Battery

Abstract

Provided is a battery that makes it possible to firmly fix cells to a housing of the battery while increasing the number of cells per unit volume, ultimately contributing to greater energy efficiency.　This battery has a plurality of cells (21) and a housing (3) that houses the plurality of cells (21). Each of the cells (21) is in mutual contact at a side face (21d) thereof with at least one other cell (21), and one end of each cell (21) is fixed to the housing (3) by a fixing means (29).

Description

Battery

[0001] The present invention relates to batteries.

[0002] In recent years, research and development has been conducted on secondary batteries that contribute to energy efficiency in order to ensure that more people have access to affordable, reliable, sustainable, and advanced energy. As a technology related to such secondary batteries, Patent Document 1 discloses a technology for holding multiple cylindrical cells with a negative electrode bus bar. In Patent Document 1, a positioning through-hole is formed in the negative electrode bus bar for each cylindrical cell, and the multiple cylindrical cells are positioned and held by fitting the cylindrical cells into the through-hole. In Patent Document 1, the peripheral edge of the through-hole in the negative electrode bus bar is electrically connected to the case of the cylindrical cell.

[0003] International Publication No. 2021 / 132215

[0004] Increasing the energy density per unit volume is an issue in secondary battery technology. However, the technology described in Patent Document 1 holds cells in the through-holes of the negative bus bar, which tends to create a non-negligible clearance between cells mounted in adjacent through-holes, making it difficult to increase the energy density per unit volume, i.e., the number of cells per unit volume. Furthermore, the technology described in Patent Document 1 also has the issue of low rigidity because the cells are held only by the negative bus bar. The present invention has been made in light of the above-mentioned circumstances, and aims to provide a battery that can increase the number of cells per unit volume while firmly fixing the cells to the battery housing. This, in turn, contributes to energy efficiency.

[0005] The battery has a plurality of cells and a housing that houses the plurality of cells, wherein the cells are in contact with at least one other of the cells at their sides, and one end of the cell is fixed to the housing by a fixing means.

[0006] It is possible to provide a battery in which the number of cells per unit volume can be increased while the cells can be firmly fixed to the battery housing.

[0007] Fig. 1 is a perspective view of a battery unit according to an embodiment. Fig. 2 is a plan view of the battery unit according to an embodiment. Fig. 3 is a plan view showing the arrangement of cells in a cell compressor. Fig. 4 is an exploded perspective view of the cell compressor. Fig. 5 is an exploded perspective view of the battery unit according to an embodiment. Fig. 6 is an explanatory diagram illustrating the operation of the cell compressor in the housing.

[0008] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will now be described with reference to the accompanying drawings. In the drawings, the symbol FR indicates the front, the symbol UP indicates the upper side, and the symbol LH indicates the left side.

[0009] [Embodiment] Fig. 1 is a perspective view of a battery unit 1 according to an embodiment. Fig. 2 is a plan view of the battery unit 1 according to the embodiment. The battery unit (battery) 1 has a battery main body 2 and a housing 3 that houses the battery main body 2. The housing 3 has a box-shaped battery case 4 and a battery cover 5 that closes the opening of the battery case 4. That is, the battery case 4 has a rectangular plate-shaped bottom surface 11 (see Fig. 2), and approximately rectangular plate-shaped front surface 12, rear surface 13, left surface 14, and right surface 15 provided on the front, rear, left, and right sides of the bottom surface 11.

[0010] The battery case 4 accommodates a plurality of cell compartments 20. The cell compartment 20 is a unitized member of a predetermined number of cells (battery cells) 21. The cells 21 are cylindrical. In this embodiment, the longitudinal direction of the cells 21 is referred to as the axial direction. The cells 21 have a positive electrode (positive electrode terminal) 21a (see FIG. 3) and a negative electrode (negative electrode terminal) 21b (see FIG. 3) at one axial end. More specifically, the positive electrode 21a is provided at the axial center of the one axial end of the cell 21. The negative electrode 21b is also provided around the cell 21 and radially spaced from the positive electrode 21a. Between the positive electrode 21a and the negative electrode 21b, an annular recess 21c (see FIG. 3) is formed, recessed toward the other axial side than the positive electrode 21a and the negative electrode 21b.

