JP2015011819A - Electricity storage device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fixing structure facilitating the positioning and mounting of an electricity storage module and a case while achieving fixation of the electricity storage module to the case, the electricity storage module having a reduced length of an electricity storage device in a lamination direction.SOLUTION: An electricity storage device includes: an electricity storage module in which a plurality of electricity storage elements are disposed in line in a predetermined direction and a pair of end plates sandwiching the electricity storage elements in the predetermined direction are provided; a fixing part which is provided in a case for accommodating the electricity storage module to fix the end plates and the case with a fastening bolt; and a bolt insertion hole of the fastening bolt, which is formed in the end plates and extending from a first surface in contact with the fixing part toward a second surface facing the first surface. The fixing part corresponding to at least one of the pair of end plates is provided movably in the predetermined direction relative to the bolt insertion hole. The electricity storage device further includes a positioning mechanism for aligning, in the predetermined direction, the bolt insertion hole with a bolt hole of the fixing part movable in the predetermined direction.

Description

  The present invention relates to a fixing structure of a power storage device that fixes a power storage module in which a plurality of power storage elements are stacked to a case.

  In the battery pack of Patent Document 1, a battery module in which a plurality of batteries are stacked is fixed to a lower case via a bracket. The bracket is arrange | positioned on the outer side of the end plate arrange | positioned at the lamination direction both ends of a battery module. The bracket is fixed to the lower case at a fastening position outside the end plate in the stacking direction, whereby the battery module is fixed to the lower case.

JP 2008-277050 A JP 2009-070669 A JP 2010-225435 A

  However, when the fastening positions are provided outside the end plates at both ends in the stacking direction of the battery module as in Patent Document 1, the length of the entire battery pack in the stacking direction becomes long, and the entire battery pack is reduced in size. It is difficult.

  In addition, a battery module configured by stacking a plurality of batteries has variations in the length in the stacking direction (length direction). For such a variation in length, for example, as in Patent Document 2, a bolt hole can be formed in a long hole shape, and the movement of the bolt in the stacking direction can be allowed along the bolt hole. .

  However, the fixing structure of Patent Document 2 is not a structure in which the bolt holes on the battery module side and the bolt holes on the lower case side coincide with each other in the stacking direction. For this reason, in order to allow variation in the length of the battery module in the stacking direction, the length of the battery pack in the stacking direction is increased by the amount of the bolt hole formed in the shape of a long hole. In addition, even if the bolt hole of the lower case is formed into a long hole shape, the battery module bolt hole must be positioned with respect to the long hole bolt hole, and the assembly work is easy. It's hard to say.

  Accordingly, an object of the present invention is to provide a power storage device in which a power storage module in which a plurality of power storage elements are stacked is housed in a case, while realizing the fixing of the power storage module to the case while suppressing the length of the power storage device in the stacking direction, An object of the present invention is to provide a power storage device having a fixing structure in which the power storage module and the case can be easily positioned and assembled.

  A power storage device according to a first invention of the present application includes a power storage module in which a plurality of power storage elements are arranged in a predetermined direction and a pair of end plates sandwiching the plurality of power storage elements in the predetermined direction are provided. A fixing portion for fixing the end plate and the case with a fastening bolt, and a first surface formed on the end plate and in contact with the fixing portion toward a second surface facing the first surface. And a bolt insertion hole of the extending fastening bolt.

  The fixing portion corresponding to at least one of the pair of end plates is provided so as to be movable in a predetermined direction with respect to the bolt insertion hole, and the power storage device is movable in a predetermined direction with respect to the bolt insertion hole. And a positioning mechanism for aligning the bolt holes of the fixed portions in a predetermined direction.

  According to the first invention of the present application, the end plate is fixed to the case with the fastening bolt through the bolt insertion hole extending from the first surface in contact with the fixing portion to the second surface facing the first surface in the end plate. Therefore, the fastening position between the power storage module and the lower case becomes the installation position of the end plates that constitute both ends of the power storage module, and the fixing of the power storage device to the case in which the length in the stacking direction is suppressed is realized. In addition, the positioning mechanism can align the bolt holes on the case side with the bolt holes (bolt insertion holes) on the power storage module side, allowing the case to store power in the case while allowing variations in the stacking direction length of the power storage modules. Modules can be assembled easily.

  The positioning mechanism can be composed of a first positioning portion provided on the fixed portion and a second positioning portion provided on the end plate. At this time, the positioning mechanism is configured such that the first positioning portion and the second positioning portion are located outside the end plate in the predetermined direction when the fixing portion is moved in the predetermined direction with the power storage module provided in the case. It can form in the fitting structure (1st fitting structure) which mutually fits in an end surface. With this configuration, the bolt insertion hole and the bolt hole can be matched in a predetermined direction in a state where the power storage module is provided in the case, and the variation in the stacking direction length of the power storage modules is allowed. The power storage module can be easily assembled to the lower case.

  Further, the fixed portion can be configured to be movable in a direction orthogonal to a predetermined direction. At this time, the second positioning portion contacts the first positioning portion with respect to the movement of the fixing portion in a predetermined direction, and the bolt insertion hole and the bolt hole of the fixing portion coincide with each other in a direction orthogonal to the predetermined direction. It can comprise so that it may have a guide surface for making it. By comprising in this way, a bolt hole can be made to correspond with a bolt insertion hole in a predetermined direction and the direction orthogonal to a predetermined direction, and an electrical storage module can be easily assembled | attached with respect to a case. .

  In the positioning mechanism including the first positioning portion provided in the fixing portion and the second positioning portion provided in the end plate, the first positioning portion and the second positioning portion are mutually connected in the direction in which the bolt insertion hole extends. It can form in the fitting structure (2nd fitting structure) which fits together. When the power storage module is provided in the case, the fixing portion is arranged in a predetermined direction with respect to the end plate by a fitting structure in a direction in which the bolt insertion hole extends so that the bolt insertion hole and the bolt hole are aligned in a predetermined direction. Moving. When the power storage module is provided in the case, the fixing portion moves in a predetermined direction by the fitting structure in the direction in which the bolt insertion hole extends, and the bolt insertion hole and the bolt hole can be automatically matched in the predetermined direction. Therefore, the power storage module can be easily assembled to the lower case while allowing variations in the length of the power storage modules in the stacking direction.

  In the second fitting structure, the second positioning portion contacts the first positioning portion when the power storage module is provided in the case, and matches the bolt insertion hole and the bolt hole of the fixing portion in a predetermined direction. Therefore, it can be configured to have a first guide surface. Further, the second positioning portion is configured to have a second guide surface for contacting the first positioning portion and aligning the bolt insertion hole and the bolt hole of the fixing portion in a direction orthogonal to the predetermined direction. Can do. By comprising in this way, a bolt hole can be made to correspond with a bolt insertion hole in a predetermined direction and the direction orthogonal to a predetermined direction, and an electrical storage module can be easily assembled | attached with respect to a case. .

  The case may be provided between the case and the first surface of the end plate, and a pedestal on which the fixing portion is disposed may be provided. The pedestal may be provided between the first surface of the end plate and the fixed portion, and may include a contact portion that contacts the first surface of the end plate. A first opening corresponding to the bolt hole of the fixing part and a second opening corresponding to the positioning mechanism can be formed in the contact part. And each of the 1st opening and the 2nd opening can be constituted in the shape of a slot in a predetermined direction. With this configuration, the fixing portion can be provided so as to be movable in a predetermined direction with respect to the end plate, and the bolt insertion hole and the bolt hole can be provided while allowing variation in the stacking direction length of the power storage module. The power storage modules can be easily assembled to the case by matching them in a predetermined direction.

  In the above power storage device, the power storage module may be configured to include an auxiliary member that is disposed between the pair of end plates and provided to be sandwiched between the power storage elements along with the power storage elements. The auxiliary member is provided with a bolt insertion hole for a fastening bolt extending from the third surface in contact with the fixing portion toward the fourth surface facing the third surface, and the pair of end plates and the auxiliary member are interposed via the fixing portion. It can be configured to be fixed to the case. At this time, the two fixing portions corresponding to each of the pair of end plates are provided in the case so as to be movable in a predetermined direction with respect to the bolt insertion holes, and the fixing portions corresponding to the auxiliary members are fixedly arranged with respect to the case. Configured to be By configuring in this way, even if the length of the power storage module in a predetermined direction is increased, the region between the end plates is fixed to the case by the auxiliary member. It is possible to easily assemble a power storage module that allows variations in the length in the stacking direction of the modules.

