JP2014175078A - Battery pack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery pack in which a restrained condition of a plurality of cells stacked in a battery pack can be partially controlled.SOLUTION: A battery pack 100 includes: a line of battery row in which a plurality of battery cells 11 to 15 having a pair of parallel surfaces perpendicular to one direction; at least one positioning plate 21 to 25 arranged at one of the one direction with respect to the battery cells 11 to 15; an urging part 80 for urging the positioning plates 21 to 25 toward the battery cells 11 to 15 in the one direction; and a housing 30 which stores the battery cells 11 to 15 and the positioning plates 21 to 25. The housing 30 has abutting faces 31t to 35t abutted against the positioning plates 21 to 25 which are urged by the urging part 80. The abutting surfaces 31t to 35t are mounted at a position where a compression amount of the battery cells 11 to 15 are predetermined in the one direction.

Description

  The present invention relates to a battery pack in which a plurality of battery cells are connected.

  A battery pack has been proposed in which a plurality of secondary batteries are connected in series or in parallel to be integrated, thereby increasing the output power. In the battery pack, for example, a plurality of battery cells are stacked in a housing to be integrated. On the other hand, a secondary battery may generate gas inside with charge and discharge. Since this gas causes deterioration of the secondary battery, it is preferable to release the gas to the outside of the secondary battery. It is known that the external release of gas can be promoted by pressurization in the stacking direction of the secondary battery. Therefore, it is preferable to pressurize at a suitable pressure in the lamination of the secondary batteries.

  On the other hand, in the secondary battery, a problem has been pointed out in which a plurality of stacked battery cells in the casing expand in the stacking direction and deform the casing during charging and discharging. The deformation of the casing may reduce the pressurizing force in the stacking direction with respect to the secondary battery, thereby hindering smooth external release of gas. For example, the following two methods have been proposed for such problems. The first method uses a compression spring to urge a plurality of battery cells in the stacking direction, thereby absorbing the expansion of the plurality of battery cells and preventing the deformation (creep deformation) of the battery case due to the expansion. (Patent Document 1). The second method uses a bind bar that extends in the stacking direction of the battery stack and restrains it in the stacking direction of the battery stack (Patent Document 2). This bind bar has a stretchable structure that expands and contracts by being partially deformed in the stacking direction. This stretchable structure can be deformed according to the thermal expansion of the members constituting the assembled battery to prevent the generation of an excessive load and maintain proper fastening.

  Furthermore, a method of changing the applied pressure between a charge / discharge state and a non-charge / discharge state in the constraint of the secondary battery has been proposed (Patent Document 3). In this method, electrical characteristics are improved by applying pressure in a charge / discharge state. The improvement of electrical characteristics is realized by reducing the internal resistance by narrowing the relative distance between the plus electrode and the minus electrode by pressurization. On the other hand, in the non-charge / discharge state, the applied pressure is weakened so that the internal resistance can be quickly recovered.

JP 2003-36830 A JP 2011-23302 A JP 2010-9989 A

  However, all of these technologies are intended to integrate a plurality of stacked battery cells, and therefore, there is sufficient study on the restraint state of each of the plurality of battery cells stored in the battery pack. It wasn't done.

  An object of this invention is to provide the battery pack which can control partially the restraint state of the some battery cell laminated | stacked in the battery pack.

  The present invention has been made to solve at least a part of the problems described above, and provides a battery pack. The battery pack includes a row of battery rows in which a plurality of battery cells having a pair of parallel surfaces perpendicular to one direction are stacked, and at least one of the battery cells arranged in one direction with respect to the battery cells. A positioning plate; a biasing portion that biases the positioning plate toward the battery cell in the one direction; and a housing that stores the battery cell and the positioning plate. The housing includes a contact surface that contacts the positioning plate urged by the urging portion. The abutment surface is provided at a position where the compression amount of the battery cell is a preset value in the one direction.