[0011] In this embodiment, the cells 21 are arranged so that their axial direction is the up-down direction. The cells 21 are arranged adjacent to each other in a direction perpendicular to the up-down direction. The cells 21 are arranged adjacent to each other in a front-rear direction (first direction) and a left-right direction (second direction) perpendicular to the up-down direction (axial direction). The second direction is a direction intersecting the first direction.

[0012] A plate-shaped bus bar 22 is attached to the top surface (one axial end surface) of each adjacently arranged cell 21. The bus bar 22 has a three-layer structure. The bus bar 22 has an insulator 23 (see FIG. 4) in the center in the thickness direction, a positive electrode bus bar 24 (see FIG. 4) above the insulator 23, and a negative electrode bus bar 25 (see FIG. 4) below the insulator 23. The positive electrode 21a of each cell 21 is electrically connected to the positive electrode bus bar 24. The negative electrode 21b of each cell 21 is electrically connected to the negative electrode bus bar 25. This forms a cell comp 20 in which a predetermined number of cells 21 are adjacent to each other. The cell comp 20 is a battery in which a predetermined number of cells 21 are connected in parallel.

[0013] The cell components 20 are fixed to the bottom surface 11 of the battery case 4. In the cell components 20, the lower ends (other axial ends) of each cell 21 are fixed to the upper surface of the bottom surface 11. A plurality of cell components 20 are arranged adjacent to each other. In this embodiment, the cell components 20 are connected in series. That is, the negative electrode bus bar 25 of one cell component 20 is electrically connected to the positive electrode bus bar 24 of the adjacent cell component 20. The shapes of the bus bars 22 of each cell component 20 differ depending on the arrangement position and connection direction, but the basic structure is the same.

[0014] In this embodiment, as shown in Fig. 2, the cell compressors 20 are arranged adjacent to each other in the front-to-rear direction (first direction). The cell compressors 20 are also arranged adjacent to each other in the left-to-right direction (second direction). In this embodiment, a predetermined number of cell compressors 20 are connected in series in two rows in a U-shape. The battery main body 2 of this embodiment is composed of the predetermined number of cell compressors 20 connected in series in two rows.

[0015] As shown in Figure 2, flexible printed circuits (FPCs) 30 are routed above the cell compressor 20 to exchange signals related to the state of the cells 21. The FPCs 30 are electrically connected to the cells 21 and transmit signals related to information about the cells 21. In this embodiment, the FPCs 30 transmit signals related to the temperature and voltage of the cells 21, as examples of information. Therefore, the FPCs 30 include a temperature sensor wiring portion that transmits signals from a temperature sensor that detects the temperature of the cells 21, and a voltage sensor wiring portion that transmits signals from a voltage sensor that measures the voltage of the cells 21.

[0016] The FPC 30 of this embodiment has a pair of FPC main bodies 31 corresponding to two rows of cell comps 20 connected in series in a U-shape. The FPC main bodies 31 extend in the front-to-rear direction. Each FPC main body 31 is arranged so as to overlap one row of cell comps 20 connected in series in a U-shape in a plan view. The FPC main body 31 has an extension 31a extending toward each cell comp 20. The tip of the extension 31a is electrically connected to, for example, the bus bar 22 of each cell comp 20. The pair of FPC main bodies 31 are electrically connected at their front ends to an FPC junction 32 extending in the left-to-right direction. The FPC junction 32 is electrically connected to the connector 28.

[0017] The FPC main body 31 is electrically connected to the connector 28 via the FPC junction 32. Signals related to the temperature and voltage of the cells 21 of each cell compressor 20 are transmitted via the connector 28. A heat-resistant sheet is placed on the underside of the FPC 30 (the surface facing the cell compressor 20) to protect the FPC 30 from the heat of the cells 21.

[0018] FIG. 3 is a plan view showing the arrangement of the cells 21 of the cell comp 20. In the cell comp 20, the cells 21 are arranged such that the cylindrical side surfaces 21d of the cells 21 are in contact with the surrounding cells 21. The cells 21 contact the surrounding cells 21 at position P on the side surfaces 21d. Specifically, three cells 21 are arranged in a straight line in the front-rear direction to form a cell row L21. The cells 21 of the cell row L21 contact each other at position P in the front-rear direction. Six cell rows L21 are arranged in the left-right direction. The cell rows L21 are arranged in six rows in the left-right direction, with the positions of half the cells 21 shifted alternately in the front-rear direction. In adjacent cell rows L21, the cells 21 contact each other at position P in the left-right diagonal direction.