It is a block diagram of the battery pack of Example 1, and is an exploded perspective view of the battery case and the assembled battery constituting the battery pack. 3 is a side view of the battery pack of Example 1. FIG. It is a figure for demonstrating the fixation structure and positioning mechanism (1st fitting structure) of the assembled battery and lower case of Example 1. FIG. 2 is a diagram illustrating an example of an assembled battery in a state assembled to the lower case of Example 1. FIG. FIG. 6 is a diagram for explaining a process of assembling the assembled battery to the lower case in the fixing structure and the positioning mechanism (first fitting structure) of Example 1. It is a figure which shows the state which mounted the battery pack of Example 1 in the vehicle. It is a figure for demonstrating the fixation structure and positioning mechanism (2nd fitting structure) of the assembled battery and lower case of Example 1. FIG. In the positioning mechanism (2nd fitting structure) of Example 1, it is a figure which shows the relationship between a bolt insertion hole and a bolt hole, and a positioning mechanism. FIG. 6 is a diagram for explaining a process of assembling the assembled battery to the lower case in the fixing structure and the positioning mechanism (second fitting structure) of Example 1. It is a figure which shows the aspect which provided one fixed part movably among the fixed parts corresponding to a pair of end plate which comprises the assembled battery of Example 1. FIG. FIG. 3 is a diagram for explaining a fixing structure between a battery pack and a lower case in which an auxiliary member is arranged at a central portion in the stacking direction of the first embodiment. It is a structure perspective view of the end plate which concerns on a modification. It is a top view of the end plate which concerns on a modification.

  Examples of the present invention will be described below.

Example 1
A battery pack (corresponding to a power storage device) that is Embodiment 1 of the present invention will be described with reference to FIGS. FIG. 1 is a configuration diagram of a battery pack 1 according to the present embodiment. 1 to 13, the X axis, the Y axis, and the Z axis are axes that are orthogonal to each other. In this embodiment, the axis corresponding to the vertical direction is the Z axis.

  The battery pack 1 of the present embodiment can be mounted on a vehicle. Vehicles include hybrid cars and electric cars. A hybrid vehicle is a vehicle including a fuel cell and an internal combustion engine in addition to the battery pack 1 as a power source for running the vehicle. An electric vehicle is a vehicle including only the battery pack 1 as a power source. The electric energy can be stored in the battery pack 1 by converting the kinetic energy generated during braking of the vehicle into electric energy using the motor / generator.

  The battery pack 1 includes a battery pack (corresponding to a power storage module) 10 in which a plurality of single cells (corresponding to power storage elements) 11 are electrically connected, and a battery case 2 that houses the battery pack 10. Is done.

  The battery case 2 includes an upper case 21 and a lower case 22. The assembled battery 10 of the present embodiment is fixed to the lower case 22 via the fastening bolts B, and the upper case 21 is assembled from above the assembled battery 10 so as to cover the assembled battery 10 fixed to the lower case 22. The upper case 21 and the lower case 22 are fixed to each flange 23 with a fastening bolt (not shown).

  The assembled battery 10 can be configured by electrically connecting a plurality of unit cells 11 arranged side by side in the Y direction. The assembled battery 10 is formed in a long shape by laminating a plurality of single cells 11 in the Y direction. The Y direction is a direction in which the plurality of single cells 11 constituting the assembled battery 10 are stacked, and is the longitudinal direction of the assembled battery 10.

  In the assembled battery 10, a pair of end plates 12 are disposed at both ends in the Y direction (both ends of the plurality of single cells 11). A restraining member 13 extending in the Y direction is connected to the pair of end plates 12. The restraining member 13 is disposed on the side surface in the X direction orthogonal to the stacking direction, that is, on the left and right side surfaces of the assembled battery 10 when viewed in the stacking direction. By fixing both ends of the restraining member 13 to the pair of end plates 12, restraining force can be applied to the plurality of single cells 11 constituting the assembled battery 10. The binding force is a force that sandwiches the cell 11 in the Y direction.

  A connecting portion 12b to which the restraining member 13 is connected is provided on the end surface 12a facing the outer side of the end plate 12 in the Y direction. For example, two connecting portions 12b are provided on the end surface 12a so as to be spaced apart in the vertical direction (Z direction) corresponding to the two restraining members 13, and the fixing portion 13a at the end of the restraining member 13 in the Y direction, a fastening bolt, and the like. It is fixed with.

  The fixed portion 13a is bent in the X direction so that the end portions of the restraining member 13 arranged so that the left and right side surfaces of the assembled battery 10 extend in the stacking direction (Y direction) are brought into contact with the end surface 12a of the end plate 12. Can be formed.

  Further, as shown in FIG. 1, in this embodiment, two restraining members 13 are arranged on the left and right side surfaces of the assembled battery 10. Each of the end surfaces 12 a of the pair of end plates 12 corresponds to the two connecting portions 12 b corresponding to the two restraining members 13 on the right side of the assembled battery 10 and the two restraining members 13 on the left side of the assembled battery 10. Two connecting portions 12b are provided.

  In addition, the number of the restraint members 13, its cross-sectional shape, and the number of the connection parts 12b can be set suitably. The cross-sectional shape of the restraining member 13 is a shape in a cross section orthogonal to the longitudinal direction of the restraining member 13. The restraint member 13 only needs to be able to generate restraint force by being connected to the pair of end plates 12. Moreover, although the example in which the fixing portion 13a of the restraining member 13 is connected to the end surface 12a facing the outer side in the Y direction of the end plate 12 is shown, this is not restrictive. For example, the connecting portions 12 b may be formed on the left and right side surfaces of the end plate 12 in the X direction, and the restraining member 13 may be disposed on the pair of end plates 12.

  As the cell 11, a secondary battery such as a nickel metal hydride battery or a lithium ion battery can be used. An electric double layer capacitor (capacitor) can be used instead of the secondary battery. The number of the single cells 11 constituting the assembled battery 10 can be set as appropriate.

  The unit cell 11 has a rectangular outer shape having a longitudinal direction in the X direction. On the upper end surface in the vertical direction, a positive electrode terminal 11a and a negative electrode terminal 11b are provided separately in the X direction. The positive electrode terminal 11a is connected to the positive electrode of the power generation element housed in the case constituting the exterior of the unit cell 11, and the negative electrode terminal 11b is connected to the negative electrode of the power generation element.

  In two unit cells 11 adjacent in the Y direction, the positive terminal 11a of one unit cell 11 is electrically connected to the negative terminal 11b of the other unit cell 11 through a bus bar (not shown). The plurality of single cells 11 arranged side by side in the Y direction are electrically connected in series by a bus bar, and the positive terminals 11a of one single cell 11 located at both ends in the stacking direction of the assembled battery 10 are the positive electrodes of the assembled battery 10. The negative electrode terminal 11 b of the other unit cell 11 becomes the negative electrode terminal of the battery pack 10.

  In this embodiment, all the unit cells 11 are electrically connected in series. However, the present invention is not limited to this. Specifically, a plurality of unit cells 11 electrically connected in parallel may be included.

  Next, the structure for fixing the battery case 2 and the assembled battery 10 of this embodiment will be described in detail. FIG. 2 is a side view of the battery pack 1. FIG. 3 is a view for explaining the fixing structure and positioning mechanism (first fitting structure) of the assembled battery 10 and the lower case 22. FIG. 4 is a diagram illustrating an example of the assembled battery 10 in a state assembled to the lower case 22.

  As shown in FIG. 2, the end plate 12 disposed at both ends in the Y direction and the fixing portion 200 of the lower case 22 are fixed with fastening bolts B, and the assembled battery is mounted on the lower case 22 on which the assembled battery 10 is mounted. 10 is fixed.

  The end plate 12 of the present embodiment is formed in a long shape in the X direction with a length corresponding to the shape of the unit cell 11, and has a predetermined thickness in the Y direction. The end plate 12 is directed from the upper end surface 12c of the end plate 12 toward the fixed portion 200 positioned below, in other words, from the lower end surface 12d (corresponding to the first surface) contacting the fixed portion 200 of the end plate 12. A bolt insertion hole 12e of the fastening bolt B extending toward the upper end surface 12c (corresponding to the second surface) facing the end surface 12d is provided.

