JP7318515B2 - battery stack - Google Patents

Description

The present invention relates to battery stacks.

Conventionally, a battery stack (battery module) is made by stacking a plurality of battery cells in the lateral direction of a substantially rectangular battery cell, and connecting a pair of end plates arranged at both ends with restraint bands. Each battery cell is fixed with a load applied in the stacking direction (see, for example, Patent Document 1).

JP-A-2008-53019

By the way, in the case of the battery stack of Patent Document 1, the battery cells are stacked with a resin battery holder (holding frame) interposed between the battery cells. accuracy) has room for improvement.

SUMMARY OF THE INVENTION An object of the present invention is to provide a battery stack in which positioning accuracy of battery cells is improved.

The battery stack according to claim 1 includes a plurality of battery cells each having a substantially rectangular shape, and attached to both end surfaces of the battery cells in the stacking direction. a pair of first restraining members each formed with a pair of first inclined surfaces that form a predetermined angle with the stacking direction and are inclined toward the end surface in the stacking direction toward the end in the orthogonal direction; and the battery cell. The orthogonal ends of the set of first restraining members are inserted and a pair of second slanted surfaces corresponding to the first slanted surfaces of the first set of restraining members are formed. A set of second restraining members each having a recess and a load in the orthogonal direction that causes the set of second restraining members to approach each other can be applied to the second restraining members. and load applying means including a biasing member that is elastically deformable in the orthogonal direction .

In this battery stack, first restraining members are attached to both end surfaces of each battery cell in the stacking direction. At both end portions of each first restraining member in the orthogonal direction orthogonal to the stacking direction, first inclined surfaces are formed that are inclined at a predetermined angle with respect to the stacking direction toward the end surfaces in the stacking direction of the battery cells toward the end portions in the orthogonal direction. ing.

Here, the “stacking direction” is the direction in which a plurality of battery cells are arranged in the battery stack. Also, the "predetermined angle" is greater than 0 degrees and less than 90 degrees.

That is, in a state in which a set of first restraining members are attached to both end surfaces of the battery cell in the stacking direction (hereinafter referred to as a "battery cell unit"), both ends in the orthogonal direction are tapered toward both ends in the orthogonal direction. The first inclined surface is formed so as to be

In this manner, both ends of the battery cell unit in the orthogonal direction are inserted into the recesses of the pair of second restraining members.

Since a pair of second slanted surfaces corresponding to the pair of first slanted surfaces of the battery cell unit (first restraining member) are formed in the recess, the end of the battery cell unit in the orthogonal direction is placed in the recess. By being inserted, the first inclined surface of the battery cell unit (first restraining member) is brought into contact with the second inclined surface of the recess. Thereby, the battery cell unit is accurately positioned on the second restraining member.

In this way, in the battery cell unit in which the first restraining member attached to the end surface of the battery cell in the stacking direction and the battery cell are integrated, the vertical end portion perpendicular to the stacking direction is aligned with the concave portion of the second restraining member. Positioned by mating.

Further, in this battery stack, the load applying means applies a load to the second restraining members in a direction in which the pair of second restraining members approach each other in the orthogonal direction. Therefore, a restraining load acts on each first restraining member from the second restraining member, and further, a restraining load in the stacking direction is applied to the battery cell from the pair of first restraining members attached to both end surfaces of the battery cell in the stacking direction. works.

FIG. 3 is a cross-sectional view taken along line AA of FIG. 2; 4 is a cross-sectional view taken along the line BB of FIG. 3; FIG. FIG. 2 is a top plan view of the battery stack according to the first embodiment, as viewed in the up-down direction; FIG. 4 is a schematic exploded explanatory view for explaining shapes of first to third restraining members that constitute the battery stack according to the first embodiment; FIG. 2 is a cross-sectional view of a battery stack according to a second embodiment corresponding to FIG. 1; 1. It is sectional drawing of the battery stack based on 3rd Embodiment corresponding to FIG. It is a principal part enlarged view which shows the variation of a pressurization means.

[First embodiment]
A battery stack according to a first embodiment will be described with reference to FIGS. 1 to 4. FIG. In each figure below, the direction in which the battery cells are stacked is indicated by an arrow X direction, the horizontal direction is indicated by an arrow Y direction, and the vertical direction is indicated by an arrow Z direction. The same applies to the following embodiments. Also, in each cross-sectional view, hatching of the battery cells 12 is omitted in order to avoid complication of the drawing. Furthermore, in FIG. 4, the illustration of the battery cell unit 44 is partially omitted in order to explain the shapes of the concave portions 52 and 62 of the second restraining member 18 and the third restraining member 20. As shown in FIG. Moreover, in each figure, only one portion of a plurality of identical constituent elements may be denoted by a reference numeral, and the others may be omitted.