  According to this battery pack, the compression amount of the battery cell can be set to a preset value by the contact surface that contacts the positioning plate biased by the biasing portion. On the other hand, since the positioning plate can be separated from the contact surface, when the battery cell expands excessively, the positioning plate moves to relieve the load applied to the battery cell and to deform the casing. Can be suppressed. Furthermore, when a secondary battery is used for a battery cell in a state where the positioning plate is in contact, the applied pressure increases when the battery cell expands, and the applied pressure decreases when the battery cell expands. Become. As a result, it is possible to improve the performance of the battery cell by changing the applied pressure between the charge / discharge state and the non-charge / discharge state.

  In the above-described battery pack, the positioning plate may include a heat radiating portion protruding from the area of the battery cell.

  If it carries out like this, it can cool effectively in the arbitrary positions of the lamination direction of a some battery cell. As a result, for example, it is possible to solve the problem of heat accumulation in the central portion of a plurality of stacked battery cells, and to quickly eliminate the expansion state and reduce the applied pressure to make the internal resistance recover more quickly. be able to.

  In the above-described battery pack, the positioning plate may be provided for each of the plurality of battery cells, and the contact surface may be in contact with each of the positioning plates.

  In this way, since accumulation of tolerances in the thickness direction of the battery cell does not occur, each pressure state of the battery cell can be accurately managed. Furthermore, when the positioning plate has a heat radiating portion, the temperature of the stacked battery cells can be made uniform by enhancing the heat radiation effect.

  In the above-described battery pack, the urging portion may have a belleville spring to be urged.

  In this way, a large load capacity can be obtained in a relatively small space in the load direction. Thereby, the full length of the lamination direction of the battery pack 100a can be shortened. Furthermore, the disc spring can obtain various load characteristics by appropriately selecting an effective height / plate thickness. In the disc spring, for example, a large initial load can be obtained, but non-linear characteristics such as a small elastic coefficient can be realized when a load exceeding the initial load is applied.

  In the above battery pack, the casing may have a resin main body.

  In this way, by making the main body of the housing made of resin, it is possible to reduce the size and weight of the thin main body without considering the problem of creep deformation. Furthermore, the heat dissipation efficiency is improved by thinning.

ADVANTAGE OF THE INVENTION According to this invention, the pack battery which can control partially the restraint state of the several battery cell laminated | stacked in the battery pack can be provided.

1 is a cross-sectional view showing a configuration of a battery pack 100 according to a first embodiment of the present invention. The graph which shows the relationship between the displacement of the positioning plates 21-25 in the battery pack 100, and a lamination load. Sectional drawing which shows one state of the battery pack 100 in 1st Embodiment of this invention. The disassembled perspective view which shows the structure of the battery pack 100a in 2nd Embodiment of this invention. The longitudinal cross-sectional view which shows the structure of the battery pack 100a in 2nd Embodiment of this invention. Sectional drawing which shows the structure of the battery pack 100b in a modification.

Next, each embodiment of the present invention will be described in the following order. It should be noted that the scope of the present invention is not limited to these forms unless otherwise specified in the following description.
A. Configuration of the battery pack in the first embodiment:
B. Configuration of the battery pack in the second embodiment:
C. Variations:

A. Configuration of the battery pack in the first embodiment:
FIG. 1 is a cross-sectional view showing the configuration of the battery pack 100 according to the first embodiment of the present invention. 1st Embodiment is the simplified structure for demonstrating the working principle of a battery pack. In this configuration, electrical connection is omitted for easy understanding of the description. The battery pack 100 includes five stacked battery cells 11 to 15, five positioning plates 21 to 25, a housing 30, and an urging unit 80. The housing 30 has a main body made of, for example, a nylon or PBT resin, and is formed with a recess 39. The recess 39 stores the stacked battery cells 11 to 15, the positioning plates 21 to 25, and the urging unit 80. The urging unit 80 includes an elastic body such as a spring or rubber, and urges the stacked battery cells 11 to 15 and the positioning plates 21 to 25 in the stacking direction.

  The stacked battery cells 11 to 15 and the positioning plates 21 to 25 are configured as follows, respectively. The stacked battery cells 11 to 15 all have a substantially rectangular parallelepiped shape and have the same configuration. The stacked battery cells 11 to 15 have flat surfaces (not shown) perpendicular to the stacking direction, that is, flat surfaces parallel to each other on both sides. On the other hand, the positioning plates 21 to 25 all have a plate-like shape and the same configuration. The positioning plates 21 to 25 have flat surfaces (not shown) perpendicular to the stacking direction, that is, flat surfaces parallel to each other on both sides. The positioning plates 21 to 25 can be made of an aluminum alloy having good heat transfer characteristics, for example.

