharged to the outside from the opening 35 formed in the cut portion 52C where the side wall 52 is cut. For this reason, the high temperature jetted material flowing into the discharge space 7 surely passes through the opening 35 when being discharged to the outside, and the temperature detection unit 6 disposed close to the opening 35 Temperature anomalies can be detected reliably.

  The second cover member 5Y shown in FIGS. 2 and 4 forms a stepped portion 55 formed by molding the closing plate portion 51 one step lower at the end edge portion on the opening 35 side. Thus, by forming the stepped portion 55 in the second cover member 5Y, the inner surface of the stepped portion 55 is made to approach the temperature detection unit 6, and the jetted material discharged from the discharge space 7 is shown in FIG. As shown, the temperature can be detected reliably by passing it so as to approach the temperature detection unit 6.

(Temperature detection unit 6)
Such a temperature detection unit 6 can use a current interrupting element such as a fuse or a breaker that senses a temperature rise to shut off the current, or a temperature sensor that detects an ambient temperature. When a high temperature gas is discharged from the opening 35, a current blocking element such as a fuse or a breaker is melted by the heat of the high temperature gas, or the movable contact is reversed to cut off the current. The temperature detection unit 6 that is such a current interrupting element can be connected to, for example, a lead that detects the intermediate potential of the battery cell.

  FIG. 11 shows a battery pack 100 provided with a plurality of battery packs 10. The battery pack 100 shown in this figure includes ten battery packs 10. These battery packs 10 are accommodated in an outer case 8 and connected in series. Furthermore, each battery pack 10 is connected with a lead wire 76 for detecting an intermediate potential. As shown in FIG. 4, the temperature detection unit 6, which is a current interrupting element, is connected to the connection piece 4 a of the bus bar plate 4 and has the other end connected to the controller 75 outside the battery pack 10 via the lead wire 76. Connected to In this case, if any of the battery cells 1 stored in the battery pack 10 is abnormal and the high temperature gas or the like is discharged, the current interrupting element operates to disconnect the detection line for detecting the intermediate potential. The controller 75 can not detect the intermediate potential of the battery pack 10 in which the battery cell 1 in which the abnormality has occurred is accommodated. Thereby, the battery pack 10 containing the battery cell 1 which abnormality generate | occur | produced can be identified rapidly.

  Further, a temperature detection unit which is a temperature sensor detects an ambient temperature as a change in resistance value. When the ambient temperature input from the temperature sensor detected by the controller exceeds a predetermined temperature, the temperature detection unit can detect from the detection temperature of the temperature sensor that an abnormality has occurred in any of the battery cells.

  As shown in FIG. 6, the battery pack 10 described above accommodates the battery cells 1 in 76 holding portions 21 provided in the holder case 2. That is, in this battery pack 10, 76 battery cells 1 each having a battery capacity of 4.62 Ah / cell are connected in parallel via the bus bar plate 4 and an output voltage of about 3 V to 4.15 V is large. The battery pack 10 is configured. The number, arrangement, and connection of the battery cells 1 stored in the holder case 2 are not limited to this, and it is needless to say that changes can be made depending on the required voltage and output capacity.

  The present invention is a battery pack in which a plurality of battery cells are housed in a holder case, and can be suitably used as a power source of a storage type storage facility or as a backup power source of various battery devices.

100 battery pack 1 battery cell 2 holder case 2X first case 2Y second case 2A first surface 2B second surface 2C third surface 2D fourth surface 3 positioning spacer 3A insertion Hole 4 ... bus bar plate 4X ... first bus bar plate 4 Y ... second bus bar plate 4 a ... connection piece 5 ... cover member 5 X ... first cover member 5 Y ... second cover member 6 ... temperature detection unit 7 ... discharge space DESCRIPTION OF SYMBOLS 8 ... Outer case 10 ... Battery pack 11 ... Outer can 12 ... Sealing board 13 ... Electrode terminal 14 ... Convex part electrode 20 ... Hollow part 21 ... Holding part 22 ... End surface plate part 23 ... Step difference recessed part 23a ... Outer peripheral wall 23b ... inner peripheral wall 24 ... connection hole 25 ... storage recess 28 ... step surface 29 ... connection boss 32 ... locking portion 35 ... opening 36 ... projecting connection portion 39 ... connection screw 40 ... through hole 41 ... bent piece 42 ... external connection Department DESCRIPTION OF SYMBOLS 3 ... Bent piece 44 ... External connection part 45 ... Lead plate 45A ... Connection hole 46 ... Connection piece 47 ... Connection piece 48 ... Blocking part 51 ... Blocking plate part 52 ... Side wall part 52A ... Cover side wall part 52B ... Cover side wall part 52C ... Cutting portion 54 ... Locking convex portion 55 ... Stepped portion 56 ... Blocking portion 60 ... Welding rod 70 ... Battery holder 70A ... Division unit 71 ... Battery cell 72 ... Holder case 72X ... First case 72Y ... Second case 73 ... Holding Tube 75 ... controller 76 ... lead wire

Claims (6)

A plurality of battery cells formed by closing an opening of a cylindrical bottomed outer can with a sealing plate;
A holder case that holds the plurality of battery cells in parallel with each other and holds the electrode terminals provided at both ends of each battery cell in the same plane;
A pair of bus bar plates disposed on the upper and lower surfaces of the holder case and to which the electrode terminals of the battery cell are connected;
Cover members disposed on upper and lower outer sides of the holder case and covering the bus bar plate;
The battery case is provided with a temperature detection unit disposed between the holder case and the cover member to detect an ambient temperature, and at an abnormal time of the battery cell between the cover member and the holder case, the battery A discharge space is formed to allow the jetted body to be ejected from the end face of the cell.
The discharge space is closed at the periphery and communicates with a part of the periphery to the outside to provide an opening through which the ejection material passes, and the temperature detection unit is disposed close to the opening. Battery pack. A battery pack according to claim 1, wherein
The holder case is divided into a first case and a second case, and the first case and the second case are an end surface plate portion on which an end surface of the battery cell is disposed, and the end surface plate portion And a peripheral wall formed along the periphery,
The first case and the second case form a storage recess for disposing the bus bar plate on the outer surface of the end surface plate portion, and cover the storage recess with the cover member to form the discharge space. Battery pack. A battery pack according to claim 2, wherein
The plurality of battery cells are arranged in the same direction and stored in the holder case.
The first case and the second case open a connection hole passing through the end surface plate portion to expose an electrode terminal of the battery cell from the connection hole and connect the electrode terminal to the bus bar plate A battery pack formed by connecting the plurality of battery cells in parallel. The battery pack according to any one of claims 1 to 3, wherein
A battery pack in which the holder case is formed of a thermosetting resin. The battery pack according to any one of claims 1 to 4, wherein
The battery pack which forms the said opening part in the said discharge space facing the edge part which provided the sealing board of the said battery cell. The battery pack according to any one of claims 1 to 5, wherein
The battery pack in which the temperature detection unit is a thermal fuse, one end is connected to the bus bar plate, and the other end is connected to the outside through a lead wire.

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