(composition)
An overall configuration of the battery stack 10 will be described.

As shown in FIGS. 1 and 3, the battery stack 10 includes a plurality of battery cells 12, a pair of end plates 14A and 14B, a plurality of first restraining members 16A and 16B, and a second restraining member 18. , a third restraining member 20, a pressing means 22 for applying a restraining load to each battery cell 12, a restraining member 24, and a case 26 in which these are installed.

In addition, the first restraining members 16A and 16B are the "first restraining members", the second restraining members 18 and the third restraining members 20 are the "second restraining members", and the pressing means 22 is the "restraining load application respectively correspond to "means"

As shown in FIG. 4, each battery cell 12 has a substantially rectangular shape, and first restraining members 16A and 16B are attached to end faces 30A and 30B on both sides in the stacking direction (direction of arrow X), respectively. It is something that can be done.

As shown in FIG. 4, the first restraining member 16A has a substantially trapezoidal shape when viewed in the vertical direction (the arrow Z direction (see FIG. 2)) perpendicular to the stacking direction (the arrow X direction). That is, the first restraining member 16A extends in the stacking direction from a mounting surface 32A having the same shape as the end surface 30A, and from both ends of the mounting surface 32A in the arrow Y direction (hereinafter sometimes referred to as the "left and right direction"). a left end face 34A and a right end face 36A, a stacking direction end face 38A formed parallel to the mounting face 32A facing the mounting face 32A, and an inclination formed from the left end of the stacking direction end face 38A toward the left end face 34A. It has a surface 40A and an inclined surface 42A formed from the right end of the end surface in the stacking direction toward the right end surface 36A.

As shown in FIG. 4, the inclined surface 40A is inclined at an angle of θ1 (0°<θ1<90°) with respect to the stacking direction (arrow X direction) and formed from the stacking direction end surface 38A toward the left end surface 34A. It is Similarly, as shown in FIG. 4, the inclined surface 42A is inclined at an angle of θ1 (0°<θ1<90°) to the side opposite to the inclined surface 40A with respect to the stacking direction (arrow X direction). It is formed from the end face 38A toward the right end face 36A.

As shown in FIG. 4, the first restraining member 16B is formed line-symmetrically with the first restraining member 16A and the battery cell 12 interposed therebetween. is indicated by adding B to the reference number of , and detailed description thereof will be omitted.

A battery cell 12 to which the first restraining members 16A and 16B are attached on both sides in the stacking direction may be hereinafter referred to as a "battery cell unit 44".

By attaching the first restraining members 16A and 16B to both sides of the battery cell 12 in the stacking direction in this manner, the inclined surfaces 40A and 40B of the first restraining members 16A and 16B approach each other toward the left end. , and the inclined surfaces 42A, 42B are configured (tapered) to approach each other toward the right end.

Note that the inclined surfaces 40A, 40B, 42A, and 42B correspond to the "first inclined surface".

The second restraining member 18 positions the battery cell unit 44 (battery cell 12) together with the third restraining member 20. As shown in FIG.

As shown in FIGS. 1 and 3, the second restraining members 18 are arranged on one surface 51 of a substantially rectangular shape (hereinafter referred to as "restraining surface") at equal intervals along the stacking direction in the vertical direction (the direction of the arrow Z). ) are formed, and recesses 52 are formed between the adjacent protrusions 50 . A flat contact surface 96 is formed on the opposite side of the restraining surface 51 of the second restraining member 18 .

As shown in FIG. 4, the recess 52 has a bottom surface 54 and a pair of inclined surfaces 56A and 56B extending from both ends of the bottom surface 54 in the stacking direction toward the opening. The inclination angle θ2 of the inclined surfaces 56A and 56B with respect to the bottom surface 54 (laminating direction) is the same as the inclination angle θ1 between the left end surfaces 34A and 34B (laminating direction) of the first restraining members 16A and 16B and the inclined surfaces 40A and 40B. is set to Note that the inclined surfaces 56A and 56B correspond to the "second inclined surface".