  The recessed part 39 of the housing | casing 30 in which the laminated battery cells 11-15 and the positioning plates 21-25 are stored is comprised as follows. The recess 39 is formed as a substantially rectangular parallelepiped recess inside the housing 30. In the substantially rectangular parallelepiped concave portion 39, slits 31 to 35 for inserting the positioning plates 21 to 25 are formed. Each of the slits 31 to 35 is formed as a groove that is continuous over a circumferential position that intersects a plane perpendicular to the stacking direction on the inner surface of the recess 39. Each groove of the slits 31 to 35 has a width (the same width in the present embodiment) larger in the stacking direction than the thickness of the positioning plates 21 to 25. The recess 39 has an inner surface 39t that faces the biasing portion 80.

  The stacked battery cells 11 to 15 and the positioning plates 21 to 25 are fitted and stacked in the recesses 39 of the housing 30 as follows. One flat surface (left side in FIG. 1) of the stacked battery cell 11 is disposed in contact with the inner surface 39t. The positioning plate 21 is arranged such that its flat surface (left side in FIG. 1) abuts on the other flat surface (right side in FIG. 1) of the stacked battery cell 11. At this time, the positioning plate 21 is inserted into the slit 31. The flat surfaces (left side in FIG. 1) of the positioning plates 22 to 25 are disposed in contact with the flat surfaces (right side in FIG. 1) of the stacked battery cells 12 to 15, respectively.

  The fitting state of the stacked battery cells 11 to 15 and the positioning plates 21 to 25 is as follows. The positioning plates 21 to 25 are inserted into the slits 31 to 35, respectively. The slits 31 to 35 have contact surfaces 31t to 35t, respectively. The contact surfaces 31t to 35t are planes perpendicular to the urging direction of the urging unit 80 and are planes facing the urging unit 80 side. The inner surface 39t of the recess 39 is also a plane perpendicular to the urging direction of the urging portion 80 and is a plane facing the urging portion 80 side.

  The distance S between the inner surface 39t and the contact surface 31t in the stacking direction is set shorter than the thickness of the stacked battery cell 11 in the stacking direction by a predetermined distance. On the other hand, the pitch of the five contact surfaces 31t to 35t is set to the same distance S. Thereby, storage spaces shorter by a predetermined distance (the same distance in the present embodiment) than the thicknesses of the stacked battery cells 11 to 15 in the stacking direction are provided for the stacked battery cells 11 to 15, respectively. become.

  The stacked battery cells 11 to 15 and the positioning plates 21 to 25 are urged in the stacking direction by the urging unit 80. As a result, the stacked battery cell 11 is pressed against the inner surface 39t of the recess 39 through the stacked battery cells 12-15 and the positioning plates 21-25. On the other hand, since the positioning plate 21 contacts the contact surface 31t, the positioning plate 21 is stopped at a position of a distance S from the inner surface 39t, and further movement is restrained by the contact surface 31t. As a result, the stacked battery cell 11 is stored in a compressed state (predetermined compression amount) by a predetermined distance. Since the stacked battery cells 11 to 15 have the pitch of the five contact surfaces 31t to 35t set to the distance S, the stacked battery cells 11 to 15 are stored while being compressed by a predetermined distance.

  FIG. 2 is a graph showing the relationship between the displacement of the positioning plates 21 to 25 in the battery pack 100 and the stacking load. FIG. 2 shows two curves of the virtual displacement Dh and the actual displacement Da. The virtual displacement Dh is a virtual displacement assumed when it is assumed that there is no urging by the urging unit 80. The actual displacement Da is an actual displacement in the battery pack 100. Both the virtual displacement Dh and the actual displacement Da are called plate displacements. The contact area and the separation area are virtual displacement areas defined based on the virtual displacement Dh. The contact region is a virtual displacement region in which the positioning plates 21 to 25 are in contact with the contact surfaces 31t to 35t by the initial load of the urging unit 80. The separation region is a virtual displacement region in which the compressive load of the positioning plates 21 to 25 exceeds the initial load and is separated from the contact surfaces 31t to 35t.

