JP2010108734A - Battery module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a battery module mechanically assembling and integrating a plurality of battery cells with superb reliability in a simple structure. <P>SOLUTION: The battery module is provided with battery cells, and a casing member consisting of wall-like parts each opposed in separation to one of the two widest faces of the battery cell, stepped parts protruded toward a battery cell side from a part of area of the wall-like part each opposed to the battery cell, and round holes extended in a thickness direction of the wall-like parts provided at four corners of each wall-like part overhanging from areas opposed to the battery cell. Vertical cross-section shapes of two diagonally opposed two round holes of the casing member are H-shaped, and those of the rest are rectangular, and further, fastening screws are provided, for coupling adjacent casing members, each going from the vertical cross-section H-shaped round hole of the casing member through to the vertical cross-section rectangular round hole of the adjacently positioned casing member and with a head part fitted inside the vertical cross-section H-shaped round hole. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a battery module having a plurality of battery cells, and more particularly to a battery module in which a plurality of battery cells are assembled via a casing member to have an integrated configuration.

  Battery devices used in vehicles such as HEVs (hybrid electric vehicles) and EVs (electric vehicles) are required to have a relatively high output and cope with frequent output changes. Generally, it is configured as one battery module in which a plurality of battery cells are electrically connected and mechanically integrated according to the required output and capacity. Each battery cell of the battery module is arranged such that an appropriate space is generated between them in consideration of heat dissipation, for example.

  There are the following generally desired conditions for a member for mechanically holding a plurality of battery cells and arranging them to create a space between them. First, it is preferable that the member itself is small, lightweight, and has a simple configuration and does not hinder the heat dissipation of each battery cell. In addition to this, it should be noted that each battery cell may be deformed over time. That is, the internal gas pressure changes over time during use, causing deformation of the outer can. It is necessary to maintain a state of being integrally held against such deformation without impairing reliability.

In addition, there exists a thing disclosed in the following patent document 1 as an example of the battery module of the said use. This disclosure discloses matters similar to the contents of the present application regarding the configuration of a member that mechanically holds a plurality of battery cells integrally. However, it can be seen that there is room for further consideration in terms of ease of assembly, the number of members, and the variable correspondence of the number of battery cells.
Special table 2008-521199 gazette

  The present invention has been made in view of the above circumstances, and in a battery module having a plurality of battery cells, a battery module in which a plurality of battery cells are assembled and integrated with a mechanically reliable and simple configuration. The purpose is to provide.

  In order to solve the above problems, a battery module according to an aspect of the present invention includes a battery cell having a substantially rectangular parallelepiped shape; and one surface of the widest two surfaces of the rectangular parallelepiped shape of the battery cell. A wall-shaped portion facing and spaced apart from each other, a step-shaped portion protruding from the partial region facing the battery cell of the wall-shaped portion toward the battery cell, and the battery cell facing the battery cell at four corners of the wall-shaped portion A casing member having a round hole extending in the thickness direction of the wall-like portion, and extending from a region where the wall-shaped portion extends, and a set of the battery cell and the casing member passes through the casing member one by one. A plurality of the battery cells are provided so as to be stacked, and two round holes at positions opposite to each other of the round holes of the casing member are respectively formed on both ends. The remaining two round holes at opposite positions of the round holes of the casing member have the same diameter and a rectangular cross section. Further, the shape of the casing member is further extended from the round hole having the H-shaped longitudinal section of the casing member to the round hole having the rectangular shape of the longitudinal direction of the casing member positioned next to the casing member, and the head is the longitudinal section. It is characterized by comprising a fastening screw for connecting adjacent casing members, which fit inside the H-shaped round hole.

  That is, this battery module is basically configured by preparing a plurality of sets each including a battery cell and a casing member, and arranging them so that the battery cells are stacked. The casing member has a wall-like portion facing the widest surface of the battery cell, and a stepped shape that projects from the wall-like portion and faces a partial region of the widest surface of the battery cell. There is a department. This stepped portion is for securing a space between the battery cell and the wall-like portion in response to the deformation of the battery cell.