In addition, the stacking direction width of the bottom surface 54 of the recess 52 is narrower than the stacking direction width of the left end surface of the battery cell unit 44 (the left end surface of the battery cell 12 and the left end surfaces 34A and 34B of the first restraining members 16A and 16B). . In addition, the stacking direction width of the opening of the concave portion 52 is wider than the stacking direction width of the left end surface of the battery cell unit 44 .

Therefore, when the left end of the battery cell unit 44 is inserted into the recess 52 of the second restraining member 18, the inclined surfaces 40A and 40B of the battery cell unit 44 (first restraining members 16A and 16B) are aligned with the inclined surfaces of the recess 52. The battery cell unit 44 is positioned by abutting against 56A and 56B.

In addition, as shown in FIG. 3, the protrusions 50 (hereinafter referred to as "protrusions 50A" and "protrusions 50B" respectively) formed at both ends of the second restraining member 18 in the stacking direction have Also, like the other convex portions 50, inclined surfaces 56B and 56A are formed, and are in contact with inclined surfaces 40B and 40A of first restraining members 16B and 16A, which will be described later, attached to the end plates 14A and 14B. It is a configuration that

As shown in FIG. 3, the third restraining member 20 is provided on one side of a substantially rectangular shape (hereinafter referred to as "restraining surface") 61 at equal intervals along the stacking direction, similarly to the second restraining member 18. As shown in FIG. A plurality of protrusions 60 each having a trapezoidal shape in the vertical direction extending in the vertical direction (in the direction of arrow Z) are formed on the upper surface of the housing, and recesses 62 are formed between the adjacent protrusions 60 .

As shown in FIG. 4, the recess 62 has a bottom surface 64 and a pair of inclined surfaces 66A and 66B extending from both ends of the bottom surface 64 in the stacking direction toward the opening. The inclination angle θ3 of the inclined surfaces 66A and 66B with respect to the bottom surface 64 (laminating direction) is the same as the inclination angle θ1 between the right end surfaces 36A and 36B (laminating direction) of the first restraining members 16A and 16B and the inclined surfaces 42A and 42B. is set to Note that the inclined surfaces 66A and 66B correspond to the "second inclined surface".

In addition, the stacking direction width of the bottom surface 64 of the recess 62 is narrower than the stacking direction width of the right end surface of the battery cell unit 44 (the end surface of the battery cell 12 and the right end surfaces 36A and 36B of the first restraining members 16A and 16B). Moreover, the stacking direction width of the opening of the concave portion 62 is wider than the stacking direction width of the right end face of the battery cell unit 44 .

Therefore, by inserting the right end of the battery cell unit 44 into the concave portion 62 of the third restraining member 20, the inclined surfaces 42A and 42B of the battery cell unit 44 are brought into contact with the inclined surfaces 66A and 66B of the concave portion 62. Battery cell unit 44 is positioned.

In addition, as shown in FIG. 3, outside the protrusions 60 (hereinafter referred to as "protrusions 60A" and "protrusions 60B") formed at both ends of the third restraining member 20 in the stacking direction, Similarly, sloped surfaces 66B, 66A are formed to contact sloped surfaces 42B, 42A of first restraining members 16B, 16A, which are attached to the end plates 14A, 14B and will be described later.

In addition, the inclined surfaces 40A, 40B, 42A and 42B correspond to the "first inclined surface", and the inclined surfaces 56A, 56B, 66A and 66B correspond to the "second inclined surface".

In addition, three recesses 68 are provided at equal intervals in the stacking direction on the other surface (hereinafter referred to as "pressure surface") 63 opposite to the restraining surface 61 of the third restraining member 20 .

The case 26 in which the battery cell unit 44, the second restraining member 18 and the third restraining member 20 are housed is, as shown in FIGS. It has a rectangular body shape. That is, the case 26 includes a bottom wall 70 , a front wall 72 and a rear wall 74 extending upward from both ends of the bottom wall 70 in the stacking direction, and a left wall extending upward from both ends of the bottom wall 70 in the left-right direction. It has a wall 76 and a right wall 78 .

As shown in FIG. 2, the bottom wall 70 includes a unit installation portion 80 in which the battery cell unit 44, the second restraining member 18, and the third restraining member 20 are arranged, and both ends of the unit installation portion 80 in the stacking direction. , end plate installation portions 82A and 82B for fixing end plates are provided below the unit installation portion 80 (in the direction of the arrow Z2).

