JP6790714B2 - Battery module - Google Patents

Description

The present invention relates to a battery module.

In Patent Document 1, a power storage device group having a plurality of power storage devices arranged in one direction, a pair of restraint members arranged on both sides of the power storage device group, and a pair of restraint members arranged above the power storage device group are arranged. Described is a power storage device module comprising a cover fixed to a pair of restraint members and a temperature sensor mounted on the upper surface of the power storage device to detect the temperature of the power storage device. In this power storage device module, an expansion absorption unit that absorbs the expansion of the power storage device is arranged on any one side of the pair of restraint members. Further, the cover is equipped with a holding portion that holds the temperature sensor against the power storage device.

JP-A-2016-122575

In the above power storage device module, the distance from the opposite end of the expansion / absorption unit of the temperature sensor to the holding portion is moved toward the expansion / absorption unit side by the expansion of the plurality of power storage devices in the power storage device on which the temperature sensor is mounted. It is longer than the quantity. As a result, in this power storage device module, even if the temperature sensor moves to the expansion / absorption unit side due to the expansion of the power storage device, the temperature sensor is maintained in a state of being pressed against the power storage device by the holding unit. As described above, in the above technical field, it is desired that the temperature sensor is reliably pressed against the temperature measuring cell, which is the battery cell provided with the temperature sensor, regardless of the expansion of the battery cell.

An object of the present invention is to provide a battery module capable of reliably pressing a temperature sensor against a temperature measuring cell.

The battery module according to the present invention has a main surface and electrode terminals provided on the main surface, and a plurality of battery cells stacked on each other along a first direction and a plurality of battery cells individually holding the battery cells. A holder, a restraint portion for restraining a plurality of battery cells along the first direction, a temperature sensor provided on the main surface of at least one battery cell, and a temperature measuring cell which is a battery cell provided with a temperature sensor. A first cover, which is arranged to face the main surface so as to cover at least two adjacent battery cells including the battery cell, is provided, and the first cover is a pressing force for pressing the temperature sensor against the temperature measuring cell. It has a portion and a positioning portion for positioning in the first direction with respect to a holder that holds the temperature measuring cell.

In this battery module, the first cover has a pressing portion for pressing the temperature sensor against the temperature measuring cell and a positioning portion for positioning the holder holding the temperature measuring cell in the first direction. .. As a result, when the battery cell expands, the holder holding the temperature measuring cell and the first cover move integrally in the first direction. Therefore, the relative movement between the pressing portion of the first cover and the temperature sensor on the temperature measuring cell side is suppressed. As a result, the state in which the temperature sensor is pressed against the temperature measuring cell by the pressing portion of the first cover is maintained. That is, according to this battery module, the temperature sensor can be reliably pressed against the temperature measuring cell.

In the battery module according to the present invention, the holder holding the temperature measuring cell includes the first intersection surface intersecting in the first direction, and the first cover includes the second intersection surface intersecting in the first direction and is positioned. The portion may be positioned by abutting the first intersection surface and the second intersection surface. In this case, the first intersection surface of the holder and the second intersection surface of the first cover abut each other in the first direction, so that the holder holding the temperature measuring cell can be positioned in the first direction of the first cover. Become.

In the battery module according to the present invention, the holder holding the temperature measuring cell has a protrusion protruding on the first cover, the first intersecting surface is the outer surface of the protrusion, and the positioning portion is in the first direction. It has a pair of engaging claws that engage the protrusions from both sides of the protrusion, and the second intersecting surface may be the inner surface of the pair of engaging claws that face the outer surface. In this case, the outer surface of the protrusion of the holder that holds the temperature measuring cell and the inner surface of the pair of engaging claws of the first cover have a simple structure in which they abut each other on both sides of the first direction (opposite the first direction and the first direction). Positioning in the direction) is possible.

In the battery module according to the present invention, the first cover has a facing surface facing the main surface and an opposite surface extending along the main surface on the opposite side of the facing surface, and the protrusion contacts the opposite surface. The contact surface may be included. In this case, since the protrusion of the holder contacts the opposite surface of the first cover on its contact surface, it is possible to restrict the movement of the first cover so as to be separated from the main surface.