  The casing member is provided with round holes extending from regions facing the battery cells at the four corners of the wall-like portion and extending in the thickness direction of the wall-like portion. As for these round holes, the two round holes facing diagonally are respectively H-shaped as a vertical cross-sectional shape, and the remaining two round holes facing diagonally are each as a vertical cross-sectional shape. It is rectangular. And in order to fix a casing member and the adjacent casing member, it goes out from the round hole of the longitudinal cross-section H shape of a casing member to the round hole of the longitudinal cross-section rectangular shape of the casing member located next to this casing member, The part is provided with a fastening screw that fits inside a round hole having an H-shaped longitudinal section.

  According to such connection and fixing of the casing members, the fixing mode of the two casing members can be applied to a case where a set of a casing member and a battery cell to be provided further outside is added and fixed. . There is no difficulty in alignment and fixing is easier than fixing many sets at once. Since the configuration is simple and the battery cell can be deformed, the reliability is good.

  According to the present invention, it is possible to provide a battery module in which a plurality of battery cells are assembled and integrated with a mechanically reliable and simple configuration.

  As an embodiment of the present invention, each of the casing members may be a plane-symmetric solid having a virtual plane passing through the center of thickness of the wall-shaped portion as a plane of symmetry. According to this, it is not necessary to prepare two types of casing members having different positions of the round holes having the H-shaped vertical cross section.

  Here, each of the casing members has an upright portion that stands up in both directions orthogonal to the wall-like portion from an end portion of the wall-like portion, and the end surface of the upright portion is located adjacent to the casing member. Opposed to the end surface of the upright portion, fixed to each other, and opposed to the stepped portion of the casing member facing the one surface of the battery cell and the other of the widest two surfaces of the battery cell The distance between the stepped portion of the other casing member to be longer than the distance between the widest two surfaces of the battery cell may be set. In this aspect, the space between the battery cell and the adjacent casing member is secured from the wall portion of the adjacent casing member instead of the stepped portion of the adjacent casing member. This is performed by facing the end surfaces of the raised portions.

  Here, the end surface of the upright portion of the casing member may be fixed to each other with an adhesive so as to face the end surface of the upright portion of the adjacent casing member. By using the adhesive in this way in addition to fastening the casing members with screws, it is possible to achieve a stronger and more reliable integration as a battery module.

  As an embodiment, the battery cells and the casing member constituting the set may be fixed by an adhesive at the stepped portion of the casing member. By fixing the casing member and the battery cell with the adhesive in this way, it is possible to achieve a stronger and more reliable integration as a battery module.

  Based on the above, embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a casing member and battery cells for constituting a battery module according to an embodiment of the present invention. As an outline, the battery module of this embodiment is configured by integrally superposing the illustrated casing members 10 and battery cells 20 alternately. Therefore, first, the configurations of the casing member 10 and the battery cell 20 will be described.

  As shown in FIG. 1A, the casing member 10 includes a wall-like portion 11, a step-like portion 12, H-shaped vertical cross-sectional round holes 13, 15, rectangular vertical cross-sectional round holes 14, 16, and a vent hole portion. 17, a slit 18, and a standing part 19. The casing member 10 having such a configuration can be formed by molding using a resin such as polycarbonate resin. Other than the polycarbonate resin, a PPS (polyphenylene sulfide) resin or a PPE (polyphenylene ether) resin may be employed. The rigidity may be increased by appropriately adding a reinforcing material to the resin.

  The wall-shaped part 11 is a wall for separating and facing one of the two widest surfaces of the battery cell 20 when the rectangular battery cell 20 is accommodated in the casing member 10. For this separation, a stepped portion 12 is formed on the wall-like portion 11 so as to protrude from the partial region of the one surface of the battery cell 10. By separating the battery cell 20 and the wall-shaped portion 10, a space is formed between one of the six surfaces of the battery cell 20 and the surface with the greatest deformation over time, improving the reliability of the battery module. Can contribute.

  As described above, the stepped portion 12 is a portion that protrudes from the wall-shaped portion 11 and serves as a spacer to cope with the deformation of the battery cell 20. As shown in the drawing, providing near the end of the wall-like portion 11 is appropriate for efficiently creating a margin space for the battery cell 20 to be deformed. Specifically, the height of the stepped portion 12 can be about 1.5 mm, for example.

  The H-shaped vertical cross-section round holes 13 and 15 and the rectangular vertical cross-section round holes 14 and 16 are positions on a region where the wall-like portion 11 is virtually extended outside the one surface of the battery cell 20. It is provided at each of the neighboring positions from the four corners of this one surface. These round holes 13, 15, 14, 16 are provided in the thickness direction of the wall-shaped portion 11, and are fastening holes for fastening screws (a plurality of casing members 10 and battery cells 20 are stacked and integrated) Used as a fastening screw hole).