A pair of linear guides 110 for guiding the third restraining member 20 are provided on the unit installation portion 80 below the third restraining member 20 so as to extend in the left-right direction. The linear guide 110 allows the third restraining member 20 to move accurately in the lateral direction.

As shown in FIG. 2, the end plates 14A and 14B have mounting portions 90A and 90B and end plate main bodies 92A and 92B, respectively, and are L-shaped when viewed in the left-right direction (as viewed in the direction of the arrow Y). . Mounting portions 90A and 90B of the end plates 14A and 14B are fastened to the end plate mounting portions 82A and 82B of the bottom wall 70 of the case 26, respectively. As a result, the end plates 14A, 14B are fixed to the bottom wall 70, and the end plate bodies 92A, 92B stand vertically (in the direction of arrow Z).

As shown in FIGS. 2 and 3, battery cells 12 (hereinafter sometimes referred to as battery cells 12A and 12B, respectively) are provided on the end faces of the end plate bodies 92A and 92B on the inner side in the stacking direction (on the side of the battery cell unit 44). ) is installed. First restraining members 16B and 16A are attached to end faces 30B and 30A of the battery cells 12A and 12B on the inside in the stacking direction (on the battery cell unit 44 side), respectively. The "first restraining members 16B, 16A" may be referred to as "first restraining members 16B, 16A attached to the end plates 14A, 14B".

Further, as shown in FIGS. 2 and 3, mounting recesses 84A for holding down members, which will be described later, are provided in the center of the left-right direction of the upper ends of the front wall 72 and the rear wall 74 of the case 26 (ends on the arrow Z1 direction side). 84B are provided facing each other.

As shown in FIGS. 2 and 3, the holding member 24 is a substantially plate-shaped member extending in the stacking direction, and has a holding portion 86 (shown in FIG. 2) are formed. Therefore, both ends of the holding member 24 in the stacking direction are fastened to the mounting recesses 84A and 84B, and are bridged between the front wall 72 and the rear wall 74, so that the holding portion 86 of the holding member 24 is attached to the bottom wall. It holds down the upper portion of the battery cell unit 44 arranged on the unit installation portion 80 of 70 (the end portion in the direction of the arrow Z1) to suppress displacement in the vertical direction. However, as will be described later, lateral displacement of the battery cell unit 44 is allowed.

Further, as shown in FIGS. 1 and 3, the left wall 76 of the case 26 is formed with an abutment portion 94, and the abutment portion 94 abuts the abutment surface 96 of the second restraining member 18. By fixing them in the folded state, the second restraining member 18 is fixed to the case 26 in a state in which the protrusions 50 and the recesses 52 are continuously arranged along the stacking direction.

At this time, as shown in FIG. 1, the inclined surfaces 56B, 56A of the protrusions 50A, 50B at both ends in the stacking direction of the second restraining member 18 are attached to the end plates 14A, 14B, the first restraining member 16B, Positioning of the second restraining member 18 in the stacking direction within the case 26 is achieved by contacting the inclined surfaces 40B, 40A of 16A.

Further, the right wall 78 of the case 26 is provided with three pressing means 22 as shown in FIG. Three threaded holes 100 are formed in the right wall 78 at equal intervals in the stacking direction, and a pressure adjusting member 102 constituting the pressurizing means 22 is screwed into each of the threaded holes 100 . A flange portion 104 is formed at one axial end portion of the pressure regulating member 102 , and the flange portion 104 is fastened (fixed) to the right wall 78 of the case 26 . A concave portion 106 is formed on the other axial end side of the pressure regulating member 102 . A coil spring 108 is arranged between the recess 106 and a recess 68 formed in the pressing surface 63 of the third restraining member 20 .

Therefore, the elastic force of the coil spring 108 arranged between the pressure regulating member 102 fixed to the right wall 78 of the case 26 and the third restraining member 20 causes the third restraining member 20 to move leftward (arrow Y1 direction). ).

Next, a method for assembling the battery stack 10 will be described.

First, the battery cells 12A, 12B are attached to the end faces of the end plate bodies 92A, 92B of the end plates 14A, 14B on the inside in the stacking direction (on the side opposite to the attachment portions 90A, 90B). Subsequently, the first restraining member 16B is attached to the stacking direction end surface 30B of the battery cell 12A, and the first restraining member 16A is attached to the stacking direction end surface 30A of the battery cell 12B.