The battery module according to the present invention may further include a second cover arranged so as to be adjacent to the first cover along the first direction and facing the main surface. In this case, by arranging the second cover according to the number of battery cells in the battery module, the first cover and the second cover can surely cover and protect the battery cells.

In the battery module according to the present invention, the first cover may have an overlapping portion overlapping with the second cover along the direction intersecting the main surface. In this case, even if the holder and the first cover move along the first direction due to the expansion of the battery cell, the first cover and the first cover and the first cover and the first cover and the first cover overlap within the overlapping portion of the first cover and the second cover. The second cover keeps the battery cell covered.

The battery module according to the present invention may further include an elastic member constrained together with the battery cell along the first direction. In this case, even if the battery cell expands and the battery cell moves along the first direction, the load due to the expansion of the battery cell can be absorbed, for example, by crushing the elastic member. Further, at this time, since the movement of the battery cell along the first direction becomes relatively large, the effect of positioning the first cover by the positioning portion becomes remarkable.

According to the present invention, it is possible to provide a battery module capable of reliably pressing a temperature sensor against a temperature measuring cell.

FIG. 1 is a perspective view showing the overall configuration of the battery module according to the embodiment. FIG. 2 is a cross-sectional view of the battery module shown in FIG. 1 along lines II-II. FIG. 3 is a cross-sectional view of the battery cell shown in FIG. 1 along a plane orthogonal to the first direction. FIG. 4 is a perspective view of the battery cell and holder shown in FIG. FIG. 5 is a cross-sectional view of the battery module shown in FIG. 1 along a plane orthogonal to the first direction. FIG. 6 is a perspective view of the first cover shown in FIG. FIG. 7 is a cross-sectional view showing a relative position change between the pressing portion and the thermistor in the battery module according to the comparative example. FIG. 8 is a cross-sectional view showing a relative position change between the pressing portion and the thermistor in the battery module shown in FIG.

Hereinafter, one embodiment will be described with reference to the drawings. In the description of the drawings, the same elements are designated by the same reference numerals, and duplicate description will be omitted. The dimensional ratios in the drawings do not always match those described. Further, in the explanation, the words indicating the directions such as "up" and "down" are convenient words based on the state shown in the drawing. For convenience of explanation, each figure has an X-axis, a Y-axis, and a Z-axis that are orthogonal to each other.

The battery module 10 according to the embodiment will be described. As shown in FIGS. 1 and 2, the battery module 10 includes a plurality of battery cells 11 such as, for example, a lithium ion secondary battery or a nickel hydrogen storage battery. In this embodiment, as an example, the number of battery cells 11 is 13. Each of the plurality of battery cells 11 is laminated with each other along the first direction (for example, the X-axis direction) while being individually held by the plurality of holders 21. That is, the battery module 10 includes a plurality of holders 21 that individually hold the battery cells 11.

A pair of end plates (constraining portions) 12A and 12B are provided at both ends of the laminated body of the battery cells 11 in the first direction. An intermediate plate 15 is arranged between the laminate and the end plate 12A. Further, an elastic member 17 made of an elastic material such as rubber or sponge is arranged between the intermediate plate 15 and the end plate 12A.

Bolts B are inserted through the pair of end plates 12A and 12B, the intermediate plate 15, and the holder 21. The bolt B is inserted so as to be bridged from one end plate 12A to the other end plate 12B, and is screwed to the nut N on the other end plate 12B side. Therefore, the pair of end plates 12A and 12B restrain the plurality of battery cells 11 together with the elastic member 17 along the first direction. That is, the battery module 10 includes end plates 12A and 12B that restrain a plurality of battery cells 11 along the first direction, and an elastic member 17 that is restrained together with the battery cells 11 along the first direction.

As shown in FIGS. 3 and 4, the battery cell 11 electrically attaches to the electrode assembly 52, the case 51 accommodating the electrode assembly 52, and the electrodes (positive electrode and negative electrode, respectively) of the electrode assembly 52. It has a pair of electrode terminals 55 that are connected and project from the case 51.