  The bolt insertion hole 12e is an insertion hole penetrating from the upper end surface 12c to the lower end surface 12d in the Z direction, and is formed inside the end plate 12 in the thickness in the Y direction. The diameter of the bolt insertion hole 12e is formed to a size corresponding to the diameter of the shaft portion of the fastening bolt B, and two or more can be provided in the end plate 12 apart in the X direction (length direction).

  The lower case 22 is provided with fixed portions 200 at positions corresponding to the end plates 12 at both ends in the Y direction of the assembled battery 10 (see FIG. 2). The fixing portion 200 has a bolt hole 201 corresponding to the bolt insertion hole 12e of the end plate 12 formed on the upper surface. The fixing portion 200 is formed in a size corresponding to the shape of the end plate 12 (lower end surface 12d), and has a long shape in the X direction and a predetermined thickness in the Y direction. The bolt holes 201 are arranged in accordance with the distance between the two bolt insertion holes 12e of the end plate 12 in the length direction (X direction) of the fixed portion 200, respectively.

  The lower case 22 is provided with a pedestal 210 on which the end plate 12 of the assembled battery 10 is placed, and the fixed portion 200 is disposed on the pedestal 210. The pedestals 210 correspond to the pair of end plates 12 at both ends of the assembled battery 10 and are disposed on the bottom surface 22a of the lower case 22 so as to be separated from each other in the Y direction (stacking direction).

  The pedestal 210 is located on the upper surface side where the bolt hole 201 of the fixing portion 200 is formed, that is, between the lower end surface 12d of the end plate 12 and the fixing portion 200, and is placed in contact with the lower end surface 12d of the end plate 12. A portion 211 (corresponding to a contact portion) is included. The pedestal 210 is fixed to the lower case 22 by welding or the like while forming an arrangement space S in which the fixing part 200 is arranged below the mounting part 211.

  As shown in FIG. 2, in the pedestal 210, both ends of the mounting portion 211 in the Y direction are fixed to the bottom surface 22 a of the lower case 22 and the Y direction side surface 22 b of the lower case 22 by welding or the like. At this time, the arrangement space S of the fixing portion 200 formed by the base 210 has a rectangular cross-sectional shape surrounded by the mounting portion 211, the bottom surface 22a of the lower case 22, and the Y-direction side surface 22b. The pedestal 210 of this embodiment functions as a reinforcing member that extends over the bottom surface 22a and the Y-direction side surface 22b of the lower case 22, and improves the strength of the lower case 22.

  The length of the arrangement space S in the X direction is equal to or longer than the length of the fixed portion 200 (end plate 12) in the X direction, and the length in the Y direction is larger than the width of the fixed portion 200 in the Y direction. Is also formed long. In the arrangement space S, the fixing part 200 is arranged so that the longitudinal direction is substantially horizontal with the longitudinal direction of the end plate 12 arranged in the mounting part 211, and the longitudinal direction is substantially parallel to the Y direction. The fixed part 200 is arranged to be movable by a predetermined distance in the Y direction (stacking direction).

  Thus, the fixing portion 200 of the present embodiment is movable in the Y direction with respect to the bolt insertion hole 12e when the end plate 12 (the assembled battery 10) is mounted on the lower case 22 via the base 210. The lower case 22 is disposed. The fixing portion 200 is moved substantially parallel to the Y direction with respect to the bolt insertion hole 12e of the end plate 12 mounted on the mounting portion 211 of the base 210, so that the bolt hole 202 coincides with the bolt insertion hole 12e in the Y direction. Can be made.

  As shown in FIG. 3, the mounting portion 211 of the base 210 has two openings 212 (corresponding to the first opening) corresponding to the bolt holes 201 of the fixing portion 200. The opening 212 exposes the bolt hole 201 of the fixing portion 200 located below the mounting portion 211 to the end plate 12 toward the lower end surface 12d, and the fastening bolt B inserted into the bolt insertion hole 12e of the end plate 12 is provided. This is an opening through which the bolt hole 201 is inserted.

  The opening 212 can be formed in a long hole shape in the Y direction. This is for the purpose of positioning the fixing portion 200 with the bolt insertion hole 12e so that the bolt hole 201 is exposed to the bolt insertion hole 12e even if the fixing portion 200 moves in the Y direction while keeping the longitudinal direction substantially parallel. . Therefore, in the arrangement space S, the fixing portion 200 is arranged so as to be able to move a distance corresponding to the length in the Y direction of the opening 212 formed in the shape of a long hole.

  In this embodiment, a positioning mechanism 220 for aligning the bolt hole 201 and the bolt insertion hole 12e in the Y direction is provided. The positioning mechanism 220 causes the end plate 12 and the fixing portion 200 to abut each other so that the bolt hole 202 of the fixing portion 201 matches the bolt insertion hole 12e in the Y direction.

  Specifically, as shown in FIG. 3, the positioning mechanism 220 includes a convex portion 221 (corresponding to the first positioning portion) provided in the fixing portion 200 and a concave portion 222 (second second) provided in the end plate 12. Corresponding to the positioning portion). Then, when the assembled battery 10 is mounted on the lower case 22 (mounting section 211), when the fixing section 200 is moved in the Y direction so as to contact the end plate 12, the convex section 221 and the concave section 222 has a fitting structure (first fitting structure) that fits to each other on the outer end surface 12a in the Y direction of the end plate 12. The positioning mechanism 220 of the present embodiment makes the bolt hole 201 coincide with the bolt insertion hole 12e in the Y direction by the fitting structure of both.

  As an example, the convex portion 221 of the fixed portion 200 can be formed in a triangular prism shape that extends vertically upward from the upper surface 200a of the fixed portion 200 in the Z direction. The convex portion 221 includes a vertical surface 221a that is substantially parallel to the end surface 12a of the end plate 12 and has a predetermined width in the X direction, and two inclined surfaces 221b that extend from the vertical surface 221a in the Y direction.

  The vertical surface 221a and the inclined surface 221b are flat surfaces perpendicular to the Z direction and have a predetermined width. The convex portion 221 has a triangular shape in which the cross-sectional shape of the XY plane is surrounded by the vertical surface 221a and the inclined surface 221b. A top portion 221c formed by the two inclined surfaces 221b protrudes substantially perpendicularly from the vertical surface 221a so as to go to the concave portion 222 of the end plate 12.

  The mounting portion 211 has an opening 213 (corresponding to a second opening) corresponding to a convex portion 221 that extends vertically upward from the upper surface 200a of the fixed portion 200 in the Z direction. The opening 213 is an opening for exposing the convex portion 221 extending upward in the Z direction from below the mounting portion 211 so as to face the end surface 12a of the end plate 12 in the Y direction. Similarly to the opening 212, the opening 213 can be formed in a long hole shape in the Y direction. By comprising in this way, it can accept | permit that the fixing | fixed part 200 moves to a Y direction for positioning with the volt | bolt penetration hole 12e.

  The concave portion 222 of the end plate 12 is formed on the end surface 12 a according to the shape of the convex portion 221 so as to have a fitting structure with the convex portion 221. The concave portion 222 fitted to the convex portion 221 has a concave surface 222a that is recessed from the end surface 12a in the Y direction. The concave surface 222a is inclined in a direction recessed from the end surface 12a toward the inside of the end plate 12, and is an inclined surface corresponding to the inclined surface 221b of the convex portion 221.

  The concave surface 222a is formed with a top portion 222b corresponding to the top portion 221c of the triangular prism-shaped convex portion 221, and the inclined surface 221b and the concave surface 222a are formed as surfaces inclined at the same inclination angle in the Y direction. When the convex portion 221 is fitted to the concave portion 222, the inclined surface 221b and the concave surface 222a are in contact with each other, the top portion 221c and the top portion 222b are in contact with each other, and the movement of the fixed portion 200 toward the end plate 12 in the Y direction is performed. Be blocked.

  At this time, as shown in FIG. 3, the positioning mechanism 220 has a distance d1 between the center axis of the bolt insertion hole 12e and the top 222b of the recess 222 in the Y direction, and the center axis of the bolt hole 201 and the top 221c of the projection 221. The distance d2 is set to be the same. Therefore, the top portion 221c of the convex portion 221 is in contact with the top portion 222b of the concave portion 222 and is prevented from moving toward the end surface 12a of the fixing portion 200, in other words, the concave and convex portions of the end plate 12 and the fixing portion 200 are in contact with each other. In this state, the bolt hole 201 of the fixing portion 200 matches the bolt insertion hole 12e of the end plate 12 in the Y direction.