Next, the mounting portions 90A and 90B of the end plates 14A and 14B to which the battery cells 12A and 12B and the first restraining members 16B and 16A are mounted are attached to the end plate mounting portions 82A and 82B of the bottom wall 70 of the case 26. By fastening, the end plates 14A and 14B are fixed at predetermined positions on the bottom wall 70. As shown in FIG.

Next, the abutting surface 96 of the second restraining member 18 abuts against the abutting portion 94 formed on the left wall 76 of the case 26 . At this time, the inclined surface 56B of the protrusion 50A formed at one end in the stacking direction of the second restraining member 18 abuts against the inclined surface 40B of the first restraining member 16B attached to the end plate 14A (FIG. 3). reference). Similarly, the inclined surface 56A of the protrusion 50B formed at the other end in the stacking direction of the second restraining member 18 is aligned with the inclined surface 40A of the first restraining member 16A attached to the end plate main body 92B of the end plate 14B. be hit. In this manner, the second restraining member 18 is positioned in the stacking direction and the left-right direction within the case 26 and fixed to the unit installation portion 80 .

Subsequently, the first restraining members 16A and 16B are attached to the end surfaces 30A and 30B of the battery cells 12 in the stacking direction, respectively. That is, the battery cell unit 44 is formed by integrating the battery cell 12 and the first restraining members 16A and 16B.

Furthermore, on the unit installation portion 80 of the case 26 , the left end of each battery cell unit 44 is inserted into each recess 52 of the second restraining member 18 fixed to the case 26 . As a result, the inclined surfaces 40A, 40B of the battery cell unit 44 (the first restraining members 16A, 16B) are brought into contact with the inclined surfaces 56A, 56B of the recess 52 .

Next, the third battery cell unit 44 is placed on the linear guide 110 provided in the unit installation portion 80 of the bottom wall 70 of the case 26 so that the right end of each battery cell unit 44 is inserted into the recess 62 of the third restraining member 20 . A restraining member 20 is installed. At this time, the inclined surfaces 66B, 66A of the protrusions 60A, 60B at both ends in the stacking direction of the third restraining member 20 are attached to the end plates 14A, 14B, and the inclined surfaces 42B of the first restraining members 16B, 16A are attached to the end plates 14A, 14B. , 42A are positioned in the case 26 in the stacking direction and the left-right direction.

Subsequently, the pressure adjusting member 102 is screwed into the screw hole 100 of the right wall 78 of the case 26, and the coil spring 108 is arranged between the recess 106 of the pressure adjusting member 102 and the recess 68 of the third restraining member 20. do. In this state, by fastening the flange portion 104 of the pressure regulating member 102 to the right wall 78, the pressure regulating member 102 is fixed to the case 26 (right wall 78), and the pressure regulating member 102 and the third restraining member are connected to each other. 20, the third restraint member 20 is biased leftward (in the direction of arrow Y1) by the elastic force of the coil spring 108 disposed between the third restraint member 20 and the third restraint member 20. As shown in FIG.

As a result, the inclined surfaces 40A, 40B at the left end of each battery cell unit 44 come into contact with the inclined surfaces 56A, 56B of the recess 52, and the inclined surfaces 42A, 42B at the right end of the battery cell unit 44 contact the recess 62. It abuts against the inclined surfaces 66A and 66B. That is, the battery cell unit 44 is positioned within the case 26 (on the unit installation portion 80 thereof). As shown in FIG. 1, at this time, gaps 306 are formed between the battery cell units 44 adjacent in the stacking direction. Further, gaps 308 and 310 are also formed between the first restraining members 16B and 16A attached to the end plates 14A and 14B and the adjacent battery cell units 44, respectively. (The battery cell units 44 are separated from each other in the stacking direction).

Finally, as shown in FIGS. 2 and 3, the holding member 24 is bridged between mounting recesses 84A and 84B formed in the upper ends of the front wall 72 and the rear wall 74 of the case 26, respectively. Both ends are fastened to the mounting recesses 84A and 84B. As a result, the holding portion 86 of the holding member 24 is brought into contact with the upper end portions of the battery cell unit 44 and the battery cells 12A and 12B arranged in the unit installation portion 80 of the case 26 . Here, the “contacted state” refers to a state in which the battery cell unit 44 is allowed to be displaced due to expansion and contraction, and is prevented from being displaced by vertical movement.

(action)
The operation of the battery stack 10 configured in this way will be described.