The case 51 is composed of a box-shaped main body 53 that houses the electrode assembly 52 and a plate-shaped lid 54 that closes the opening of the main body 53. Electrode terminals 55 (positive electrode terminal and negative electrode terminal) are provided on the upper surface (main surface) 54A of the lid portion 54. The electrode terminal 55 is electrically connected to the electrode assembly 52 via the conductive member 58. That is, the battery cell 11 has an upper surface 54A and an electrode terminal 55 provided on the upper surface 54A.

The electrode assembly 52 includes a plurality of positive electrodes (not shown) and negative electrodes (not shown), and a separator (not shown) arranged between the positive electrode and the negative electrode. The positive electrode and the negative electrode are alternately laminated via a separator. The stacking direction of the positive electrode and the negative electrode is substantially the same as the stacking direction of the battery cell 11 (first direction: X-axis direction).

The upper surface 54A of the lid portion 54 is provided with an opening valve 57 that breaks and releases the internal pressure of the case 51 when the internal pressure of the case 51 rises to a threshold value. The threshold value is set so that when the internal pressure of the case 51 increases, the release valve 57 breaks before the case 51 is damaged by the internal pressure of the case 51.

As shown in FIG. 4, the holder 21 has a rectangular flat plate-shaped bottom wall portion 22, a side wall portion 23, a side wall portion 24, a back surface portion 25, a pair of extending portions 26, a pair of projecting portions 29, and a pair of terminals. It has an accommodating portion 31 and a pair of projecting portions 33.

The bottom wall portion 22 is a portion that covers the bottom surface of the battery cell 11 (the surface opposite to the upper surface 54A) when the battery cell 11 is held. The side wall portion 23 and the side wall portion 24 are arranged so as to face each other at both ends of the bottom wall portion 22 in the second direction (for example, the Y-axis direction) intersecting in the first direction, and intersect in the first direction and the second direction. It extends along a third direction (for example, the Z-axis direction). The side wall portion 23 and the side wall portion 24 are portions that cover the side surface of the battery cell 11 (the surface that connects the upper surface 54A and the bottom surface to each other) when the battery cell 11 is held. The back surface portion 25 is provided so as to connect the side wall portion 23 and the side wall portion 24 in a state where the thickness direction thereof is along the first direction. The position of the upper end 25A of the back surface 25 coincides with the positions 23A and 24A of the upper ends of the side wall 23 and the side wall 24. When holding the battery cell 11, the back surface 25 covers a part of the upper surface 54A of the lid 54 in the battery cell 11.

The extending portion 26 is provided at the positions 23A and 24A of the upper ends of the side wall portion 23 and the side wall portion 24, respectively. The pair of extending portions 26 are arranged so as to face each other and extend along a third direction. Protrusions 27 are provided on the surfaces of the pair of extending portions 26 facing each other.

As shown in FIGS. 4 and 5, the protrusion 27 stands at the tip of the extending portion 26 from the positions 23A and 24A of the upper ends of the side wall portion 23 and the side wall portion 24, respectively, to stand the first cover 61 described later. It is formed at a position separated by a distance corresponding to the height of the installation portion 61D. As an example, the protrusion 27 is formed in a triangular columnar shape extending along the first direction at the tip end portion of the extending portion 26. The length of the protrusion 27 in the first direction is shorter than the length of the extending portion 26 in the first direction. The protrusions 27 include a pair of outer surfaces 27A at both ends in the first direction. In the present embodiment, the outer surface 27A is a first intersection surface that intersects (orthogonally) in the first direction. Therefore, the holder 21 includes a first intersection surface (outer surface 27A) that intersects in the first direction.

