JP6390721B2 - Battery pack - Google Patents

Description

  One aspect of the present invention relates to a battery pack.

  Patent Document 1 describes an assembled battery (battery module) formed by integrally stacking a plurality of prismatic battery cells. In this assembled battery, a metal restraint plate is abutted against a prismatic battery cell located at an end of the stacked prismatic battery cells. The pair of restraining plates are connected to each other by a long connecting member so that the square battery cell is pressed.

JP 2001-236937 A

  By the way, when a plurality of battery modules are fixed to the battery pack housing, a pair of fixing members are arranged at both ends in the stacking direction of the battery cells for each battery module, and the battery is interposed via the fixing members. The module is fixed to the housing. In addition, when fixing the plurality of battery modules to the housing, it is conceivable to use a pair of fixing members disposed at both ends in a direction intersecting the stacking direction of the battery cells for each battery module. However, in any case, since it is necessary to use a pair of fixing members for each battery module, downsizing of the battery pack is hindered.

  One aspect of the present invention has been made in view of such circumstances, and an object thereof is to provide a battery pack that can be miniaturized.

  In order to solve the above problems, a battery pack according to one aspect of the present invention includes a plurality of battery modules, a housing that houses the battery modules, and a fixing member that fixes the battery modules to the mounting surface of the housing. The battery module includes a stacked body including a plurality of battery cells stacked in a first direction along the mounting surface, and a plurality of cell holders for individually holding each of the battery cells. The cell holder includes a fixing holder used for fixing the battery module, and the fixing holder intersects the first and second side walls extending in the second direction intersecting the mounting surface and the first and second directions. And a first fixing portion projecting from each of the first and second side wall portions in a third direction, and the first and second fixing portions are arranged in the second direction. A through-hole penetrating is provided, and the first and second The side wall portion includes first and second portions arranged along the second direction, and the first fixing portion is provided in the first portion of the first side wall portion, The plurality of battery modules are provided in the second portion of the second side wall portion, and the plurality of battery modules have one through-hole in the first fixing portion in one battery module as viewed from the second direction. The second fixing part in another battery module adjacent to the battery module is arranged so as to overlap with the through hole of the second fixing part, and the fixing member is fastened to the through holes of the first and second fixing parts overlapping each other. By inserting the member, one battery module and another battery module are fixed together on the mounting surface.

  In this battery pack, each of the battery modules includes battery cells stacked on each other and a plurality of cell holders that individually hold the battery cells. The plurality of cell holders include a fixing holder used for fixing the battery module. The fixing holder includes a pair of side wall portions and a pair of fixing portions that protrude from each of the side wall portions and are provided with through holes. And one battery module and another battery module adjacent to the one battery module are arranged so that the fixing portions and the through holes of the fixing holders overlap each other. For this reason, two battery modules adjacent to each other can be collectively fixed to the housing by a single fixing member by inserting the fastening member through the overlapping through holes. That is, the fixing member can be shared by the two battery modules. Therefore, compared with the case where a pair of fixing member is used for each battery module, the size can be reduced.

  In the battery pack according to one aspect of the present invention, in each of the battery modules, the plurality of cell holders may include two or more fixing holders. As described above, when a plurality of fixing holders capable of sharing a fixing member as described above are used for fixing one battery module, the battery module can be stably fixed to the housing while achieving downsizing. Can do.

  In the battery pack according to one aspect of the present invention, the through hole may be a long hole extending along the first direction. In this case, in the state where the fastening member is inserted into the through hole of the fixed holder and the battery module is fixed to the housing, for example, when force is applied to each battery cell by expansion of the battery cell, the extension length of the through hole Therefore, the displacement of each battery cell and each cell holder can be allowed. For this reason, breakage of the fixing member can be suppressed.

  In the battery pack according to one aspect of the present invention, the housing has a bracket protruding from the mounting surface, and the plurality of battery modules are arranged along the third direction to form an array. The end module, which is a battery module located at one end of the array body in the third direction, is arranged so that the first fixing portion and the bracket overlap when viewed from the second direction, and the fixing member is The end module may be fixed to the mounting surface by inserting a fastening member through the through hole and the bracket of the first fixing portion. In this case, the battery module at one end of the array can be stably fixed.

  In the battery pack according to one aspect of the present invention, the battery module is restrained by the restraining member that applies a restraining load to the battery cell along the first direction and the restraining member along with the battery cell along the first direction. And an elastic member. In this case, the displacement of the battery cell is reliably permitted by the cooperation of the elastic member and the through hole which is a long hole. As a result, the fixing member can be reliably prevented from being damaged.