The second restraining member 18 of the battery stack 10 has a contact surface 96 in contact with the abutting portion 94 of the case 26 and serves as a first restraining member 18 attached to the end plates 14A and 14B fixed to the case 26 . By contacting the inclined surfaces 40B and 40A of the members 16B and 16A with the inclined surfaces 56B and 56A formed on the convex portions 50 at both ends in the stacking direction of the second restraining member 18, the members 16B and 16A are held at predetermined positions in the case 26. Positioned. That is, each recessed part 52 opened to the right of the second restraining member 18 is arranged along the stacking direction.

Similarly, the third restraining member 20 of the battery stack 10 is movable in the left-right direction by a linear guide 110 fixed to the case 26, and the first restraining member is attached to the end plates 14A and 14B. The inclined surfaces 66B, 66A formed on the protrusions 60 at both ends in the stacking direction of the third restraining member 20, which is biased leftward by the pressing means 22, abut against the inclined surfaces 42B, 42A of 16B, 16A. By doing so, it is positioned at a predetermined position within the case 26 . That is, each recessed part 62 opened leftward of the 3rd restraint member 20 is arranged along the stacking direction.

In this way, the left end and right end of the battery cell unit 44 are inserted into the recess 52 of the second restraining member 18 and the recess 62 of the third restraining member 20 positioned at predetermined positions in the case 26, respectively. As a result, the battery cell unit 44 (battery cell 12) is positioned within the case 26 with high accuracy in the stacking direction and the left-right direction.

In addition, each battery cell unit 44 is arranged on the unit installation portion 80 of the case 26, and the upper portion thereof is held down by the holding portion 86 of the holding member 24 fixed to the case 26, so that positioning accuracy in the vertical direction is ensured. be done.

In this way, in the battery stack 10, each battery cell unit 44 is positioned with high accuracy in all of the stacking direction, the horizontal direction, and the vertical direction within the case 26. , the battery cell units 44 are prevented from being displaced and the positioning accuracy is prevented from deteriorating.

In particular, as shown in FIG. 4, the inclination angle θ2 between the inclined surfaces 56A and 56B of the recess 52 of the second restraining member 18 and the stacking direction and the inclination of the battery cell unit 44 (first restraining members 16A and 16B) The surfaces 40A and 40B have the same inclination angle θ1 with respect to the stacking direction. Similarly, the inclined surfaces 66A and 66B of the recessed portion 62 of the third restraint member 20 and the inclined surfaces 42A and 42B of the battery cell unit 44 (the first restraint members 16A and 16B) are laminated. The inclination angle θ1 formed with the direction is formed to be the same. Therefore, by inserting the left end portion and the right end portion of the battery cell unit 44 into the recesses 52 and 62, respectively, the inclined surfaces 40A, 40B, 42A, and 42B of the battery cell unit 44 and the second restraining member 18 and the third restraining member 18 are aligned. The inclined surfaces 56A, 56B, 66A, and 66B of the member 20 are brought into contact with each other, and the battery cell unit 44 (battery cell 12) is accurately positioned.

Further, in this abutting state, the third restraining member 20 is urged leftward (arrow Y1 direction) by the pressurizing means 22, so that the second restraining member 18 and the third restraining member 20 move from the second restraining member 18 and the third restraining member 20 to the left. A load perpendicular to the inclined surfaces 40A, 40B, 42A and 42B acts on the 1 restraining members 16A and 16B.

Further, a load ( restraint load) acts.

As described above, in the battery stack 10, the biasing force of the pressurizing means 22 (coil spring 108) pushes the battery from the second restraining member 18 and the third restraining member 20 through the first restraining members 16A and 16B. A stacking direction (constrained) load acts on the cell 12 . At this time, the inclination angle θ1 of the inclined surfaces 40A, 40B, 42A, and 42B of the battery cell unit 44 (first restraining members 16A, 16B) with respect to the stacking direction and the inclination angle θ1 of the inclined surfaces 56A, 56B of the second restraining member 18 are Since the inclination angle θ2 with respect to the lamination direction and the inclination angle θ3 with respect to the lamination direction of the inclined surfaces 66A and 66B of the third restraining member 20 are set to be the same, the inclined surfaces are in surface contact with each other, and the load is reliably applied, and the load is applied in the horizontal direction. is converted into a direction inclined by a predetermined angle (≠90°) in the stacking direction to the first restraining members 16A and 16B, and the battery cell 12. That is, a predetermined binding load can be applied to the battery cells 12 from the stacking direction.