As shown in FIG. 5, the protrusion 27 projects from the extending portion 26 onto the first cover 61 along the second direction. Therefore, the protrusion 27 can be engaged with the upright portion 61D. When the protrusion 27 and the upright portion 61D are engaged, the contact surface 27B, which is the surface of the protrusion 27 on the first cover 61 side (upper surface 54A side), comes into contact with the end surface 61G of the upright portion 61D. Here, the end face 61G is an opposite surface extending along the upper surface 54A on the opposite side of the facing surface 61S facing the upper surface 54A in the first cover 61. Therefore, the protrusion 27 includes a contact surface 27B that contacts the opposite surface. As a result, the protrusion 27 restricts the movement of the first cover 61 so as to be separated from the upper surface 54A. The amount of protrusion along the second direction of the protrusion 27 is, for example, greater than or equal to the thickness of the upright portion 61D. The amount of protrusion of the protrusion 27 along the second direction may be less than the thickness of the standing portion 61D.

As shown in FIGS. 4 and 5, the projecting portion 29 is provided at the positions 23C and 24C of the lower end portions of the side wall portion 23 and the side wall portion 24 in the third direction, respectively. The protruding portion 29 is provided with an insertion hole 29A penetrating along the first direction. The bolt B described above is inserted into the insertion hole 29A.

The terminal accommodating portion 31 is provided at both ends of the upper end 25A of the back surface portion 25 in the second direction. The terminal accommodating portion 31 is provided so as to be connected to the side wall portion 23 and the side wall portion 24, respectively. The terminal accommodating portion 31 is U-shaped when viewed from the third direction, and opens in the direction opposite to the first direction. The terminal accommodating portion 31 is a portion that surrounds the electrode terminals 55 of the battery cell 11 when holding the battery cell 11.

Each of the projecting portions 33 is provided so as to be adjacent to the terminal accommodating portion 31 at the upper end 25A of the back surface portion 25. The projecting portion 33 is a square columnar extending along the first direction, and its length corresponds to, for example, the length of the bottom wall portion 22 in the first direction. The protrusion 33 is provided with an insertion hole 33A that penetrates along the first direction. The bolt B described above is inserted into the insertion hole 33A.

In the holder 21, the accommodating portion CL in which the battery cell 11 is accommodated is formed by the space surrounded by the bottom wall portion 22, the side wall portion 23, the side wall portion 24, the back surface portion 25, and the projecting portion 33 described above. A thermistor (temperature sensor) 91 is provided on the upper surface 54A in a state where the battery cell 11 is accommodated in the accommodating portion CL.

Here, the battery module 10 includes a plurality of thermistors 91. As shown in FIG. 2, for example, the thermistor 91 is a battery cell 11A which is the third battery cell 11 counting from the end plate 12A and a battery cell 11 which is the third battery cell 11 counting from the end plate 12B. It is provided in 11B and a battery cell 11C located in the center of the laminated body of the battery cells 11. Of the plurality of battery cells 11, the battery cell 11C is a temperature measuring cell provided with the thermistor 91. As shown in FIG. 1, a signal line (not shown) connected to the control device 93 is connected to the thermistor 91 via a connection terminal. The detection signal of the thermistor 91 is transmitted to the control device 93 via the signal line and the connection terminal.

As shown in FIGS. 1 and 2, the battery module 10 includes a first cover 61, a second cover 62, and a second cover 63. The first cover 61 is provided so as to face the upper surface 54A. The first cover 61 is arranged to face the upper surface 54A so as to cover at least two adjacent battery cells 11 including the battery cell 11C, which is the battery cell 11 provided with the thermistor 91. On the first cover 61, for example, a control device 93 including an electronic component that contributes to charging and discharging of the battery cell 11 and a battery ECU that controls the battery module 10 is mounted. The first cover 61 is, for example, a resin member.

As shown in FIGS. 5 and 6, the first cover 61 has a main body portion 61A, a pair of standing portions 61D, and a pair of extending portions 61E. The main body 61A is formed in a rectangular flat plate shape. The main body 61A has a facing surface 61S facing the upper surface 54A and an opposing surface 61T extending along the upper surface 54A on the opposite side of the facing surface 61S.

The upright portion 61D is provided at both ends of the main body portion 61A in the second direction. The erection portion 61D is erected on the opposite surface 61T so as to extend along the third direction. The pair of upright portions 61D face each other in the second direction. The upright portion 61D extends substantially throughout the main body portion 61A in the first direction.