[0019] Therefore, the cells 21 contact each other in a first contact direction D1 extending in the front-to-rear direction, which is the direction of the cell row L21. Furthermore, depending on the arrangement position, the cells 21 contact each other in a second contact direction D2 rotated 60 degrees clockwise in a plan view from the first contact direction D1. Furthermore, depending on the arrangement position, the cells 21 contact each other in a third contact direction D3 rotated 60 degrees clockwise in a plan view from the second contact direction D2. The cells 21 contact each other in at least the second contact direction D2 or the third contact direction D3. Therefore, the cells 21 contact each other in two or more contact directions D1 to D3.

[0020] In this embodiment, the cells 21 are cylindrical. Therefore, the direction of the force exerted by the cells 21 on each other via the side surfaces 21d is the normal direction of the side surfaces 21d. The directions of the force exertion are along the multiple contact directions D1 to D3. Within the housing 3 of the battery unit 1, each cell 21 of the cell comparator 20 is held at its upper end by a bus bar 22 and fixed at its lower end by an adhesive 29. In this embodiment, the rigidity of the cells 21 against stress in the arrangement direction can be easily increased without fixing each cell 21 with a holder or the like. The cells 21 may include tape wrapped around the side surfaces 21d of the cells 21. The tape may be, for example, a film-like material having insulating or heat-insulating properties. If the tape is insulating, it can improve the insulation between the cells 21 that are in contact with each other. If the tape is heat-insulating, it can suppress the transfer of heat generated in a cell 21 to other cells 21 that are in contact with it.

[0021] FIG. 4 is an exploded perspective view of the cell comparator 20. A bus bar 22 is attached to the upper surface (one axial end surface) of each of the cells 21 that are in contact with each other. The negative electrode bus bar 25 of the bus bar 22 is made of metal. The negative electrode bus bar 25 is formed in a plate shape. The negative electrode bus bar 25 of this embodiment is a press-formed product. A circular hole 25a is formed in the negative electrode bus bar 25, penetrating it in the thickness direction. The circular hole 25a is formed in a position corresponding to the positive electrode 21a of each cell 21. Furthermore, a positioning hole 25b is formed in the negative electrode bus bar 25 at a predetermined position, penetrating it in the thickness direction. The positioning hole 25b is formed to have a smaller diameter than the circular hole 25a.

[0022] A ring-shaped series connection portion 25c is formed on the outer peripheral end of the negative bus bar 25. The series connection portion 25c is formed according to the arrangement position of the cell compressor 20. The series connection portion 25c is formed so as to extend in the connection direction of the cell compressor 20. Note that, because adhesive 29 plays a major role in holding the cells 21, the negative bus bar 25 can be made thin so as to reduce electrical resistance.

[0023] The negative electrode bus bar 25 is positioned above the cells 21 so that the positive electrodes 21 a of the cells 21 are exposed through the circular holes 25 a. The negative electrode bus bar 25 is then fixed to the negative electrodes 21 b of the cells 21 by, for example, welding. Examples of welding methods include laser welding and resistance welding. In this way, the negative electrode bus bar 25 is electrically connected to the negative electrodes 21 a of the cells 21.

[0024] The insulator 23 is made of resin. The insulator 23 is formed in a plate shape. A circular hole 23a is formed in the insulator 23, penetrating in the thickness direction. The circular hole 23a is formed at a position corresponding to the positive electrode 21a of each cell 21. A rod-shaped positioning pin 23b that protrudes downward is formed on the lower surface of the insulator 23. The positioning pin 23b is configured to be able to fit into the positioning hole 25b of the negative electrode bus bar 25. A rod-shaped positioning pin 23c that protrudes upward is formed at a predetermined position on the upper surface of the insulator 23.

[0025] The insulator 23 is positioned and placed on the negative bus bar 25 with the positioning pin 23b fitted into the positioning hole 25b of the negative bus bar 25. At this time, the positive electrode 21a of the cell 21 is exposed upward from the circular hole 23a.