Also, at this time, since the first restraining members 16A and 16B are attached to the entire end surfaces of the battery cells 12, the surface pressure acting on the battery cells 12 becomes uniform.

Furthermore, the battery cells 12 may shrink due to repeated charging and discharging, and the restraining (stacking direction) load acting on the battery cells 12 may decrease. ) follows the contraction of the battery cell 12 and is guided by the linear guide 110 to move leftward (arrow Y1 direction). As a result, the inclined surfaces 40A, 40B, 42A, 42B of the battery cell unit 44 (first restraining members 16A, 16B) and the inclined surfaces 56A, 56B, 66A of the second restraining member 18 and the third restraining member 20 are formed. , 66B are maintained. That is, it is possible to prevent or suppress a decrease in stacking direction (restraining) load acting on the battery cells 12 from the second restraining member 18 and the third restraining member 20 via the first restraining members 16A and 16B.

By the way, in the battery stack 10, the inclined surfaces 42B, 42A of the first restraining members 16B, 16A attached to the end plates 14A, 14B correspond to the inclined surfaces 66B of the projections 60 at both ends of the third restraining member 20 in the stacking direction. , 66A are respectively abutted. However, when the battery cells 12 contract, the battery cells 12A and 12B attached to the end plates 14A and 14B also contract, and the inclined surfaces 66B and 66A of the first restraining members 16B and 16A retreat outward in the stacking direction. Displacement of the third restraining member 20 is allowed.

In addition, when the battery cells 12 are stacked in the stacking direction via a resin frame and a binding load is applied in the stacking direction, there is a risk that the restraining load acting on the battery cells 12 may decrease due to creep of the resin frame. However, even if the first restraining members 16A, 16B, the second restraining member 18, and the third restraining member 20 are made of resin and deformed due to creep, the pressure means 22 (coil spring 108 ) moves, the creep of the first restraining members 16A and 16B, the second restraining member 18, and the third restraining member 20 acts on the battery cell 12. It is possible to prevent or suppress the reduction of the restrained load that is applied.

In addition, since the battery cell units 44 are spaced apart from each other in the stacking direction, the battery cells 12 can be cooled well.

[Second embodiment]
A battery stack 200 according to the second embodiment will be described with reference to FIG. In addition, the same reference numerals are given to the same components as in the first embodiment, and detailed description thereof will be given.

In the first embodiment, one battery cell unit 44 is inserted into each recessed portion 52, 62 of the second restraining member 18 and the third restraining member 20 for positioning. 200 has recesses 52A and 62A into which a plurality of battery cell units 44 are inserted.

That is, as shown in FIG. 5, in the battery stack 200, a concave portion 52A into which three battery cell units 44 can be inserted (positioned) into one stacking direction end portion (an arrow X1 direction side end portion) of the second restraining member 18. are formed, and a plurality of recesses 52 are formed on the other end side in the stacking direction.

The recess 52A is formed by extending the stacking direction distance of the bottom surface 54A compared to the bottom surface 54 of the recess 52, and the protrusions 50 forming the recess 52A have the same shape as the protrusions 50 forming the other recesses 52. is.

Similarly, in the battery stack 200, a concave portion 62A into which three battery cell units 44 can be inserted (positioned) is formed at one end in the stacking direction (the end on the arrow X1 direction) of the third restraining member 20. , a plurality of recesses 62 are formed on the other end in the stacking direction (the end in the arrow X2 direction).

The recess 62A is formed by extending the stacking direction distance of the bottom surface 64A compared to the bottom surface 64 of the recess 62, and the protrusions 50 forming the recess 62A have the same shape as the protrusions 50 forming the other recesses 62. is.

In the recess 52A of the second restraining member 18 and the recess 62A of the third restraining member 20 formed in this manner, the three battery cell units 44A to 44C are stacked (contacted) in the stacking direction. inserted. Of the battery cell units 44, the inclined surface 42A of the battery cell unit 44A closest to one end in the stacking direction (arrow X1 direction) is in contact with the inclined surface 202A of the recess 52A, and is closest to the other end in the stacking direction (arrow X2). The inclined surface 42B of the battery cell unit 44C at the end of the direction side) abuts against the inclined surface 202B of the recess 52A.

Note that the inclined surfaces 202A and 202B correspond to the "second inclined surface".