  The dotted line Dx indicates the relationship between the stacking load and the virtual displacement when it is assumed that the positioning plate 23 is fixed and has not moved, for example.

  The operation of the battery pack 100 in the contact area is as follows. Since the positioning plates 21 to 25 do not move in the contact area, no change is seen in appearance. However, at the time of charge / discharge, the stacked battery cells 11 to 15 (hereinafter simply described as a representative of the stacked battery cell 11) are caused by the movement of lithium ions. It will expand due to the occurrence. If there is no positioning plates 21 to 25 due to this expansion, the positioning plates 21 to 25 are displaced to the position of the displacement D2 along the virtual displacement Dh. However, since the actual displacement Da is zero, it is in a state of being compressed and elastically deformed. The compressive load at this time is a load F2 that is a value obtained by multiplying the longitudinal elastic modulus in the stacking direction of the stacked battery cells 11 by the displacement D2. That is, if the positioning plate 21 is not present, the stacked battery cell 11 expands in the stacking direction by the displacement D2, but in reality, the expansion is restrained by the positioning plate 21, so the load F2 That is, the compressive load is applied.

  On the other hand, when charging / discharging is completed and non-charging / discharging is performed, cooling is performed, and thermal expansion of the stacked battery cell 11 is reduced, and a small amount of internal gas is discharged. That is, the compressive load at this time decreases to a load F1 that is a value obtained by multiplying the longitudinal elastic modulus in the stacking direction of the stacked battery cells 11 by the displacement D1. Thus, the compressive load increases to the load F2 during charging and discharging, while the compressive load decreases to the load F1 during non-charging and discharging. As a result, at the time of charging / discharging, electrical characteristics can be improved by applying pressure. The improvement of electrical characteristics is realized by reducing the internal resistance by narrowing the relative distance between the plus electrode and the minus electrode by pressurization. On the other hand, in the non-charge / discharge state, the applied pressure is weakened so that the internal resistance can be quickly recovered.

  Furthermore, if the expansion of the stacked battery cell 11 increases due to overcharge or other reasons and the compressive load of the stacked battery cell 11 reaches the load F3, the initial load of the biasing portion 80 is balanced. In this state, the contact load between the positioning plate 21 and the slit 31 is zero. When the compressive load of the stacked battery cell 11 further increases, the positioning plate 21 separates from the contact surface 31t of the slit 31 and starts moving. Thereby, the virtual displacement Dh enters the separation region. However, since the elastic coefficient of the urging portion 80 is significantly smaller than the longitudinal elastic coefficient in the stacking direction of the stacked battery cells 11, the inclination of the virtual displacement Dh in the separation area is larger than the inclination of the virtual displacement Dh in the contact area. It turns out that it is remarkably small. That is, in the contact region, the relationship between the compressive load and the virtual displacement Dh is governed by the longitudinal elastic modulus in the stacking direction of the stacked battery cells 11, whereas in the detached region, the smaller biasing portion 80. It will be governed by the elastic modulus.

  FIG. 3 is a cross-sectional view showing one state of the battery pack 100 according to the first embodiment of the present invention. In this state, the stacked battery cell 13 is excessively expanded due to excessive gas generation due to overcharge or other reasons. In this state, the positioning plate 23 is separated from the contact surface 33t of the slit 33 and moved by the displacement D4. By this displacement D4, the battery pack 100 can absorb the expansion of the stacked battery cell 13 and prevent the generation of an excessive compressive load.

  In the conventional configuration that does not include such a moving mechanism for the positioning plate 23, the compression load rapidly increases along the dotted line Dx if the expansion of the stacked battery cell 13 due to the movement of the positioning plate is not absorbed. Become. This sudden increase in the compressive load causes, for example, creep deformation of the casing, creating a gap between the casing and the stacked battery cell, making it difficult to press the stacked battery cell properly, and smooth internal Inhibits gas release. Furthermore, this gap also caused vibration. In addition, due to the excessive compressive load, it is difficult to extract the stacked battery cells 11 to 15 at the time of abnormality.