  According to one aspect of the present invention, a battery pack that can be miniaturized can be provided.

It is a partial perspective view of the battery pack according to the present embodiment. FIG. 2 is a side view of the battery pack shown in FIG. 1. FIG. 3 is a perspective view showing a battery cell and a cell holder shown in FIG. 2. It is typical sectional drawing which shows the battery cell and cell holder which were shown by FIG. It is sectional drawing of the battery pack shown by FIG. It is sectional drawing which shows the modification of the cell holder shown by FIG. It is a side view which shows the modification of the battery module shown by FIG.

  Hereinafter, a battery pack according to an aspect of the present invention will be described in detail with reference to the drawings. In the description of the drawings, the same elements or corresponding elements may be denoted by the same reference numerals, and overlapping descriptions may be omitted. In the following drawings, an orthogonal coordinate system S is shown for easy understanding.

  FIG. 1 is a partial perspective view of the battery pack according to the present embodiment. FIG. 2 is a side view of the battery pack shown in FIG. FIG. 3 is a perspective view showing the battery cell and the cell holder shown in FIG. FIG. 4 is a schematic cross-sectional view showing the battery cell and the cell holder shown in FIG. As shown in FIGS. 1 to 4, the battery pack 100 includes a plurality (two by way of example) of battery modules 1, a casing 2 that houses the battery modules 1, and a mounting surface 2 s of the casing 2 of the battery modules 1. And a fixing member 3 for fixing to. The housing 2 has, for example, a box shape, and the mounting surface 2s is the inner surface of the box-shaped housing 2.

  The battery modules 1 are arranged along a third direction (Y-axis direction of the orthogonal coordinate system S) along the mounting surface 2s, and constitute an array A. Each battery module 1 includes a stacked body 20 including a plurality of (here, nine) battery cells 10 stacked along a first direction (X-axis direction in the orthogonal coordinate system S) along the mounting surface 2s. The battery cell 10 includes a plurality of (here, nine) cell holders 30 that individually hold the battery cells 10 and a restraining member 40 that applies a restraining load to the battery cells 10 along the stacking direction of the battery cells 10.

  The battery cell 10 is a nonaqueous electrolyte secondary battery such as a lithium-in secondary battery. The battery cell 10 is electrically connected to an electrode assembly (not shown), a case 11 that accommodates the electrode assembly, and electrodes (each of a positive electrode and a negative electrode) of the electrode assembly and protrudes from the case 11. And a terminal 12. The electrode assembly includes a plurality of positive and negative electrodes, and a separator disposed between the positive and negative electrodes. The positive electrode and the negative electrode are alternately stacked via separators. The stacking direction of the positive electrode and the negative electrode in the electrode assembly matches the stacking direction of the battery cells 10 in the stacked body 20.

  The case 11 has a rectangular parallelepiped shape. The case 11 includes a pair of side surfaces 11a and 11b facing each other, a pair of side surfaces 11c and 11d facing each other, and an upper surface 11e and a bottom surface 11f facing each other. The side surfaces 11a and 11b are surfaces intersecting the electrode stacking direction in the electrode assembly. The side surfaces 11c and 11d are surfaces along the electrode stacking direction in the electrode assembly, and are surfaces that connect the side surface 11a and the side surface 11b. The terminal 12 protrudes from the upper surface 11e. Here, as an example, the bottom surface 11 f is a surface that faces the mounting surface 2 s when the battery module 1 is fixed to the housing 2.

  The cell holder 30 includes a fixing holder used for fixing the battery module 1. Here, as an example, all the cell holders 30 are configured in the same manner. Therefore, all the cell holders 30 can be used for fixing the battery module 1 here. The cell holder (fixed holder) 30 includes a sidewall portion (first sidewall portion) 30c and a sidewall portion (second sidewall portion) 30d that face each other. The cell holder 30 includes an upper wall portion 30e and a bottom wall portion 30f that face each other. In the cell holder 30, a rectangular parallelepiped space portion into which the battery cell 10 is fitted is defined by the side wall portions 30 c and 30 d, the upper wall portion 30 e, and the bottom wall portion 30 f.

  The side wall portions 30c and 30d are disposed on the side surfaces 11c and 11d of the case 11, respectively. The upper wall portion 30e and the bottom wall portion 30f are disposed on the upper surface 11e and the bottom surface 11f of the case 11, respectively. The upper wall portion 30e and the bottom wall portion 30f are provided with through holes 30h through which bolts 43 of a restraining member 40 described later are inserted. The side wall portions 30c and 30d have a long plate shape extending in a second direction (the Z-axis direction of the orthogonal coordinate system S) intersecting the mounting surface 2s.