[0026] The positive electrode bus bar 24 is made of metal. The positive electrode bus bar 24 is formed in a plate shape. The positive electrode bus bar 24 in this embodiment is a press-formed product. Terminal pieces 24a are formed on the positive electrode bus bar 24 at positions corresponding to the positive electrodes 21a of the cells 21. The terminal pieces 24a are formed in a cut-and-raised shape. The terminal pieces 24a protrude downward relative to the positive electrode bus bar 24. Positioning holes 24b that penetrate the positive electrode bus bar 24 in the thickness direction are formed at predetermined positions. Positioning pins 23c of the insulator 23 can be fitted into the positioning holes 24b.

[0027] A ring-shaped series connection portion 24c is formed on the outer peripheral end of the positive bus bar 24. The series connection portion 24c is formed according to the arrangement position of the cell compressor 20. The series connection portion 24c is formed so as to extend in the connection direction of the cell compressor 20. Like the negative bus bar 25, the positive bus bar 24 can also be made thin so as to reduce electrical resistance.

[0028] The positive bus bar 24 is positioned and stacked on the insulator 23 with the positioning pins 23c of the insulator 23 fitted into the positioning holes 24b. At this time, the terminal pieces 24a come into contact with the positive electrodes 21a of the cells 21 through the circular holes 23a, 25a of the insulator 23 and the negative bus bar 25. The terminal pieces 24a of the positive bus bar 24 are fixed to the positive electrodes 21a by welding, for example. In this way, the positive bus bar 24 is electrically connected to the positive electrodes 21a of each cell 21. In this manner, a three-layered bus bar 22 attached to the top surface of the cell 21 is formed. Furthermore, a predetermined number of cells 21 and the bus bar 22 are integrated to form a cell comparator 20. When resistance welding the bus bar 22 and the cell 21, if insulating tape is wrapped around the side surface 21d of the cell 21, it is possible to prevent part of the welding current from flowing between the cells 21 that are in contact with each other, thereby firmly fixing the bus bar 22 to the cell 21.

[0029] FIG. 5 is an exploded perspective view of a battery unit 1 according to an embodiment. In the battery unit 1 of this embodiment, the battery case 4 has a separable structure. Specifically, the bottom surface 11, left surface 14, and right surface 15 of the battery case 4 are integrally formed, and the front surface 12 and rear surface 13 are separable from these. That is, in this embodiment, the bottom surface 11, left surface 14, and right surface 15 form a case main body 10 having a generally U-shaped cross section. A plate-shaped front surface 12 is fixed to the front surface of the case main body 10. The front surface 12 has multiple terminal ports 12a, 12b and one connector port 12c. A plate-shaped rear surface 13 is fixed to the rear surface of the case main body 10.

[0030] Next, an example of how to assemble the battery unit 1 using the battery case 4, battery cover 5, and cell compressors 20 will be described. A predetermined number of cell compressors 20 are fixed to the case body 10 of the battery case 4. The cell compressors 20 are fixed to the upper surface of the bottom surface 11 of the case body 10 via adhesive 29 (see FIG. 4 ), which is an example of fixing means. At this time, the lower end of each cell 21 of the cell compressor 20 is fixed to the upper surface of the bottom surface 11 via the adhesive 29.

[0031] The cell compressors 20 are fixed in order so as to be connected in series to the existing cell compressors 20. The cell compressors 20 are arranged so as to be connected in series in a U-shape. In the cell compressors 20 connected in series in a U-shape, a positive terminal 26 is electrically connected to the series connection portion 24c of the positive bus bar 24 on one end. In the cell compressors 20 connected in series in a U-shape, a negative terminal 27 is electrically connected to the series connection portion 25c of the negative bus bar 25 on the other end.

[0032] The FPC 30 is attached above the cell comparator 20. The FPC body 31 of the FPC 30 is routed in a predetermined position, and the extension 31 a of the FPC body 31 is welded to the bus bar 22. In this manner, the FPC 30 is attached to the battery body 2.

[0033] A front surface 12 and a rear surface 13 are fixed to the case body 10 to which the battery body 2 is fixed. The front surface 12 and the rear surface 13 are each fixed to the case body 10 via a sealant. Specifically, starting with the rear surface 13, a formed-in-place gasket (FPIG) is applied to the entire longitudinal length of the rear ends of the case body 10, i.e., the rear end of the bottom surface 11, the rear end of the left surface 14, and the rear end of the right surface 15. The rear surface 13 is then abutted against the rear ends of the bottom surface 11, the rear end of the left surface 14, and the rear end of the right surface 15 via the FPIG. The rear surface 13 is fastened to the rear ends of the bottom surface 11, the rear end of the left surface 14, and the rear end of the right surface 15 via fastening members (not shown). The fastening members are, for example, bolts.