  As described above, according to the present embodiment, in the normal operation state, the stacked battery cells 11 to 15 are stored in the space of the width S, and the electrical characteristics are improved by pressurizing at the time of charging / discharging. In the charge / discharge state, the applied pressure is weakened to quickly recover the internal resistance. In other words, the present embodiment can enjoy the advantages of storing the stacked battery cells 11 to 15 in a fixed space having a constant width, while the present embodiment is capable of receiving the stacked battery cells 11 to 11 during abnormal expansion. 15 is allowed to protrude from the space of width S. As a result, it is possible to avoid vibrations caused by a gap generated between the housing and the stacked battery cell or inhibition of internal gas release, and a situation in which it is difficult to extract the stacked battery cells 11 to 15 in an abnormal state. it can.

  Here, the storage state (restraint state) of the stacked battery cells 11 in the contact region is also referred to as a space restraint state because it is spatially restrained. The storage state (restraint state) of the stacked battery cell 11 in the separation region is referred to as a load restraint state because it is restrained by a compressive load.

  In other words, in the present embodiment, the stacked battery cells 11 to 15 are stored in a fixed space (width S) in the contact area, and the stacked battery cells 11 to 15 are biased in the detached area. The load restraint state stored by the urging force of 80 can be automatically switched according to the state of the stacked battery cells 11 to 15. This eliminates the disadvantages of the space restraint state while enjoying the advantages of the above-described space restraint state, while eliminating the disadvantages of the load restraint state while enjoying the advantages of the load restraint state described above.

  Furthermore, when gas is generated inside the stacked battery cells 11 to 15, it is preferable to discharge the internal gas at an early stage by appropriate pressurization. In the present embodiment, the stacked battery cells 11 to 15 are not uniformly pressurized, but the stacked battery cells that are thickened due to the generation of gas inside the area of the abutting region are rapidly increased with a larger applied pressure. The gas can be extracted. On the other hand, with respect to the stacked battery cells in which no gas is generated, the applied pressure is weakened in the non-charge / discharge state to quickly recover the internal resistance. Such an effect is significantly different from the conventional configuration in which the pressure applied to all the stacked battery cells is uniformly increased by the expansion of some of the stacked battery cells.

  The battery pack 100 can be assembled in the following order. First, the housing 30 is prepared. Next, the stacked battery cell 11 is inserted into the recess 39 of the housing 30. The stacked battery cell 11 is arranged on the left side (reference to FIG. 1) of the positioning plate 21 and the positioning plate 21 is inserted into the slit 31. Since the slit 31 has a slit width larger than the thickness of the positioning plate 21, it can be easily inserted. Such assembling work is also performed on the remaining stacked battery cells 12-15 and the positioning plates 22-25. Finally, the urging portion 80 that is constrained in the urging direction and is shortened is inserted into the recess 39, and the constraint is released. Thereby, the five stacked battery cells 11 to 15 and the five positioning plates 21 to 25 are biased. Thus, the battery pack 100 can be easily assembled.

  In this state, the positioning plates 21 to 25 are in contact with the contact surfaces 31t to 35t inside the slits 31 to 35, respectively. Thereby, the positioning plates 21 to 25 can restrain each of the stacked battery cells 11 to 15 to the space of the width S. The space of the width S is set smaller than the size of the stacked battery cells 11 to 15 in the stacking direction. Accordingly, the positioning plates 21 to 25 pressurize each of the stacked battery cells 11 to 15 with a predetermined pressure (the same pressure) as described above.

  Thus, according to the first embodiment, there are various effects such as efficient gas discharge, efficient charging / discharging, and prevention of deformation of the housing 30 of each of the plurality of stacked battery cells 11 to 15. Can do.

B. Configuration of the battery pack in the second embodiment:
FIG. 4 is an exploded perspective view showing the configuration of the battery pack 100a according to the second embodiment of the present invention. FIG. 5 is a longitudinal sectional view showing the configuration of the battery pack 100a according to the second embodiment of the present invention. The second embodiment is a detailed configuration for explaining an example of mounting a battery pack. The battery pack 100a includes eight stacked battery cells 10a, seven positioning plates 20a and 21a, one end plate 28a, a housing 30a, an urging portion 80a, and two types of heat conductive sheets. 41a, 42a, a lid portion 91, an inner lid portion 92, and a circuit board 93. Also in this configuration, electrical connection is omitted for easy understanding of the description.