  The cell holder 30 includes a fixed portion (first fixed portion) 31 protruding outward from the side wall portion 30c in the third direction (the arrangement direction of the battery modules 1), and a side wall portion 30d in the third direction. And a fixing portion (second fixing portion) 32 protruding outward. Here, the fixing portions 31 and 32 have a long rectangular parallelepiped shape extending in the second direction. The fixing portions 31 and 32 are provided with through holes 33 penetrating in the second direction. The through hole 33 is a long hole extending along the first direction (the stacking direction of the battery cells 10) when viewed from the second direction.

  Here, the side wall portions 30c and 30d include a first portion P1 and a second portion P2 arranged along the second direction (see particularly FIG. 4). The fixing portion 31 is provided in the first portion P1 of the side wall portion 30c. The fixing portion 32 is provided in the second portion P2 of the side wall portion 30d. Here, the fixed part 31 and the fixed part 32 do not overlap each other when viewed from the third direction.

  The restraining member 40 includes a pair of end plates 41 disposed at one end 20a and the other end 20b of the stacked body 20 in the first direction, and a fastening member 42 that fastens the end plates 41 to each other (see FIG. 2). ). The restraint member 40 applies a restraint load to the battery cell 10 along the first direction by fastening the end plates 41 to each other using the fastening member 42.

  The fastening member 42 includes, for example, a long bolt 43 and a nut 44 that is screwed to the bolt 43. The bolt 43 is inserted into the end plate 41 at the outer edge portion of the end plate 41, for example, and is inserted into the through hole 30h of the cell holder 30 described above. Then, the nuts 44 are screwed into both ends of each bolt 43 from the outside of the end plate 41, whereby the battery cell 10 and the cell holder 30 are sandwiched and unitized, and a restraining load is applied to the battery cell 10. Is added. Thereby, the battery module 1 is comprised.

  As shown in FIG. 5, the battery module 1 configured as described above is fixed to the mounting surface 2 s of the housing 2 by the fixing member 3. Specifically, when viewed from the second direction, the plurality of battery modules 1 includes a through hole 33 of the fixing portion 31 in the battery module 1A (battery module 1) and a battery module 1B (battery module 1 adjacent to the battery module 1A). ) Is arranged so as to overlap with the through-hole 33 of the fixing portion 32 in FIG. That is, here, the battery module 1 is arranged so that the fixing portion 31 of the battery module 1A and the fixing portion 32 of the battery module 1B are fitted to each other.

  In that state, the fixing member 3 fixes the battery module 1 </ b> A and the battery module 1 </ b> B together on the mounting surface 2 s by inserting the fastening member 60 into the fixing hole 31 and the through hole 33 of the fixing part 32 that overlap each other. To do. The fastening member 60 is, for example, a long bolt, and is screwed into a screw hole provided in the mounting surface 2 s of the housing 2 through the through hole 33 of the fixing portions 31 and 32.

  Here, as shown in FIG. 2, among all the cell holders 30, a pair of cell holders 30 that hold each of the battery cells 10 positioned at both ends of the stacked body 20 in the first direction, and in the first direction A cell holder 30 that holds the battery cell 10 positioned at the center of the stacked body 20 is used to fix the battery module 1.

  The housing 2 has a bracket 50 protruding from the mounting surface 2s. The battery module (end module) 1B located at one end of the array A in the third direction is arranged such that the fixing portion 31 and the bracket 50 overlap each other when viewed from the second direction. That is, the battery module 1 </ b> B is arranged so that the fixing portion 31 is positioned on the bracket 50. In that state, the fixing member 3 further fixes the battery module 1B to the mounting surface 2s by inserting the fastening member 60 through the through hole 33 and the bracket 50 of the fixing portion 31 of the battery module 1B.

  On the other hand, the battery module 1A positioned at the other end of the array A in the third direction is further fixed to the mounting surface 2s by the fastening member 60 inserted through the through hole 33 of the fixing portion 32. Thus, in the battery pack 100, between the battery modules 1A and 1B adjacent to each other along the third direction, the fixing portions 31 and 32 are overlapped with each other and the fixing member 3 is shared.