Similarly, among the battery cell units 44 inserted into the recesses 62A, the inclined surfaces 42A of the battery cell units 44 closest to one end in the stacking direction (arrow X1 direction side) are brought into contact with the inclined surfaces 204A of the recesses 62, The inclined surface 42B of the battery cell unit 44 at the end closest to the other end in the stacking direction (arrow X2 direction side) abuts against the inclined surface 204B of the recess 62 .

Note that the inclined surfaces 204A and 204B correspond to the "second inclined surface".

In this way, it is also possible to form recesses 52A and 62A capable of restraining a plurality of battery cell units 44 in the second restraining member 18 and the third restraining member 20 and restrain them.

By configuring the battery stack 200 in this manner, the same effect as the battery stack 10 can be obtained, and the battery stack 200 can be formed more compactly than the battery stack 10 .

[Third embodiment]
A battery stack 300 according to the third embodiment will be described with reference to FIG. In addition, the same reference numerals are given to the same components as in the first embodiment, and detailed description thereof will be given.

In this battery stack 300, cooling holes 302 and 304 extending in the vertical direction (direction of arrow Z) are formed in the projections 50 and 60 of the second restraining member 18 and the third restraining member 20, respectively. Refrigerant is passed through each of the cooling holes 302 and 304 .

In addition, a gap 306 between the battery cell units 44 positioned in the stacking direction in the case 26 by the second restraining member 18 and the third restraining member 20 and the end plates 14A and 14B. A coolant is caused to flow vertically through the gaps 308 and 310 between the first restraining members 16B and 16A and the battery cell unit 44 .

In this way, in the battery stack 300, the gaps 306 between the battery cell units 44 arranged at predetermined intervals in the stacking direction, the end By flowing a coolant through the gaps 308, 310 between the first restraining members 16B, 16A attached to the plates 14A, 14B and the battery cell unit 44, and provided in the second restraining member 18, the third restraining member 20 By flowing a coolant through the cooling holes 302 provided, the battery cell unit 44 (battery cell 12) and the battery cells 12A and 12B attached to the end plates 14A and 14B can be effectively cooled.

[others]
In addition, in the first to third embodiments, the coil spring 108 is used as a means for generating a biasing force in the pressurizing means 22 of the battery stacks 10, 200, 300. However, as shown in FIG. good.

In addition, in the third embodiment, the coolant flows through the gaps 306, 308, and 310 of the battery stack 300, and also flows through the cooling holes 302 formed in the second restraining member 18 and the third restraining member 20. However, either one of them may be used.

Furthermore, in the first to third embodiments, the third restraining member 20 can be displaced in the left-right direction by the linear guide 110, but the third restraining member 20 may be guided in the left-right direction by a guide block or the like. .

Further, in the battery stack 300 of the third embodiment, a structure for flowing a coolant is added to the battery stack 10 of the first embodiment, but a structure for flowing a coolant is added to the battery stack 200 of the second embodiment. Anything is fine.

Furthermore, in the first to third embodiments, the positioning of the second restraining member 18 and the third restraining member 20 in the stacking direction is determined by the inclined surfaces 40A of the first restraining members 16B and 16A attached to the end plates 14A and 14B. , 40B, 42A, and 42B, but other means may be used for positioning in the stacking direction.

Although the embodiment has been described above, it is needless to say that the invention can be embodied in various forms without departing from the gist of the invention.

10, 200, 300 battery stack 12 battery cells 14A, 14B end plates 16A, 16B first restraining member 18 second restraining member 20 third restraining member (second restraining member)
40A, 40B, 42A, 42B Inclined surface (first inclined surface)
52, 62, 52A, 62A recesses 56A, 56B, 66A, 66B, 202A, 202B, 204A, 204B inclined surfaces (second inclined surfaces)

Claims (1)

a plurality of substantially rectangular battery cells;
Attached to both end surfaces of the battery cell in the stacking direction, respectively, at both end portions in the orthogonal direction perpendicular to the stacking direction of the battery cell, forming a predetermined angle with the stacking direction toward the end portion in the orthogonal direction. a pair of first restraining members respectively formed with a pair of first inclined surfaces inclined to the side;
A pair of second slanted surfaces corresponding to the first slanted surfaces of the set of first restraining members, into which the battery cell and the orthogonal direction end portions of the set of first restraining members are inserted A set of second restraining members each having a recess formed with
an urging member capable of applying a load in the orthogonal direction to the second restraining members to cause the pair of second restraining members to approach each other and being elastically deformable in the orthogonal direction; a load applying means;
a battery stack.