  Moreover, the fixing | fixed part 200 can be provided so that a movement in the X direction right and left is possible. As shown in FIG. 1, both ends in the X direction of the fixing unit 200 can be configured not to be blocked by the pedestal 210. Then, by making the X-direction length of the opening 213 larger than the X-direction length of the vertical surface 221a of the convex portion 221, the fixed portion 200 can be moved in the X-direction as well as the Y-direction relative to the base 210. The case 22 can be provided.

  Even in such a case, the positioning mechanism 220 of the present embodiment moves the fixing portion 200 in the X direction by the contact between the inclined surface 221b and the concave surface 222b forming the convex surface, and the bolt hole 201 and the bolt insertion hole. 12e can be matched in the X direction.

  More specifically, the top portion 221c of the convex portion 221 is not located on the same straight line as the top portion 222b of the concave portion 222 in the Y direction, and is displaced toward the end surface 12a of the end plate 12 when shifted in the X direction. When the fixing portion 200 moves, the top portion 221c of the convex portion 221 contacts the concave surface 222b.

  At this time, the concave surface 222a guides the top part 221c of the convex part 221 moving in the Y direction in the X direction toward the top part 222b. Therefore, the concave surface 222a of the concave portion 222 serves as a guide surface for guiding the top portion 221 of the convex portion 221 moving in the Y direction in the X direction so that the bolt insertion hole top portion 222b and the top portion 221c are on the same straight line in the Y direction. The bolt hole 201 and the bolt insertion hole 12e can be matched in the X direction.

  As described above, in this embodiment, the fixing portion 200 arranged in the lower case 22 is provided so as to be movable in the Y direction and the X direction with respect to the end plate 12 placed on the placement portion 211, and is positioned by the positioning mechanism 220. The bolt hole 201 and the bolt insertion hole 12e can be easily matched in the Y direction and the X direction.

  The opening 213 is formed to be slightly larger than the cross-sectional shape of the XY plane of the convex portion 221 in the X direction in order to allow the convex portion 221 to move in the Y direction. That is, when the opening 213 is formed to be slightly wider in the X direction with a predetermined dimensional tolerance in order to allow movement of the fixed portion 200 in the Y direction, the fixed portion 200 is allowed to move in the X direction. And placed on the pedestal 210. In addition to intentionally allowing movement in the X direction, in this embodiment, the bolt hole 201 and the bolt insertion hole 12e can be easily matched in the Y direction and the X direction.

  FIG. 4 is a diagram illustrating the assembled battery 10 in a state assembled to the lower case 22. As shown in FIG. 4, when the fixed portion 200 is moved toward the end surface 12a in a state where the end plate 12 is mounted on the mounting portion 211 of the base 210, the convex portion 221 constituting the positioning mechanism 220 becomes Y It fits into the recess 222 in the direction, and the top 221 c of the projection 221 contacts the top 222 b of the recess 222. In this state, the bolt hole 201 of the fixing portion 200 matches the bolt insertion hole 12e of the end plate 12 in the Y direction and the X direction.

  Then, after the bolt insertion hole 12e and the bolt hole 201 are matched in the Y direction, the fastening bolt B is inserted into the insertion hole 12e, and the end plate 12 and the fixing portion 200 are fastened.

  Thus, the fixing structure of the present embodiment is such that the end plate 12 is lower via the bolt insertion hole 12e extending from the lower end surface 12d contacting the fixing portion 200 of the end plate 12 toward the upper end surface 12c facing the lower end surface 12d. Since it is fixed to the case 22 with the fastening bolt B, the fastening position of the assembled battery 10 and the lower case 22 becomes the mounting position (installation position) of the end plate 12 that constitutes both ends of the assembled battery 10, and the battery pack 1 Fixation to the battery case 2 with a reduced length in the Y direction (stacking direction) is realized.

  The positioning mechanism can make the bolt hole 201 on the lower case 22 side coincide with the bolt insertion hole 12e on the assembled battery 10 side, and allow variations in the length of the assembled battery 10 in the Y direction, while lower case 22 is allowed. In contrast, the assembled battery 10 can be easily assembled.

  When the end plate 12 and the fixing portion 200 are fastened by the fastening bolt B, the fixing portion 200 rotates in the XY plane by screwing the fastening bolt B, and the positions of the other bolt insertion hole 12e and the bolt hole 201 are displaced. May end up.

  For this reason, in the present embodiment, the convex portion 221 of the positioning mechanism 220 is formed in a region between two bolt holes 201 that are separated in the X direction. When the fastening bolt B is inserted into one of the bolt insertion holes 12e and fastened with the fixing portion 200, the fixing portion 200 is formed in the region between the bolt holes 201 even if the fixing portion 200 tries to rotate in the XY plane by screwing the fastening bolt B. The fitting mechanism positioning mechanism 220 prevents rotation of the fixing portion 200 in the XY plane, and can suppress displacement between the other bolt insertion hole 12e and the bolt hole 201.

  That is, even if the fixing portion 200 tries to rotate clockwise around one bolt hole 201, the convex portion 221 of the fixing portion 200 is in contact with the concave portion 222 of the end plate 12 due to the fitting structure. Therefore, the rotation is prevented, and the positional deviation between the other bolt insertion hole 12e and the bolt hole 201 is suppressed.

  Further, in the example shown in FIG. 4, the concave portion 222 formed on the end surface 12 a of the end plate 12 and the convex portion 221 formed on the fixing portion 200 are fitted to each other in the Y direction so that the bolt insertion hole 12 e and the bolt hole are In a state in which 201 coincides in the Y direction, a vertical surface 221a corresponding to the end surface of the convex portion 221 in the Y direction is located in substantially the same plane as the end surface 12a of the end plate 12 in the ZX plane. Since the positioning mechanism 220 does not protrude outward on the end surface 12a of the end plate 12, the entire length of the battery pack 1 in the Y direction can be shortened. The same applies even if the vertical surface 221a is configured to be located on the inner side in the Y direction toward the inside of the end plate 12 than the end surface 12a of the end plate 12.

  Next, a method for assembling the assembled battery 10 and the lower case 22 (case 2) of this embodiment will be described. In this assembling method, the end plate 12 is made to correspond to the fixing part 200, and the assembled battery 10 is placed on the lower case 22, and the fixing part 200 is moved after the assembled battery 10 is placed on the lower case 22. The bolt insertion hole 12e and the bolt hole 201 are aligned with each other via the positioning mechanism 220, and the fastening bolt B is inserted into the bolt insertion hole 12e from the upper end surface 12c of the end plate 12 toward the fixing portion 200 positioned below. And a step of fixing the end plate 12 to the lower case 22 by fastening the fastening bolt B inserted through the bolt insertion hole 12e to the fixing portion 200.

  More specific description will be given with reference to FIG. FIG. 5 is a diagram for explaining a method of assembling the assembled battery 10 and the lower case 22 in the fixing structure including the positioning mechanism 220 having the first fitting structure described above.

  As shown in FIG. 5, first, the assembled battery 10 is mounted on the lower case 22 by aligning the end plate 12 with the pedestal 210 on which the fixing portion 200 is disposed (the left diagram in FIG. 5). In a state of being mounted on the mounting portion 211 of the pedestal 210, the convex portion 221 of the fixing portion 200 is located on the outer side in the Y direction than the end surface 12 a of the end plate 12. Further, the assembled battery 10 can be mounted on the pedestal 210 so that the top portion 221c of the convex portion 221 is positioned within the concave surface 222a of the concave portion 222 formed in the end surface 12a of the end plate 12 in the Y direction. .

  Next, in a state where the end plate 12 is mounted on the mounting portion 211 of the base 210, the fixing portion 200 is moved in the Y direction toward the end surface 12a. The convex portion 221 constituting the positioning mechanism 220 is fitted into the concave portion 222 in the Y direction, and the top portion 221c of the convex portion 221 contacts the top portion 222b of the concave portion 222. At this time, even if the convex portion 221 is displaced in the X direction with respect to the concave portion 222, the concave surface 222a is guided in the X direction by moving the top portion 221c of the convex portion 221 moving in the Y direction toward the top portion 222b. In this state, the bolt hole 201 of the fixing portion 200 matches the bolt insertion hole 12e of the end plate 12 in the Y direction and the X direction (center view in FIG. 5).