  As described above, in the battery pack 100 according to the present embodiment, each of the battery modules 1 includes the battery cells 10 stacked on each other and the plurality of cell holders 30 that individually hold the battery cells 10. Have. The plurality of cell holders 30 include a fixing holder used for fixing the battery module 1. The fixing holder includes a pair of side wall portions 30c and 30d and a pair of fixing portions 31 and 32 provided with a through hole 33 projecting from the side wall portions 30c and 30d.

  And one battery module 1A and another battery module 1B adjacent to one battery module 1A are arranged so that the fixing portions 31 and 32 and the through-holes 33 of the fixing holders overlap each other. For this reason, by inserting the fastening member 60 into the overlapping through-hole 33, the two battery modules 1A and 1B adjacent to each other can be collectively fixed to the housing 2 by the single fixing member 3 ( Can be fastened together) That is, the fixing member 3 can be shared by the two battery modules 1A and 1B. Therefore, compared with the case where a pair of fixing allowances and fixing members are used for each of the battery modules 1, the size can be reduced.

  Further, in the battery pack 100 according to the present embodiment, the through holes 33 of the fixing portions 31 and 32 are long holes extending along the first direction. For this reason, in the state which inserted the fastening member 60 in the through-hole 33 of the fixing | fixed part 31 and 32 and fixed the battery module 1 to the housing | casing 2, force was applied to each battery cell 10 by expansion of the battery cell 10, for example. Sometimes, the displacement of each battery cell 10 and each cell holder 30 can be allowed by the extension length of the through hole 33. For this reason, breakage of the fixing member 3 can be suppressed.

  Furthermore, in the battery pack 100 according to the present embodiment, the housing 2 includes a bracket 50 that protrudes from the mounting surface 2s. In addition, the battery module 1B positioned at one end of the array A in the third direction is arranged so that the fixing portion 31 and the bracket 50 overlap with each other when viewed from the second direction. Then, the fixing member 3 fixes the battery module 1B to the mounting surface 2s by inserting the fastening member 60 through the through hole 33 and the bracket 50 of the fixing portion 31. For this reason, the battery module 1B at one end of the array A can be fixed stably.

  The above embodiments describe one embodiment of the battery pack according to one aspect of the present invention. Therefore, the battery pack according to one aspect of the present invention is not limited to the battery pack 100 described above. The battery pack according to one aspect of the present invention can arbitrarily change the above-described battery pack 100 without departing from the scope of the claims.

  For example, as shown in FIG. 6, the battery pack 100 can include a cell holder 30 </ b> A as a fixed holder instead of the cell holder 30 as a fixed holder. In the cell holder 30A, the side wall portions 30c and 30d include a first portion P1, a second portion P2, and a third portion P3 arranged along the second direction. And in the cell holder 30A, the fixing | fixed part 31 is provided in two parts, the 1st part P1 and the 3rd part P3 of the side wall part 30c, and the fixing | fixed part 32 is the 2nd part of the side wall part 30d. It is provided only in the portion P2.

  Also in this case, the fixed part 31 and the fixed part 32 do not overlap when viewed from the third direction. Therefore, also in this case, if the battery modules 1A and 1B are arranged so that the fixing part 32 of the battery module 1B is fitted between the pair of fixing parts 31 of the battery module 1A, the penetration of the fixing part 31 of the battery module 1A is penetrated. The hole 33 and the through hole 33 of the fixing part 32 of the battery module 1B can overlap each other. Therefore, the fixing member 3 can fix the battery modules 1 </ b> A and 1 </ b> B collectively to the mounting surface 2 s of the housing 2 by inserting the fastening member 60 into the overlapping through-hole 33. As described above, in the battery pack 100, the cell holder as a fixed holder only needs to have fixed portions 31 and 32 having arbitrary shapes that can be fitted to each other and overlap the through hole 33.

  Further, in the battery pack 100, it is not necessary to configure all the cell holders 30 in the same shape. In other words, it is not necessary to configure all the cell holders 30 so as to be usable for fixing the battery cells 10 (it is not necessary to use fixed holders). For example, in the above embodiment, among all the cell holders 30, a pair of cell holders 30 positioned at both ends of the stacked body 20 in the first direction, and a cell holder 30 positioned in the center of the stacked body 20 in the first direction Is used for fixing the battery module 1. Therefore, in this case, only those three cell holders 30 may have a structure having the fixing portions 31 and 32 as fixing holders.

  Further, depending on the number of stacked battery cells 10, it may be sufficient to use two cell holders 30 as fixed holders. Therefore, in the battery pack 100, the plurality of cell holders 30 can include two or more fixed holders. Further, the position of the fixed holder is not limited to both ends and the center of the laminate 20.