[0034] Similarly, FPIG is applied over the entire longitudinal length of the front ends of the case body 10, i.e., the front end of the bottom surface portion 11, the front end of the left surface portion 14, and the front end of the right surface portion 15. The front surface portion 12 is then abutted against the front end of the bottom surface portion 11, the front end of the left surface portion 14, and the front end of the right surface portion 15, respectively, via the FPIG.

[0035] At this time, in the front surface portion 12, the positive terminal 26 is inserted from the rear into the terminal opening 12a. Furthermore, the negative terminal 27 is inserted from the rear into the terminal opening 12b. Furthermore, the connector 28 is inserted from the rear into the connector opening 12c. With the positive terminal 26, the negative terminal 27, and the connector 28 attached, the front surface portion 12 is fastened to the front end of the bottom surface portion 11, the front end of the left surface portion 14, and the front end of the right surface portion 15 via fastening members (not shown). This completes the battery case 4 in which the battery main body 2 and the FPC 30 are housed.

[0036] A battery cover 5 is fixed to the battery case 4 in a state in which the battery main body 2 and FPC 30 are housed. The battery cover 5 is fixed to the battery case 4 via a sealant. Specifically, FPIG is applied to the entire longitudinal direction of the opening of the battery case 4, i.e., the upper end of the front surface 12, the upper end of the rear surface 13, the upper end of the left surface 14, and the upper end of the right surface 15. The battery cover 5 is then abutted against the upper end of the front surface 12, the upper end of the rear surface 13, the upper end of the left surface 14, and the upper end of the right surface 15 via the FPIG. Furthermore, the battery cover 5 is fastened to the upper end of the front surface 12, the upper end of the rear surface 13, the upper end of the left surface 14, and the upper end of the right surface 15 via fastening members (not shown). This forms a sealed housing 3 with the battery case 4 and the battery cover 5. The housing 3 also forms a battery unit 1 in which the battery main body 2 is housed.

[0037] 6 is an explanatory diagram illustrating the operation of the cell compressor 20 inside the housing 3. In this embodiment, the cell 21 has a positive electrode 21a and a negative electrode 21b on the top surface. This allows the power distribution functions, such as the positive electrode bus bar 24 and the negative electrode bus bar 25, to be concentrated on the top surface of the cell 21. Therefore, the bottom end of the cell 21 can be used to fix the cell 21 to the bottom surface 11, and a gas exhaust path S, formed by the circular holes 23a, 25a of the bus bar 22, can be provided above the cell 21.

[0038] Therefore, heat generated in the cells 21 can be transferred downward toward the bottom surface 11 as shown by arrow H1 and dissipated from the bottom surface 11 as shown by arrow H2, ensuring the cooling performance of the cells 21. Furthermore, by consolidating the power distribution function on the top surface of the cells 21, it is easier to reduce the vertical size of the cell compressor 20 compared to when holders or the like are provided at both the top and bottom ends to house and hold the cells.

[0039] In particular, in this embodiment, the lower ends of the cells 21 are fixed to the bottom surface portion 11 via adhesive 29 as fixing means. The longitudinally shaped cells 21 are held at their upper ends by bus bars 22 and fixed at their lower ends by adhesive 29. This makes it possible to increase the rigidity of the cells 21 of the cell comp 20 while maintaining a simple structure. Furthermore, because the structure is one in which the cells are fixed with adhesive 29, the amount of processing required during the manufacture of the cell comp 20 can be reduced, and the cost of manufacturing the cell comp 20 can also be reduced. Note that insulating layers 11a and 11b, which are coated with an insulating material, are formed on both the top and bottom surfaces of the bottom surface portion 11.

[0040] In this embodiment, the cells 21 of the cell comp 20 are in contact with the surrounding cells 21. Therefore, the minimum clearance between the cells 21 is zero. This makes it easier to increase the number of cells per unit volume. In particular, in this embodiment, the cell rows L21 are arranged with alternating offset positions, making it easier to fill gaps between the cells 21 of the cell row L21 with the cells 21 of the adjacent cell rows L21. This makes it easier to reduce the gaps between the cells 21 of the cell comp 20, making it easier to increase the number of cells 21 per unit volume. Furthermore, even when tape is wrapped around the side surfaces 21d of the cells 21, the effect of increasing the number of cells 21 per unit volume can be obtained.