  As a more specific positional relationship, H-shaped vertical cross-section round holes 13 and 15 are provided at positions facing the diagonal of the wall-shaped portion 11, and rectangular-shaped vertical cross-sections at the remaining positions facing the diagonal of the wall-shaped portion 11. Round holes 14 and 16 are provided. The effect of these two types of holes having different vertical cross-sectional shapes will be described later (FIGS. 3 and 4). The H-shaped vertical cross-sectional round holes 13 and 15 are holes in which no thread is formed on the inner wall surface, and the rectangular vertical cross-sectional round holes 14 and 16 may be threaded on the inner wall surface. Or a non-threaded hole.

  The vent hole portion 17 is provided corresponding to the position of the gas exhaust surface portion 23 of the battery cell 20 when the battery cell 20 is accommodated in the casing member 10. The vent hole portion 17 communicates with each gas exhaust surface portion 23 when a set composed of the casing member 10 and the battery cell 20 is stacked and stacked to assemble the battery module, and a plurality of sets are walled. It becomes a continuous air hole that penetrates in the direction orthogonal to the shape portion 11.

  The slit 18 is provided in the standing portion 19 so as to communicate with the space between the battery cell 20 formed by the stepped portion 12 and the wall-like portion 11 so as to ensure ventilation for heat dissipation. For example, as shown in the figure, the battery cell 20 after being accommodated can be provided at the left and right positions and the lower position as viewed from the position.

  The upright portion 19 is provided upright from the end of the wall-shaped portion 11 and has a function of position restriction for accommodating the battery cell 20 in the casing member 10. The setting of the height of the upright part 19 from the wall-like part 11 will be described later.

  The casing member 10 can be designed to be a plane-symmetric solid with a virtual plane passing through the thickness center of the wall-shaped portion 11 as a symmetry plane. According to this, it is not necessary to prepare two types of casing members 10 having different positions of round holes having a vertical cross-section H shape, and assemblability is improved (which will be further described later). Hereinafter, unless otherwise specified, the casing member 10 will be described as a plane-symmetric solid.

  Next, as shown in FIG. 1B, the battery cell 20 includes electrodes 21 and 22 and a gas exhaust surface portion 23. The battery cell 20 includes, for example, an aluminum outer can and has a substantially rectangular parallelepiped shape. When the battery cell 20 is housed in the casing member 10, one of the two widest surfaces of the battery cell 20 is the casing member. 10 wall-like parts 11 are made to oppose. The battery cell 20 is a secondary battery such as a lithium ion battery or a nickel metal hydride battery.

  The battery cell 20 includes electrodes 21 and 22 on one of the narrowest surfaces of the rectangular parallelepiped shape. Further, a gas exhaust surface portion 23 is provided at substantially the center of the surface on which the electrodes 21 and 22 of the battery cell 20 are provided. The gas exhaust surface portion 23 has a function of releasing the gas pressure inside the battery cell 20 when the gas pressure in the battery cell 20 rises to some extent during use. As already described, the gas exhaust surface portion 23 is formed through the exhaust hole portion 17 in a state where the battery cell 20 is accommodated in the casing member 10 and the battery module 20 is connected to form a battery module. Facing the space in the pores.

  FIG. 2 is a cross-sectional view illustrating a configuration of a fastening screw hole in the casing member 10 illustrated in FIG. In FIG. 2, the same parts as those shown in FIG. As shown in FIG. 2A, the round holes 13 and 15 have an H-shaped longitudinal cross-sectional shape, that is, a smaller diameter round hole is formed near the center of the thickness, and a larger diameter round hole has a thickness. It is a through hole formed on both ends. The round holes 14 and 16 are through-holes having a rectangular longitudinal cross-sectional shape, that is, a constant diameter. The diameters of the round holes 14 and 16 are set to be slightly smaller than the diameter in the vicinity of the center of the thickness of the round holes 13 and 15 having the H-shaped vertical cross section.

  FIG. 3 is a perspective view showing an aspect in which another casing member is connected to the casing member 10 using the casing member 10 and the battery cell 20 shown in FIG. 1. In FIG. 3, the same reference numerals are given to the same components as those already described in the drawings. Hereinafter, the connection of the casing members will be described with reference to FIG.