The extension portion 61E is erected on the facing surface 61S so as to extend along the third direction. The pair of extension portions 61E are arranged so as to face each other with the release valve 57 in the second direction. The extension portion 61E extends substantially throughout the main body portion 61A in the first direction. The extension portion 61E is in contact with the upper surface 54A. An elastic member or the like may be provided at the lower end of the extension portion 61E. The extension portion 61E does not have to be in contact with the upper surface 54A.

The first cover 61 has a pressing portion 70 for pressing the thermistor 91 against the battery cell 11C. The pressing portion 70 includes a protrusion 71, a spring seat portion 72, and a spring SP. As an example, the protrusion 71 is formed in a columnar shape so as to protrude from the facing surface 61S. The protrusion 71 is integrally formed with the first cover 61. The protrusion 71 defines the position of the spring SP and suppresses the spring SP from coming off. The spring seat portion 72 is a portion that comes into contact with one end of the spring SP. The spring seat portion 72 is, for example, a part of the facing surface 61S. The spring seat portion 72 may be formed so as to protrude from the facing surface 61S, or may be formed by recessing the facing surface 61S.

One end of the spring SP is fitted to the protrusion 71 so as to surround the protrusion 71. The other end of the spring SP comes into contact with the upper surface of the thermistor 91. The spring SP presses the thermistor 91 against the upper surface 54A of the battery cell 11C by being compressed between the spring seat portion 72 and the thermistor 91.

As shown in FIG. 6, the first cover 61 has a positioning unit 80 that positions the holder 21 that holds the battery cell 11C in the first direction. The positioning portion 80 has a pair of engaging claws 81. The engaging claw 81 is, for example, a protrusion formed on the end surface 61G of the standing portion 61D. The engaging claws 81 have a right-angled triangular shape when viewed from the second direction, and their hypotenuse portions are formed so as not to face each other.

Each of the engaging claws 81 includes an inner surface 81A that intersects (orthogonally) in the first direction. The inner surface 81A here is one surface that sandwiches a right angle of a right triangle. Therefore, the inner surface 81A is a second intersection surface that intersects (orthogonally) in the first direction. The pair of inner surfaces 81A face each other in the first direction so as to be separated from each other by a length equal to or longer than the length of the protrusion 27 in the first direction. By interposing the protrusions 27 between the pair of inner surfaces 81A, the engaging claws 81 engage with the protrusions 27 from both sides in the first direction. The inner surface 81A faces the outer surface 27A of the protrusion 27 when the engaging claw 81 engages with the protrusion 27. The positioning portion 80 is abutted between the inner surface 81A and the outer surface 27A (that is, abutted between the first intersection surface and the second intersection surface) on both sides of the first direction (the first direction and the opposite direction of the first direction). In, the first cover 61 is positioned with respect to the holder 21.

The second cover 62 is arranged to face the upper surface 54A so as to be adjacent to the first cover 61 along the first direction. As shown in FIG. 2, the second cover 62 is fixed to the end plate 12B at one end 62F in the first direction. The second cover 63 is arranged so as to face the upper surface 54A so as to be adjacent to the first cover 61 on the side opposite to the second cover 62 along the first direction. The second cover 63 is fixed to the intermediate plate 15 at one end 63F in the first direction. The second covers 62 and 63 are, for example, resin members.

As shown in FIGS. 2 and 6, the first cover 61 and the second cover 62 overlap the overlapping portions 61B and 62B along the direction (third direction: Z-axis direction) intersecting the upper surface 54A. Each has. The overlapping portion 62B is formed at an end portion of the second cover 62 opposite to the end portion 62F fixed to the end plate 12B. The first cover 61 and the second cover 63 each have an overlapping portion 61C and an overlapping portion 63C that overlap each other along a direction intersecting the upper surface 54A. The overlapping portion 63C is formed at an end portion of the second cover 63 opposite to the end portion 63F fixed to the intermediate plate 15. The overlapping portions 61B and 61C are formed at both ends of the first cover 61 in the first direction, respectively. The overlapping portion 61B overlaps the overlapping portion 62B, and the overlapping portion 61C overlaps the overlapping portion 63C. That is, the first cover 61 is relatively movable in the first direction with respect to the second covers 62 and 63 in a state of overlapping each other.