  The biasing portion 80a uses a disc spring. The disc spring has preferable characteristics with respect to the following embodiment. First, the disc spring can obtain a large load capacity in a relatively small space in the load direction. Thereby, the full length of the lamination direction of the battery pack 100a can be shortened. Second, the disc spring can obtain various load characteristics by appropriately selecting the effective height / plate thickness. In the disc spring, for example, a large initial load and a small elastic coefficient can be achieved for application of a load exceeding the initial load. Specifically, the laminating load F3 in the contact area (see FIG. 2) is set large with a small amount of compression, and the elastic modulus of the separation area is set small, that is, the inclination of the plate displacement Da in the separation area is reduced. Can do.

  The urging portion 80a has a center hole 81a at the center. A protrusion 28h of the end plate 28a is fitted in the center hole 81a (see FIG. 5). The end plate 28a is inserted into a slit 38a formed in the recess 39a of the housing 30a. Thereby, the urging | biasing part 80a is restrained in the direction perpendicular | vertical to the lamination direction with respect to the housing | casing 30a. As a result, the urging portion 80a is restrained in the positional relationship with respect to the housing 30a, and can appropriately apply a load in the stacking direction at the center position of the eight stacked battery cells 10a stacked.

  The stacked battery cell 10a has a substantially rectangular parallelepiped shape, and has the same configuration as the stacked battery cells 11 to 15 in the second embodiment. However, in FIG. 4 and FIG. 5, the stacked battery cell 10 a is drawn up to a unique shape (triangular shape) of the stacked battery cell for taking out the electrodes at the upper and lower positions. In addition, illustration of the electrode is abbreviate | omitted so that a figure may not become complicated.

  The positioning plates 20a and 21a are made of, for example, an aluminum alloy. The positioning plate 20a has a bent portion 20h for heat dissipation. The positioning plate 21a has a bent portion 21h for heat dissipation. The bent portion 20 h is a member for forming a heat radiation path for radiating heat through the inner lid portion 92 and the lid portion 91. The bent portion 21 h is a member for forming a heat dissipation path for radiating heat through the lid portion 91. The bent portions 20h and 21h are also called heat radiating portions.

  The positioning plates 20a and 21a are inserted into the corresponding slits 38a (see FIG. 4). Thereby, each space for storing each of the stacked battery cells 10a is formed. On the other hand, since the seven slits 38a and the end plate 28a are formed at equal intervals of the pitch S as in the first embodiment, each space for storing the stacked battery cell 10a is the first embodiment. Similar to the form, the space has an equal pitch S.

  The positioning plates 20a and 21a are laminated with the thermal conductive sheet 42a interposed (via) between the laminated battery cells 10a. Thereby, the thermal resistance from the stacked battery cell 10a to the positioning plates 20a and 21a is reduced. As described above, the positioning plate may be disposed in contact with the stacked battery cell in the stacking direction as in the first embodiment, or sandwich the heat transfer sheet or the like as in the second embodiment. It may be arranged. That is, the positioning plates 20a and 21a may be arranged in one direction (stacking direction or compression direction) with respect to the stacked battery cell.

  On the other hand, as shown in FIG. 5, the bent portion 20 h is protruded from the region of the stacked battery cell 10 a in the direction of the inner lid portion 92 and approximately 90 in the direction of the urging portion 80 a at a position where it abuts on the inner lid portion 92. It is bent at an angle of degrees. The bent portion 21h is bent at an angle of approximately 90 degrees in the direction of the biasing portion 80a at a position that protrudes from the region of the stacked battery cell 10a in the direction of the lid portion 91 and contacts the lid portion 91. As a result, the contact area with the lid 91 and the middle lid 92 is increased to reduce the thermal resistance.