  In FIG. 3, the other casing member is indicated by reference numeral 10 </ b> A, and the constituent elements thereof are indicated by adding A to the reference numerals of the corresponding parts of the casing member 10. In this case, the casing member 10 </ b> A is a member having exactly the same configuration as the casing member 10, and their directions are opposite to each other (inverted). As shown in the figure, a round hole 13A (vertical section H shape) of the casing member 10A and a round hole 16 (vertical section rectangular shape) of the casing member 10 are connected by a fastening screw 32, and similarly, the round hole 15A. This is because the fastening screw 31 connects the (vertical longitudinal section H-shaped) and the round hole 14 (vertical sectional rectangular shape).

  Thus, the fastening screws 31 and 32 are used only in the round holes 13A and 15A located at the diagonal of the wall-shaped portion 11A. The round holes 14A and 16A located on the remaining diagonals of the wall-like portion 11A are used for connection with still another casing member positioned on the upper side of the illustrated casing member 10A. In this way, since the fastening screw is used to connect only the casing members located next to each other, there is no difficulty in aligning the casing members and it is easier to assemble than connecting and fixing many casing members at once. It is.

  FIG. 4 is a cross-sectional view showing a portion of a fastening screw hole in the casing members connected as shown in FIG. In FIG. 4, the same reference numerals are given to the same elements as those shown in the already described drawings.

  As shown in FIG. 4, the fastening screw 32 (31) passes through the H-shaped vertical section round hole 13 </ b> A and is screwed into the rectangular vertical section round hole 16. As already described, a thread may be formed in advance on the inner wall surface of the rectangular round hole 16 in the vertical cross section so as to correspond to the fastening screw 32, or as a rectangular round hole 16 in the vertical cross section, Instead of providing a screw thread in advance, the screw thread of the fastening screw 32 may have a diameter that can be received by plastic deformation of the inner wall surface.

  As shown in the drawing, the head of the fastening screw 32 (31) is housed inside a larger diameter portion of the round hole 13A having an H-shaped vertical cross section. This prevents interference from occurring when another casing member is connected to the casing member 10A.

  FIG. 5 is a perspective view showing an aspect in which another battery cell 20A and another casing member 10B are connected using the casing member and the battery cell connected as shown in FIG. In FIG. 5, the same reference numerals are given to the same elements as those shown in the already described drawings. In this case, the casing member 10B is a member having exactly the same configuration as the casing member 10 and the casing member 10A, and their directions are opposite to each other (inverted) with respect to the casing member 10A.

  As a result, as shown in the figure, the round hole with the H-shaped longitudinal section of the casing member 10B and the round hole with the rectangular longitudinal section of the casing member 10A can be connected by the fastening screws 33 and 34. In this manner, more battery cells and casing members can be stacked and integrated. After the integration, one battery module is obtained by connecting the electrodes of each battery cell with a conductive member.

  The battery module having such a configuration can maintain a state in which the battery cells are stably assembled and integrated regardless of the deformation of the battery cells over time. In addition, the battery module has a simple configuration due to the functional group as described above of the casing member. Furthermore, it is easy to vary the number of battery cells according to the number of battery cells required, and there is no difficulty in aligning the casing members as compared to connecting and fixing many casing members at a time. The assembly by is easy.

  As described above, the battery module according to the embodiment of the present invention has been described. First, as the casing member, the position of the round hole with the H-shaped vertical section and the round hole with the rectangular vertical section are not used as a plane-symmetrical solid with the virtual plane passing through the center of thickness of the wall-shaped part as the symmetric plane. You may make it prepare 2 types of things which are located in the position opposite to each other. In this case, you may make it mutually change the height of the upright part 19 from the wall-shaped part 11 in both directions. In the extreme, the standing part on one side can be eliminated. Further, the stepped portion 12 can be formed only on one side of the wall-shaped portion 11.

  Further, even when each casing member is a plane-symmetric solid whose symmetric plane is a virtual plane passing through the center of thickness of the wall-shaped portion, the height of the standing portion is set as follows. Can do. That is, the distance between the stepped portion of the casing member facing the widest surface of the battery cell and the stepped portion of another casing member facing the widest other surface of the battery cell The height of the upright portion is set so as to be longer than the distance between the widest two surfaces. In this case, the upright portions are brought into contact with each other at their end surfaces, and the contact surfaces can be fixed with, for example, an adhesive. By using the adhesive, it is possible to achieve a stronger and more reliable integration as a battery module.