The second covers 62 and 63 are the first, except that they include the above-mentioned configurations of the end portions 62F and 63F and the configurations of the overlapping portions 62B and 63C, and do not include the positioning portion 80 (described later). It has the same configuration as the cover 61. Therefore, the description of the second covers 62 and 63 that overlaps with the configuration of the first cover 61 will be omitted.

Next, the operation of the battery module 10 of the present embodiment will be described. The battery cell 11 may expand due to repeated charging and discharging or deterioration. As shown in FIGS. 1 and 2, in the battery module 10, a plurality of battery cells 11 are constrained by the end plates 12A and 12B. In the battery module 10, the elastic member 17 is arranged between the end plates 12A and 12B. Therefore, as shown in FIGS. 7 and 8, when the battery cell 11 expands, the battery cell 11 moves toward the elastic member 17 along the first direction. The load due to the expansion of the battery cell 11 is absorbed by the elastic member 17 being crushed.

FIG. 7 is a cross-sectional view showing a relative position change between the pressing portion and the thermistor in the battery module according to the comparative example. FIG. 8 is a cross-sectional view showing a relative position change between the pressing portion 70 and the thermistor 91 in the battery module 10 shown in FIG. In the battery module shown in FIG. 7, the engaging claw 81 is not formed on the first cover 61, and the first cover 61 is positioned in the first direction with respect to the holder 21 that holds the battery cell 11C. Absent.

As shown in FIG. 7, when the battery cell 11 expands, the holder 21 holding the battery cell 11C moves in a direction away from the end plate 12B (to the right in FIG. 7) by a distance D1. Along with this, the first cover 61 may move, for example, along the first direction by a distance D2. In the example of FIG. 7, since the positioning is not performed, the distance D1 and the distance D2 generally do not match. Therefore, in this case, due to the expansion of the battery cell 11, the pressing portion 70 may move relative to the thermistor 91 in the first direction, and the position where the pressing portion 70 presses the thermistor 91 may shift.

On the other hand, as shown in FIG. 8, when the positioning unit 80 positions the holder 21 holding the battery cell 11C in the first direction (that is, the engaging claw 81 is formed on the first cover 61). When the battery cell 11 expands, the holder 21 moves in the direction away from the end plate 12B (to the right in FIG. 8) by a distance D1. Along with this, the first cover 61 moves along the first direction by a distance D3. In this case, since the positioning is performed, the first cover 61 is integrally moved with the holder 21 in the first direction. Therefore, the distance D1 and the distance D3 substantially match. Therefore, in this case, the expansion of the battery cell 11 prevents the pressing portion 70 from moving relative to the thermistor 91 in the first direction.

As described above, in the battery module 10, the first cover 61 is positioned so that the pressing portion 70 for pressing the thermistor 91 against the battery cell 11C and the holder 21 holding the battery cell 11C are positioned in the first direction. It has a part 80 and. As a result, when the battery cell 11 expands, the holder 21 holding the battery cell 11C, which is a temperature measuring cell, and the first cover 61 move integrally in the first direction. Therefore, the relative movement between the pressing portion 70 of the first cover 61 and the thermistor 91 on the battery cell 11C side is suppressed. As a result, the state in which the thermistor 91 is pressed against the battery cell 11C by the pressing portion 70 of the first cover 61 is maintained. That is, according to the battery module 10, the thermistor 91 can be more reliably pressed against the battery cell 11C provided with the thermistor 91.

In the battery module 10, the holder 21 that holds the battery cell 11C includes a first intersection surface that intersects (orthogonally) in the first direction. The first cover 61 includes a second intersection surface that intersects (orthogonally) in the first direction. The positioning unit 80 is positioned by abutting the first intersection surface and the second intersection surface. As a result, the first intersection surface of the holder 21 and the second intersection surface of the first cover 61 abut each other in the first direction, so that the first direction of the first cover 61 with respect to the holder 21 holding the battery cell 11C Positioning is possible.