[0041] As described above, according to this embodiment of the present invention, in a battery unit 1 having a plurality of cells 21 and a housing 3 that houses the plurality of cells 21, the cells 21 are in contact with at least one other cell 21 at their side surfaces 21d, and a lower end corresponding to one end of the cell 21 is fixed to the housing 3 by adhesive 29, which is an example of fixing means. This configuration makes it possible to provide a battery unit 1 that can firmly fix the cells 21 to the housing 3 while increasing the number of cells 21 per unit volume.

[0042] In this embodiment, the lower end of the cell 21 is fixed to the housing 3 with adhesive 29. According to this configuration, the cell 21 can be easily fixed to the housing 3.

[0043] In addition, in this embodiment, there are a plurality of contact directions D1, D2, and D3 in which the cells 21 contact each other. With this configuration, the rigidity of the plurality of cells 21 as a whole against stress in the arrangement direction of the cells 21 can be increased.

[0044] In this embodiment, the positive electrode 21a and the negative electrode 21b of the cell 21 are provided at the upper end corresponding to the other end of the cell 21. With this configuration, heat transfer to the housing 3 side is improved.

[0045] Other Embodiments The above-described embodiment merely shows one aspect of the present invention, and any modifications and applications are possible without departing from the spirit of the present invention.

[0046] In the above embodiment, the cells 21 are described as having a cylindrical configuration, but this is not limiting. For example, they may be polygonal tubular. Specifically, for example, if the cells are hexagonal tubular, they can be arranged in contact with each other in the same contact directions D1 to D3 as in the embodiment. Furthermore, for example, if the cells are square tubular, they can be arranged with two contact directions. Furthermore, the cells are not limited to the same shape, and cells of multiple shapes may be used. In other words, a configuration in which cells of multiple shapes are in contact with each other at their side surfaces may be used.

[0047] In the above embodiment, the fixing method using the adhesive 29 has been described as the fixing means, but the fixing means is not limited to adhesive. For example, a protrusion may be provided on the housing 3 and a recess may be provided on the other end of the cell 21, and the protrusion may be press-fitted into the recess to fix the cell to the housing 3.

[0048] [Configurations Supported by the Above-described Embodiments] The above-described embodiments support the following configurations.

[0049] (Configuration 1) A battery having a plurality of cells and a housing for accommodating the plurality of cells, wherein the cells are in contact with at least one other cell at their sides, and one end of each cell is fixed to the housing by a fixing means. With this configuration, the number of cells per unit volume can be increased while the cells are firmly fixed to the battery housing.

[0050] (Configuration 2) The battery according to configuration 1, wherein one end of the cell is fixed to the housing with an adhesive. With this configuration, the cell can be easily fixed to the housing.

[0051] (Configuration 3) The battery according to Configuration 1 or 2, characterized in that the cells are in contact with each other in a plurality of directions. With this configuration, the rigidity of the plurality of cells as a whole against stress in the cell arrangement direction can be increased.

[0052] (Configuration 4) The battery according to any one of configurations 1 to 3, characterized in that the positive and negative terminals of the cells are provided at the other end. With this configuration, heat transfer to the housing side is improved.

[0053] REFERENCE SIGNS LIST 1 Battery unit (battery) 3 Housing 21 Cell 21a Positive electrode (positive electrode terminal) 21b Negative electrode (negative electrode terminal) 21d Side surface 29 Adhesive (fixing means) D1 First contact direction (contact direction) D2 Second contact direction (contact direction) D3 Third contact direction (contact direction)

Claims

1. A battery having a plurality of cells (21) and a housing (3) that houses the plurality of cells (21), characterized in that the cells (21) are in contact with at least one other cell (21) at their side surfaces (21d), and one end of the cells (21) is fixed to the housing (3) by fixing means (29).

2. The battery according to claim 1, wherein one end of the cell (21) is fixed to the housing (3) with an adhesive (29).

3. The battery according to claim 1 or 2, characterized in that there are a plurality of contact directions (D1, D2, D3) in which the cells (21) come into contact with each other.

4. The battery according to claim 1 or 2, wherein the positive terminal (21a) and the negative terminal (21b) of the cell (21) are provided at the other end.

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