  Then, after the bolt insertion hole 12e and the bolt hole 201 are made to coincide in the Y direction, the fastening bolts 200 are respectively positioned below the fastening bolts B in the bolt insertion holes 12e opened on the upper end surface 12c of the end plate 12. The end plate 12 and the fixing part 200 are fastened (right diagram in FIG. 5). At this time, the fixing portion 200 is positioned on the lower end surface 12d of the end plate 12 with the mounting portion 211 of the pedestal 210 sandwiched between the fixing portion 200 and the bottom portion 22a of the lower case 22 by being fastened by the fastening bolt B. The end plate 12 (the assembled battery 10) is fixed to the lower case 22 via a pedestal 210 fixed to the lower case 22 by welding or the like.

  FIG. 6 is a diagram illustrating a state in which the battery pack 1 according to the present embodiment is mounted on a vehicle. As shown in FIG. 6, the battery pack 1 can be fixed to the floor panel P of the vehicle with fastening bolts B1. The assembled battery 10 is mounted on the vehicle by being fixed to the vehicle via the case 2 (lower case 22).

  FIG. 6A shows an in-vehicle structure of the battery pack 1 in which the assembled battery 10 is fixed to the lower case 22 by the fixing structure of this embodiment, and FIG. 6B shows a conventional bracket Br. An in-vehicle structure of a battery pack in which the assembled battery 10 is fixed to the lower case 22 is shown. In the example of FIG. 6, by fixing the flanges 23 of the upper case 21 and the lower case 22 to the floor panel P with the fastening bolts B <b> 1, both the upper case 21 and the lower case 22, the battery pack 1 and the floor panel P are fixed. Although the fastening is realized by one fastening part, the present invention is not limited to this, and each fastening part may be fastened by a separate fastening part.

  In FIG. 6B, as described above, the fastening portion of the bracket Br fixed to the end surface 12a of the end plate 12 is located outside the end plates 12 at both ends in the stacking direction of the assembled battery 10 in the Y direction. . The bracket Br is fixed to the lower case 22 by a fastening bolt B at a fastening position outside the end plate 12 in the Y direction. However, in the battery pack 1 of the present embodiment, the fastening position between the assembled battery 10 and the lower case 22 is the mounting position of the end plate 12 that constitutes both ends of the assembled battery 10, and the fixing structure of FIG. In comparison, the battery pack 1 has a fixed structure in which the length in the Y direction (stacking direction) is suppressed.

  In particular, as shown in FIGS. 6A and 6B, in the battery pack 1 of the present embodiment, the fastening position of the assembled battery 10 is farther from the vehicle side portion S in the Y direction. The distance to the battery pack 1 can be increased. That is, the space from the vehicle side part S to the battery pack 1 becomes wide, and the efficiency of the vehicle mounting space of the battery pack 1 can be improved.

  In the positioning mechanism 220 in the above-described fixing structure, a fitting structure in which a concave portion is provided in the fixing portion 200 and a convex portion is provided in the end plate 12 may be employed. Moreover, the shape of the convex part 221 and the recessed part 222 is not limited to a triangular prism shape, and may be an arbitrary polygonal shape or a cylindrical shape. Further, the positioning mechanism 220 in the fixing structure described above may not have a fitting structure when it is mounted on the mounting portion 211 of the pedestal 210 in a state where the positioning in the left and right directions in the X direction is performed. In other words, the bolt insertion hole 12e and the bolt hole 201 can be matched in the Y direction by bringing the convex portion of the fixed portion 200 into contact with the outer end surface 12a of the end plate 12, and in this case, the positioning mechanism 220 is Only the contact portion corresponding to the convex portion (first positioning mechanism) of the fixed portion 200 can be configured, and the end plate 12 can be configured not to include the positioning mechanism.

  FIG. 7 is a view for explaining a fixing structure provided with a positioning mechanism 320 having a second fitting structure.

  As shown in FIG. 7, the positioning mechanism 320 for aligning the bolt hole 201 and the bolt insertion hole 12e in the Y direction brings the end plate 12 and the fixing portion 200 into contact with each other in the same manner as the positioning mechanism 220. Thus, the bolt hole 202 of the fixing portion 201 is aligned with the bolt insertion hole 12e in the Y direction, but the end plate 12 has a fitting structure that fits in the vertical direction.

  In other words, after the end plate 12 is placed on the placement portion 211, the positioning mechanism 220 moves the fixing portion 200 to match the bolt hole 201 and the bolt insertion hole 12e with the fitting structure in the Y direction. When the assembled battery 10 is mounted from above the lower case 22, the positioning mechanism 320 is arranged so that the bolt insertion hole 12 e and the bolt hole 201 coincide with each other in the Y direction (the bolt insertion hole 12 e is The fixing portion 200 is automatically moved in the Y direction with respect to the end plate 22 by the fitting structure in the extending direction) to perform positioning. Hereinafter, the positioning mechanism 320 will be described with a focus on the differences from the positioning mechanism 220, and duplicated description will be given the same reference numerals and description thereof will be omitted.

  The positioning mechanism 320 includes a convex portion 321 (corresponding to the first positioning portion) provided on the upper surface 200a of the fixed portion 200 and a concave portion 322 (corresponding to the second positioning portion) provided on the lower end surface 12d of the end plate 12. ) And can be configured.

  As an example, the convex part 321 of the fixed part 200 can be formed in a quadrangular pyramid shape protruding upward from the upper surface 200a of the fixed part 200 in the Z direction. The convex portion 321 has an inclined surface 321b facing in the Y direction and an inclined surface 321c facing in the X direction, with the top portion 321a protruding in the Z direction from the upper surface 200a.

  In other words, the convex portion 321 has a quadrangular pyramid shape in which the inclined surface 321b and the inclined surface 321c each extend in the Z direction from the rectangular bottom surface on the upper surface 200a of the fixed portion 200, and has a top 321a having a predetermined height from the upper surface 200a. Is formed. A top portion 321a formed by the four inclined surfaces 321b and 321c protrudes substantially vertically from the upper surface 200a so as to go to the concave portion 322 of the end plate 12.

  With respect to the fixed portion 200 disposed below the mounting portion 211 of the pedestal 210, the convex portion 321 is disposed such that the top portion 321 a and the inclined surfaces 321 b and 321 c protrude from the mounting portion 211 through the opening 213. A fitting structure is formed with a recess 322 of the end plate 12, which will be described later.

  The concave portion 322 of the end plate 12 is formed in a shape that is concaved in a quadrangular pyramid shape from the lower end surface 12 d in correspondence with the shape of the convex portion 321 so as to have a fitting structure with the convex portion 321. The concave portion 322 fitted with the convex portion 321 has concave surfaces 322b and 322c that are recessed from the lower end surface 12d in the Z direction. The concave surfaces 322b and 322c are both inclined surfaces that are recessed from the lower end surface 12d toward the inside of the end plate 12, and the concave surface 322b faces in the Y direction and corresponds to the inclined surface 321b of the convex portion 321. The concave surface 322c faces in the X direction and corresponds to the inclined surface 321c of the convex portion 321. One top portion 322a located on the inner side in the Z direction than the lower end surface 12d is formed by four inclined surfaces of concave surfaces 322b and 322c.

  The top portion 322a is a top portion corresponding to the top portion 321a of the triangular pyramid-shaped convex portion 321, and the inclined surface 321bc and the concave surface 322b, and the inclined surface 321c and the concave surface 322c are inclined at the same inclination angle in the Z direction. When the convex portion 321 is fitted into the concave portion 322, the inclined surface 321b and the concave surface 321b are in contact with each other in the Y direction, and the inclined surface 321c and the concave surface 321c are in contact with each other in the X direction. Then, the top part 321a on the fixed part 200 side is guided in the Y direction with respect to the top part 322a on the end plate 12 side, and the fixed part 200 moves in the Y direction so that the top part 321a and the top part 322a coincide with each other in the Y direction. .

  FIG. 8 is a view showing the relationship between the bolt insertion hole 12 e and the bolt hole 201 and the positioning mechanism 320.