In the battery module 10, the holder 21 that holds the battery cell 11C has a protrusion 27 that projects onto the first cover 61. The first intersecting surface is the outer surface 27A of the protrusion 27. The positioning portion 80 has engaging claws 81 that engage with the protrusions 27 from both sides of the protrusions 27 in the first direction. The second intersecting surface is the inner surface 81A of the engaging claw 81 facing the outer surface 27A. As a result, the outer surface 27A of the holder 21 holding the battery cell 11C and the inner surface 81A of the first cover 61 have a simple structure in which they abut each other on both sides of the first direction (opposite directions of the first direction and the first direction). Positioning is possible.

In the battery module 10, the first cover 61 has an facing surface 61S facing the upper surface 54A and an end surface 61G which is an opposite surface extending along the upper surface 54A on the opposite side of the facing surface 61S. The protrusion 27 includes a contact surface 27B that contacts the end surface 61G. As a result, since the protrusion 27 comes into contact with the end face 61G on the contact surface 27B, the movement of the first cover 61 so as to be separated from the upper surface 54A can be restricted.

The battery module 10 includes second covers 62 and 63 arranged to face the upper surface 54A so as to be adjacent to the first cover 61 along the first direction. As a result, by arranging the second covers 62 and 63 according to the number of battery cells 11 in the battery module 10, the first cover 61 and the second covers 62 and 63 reliably cover and protect the battery cells 11. Can be done.

In the battery module 10, the first cover 61 has overlapping portions 61B, 61C that overlap the second covers 62, 63 along the direction intersecting the upper surface 54A. As a result, even if the holder 21 and the first cover 61 move along the first direction due to the expansion of the battery cell 11, the overlapping portions 61B, 62B, of the first cover 61 and the second covers 62, 63, The state in which the battery cell 11 is covered by the first cover 61 and the second covers 62 and 63 is maintained within the range in which the 61C and 63C overlap.

The battery module 10 includes an elastic member 17 constrained together with the battery cell 11 along the first direction. As a result, even if the battery cell 11 expands and the battery cell 11 moves along the first direction, the load due to the expansion of the battery cell 11 can be absorbed by, for example, the elastic member 17 being crushed. Further, at this time, since the movement of the battery cell 11 along the first direction becomes relatively large, the effect of positioning the first cover 61 by the positioning portion 80 becomes remarkable.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. Various changes can be made without departing from the spirit of the invention.

The battery module 10 of the above embodiment includes, but is not limited to, three covers (first cover 61 and second covers 62, 63) that are adjacent to each other in the stacking direction (first direction) of the battery cells 11. .. The battery module 10 may include at least one first cover 61.

In the above embodiment, as the positioning unit 80, the engaging claw 81 that positions the first cover 61 in the first direction with respect to the holder 21 that holds the battery cell 11C is illustrated. However, the positioning portion 80 holds the other battery cell 11B provided with the thermistor 91, for example, by forming an engaging claw on the second cover 62 and releasing the fixing of the second cover 62 to the end plate 12B. The second cover 62 may be positioned with respect to the holder 21 in the first direction. Further, the positioning unit 80 holds the other battery cell 11A provided with the thermistor 91, for example, by forming an engaging claw on the second cover 63 and releasing the fixing of the second cover 63 to the intermediate plate 15. The second cover 63 may be positioned in the first direction with respect to the holder 21.

In the above embodiment, the engaging claw 81 that engages with the protrusion 27 is illustrated as the positioning portion 80, but the positioning portion is not limited to this. For example, it may be a positioning portion in which a hole is formed in either one of the holder 21 and the first cover 61, and a protrusion formed in the other of the holder 21 and the first cover 61 is inserted into the hole for positioning. .. Further, for example, it may be a positioning portion in which holes are formed at corresponding positions of the holder 21 and the first cover 61, and positioning is performed by inserting a pin through each of the holes. That is, the positioning unit 80 can be in any form capable of positioning by abutting the surfaces intersecting in the first direction. Further, the surfaces intersecting in the first direction may be a flat surface or a curved surface such as the surface of a columnar protrusion.