  The bent portion 20h of the positioning plate 20a is pressed against the inner lid portion 92 with the heat conductive sheet 41a interposed therebetween. The bent portion 21h of the positioning plate 21a and the end plate 28a is pressed against the lid portion 91 with the heat conductive sheet 41a interposed therebetween (via). Thereby, reduction of the thermal resistance between the lid part 91 and the inner lid part 92 is realized. Furthermore, the inner lid portion 92 and the lid portion 91 are both made of a heat conductive resin material, and can provide a good heat dissipation effect.

  As described above, according to the second embodiment, in addition to efficient gas discharge, efficient charge / discharge, prevention of deformation of the housing 30a, each of the plurality of stacked battery cells 10a has efficient heat dissipation. Various effects can be achieved.

  The bent portion 20h may be configured to slide with respect to the inner lid portion 92 or be deformed in accordance with the movement of the positioning plate 20a. The bent portion 21h may be configured to slide with respect to the lid portion 91 in accordance with the movement of the positioning plate 21a or the like, or may be configured to be deformed.

C. Variations:
In the above-described embodiments and examples, a positioning plate is provided for each stacked battery cell. For example, as in the first modification shown in FIG. 6, the number of stacked battery cells and the number of positioning plates are used. May not match. FIG. 6 is a cross-sectional view showing the configuration of the battery pack 100b in the first modification.

  Specifically, compared with the first embodiment, the positioning plates 21 and 23 and the slits 31 and 33 are deleted. Accordingly, in the first modification, one positioning plate 22 is provided for the two stacked battery cells 11 and 12, and one positioning plate 24 is provided for the two stacked battery cells 13 and 14. One positioning plate 25 is provided for one stacked battery cell 15.

  Thus, the ratio between the number of stacked battery cells and the number of positioning plates need not be constant. The battery pack only needs to have a plurality of stacked battery cells and at least one positioning plate disposed between the plurality of battery cells.

  In the above-described embodiments and examples, the initial load of the urging portion is set so that the positioning plate moves when the stacked battery cell expands abnormally, but the positioning plate moves within the normal range. The initial load may be set so as to.

  In the above-described embodiments and examples, laminated (laminate sheet type) lithium ion battery cells are used, but square battery cells that are wound lithium ion battery cells may be used. In the present embodiment, the stacked battery cell has flat surfaces parallel to each other on both sides, but may be any battery cell having a pair of parallel surfaces perpendicular to one direction (stacking direction or compression direction). .

  In the above-described embodiments and examples, a battery array in which a plurality of battery cells are stacked in a line is configured, but a plurality of battery arrays (or) stacked bodies may be configured. In the above-described embodiments and examples, the urging portion is provided at the end of the stacked body, but may be disposed between a plurality of battery cells. Furthermore, at least one battery cell is sufficient and it does not have to be stacked. In this case, since the layers are not stacked, the direction in which the urging portion urges is called the compression direction, not the lamination direction. Thus, the battery pack only needs to have at least one battery cell. Further, the urging portion of the battery pack may be anything that urges the battery cell in the compression direction regardless of the arrangement position.

10a, 11-15 Stacked battery cell 21-25, 20a, 21a Positioning plate 31t-35t Abutting surface 41a, 42a Thermal conductive sheet 80, 80a Biasing portion 80c Belleville spring 91 Lid portion 92 Middle lid portion 93 Circuit board 100 , 100a, 100b, 100c Battery pack

Claims (5)

A battery pack,
A battery row in which a plurality of battery cells having a pair of parallel surfaces perpendicular to one direction are stacked;
At least one positioning plate disposed in one of the one direction with respect to the battery cell;
In the one direction, a biasing portion that biases the positioning plate toward the battery cell,
A housing for storing the battery cell and the positioning plate;
With
The housing has a contact surface that comes into contact with the positioning plate biased by the biasing portion,
The contact surface is a battery pack provided at a position where a compression amount of the battery cell is a preset value in the one direction. The battery pack according to claim 1,
The positioning plate is a battery pack having a heat radiating portion protruding from a region of the battery cell. The battery pack according to claim 1 or 2,
The positioning plate is provided for each of the plurality of battery cells;
The contact surface is a battery pack that contacts each of the positioning plates. The battery pack according to any one of claims 1 to 3,
The biasing part is a battery pack having the disc spring for biasing. The battery pack according to any one of claims 1 to 4,
The casing is a battery pack having a resin main body.