  As shown in FIG. 8, the top portion 322a of the recess 322 formed in the end plate 12 is formed so as to coincide with the central axis of the bolt insertion hole 12e in the Y direction. Moreover, the top part 321a of the convex part 321 formed in the fixed part 200 is formed so as to coincide with the central axis of the bolt hole 201 in the Y direction.

  That is, the positioning mechanism 320 fits the top portion 322a that matches the central axis of the bolt insertion hole 12e in the Y direction and the top portion 321a that matches the central axis of the bolt hole 201 in the Y direction by fitting the bolts in the vertical direction. The insertion hole 12e and the bolt hole 201 have a fitting structure that matches in the Y direction.

  Since the top portions 321a and 322a are formed at acute angles, when the top portion 321a and the top portion 322a abut (contact) in the vertical direction, the top portion 321a (fixed portion 200) is restricted from moving in the Y direction. The The top portion 321a on the fixed portion 200 side is guided by the concave surface 322b (corresponding to the first guide surface) and moves in the Y direction with respect to the top portion 322a on the end plate 12 side, and the top portion 321a and the top portion 322a come into contact with each other. In the Y direction, the bolt insertion hole 12e and the bolt hole 201 match in the Y direction.

  Further, in this embodiment, as shown in FIG. 7, the top 322a of the recess 322 and the bolt insertion hole 12e are spaced apart in the X direction by distances d3 and d4, respectively. Correspondingly, the convex portion 321 is formed such that the distance between the top portion 321a of the convex portion 321 and the bolt hole 201 is the distances d3 and d4, respectively.

  For this reason, the positioning mechanism 320 of the present embodiment has a fitting structure in which the bolt insertion hole 12e and the bolt hole 201 match in the X direction when the top portions 321a and 322a are matched by fitting in the vertical direction. The top portion 321a on the fixed portion 200 side is guided by the concave surface 322c (corresponding to the second guide surface) and moves in the X direction with respect to the top portion 322a on the end plate 12 side, and the top portion 321a and the top portion 322a contact each other. The bolt insertion hole 12e and the bolt hole 201 match in the X direction.

  As described above, when the assembled battery 10 is mounted from above the lower case 22, the positioning mechanism 320 moves the fixing portion 200 in the Y direction due to the fitting structure in the vertical direction, and the bolt insertion hole 12 e and the bolt hole 201. Can be automatically matched in the Y direction, so that the positioning step after the assembled battery 10 is mounted on the lower case 22 is not required, and the variation in the Y direction length of the assembled battery 10 is allowed while the lower case is allowed. In contrast, the power storage module can be easily assembled.

  Further, like the positioning mechanism 220, the positioning mechanism 320 is configured such that the fastening position between the assembled battery 10 and the lower case 22 becomes the mounting position of the end plate 12 that constitutes both ends of the assembled battery 10, and the Y direction (stacking) of the battery pack 1. (Direction) can be fixed to the battery case 2 with a reduced length. Moreover, as shown in FIG. 6, the space from the vehicle side part S to the battery pack 1 becomes wide, and the efficiency of the vehicle mounting space of the battery pack 1 can also be achieved.

  In addition, the positioning mechanism 320 has a vertically fitting structure between the end plate 12 and the fixing portion 200 as compared with the positioning mechanism 220, and therefore is fixed between the end surface 12a of the end plate 12 and the side surface 22b of the lower case 22. Since it is not necessary to secure a work space for moving the portion 200 toward the end plate 12, the battery pack 1 can be fixed to the battery case 2 with the length in the Y direction being further suppressed.

  The positioning mechanism 320 has a first guide surface (concave surface 322b) for allowing the concave portion 322 to contact the convex portion 321 and align the bolt insertion hole 12e with the bolt hole 201 of the fixing portion 200 in the Y direction. Since the concave portion 322 has a second guide surface (concave surface 322c) for making the bolt insertion hole 12e and the bolt hole 201 of the fixing portion 200 coincide with each other in contact with the convex portion 321 in the X direction, In the direction, the bolt hole 201 can be aligned with the bolt insertion hole 12 e, and the assembled battery 10 can be easily assembled to the lower case 22.

  In the positioning mechanism 320 in the above-described fixing structure, a fitting structure in the vertical direction of the end plate 12 in which a concave portion is provided in the fixing portion 200 and a convex portion is provided in the end plate 12 may be employed. Moreover, the shape of the convex part 321 and the recessed part 322 is not limited to a quadrangular pyramid shape, and may be an arbitrary polygonal pyramid shape or a conical shape.

  Next, a method of assembling the assembled battery 10 and the lower case 22 (case 2) according to the present embodiment relating to the positioning mechanism 320 having the second fitting structure will be described. In this assembling method, the end plate 12 is made to correspond to the fixing part 200 and the assembled battery 10 is mounted on the lower case 22 and the upper end surface 12e of the end plate 12 is directed to the fixing part 200 positioned below. A step of inserting the fastening bolt B into the bolt insertion hole 12e and a step of fastening the fastening bolt B inserted through the bolt insertion hole 12e to the fixing portion 200 to fix the end plate 12 to the lower case 22. In the above-described process, when the assembled battery 10 is mounted from above the lower case 22, the fixing portion 200 is fixed to the end plate 12 with respect to the end plate 12 by a fitting structure that fits in the vertical direction of the end plate 12. And a positioning step of aligning the bolt insertion hole 12e and the bolt hole 201 in the Y direction.

  A more specific description will be given with reference to FIG. FIG. 9 is a diagram for explaining a process of assembling the assembled battery 10 to the lower case 22 with a fixing structure including the positioning mechanism 320 having the second fitting structure shown in FIG. 7.

  As shown in FIG. 9, first, the assembled battery 10 is mounted on the lower case 22 together with the end plate 12 on the pedestal 210 on which the fixing portion 200 is disposed (the left diagram in FIG. 9). At this time, the top part 321a of the convex part 321 of the fixed part 200 extends in the Y direction inside the concave part 322 formed on the lower end surface 12d of the end plate 12, in other words, from the top part 322a of the concave part 322 to both sides in the Y direction. Each concave surface 322b is located inside the concave portion 322 facing. In the example of FIG. 9, the top portion 321a of the convex portion 321 is positioned inside the concave portion 322 facing the left concave surface 322b in the Y direction, but the top portion 321a of the convex portion 321 is the right concave surface 322b in the Y direction. The assembled battery 10 can also be mounted on the lower case 22 so as to be located inside the concave portion 322 facing the surface.

  In the assembling method, in the step of mounting the assembled battery 10 on the lower case 22, when the assembled battery 10 is mounted from above the lower case 22, the fixing unit 200 is attached to the end plate 12 by the positioning mechanism 320. And a positioning step of aligning the bolt insertion hole 12e and the bolt hole 201 in the Y direction.

  In the positioning mechanism 220 having the first fitting structure described above, the fixed part 200 is moved in the Y direction toward the end plate 12 after the assembled battery 10 is mounted on the lower case 22. In the method, the step of mounting the assembled battery 10 from above the lower case 22 and the positioning step of aligning the bolt insertion hole 12e and the bolt hole 201 in the Y direction are performed at the same time in the same step. In the process of mounting the assembled battery 10 from above the lower case 22, the operator mounts the assembled battery 10 from above the lower case 22 without being aware of the positioning of the bolt insertion holes 12 e and the bolt holes 201. Only by the positioning mechanism 320, the fixing part 200 moves in the Y direction with respect to the end plate 12, and the bolt insertion hole 12e and the bolt hole 201 can be automatically matched in the Y direction.

  As shown in the central view of FIG. 9, when the lower end surface 12d of the end plate 12 approaches the fixing part 200 from above the fixing part 200 during mounting, the top part 321a of the convex part 321 becomes the concave surface 322b of the concave part 322 ( Abut) contact. The top portion 321a moves outward in the Y direction while contacting the inclined surface of the concave surface 322b of the concave portion 322 when the end plate 12 moves downward from the upper side in the Z direction. In the example of FIG. 9, since the convex part 321 and the concave part 322 are formed in the same quadrangular pyramid fitting structure, the inclined surface 321b and the concave surface 322b are also in contact.