In the above embodiment, one holder 21 holds one battery cell 11C provided with the thermistor 91, and the positioning unit 80 positions the first cover 61 in the first direction with respect to the holder 21. One holder may hold a plurality of battery cells 11 including, for example, a battery cell 11 provided with a thermistor 91. In this case, the positioning unit 80 may position the first cover 61 in the first direction with respect to the one holder.

In the above embodiment, the elastic member 17 is arranged between one end plate 12A and the intermediate plate 15, but the elastic member 17 may be restrained together with the battery cell 11 along the first direction. It may be arranged in another position.

In the above embodiment, the pressing portion 70 presses the thermistor 91 against the battery cell 11C by the spring SP, but the thermistor 91 may be pressed against the battery cell 11C by another elastic member such as rubber. Further, in the above embodiment, one thermistor 91 is provided in each of the three battery cells 11A, 11B, and 11C, and the battery module 10 includes the three thermistors 91, but the number of thermistors 91 is as follows. It may be any other number. At this time, for example, the thermistor 91 may be provided in the battery cell 11 where the temperature tends to be high.

10 ... Battery module, 11 ... Battery cell, 11C ... Battery cell (temperature measuring cell), 12A, 12B ... End plate (restraint part), 17 ... Elastic member (elastic member), 21 ... Holder, 27 ... Protrusion, 27A ... Outer surface (first crossing surface), 27B ... contact surface, 54A ... upper surface (main surface), 55 ... electrode terminal, 61 ... first cover, 61S ... facing surface, 61T ... opposite surface, 62, 63 ... second cover, 61B, 62B, 61C, 63C ... Overlapping part, 70 ... Pressing part, 80 ... Positioning part, 81 ... Engaging claw, 81A ... Inner surface (second crossing surface), 91 ... Thermistor (temperature sensor).

Claims (6)

A plurality of battery cells having a main surface and electrode terminals provided on the main surface and stacked on each other along a first direction,
A plurality of holders for individually holding the battery cells,
A restraining portion that restrains the plurality of battery cells along the first direction, and
A temperature sensor provided on the main surface of at least one battery cell and
A first cover is provided so as to cover at least two adjacent battery cells including a temperature measuring cell, which is the battery cell provided with the temperature sensor, so as to face the main surface.
The first cover has a pressing portion for pressing the temperature sensor against the temperature measuring cell, and a positioning portion for positioning the holder holding the temperature measuring cell in the first direction. And
The holder holding the temperature measuring cell includes a first intersecting surface that intersects in the first direction.
The first cover includes a second crossing surface that intersects in the first direction.
The positioning portion is a battery module that performs the positioning by abutting the first intersection surface and the second intersection surface . The holder that holds the temperature measuring cell has a protrusion that projects onto the first cover.
The first intersecting surface is the outer surface of the protrusion.
The positioning portion has a pair of engaging claws that engage the protrusion from both sides of the protrusion in the first direction.
The second intersecting surface is an inner surface of the pair of engaging claws facing the outer surface.
The battery module according to claim 1 . The holder that holds the temperature measuring cell has a protrusion that projects onto the first cover.
The first cover has a facing surface facing the main surface and an opposite surface extending along the main surface on the opposite side of the facing surface.
The protrusion includes a contact surface that contacts the opposite surface.
The battery module according to claim 1 . A second cover arranged so as to be adjacent to the first cover along the first direction and facing the main surface is further provided.
The battery module according to claim 1 . Further, a second cover arranged so as to be adjacent to the first cover along the first direction and facing the main surface is provided.
The first cover has an overlapping portion that overlaps with the second cover along a direction intersecting the main surface.
The battery module according to claim 1 . An elastic member constrained with the battery cell along the first direction is further provided.
The battery module according to claim 1 .

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