  Here, as shown in FIG. 7, each battery module 1 may further include an elastic member 80 and a middle plate 81. Here, the elastic member 80 is disposed between the other end 20 b of the stacked body 20 and the end plate 41. In other words, the elastic member 80 is laminated along with the battery cell 10 along the first direction. The middle plate 81 is disposed between the elastic member 80 and the stacked body 20. The elastic member 80 and the middle plate 81 are restrained by the restraining member 40 along the first direction together with the battery cell 10, and a restraining load is applied.

  On the other hand, as described above, the through holes 33 provided in the fixing portions 31 and 32 of the cell holder 30 and through which the fastening members 60 such as bolts are inserted are elongated holes extending in the first direction. Therefore, when the battery cell 10 expands, the elastic member 80 is compressed in the first direction, and the fastening member 60 is relatively moved in the through hole 33, and the displacement of the battery cell 10 is allowed. That is, the displacement of the battery cell 10 is reliably permitted by the cooperation of the elastic member 80 and the through hole 33 which is a long hole. As a result, damage to the fixing member 3 is reliably suppressed. The relative movement of the fastening member 60 in the through hole 33 means that the cell holder 30 that holds the battery cell 10 moves relative to the fastening member 60 that is inserted into the through hole 33 and fixed to the housing 2. As a result, the position of the fastening member 60 in the through hole 33 varies.

  The arrangement and the number of the elastic members 80 are not limited to the example in FIG. For example, the elastic member 80 may be disposed between the battery cells 10 adjacent to each other. Moreover, you may arrange | position the elastic member 80 in each between several pairs of battery cells 10 adjacent to each other. Further, the elastic member 80 may be disposed between the battery cells 10 adjacent to each other and between the battery cell 10 (laminated body 20) and the end plate 41.

  A battery pack that can be miniaturized can be provided.

  DESCRIPTION OF SYMBOLS 1 ... Battery module, 1A ... Battery module (one battery module), 1B ... Battery module (another battery module), 2 ... Housing | casing, 2s ... Mounting surface, 3 ... Fixing member, 10 ... Battery cell, 20 ... Lamination | stacking 30 ... cell holder, 30c ... side wall (first side wall), 30d ... side wall (second side wall), 31 ... fixed part (first fixed part), 32 ... fixed part (second Fixed part), 33 ... through hole, 40 ... restraining member, 50 ... bracket, 60 ... fastening member, 80 ... elastic member, 100 ... battery pack, P1 ... first part, P2 ... second part.

Claims (5)

A plurality of battery modules;
A housing for housing the battery module;
A fixing member for fixing the battery module to the mounting surface of the housing,
The battery module includes a stacked body including a plurality of battery cells stacked in a first direction along the mounting surface, and a plurality of cell holders that individually hold the battery cells,
The plurality of cell holders include a fixing holder used for fixing the battery module,
The fixing holder includes first and second side wall portions extending in a second direction intersecting the mounting surface, and the first and second side walls in a third direction intersecting the first and second directions. First and second fixing portions projecting from each of the side wall portions,
The first and second fixing portions are provided with through holes penetrating in the second direction,
The first and second sidewall portions include first and second portions arranged along the second direction,
The first fixing portion is provided in the first portion of the first side wall portion,
The second fixing portion is provided in the second portion of the second side wall portion,
When viewed from the second direction, the plurality of battery modules include the through hole of the first fixing portion in one battery module and the second in another battery module adjacent to the one battery module. It is arranged so that the through hole of the fixed part of
The fixing member inserts a fastening member into the through holes of the first and second fixing portions that overlap each other, and further fixes the inserted fastening member to the mounting surface, thereby the one battery module. And the other battery module are collectively fixed to the mounting surface by the fastening member ,
Battery pack. In each of the battery modules, the plurality of cell holders include two or more fixed holders,
The battery pack according to claim 1. The through hole is a long hole extending along the first direction.
The battery pack according to claim 1 or 2. The housing has a bracket protruding from the mounting surface,
The plurality of battery modules are arranged along the third direction to form an array.
The end module, which is the battery module located at one end of the array in the third direction, is arranged so that the first fixing portion and the bracket overlap when viewed from the second direction. And
The fixing member fixes the end module to the mounting surface by inserting a fastening member through the through hole of the first fixing portion and the bracket.
The battery pack according to any one of claims 1 to 3. The battery module includes: a restraining member that applies a restraining load to the battery cell along the first direction; and an elastic member restrained by the restraining member along with the battery cell along the first direction. Have
The battery pack according to claim 3.

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