  Then, in a state where the lower end surface 12d of the end plate 12 is in contact with the mounting portion 211, the top portion 321a of the convex portion 321 and the top portion 322a of the concave portion 322 coincide with each other in the Y direction, and the movement of the fixing portion 200 is restricted. . In this state, the bolt insertion hole 12e and the bolt hole 201 are aligned in the Y direction via the positioning mechanism 320 (the right diagram in FIG. 9).

  Thereafter, each of the fastening bolts B is inserted into each of the bolt insertion holes 12e opened on the upper end surface 12c of the end plate 12 toward the fixing portion 200 positioned downward in the Z direction, and the end plate 12 and the fixing portion 200 are fastened. (Right figure of FIG. 9). The end plate 12 (the assembled battery 10) is fixed to the lower case 22 via a pedestal 210 fixed to the lower case 22 by welding or the like.

  Even in the fixing structure including the positioning mechanism 320 having the second fitting structure, the end plate 12 and the fixing part 200 are fastened with the fastening bolt B by forming the convex part 321 and the concave part 322 into a polygonal pyramid shape. It is possible to prevent the fixing portion 200 from rotating in the XY plane due to the fastening bolt B being screwed in.

  In particular, the second fitting structure is an inclined surface in which the convex part 321 is entirely covered with the concave part 322 by fitting the convex part 321 and the concave part 322 in the vertical direction between the end plate 12 and the fixing part 200 to form a polygonal pyramid shape. Further, rotation in the XY plane is prevented by contact of the concave surface. For this reason, compared with the 1st fitting structure, the arrangement | positioning position of the positioning mechanism 320 can be set freely, for example, the positioning mechanism 320 can be provided in areas other than the region between the bolt insertion holes 12e in the X direction.

  In the positioning mechanism 220 having the first fitting structure and the positioning mechanism 320 having the second fitting structure described above, the fitting structures that match the bolt insertion holes 12e and the bolt holes 201 in the Y direction are in close contact with each other. It does not have to be a fitting mode. For example, the concave portion is formed larger than the convex portion, and the bolt insertion hole 12e and the bolt hole 201 may coincide with each other in the Y direction in the Y direction in a state where the top portions of the convex portion and the concave portion are in contact with each other. The recessed part should just be formed in the shape which invites a convex part or a recessed part invites a convex part. A plurality of positioning mechanisms 220 and 320 may be provided for one end plate 12.

  FIG. 10 shows the lower part of the two fixing parts 200 corresponding to the pair of end plates 12 constituting the assembled battery 10 of the present embodiment so that one fixing part 200 can move in the Y direction with respect to the bolt insertion hole 12e. A mode in which the other fixed portion 200A is fixedly disposed at the mounting position of the assembled battery 10 with respect to the lower case 22 (the fixed portion 200A is fixed to the bottom portion 22a of the lower case 22 by welding or the like). Show.

  Among the pair of end plates 12 fixed to the lower case 22, by providing the fixing portion 200 corresponding to at least one end plate 12 so as to be movable in the Y direction (stacking direction), the assembled battery 10 and the lower case 22 The assembled battery 10 can be easily assembled to the lower case 22 while simplifying the fixing structure and allowing variation in the stacking direction length of the assembled battery 10.

  FIG. 11 is a view for explaining a fixing structure between the assembled battery 10 </ b> A in which the auxiliary member 14 is disposed at the central portion in the stacking direction of the assembled battery 10 and the lower case 22.

  The assembled battery 10 shown in FIG. 11 includes an auxiliary member 14 that is disposed between the pair of end plates 12 and is sandwiched between the single cells 11 along with the single cells 11. The auxiliary member 14 has the same size and shape as the end plate 12, and from the lower end surface facing the lower case 22 located below to the upper end surface facing the lower case 22, in other words, the auxiliary member 14. A bolt insertion hole 12e of the fastening bolt B extending from the lower end surface (corresponding to the third surface) that contacts the fixed portion 200 of the fixing bolt 200 toward the upper end surface (corresponding to the fourth surface) opposite to the lower end surface is provided on the end plate 12. It is equipped similarly.

  Two fixing portions 200 corresponding to the pair of end plates 12 are provided in the lower case 22 so as to be movable in the Y direction with respect to the bolt insertion holes 12e, and the fixing portion 200B corresponding to the auxiliary member 14 is welded or the like. And fixedly disposed on the bottom 22a of the lower case 22. The pair of end plates 12 and the auxiliary member 14 are fixed to the lower case 22 via the fixing portions 200 and 200B.

  In the example of FIG. 11, with respect to the assembled battery 10 in which a plurality of unit cells 11 are arranged and stacked, the stacking region of the unit cells 11 between the end plates 12 is fixed to the lower case 22 in addition to the end plate 12 via the auxiliary member 14. Since it did in this way, the assembled battery 10 can be assembled | attached easily, allowing the variation of the lamination direction length of the assembled battery 10 is permitted, suppressing the bending | flexion of the laminated direction of the assembled battery 10. FIG. In addition, the auxiliary member 14 can be arrange | positioned not in the lamination | stacking direction center site | part of the assembled battery 10, but in arbitrary site | parts in view of suppression of a bending.

  Next, a modified example of the end plate 12 of the present embodiment will be described. FIG. 12 is a configuration perspective view of an end plate 120 according to a modification. FIG. 13 is a plan view of the end plate 120. In the following description, the same components as those of the end plate 12 shown in FIG.

  The end plate 120 is used as an end plate disposed at an end portion in the stacking direction of the assembled battery 10 in which the plurality of single cells 11 are arranged in a predetermined direction. The pair of end plates 120 is connected to a restraining member 13 extending in the Y direction, and both ends of the restraining member 13 are fixed to the pair of end plates 120, so that the plurality of single cells 11 constituting the assembled battery 10 are fixed. To give a binding force.

  And the end plate 120 is fastened by the fastening bolt B to the fixing portion 200 provided in the lower case 22 that constitutes the case 2 that houses the assembled battery 10 in the same manner as the end plate 12 shown in FIG. Fixed to the lower case 22.

  As shown in FIG. 12, the end plate 120 is movable in the Y direction with respect to the bolt insertion hole 12e of the fastening bolt B extending from the upper end surface 12c toward the fixing portion 200 positioned below and the bolt insertion hole 12e. And a positioning mechanism 220 (222) for positioning the fixing portion 200 provided at the position where the bolt insertion hole 12e and the bolt hole 201 of the fixing portion 200 coincide with each other in the Y direction.

  The end plate 120 can be divided into three regions in the X direction. The first region R1 located at the X-direction central portion, the second region R2 adjacent to the first region R1, where the columnar rib 121 is formed, and the end portion in the X direction where the connecting portion 12b with the restraining member 13 is formed The third region R3 on the side is included.

  The second region R2 is a region that is spaced apart in the X direction across the first region R1, and columnar ribs 121 extending from the upper end to the lower end of the end plate 120 in the Y direction are formed. Bolt insertion holes 12e are formed in the columnar ribs 121 extending in the vertical direction. The rib 121 includes a predetermined region in which the bolt insertion hole 12e is formed, has a predetermined width in the X direction, and has a predetermined thickness in the Y direction.

  In this modification, two ribs 121 are provided corresponding to the two bolt insertion holes 12e and spaced apart in the X direction of the end plate 120. However, depending on the number of the bolt holes 201 of the fixing portion 200, Three or more ribs 121 may be provided.

  Reinforcing ribs 122 and 123 extending from one rib 121 toward the other rib are provided in the first region R1 between the two ribs 121 spaced apart in the X direction. The reinforcing rib 122 is extended from the upper side in the Y direction of the rib 121 to the lower side, and is provided so that the two reinforcing ribs 122 intersect on the XZ plane. As shown in FIG. 12, the two reinforcing ribs 122 can be integrally formed in an X shape, for example. The reinforcing rib 123 is provided so as to extend substantially parallel to the X direction from one columnar rib 121 toward the other rib 121.

  The reinforcing ribs 122 and 123 of this modification can be provided integrally with the columnar rib 121. For example, with respect to a rectangular end plate having a predetermined thickness in the Y direction, a region other than the reinforcing ribs 122 and 123 in the first region R1 is thinned in the Y direction so as to be integrated with the columnar rib 121. Ribs 122 and 123 can be formed. The reinforcing ribs 122 and 123 are plate-like members having a predetermined thickness in the Z direction, and have a width smaller than the thickness of the end plate 120 in the Y direction. The region to be thinned is formed so as not to penetrate from the outer end surface 12a to the inner end surface 12f, and the bottom of the region to be thinned and the inner end surface 12f have a predetermined thickness in the Y direction.