  Further, the battery cell and the casing member may be fixed to each other with an adhesive at the stepped portion of the casing member. By fixing the casing member and the battery cell with the adhesive in this way, a stronger and more reliable integration as a battery module is realized. Such fixing of the battery cell and the casing member with an adhesive may be performed only by one casing member positioned opposite to the battery cell. Alternatively, when their heights are set so that the upright portions do not come into contact with each other at their end faces, the battery cells may be fixed to both casing members facing the battery cells with an adhesive. it can.

  In addition, as an adhesive which fixes the end surfaces of an upright part, in view of the firmness of fixation, a thermosetting adhesive can be used, for example. Moreover, as an adhesive agent that fixes the battery cell and the casing member, for example, a two-component room temperature curing type epoxy resin can be used. The reason why the room temperature curable type is used is that the adhesive is in direct contact with the battery cell, so that it is not very appropriate to use the thermosetting type which may cause high temperature to be transmitted to the battery cell at the time of fixing.

The perspective view which shows the casing member and battery cell for comprising the battery module which concerns on one Embodiment of this invention. Sectional drawing which shows the structure of the fastening screw hole in the casing member shown in Fig.1 (a). The perspective view which shows the aspect which connects another casing member to a casing member using the casing member and battery cell which were shown in FIG. Sectional drawing which shows the part of the fastening screw hole in the casing member connected as shown in FIG. The perspective view which shows the aspect which connects another battery cell and another casing member using the casing member and battery cell which were connected as shown in FIG.

Explanation of symbols

  10, 10A, 10B ... casing member, 11, 11A ... wall-like part, 12, 12A ... stepped part, 13, 13A, 15, 15A ... H-shaped vertical cross-section round hole, 14, 14A, 16, 16A ... rectangular Shape vertical section round hole, 17, 17A ... vent hole portion, 18, 18A ... slit, 19, 19A ... standing portion, 20, 20A ... battery cell, 21 ... electrode, 22 ... electrode, 23 ... gas exhaust surface portion, 31, 32, 33, 34 ... fastening screws.

Claims (5)

A battery cell having a substantially rectangular parallelepiped shape;
A wall-like portion facing away from one of the two widest surfaces of the rectangular parallelepiped shape of the battery cell, and a part of the wall-like portion facing the battery cell from the region facing the battery cell A casing member having a stepped portion protruding into the wall portion, and a round hole extending in a thickness direction of the wall-shaped portion provided to protrude from a region facing the battery cell at four corners of the wall-shaped portion. ,
A plurality of sets of the battery cell and the casing member are provided so that the battery cells are stacked in a stack through the casing members one by one,
Two round holes at positions opposite to the diagonal of the round holes of the casing member each have stepped portions at both ends, and the vertical cross-sectional shape is H-shaped,
The remaining two round holes at positions facing diagonally of the round holes of the casing member are respectively the same diameter over the entire length, and the longitudinal sectional shape is rectangular,
Furthermore, the vertical cross-section of the casing member that passes through the round hole with the H-shaped vertical section of the casing member passes through the round hole with the rectangular cross-section of the casing member positioned next to the casing member, and the head has the H-shaped vertical cross-section A battery module comprising a fastening screw for connecting adjacent casing members, which fit inside a round hole, to each other.   2. The battery module according to claim 1, wherein each of the casing members is a plane-symmetric solid having a virtual plane passing through the center of thickness of the wall-shaped portion as a plane of symmetry. Each of the casing members has an upright portion standing in both directions orthogonal to the wall-shaped portion from an end portion of the wall-shaped portion, and an end surface of the upright portion is adjacent to the upright portion of the casing member positioned next to the wall-shaped portion. Fixed to each other facing the end face,
The stepped portion of the casing member facing the one surface of the battery cell, and the stepped portion of another casing member facing the other of the two widest surfaces of the battery cell; The battery module according to claim 2, wherein the distance is longer than the distance between the widest two surfaces of the battery cell.   4. The battery module according to claim 3, wherein the end surfaces of the upright portions of the casing member are fixed to each other with an adhesive so as to face the end surfaces of the upright portions of the adjacent casing members.   The battery module according to claim 1, wherein the battery cell and the casing member constituting the set are fixed by an adhesive at the stepped portion of the casing member.

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