  Further, the reinforcing rib 123 located on the lower end surface 12d side of the end plate 120 is formed to have a height (thickness) in the Z direction larger than that of the reinforcing rib 123 on the upper end surface 12c side, and the convex portion 221 of the fixing portion 200. A concave portion 222 constituting the positioning mechanism 200 corresponding to the above is provided. The recess 222 can be formed by recessing (cutting out) the end surface 12a of the reinforcing rib 123 (end plate 120) toward the inside.

  Further, the third region R3 of the end plate 120 has the same predetermined thickness as the rib 121 in the Y direction, and is provided with a connecting portion 12b to which the restraining member 13 (fixed portion 13a) is connected. Two connecting portions 12b are provided corresponding to the two restraining members 13 and spaced apart in the vertical direction (Z direction) on the outer end surface 12a. The connecting portion 12b is a bolt hole corresponding to a fastening bolt for fastening the restraining member 13, and penetrates in the Y direction from the outer end surface 12a to the inner end surface 12f. In addition, the connection part 12b can also be formed in the bolt hole which does not penetrate in the Y direction.

  In the third region R3, a lightening portion C is formed in a region between the two connecting portions 12b that are separated in the Z direction. The lightening portion C is a space that does not penetrate from the outer end surface 12a to the inner end surface 12f in the Y direction.

  The inner end surface 12f of the end plate 120 is a surface facing the single cell 11 located at the end of the plurality of single cells 11 stacked in the Y direction. The inner end face 12f is provided with a plurality of ribs 124 protruding in the Y direction. The ribs 124 extend in the X direction, and the ribs 124 are arranged at a predetermined interval in the Y direction. The rib 124 abuts on the end surface of the unit cell 11 in the XZ plane, in other words, the end surface of the unit cell 11 that is substantially parallel to the inner end surface 12f of the end plate 120 in the stacking direction. A flow path for flowing a cooling medium such as air is formed therebetween. In this modification, the protruding ribs 124 extending in the X direction are formed so that a path through which the cooling medium flows is formed on the left and right as viewed in the stacking direction. Protruding ribs 124 extending in the Y direction may be formed so that a path through which the gas flows is formed.

  Further, the inner end surface 12f of the end plate 120 is provided with contact portions 12g that contact the left and right side surfaces in the stacking direction of the unit cells 11 at the end portions in the X direction. The contact portion 12g is formed to extend in the Y direction from the inner end surface 12f toward the side surface of the unit cell 11.

  As described above, the end plate 120 of the present modified example allows the assembled battery 10 to be easily assembled to the lower case 22 while allowing variation in the stacking direction length of the assembled battery 10. It can be used as an end plate that can realize the above.

  The end plate 120 functions as a reinforcing member against the pressure applied by the columnar ribs 121 extending in the vertical direction to the end plate 120 (pressure corresponding to the restraining force applied to the plurality of single cells 11 stacked by the restraining member 13). In addition, the strength of the end plate can be improved. That is, it is possible to improve the strength against the deflection of the end plate 120 in the Y direction with respect to the restraining force that restrains the plurality of unit cells 11 that are stacked.

  Further, since the reinforcing ribs 122 and 123 extending in the X direction are provided in the region between the two ribs 121 where the bolt insertion holes 12e are formed, a binding force that restrains the plurality of unit cells 11 arranged in a stacked manner. On the other hand, the strength against the deflection of the end plate 120 in the X direction can be improved, and the end plate 120 is provided by the columnar rib 121 extending in the vertical direction and the reinforcing ribs 122 and 123 installed in the first region R1 between the ribs 121. The strength in the XZ plane can be improved.

  Further, as compared with the above-described end plate 12, the area other than the bolt insertion hole 12e and the connecting portion 12b is subjected to the lightening process, so that the weight can be reduced while maintaining a predetermined strength.

  In the battery pack 1 of the present embodiment, the fastening bolt B inserted through the end plate 12, the fixing portion 200, and the bolt insertion hole 12e may be made of the same metal material. By comprising in this way, a deformation | transformation of each part can be suppressed by making the thermal expansion characteristic the same.

1: battery pack 10: assembled battery 11: single battery 12: end plate 12a: end face (outer end face)
12c: Upper end surface (second surface)
12d: Lower end surface (first surface)
12e: Bolt insertion hole 13: Restraining member 14: Auxiliary member 2: Battery case 21: Upper case 22: Lower case 200: Fixing part 201: Bolt hole 210: Base 211: Mounting part (contact part)
220: Positioning mechanism 221: Convex part (first positioning part)
222: Concave portion (second positioning portion)
320: Positioning mechanism 321: Convex part (first positioning part)
322: Concave portion (second positioning portion)

Claims (8)

A plurality of power storage elements arranged in a predetermined direction, and a power storage module provided with a pair of end plates sandwiching the plurality of power storage elements in the predetermined direction;
A fixing part for fixing the power storage module to the case, and fixing the end plate and the case with a fastening bolt;
A bolt insertion hole of the fastening bolt formed on the end plate and extending from a first surface in contact with the fixed portion toward a second surface facing the first surface;
The fixing portion corresponding to at least one of the pair of end plates is provided to be movable in the predetermined direction with respect to the bolt insertion hole,
The power storage device further comprising a positioning mechanism that matches the bolt insertion hole and the bolt hole of the fixed portion movable in the predetermined direction in the predetermined direction. The positioning mechanism includes a first positioning portion provided in the fixed portion and a second positioning portion provided in the end plate,
When the power storage module is provided in the case and the fixing portion is moved in the predetermined direction, the first positioning portion and the second positioning portion are arranged in the predetermined direction of the end plate. 2. The power storage device according to claim 1, wherein the power storage device is formed in a fitting structure in which the outer end surfaces are fitted to each other. The fixing portion is provided to be movable in a direction orthogonal to the predetermined direction,
The second positioning portion is in contact with the first positioning portion with respect to the movement of the fixing portion in the predetermined direction, and the bolt insertion hole and the bolt of the fixing portion in a direction orthogonal to the predetermined direction. The power storage device according to claim 2, further comprising a guide surface for matching the hole. The positioning mechanism includes a first positioning portion provided in the fixed portion and a second positioning portion provided in the end plate,
The first positioning part and the second positioning part are formed in a fitting structure that fits together in a direction in which the bolt insertion hole extends,
When the power storage module is provided in the case, the fixing portion is fixed to the end plate by the fitting structure so that the bolt insertion hole and the bolt hole are aligned in the predetermined direction. The power storage device according to claim 1, wherein the power storage device moves in a direction.   The second positioning portion is in contact with the first positioning portion when the power storage module is provided in the case, and matches the bolt insertion hole and the bolt hole of the fixing portion in the predetermined direction. The power storage device according to claim 4, further comprising: a first guide surface.   The second positioning part is in contact with the first positioning part when the power storage module is provided in the case, and the bolt insertion hole and the bolt hole of the fixing part in a direction orthogonal to the predetermined direction. The power storage device according to claim 5, further comprising a second guide surface for matching the two. The case includes a pedestal that is positioned between the case and the first surface of the end plate and on which the fixing portion is disposed.
The pedestal is located between the first surface of the end plate and the fixed portion, and has a contact portion that contacts the first surface of the end plate;
The contact portion is formed with a first opening corresponding to the bolt hole of the fixing portion and a second opening corresponding to the positioning mechanism, and each of the first opening and the second opening is The power storage device according to any one of claims 1 to 6, wherein the power storage device has an elongated hole shape in the predetermined direction. The power storage module is disposed between the pair of end plates, and has an auxiliary member provided so as to be sandwiched between the power storage elements along with the power storage elements,
The auxiliary member has a bolt insertion hole of the fastening bolt extending from a third surface in contact with the fixed portion toward a fourth surface facing the third surface,
The pair of end plates and auxiliary members are fixed to the case via the fixing portions, and the two fixing portions corresponding to the pair of end plates are in the predetermined direction with respect to the bolt insertion holes. 8. The power storage device according to claim 1, wherein the fixing portion corresponding to the auxiliary member is fixedly arranged with respect to the case. .