JP2017084466A - Battery pack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery pack capable of preventing movement of an electric cell by suppressing deformation of an exterior member.SOLUTION: An electric cell 110 of a battery pack 100 comprises a battery body 110H including a power generating element 111, and an exterior member (laminate film) for sealing the battery body. A second spacer 122 of the battery pack comprises a plurality of coupling pins 122i for engaging the laminate film. A first extension part 112f of the laminate film extends from a first edge side 110p of the battery body along a direction crossing a lamination direction Z. A second extension part 112g of the laminate film adjoins the first edge side 110p, extends outward along the direction crossing the lamination direction Z from the second edge part 110q of the battery body located closer to the power generating element side than the first edge side longer than the first extension part, and faces a corner of the electric cell, and includes a plurality of coupling holes 112e engaging so as to correspond to each coupling pin. One of the plurality of coupling holes is joined to the corresponding coupling pin 122ii.SELECTED DRAWING: Figure 7

Description

  The present invention relates to an assembled battery in which a plurality of unit cells are stacked.

  The assembled battery is formed by laminating a plurality of unit cells including a power generation element inside the exterior member in the stacking direction. In such an assembled battery, it is necessary to fix the stacked unit cells so that they do not move. In relation to this, for example, Patent Document 1 below discloses a configuration in which a hole is formed in an exterior member, and a plurality of single cells are fixed by a support post that passes through the hole. In Patent Document 1, a laminate exterior material that is easily deformed is used as the exterior member.

JP 2014-78498 A

  However, in the configuration described in Patent Document 1, since only the exterior member is fixed by the support, the exterior member may be easily deformed by vibration or impact. In the assembled battery, when the exterior member is deformed and interferes with surrounding constituent members, a malfunction occurs, and there is a possibility that the expected performance cannot be exhibited.

  The objective of this invention is providing the assembled battery which can suppress a deformation | transformation of an exterior member and can prevent a movement of a cell.

  In order to achieve the above object, an assembled battery of the present invention includes a unit cell and a spacer. The unit cell includes a battery body that includes a power generation element and is formed flat, an exterior member that seals the battery body, and an electrode tab that is led out of the exterior member from the battery body. The spacer is disposed between the stacked unit cells and includes a plurality of engaging portions that engage the exterior member. The exterior member has a first extension part and a second extension part. The first extending portion extends outward from the first edge of the battery body along a direction intersecting the stacking direction. The second extending portion is adjacent to the first edge, and extends along the direction intersecting the stacking direction from the second edge of the battery body located on the power generation element side with respect to the first edge. A plurality of engaged portions are provided that extend outward longer than the existing portions, face the corners of the unit cell, and engage with each of the engaging portions. Here, at least one of the plurality of engaged portions is joined to the corresponding engaging portion.

  According to the assembled battery configured as described above, at least one of the plurality of engaged portions provided in the second extending portion of the exterior member is joined to the engaging portion of the spacer. If it does in this way, in the exterior member, the 2nd extension part prolonged from the edge of a battery main body rather than the 1st extension part, and is easy to change rather than the 1st extension part can be fixed to a spacer. it can. Therefore, the assembled battery can suppress the deformation of the exterior member and prevent the unit cell from moving.

It is a perspective view which shows the assembled battery which concerns on embodiment. It is a perspective view which shows the state which exposed the whole laminated body of the state which decomposed | disassembled the upper pressure plate, the lower pressure plate, and the left and right side plates from the assembled battery shown in FIG. It is a perspective view which removes a protective cover from the laminated body shown by FIG. 2, and decomposes | disassembles a laminated body into a battery group and a bus bar unit. It is a perspective view which decomposes | disassembles and shows the bus bar unit shown by FIG. The state of joining the anode side electrode tabs of the first cell sub-assemblies (single cells connected in parallel every three sets) and the cathode side electrode tabs of the second cell sub-assies (unit cells connected in parallel every three sets) with a bus bar is schematically disassembled. It is a perspective view shown. 6A is a perspective view showing a state in which a pair of spacers (first spacer and second spacer) is attached to a single cell, and FIG. 6B is a pair of spacers (first spacer and first spacer). It is a perspective view which shows the state before attaching 2 spacers. 7A is a perspective view showing a main part in a state where the second spacer is attached to the unit cell, FIG. 7B is a top view showing FIG. 7A from above, and FIG. FIG. 8 is a side view showing a cross section along line 7 (C) -7 (C) in FIG. 7 (B). It is a perspective view which shows a pair of spacer (1st spacer and 2nd spacer). FIG. 9A is a perspective view showing a cross section of the main part in a state where the bus bar is joined to the electrode tab of the stacked unit cell, and FIG. 9B is a side view showing FIG. 9A from the side. is there.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. The size and ratio of each member in the drawings are exaggerated for convenience of explanation and may be different from the actual size and ratio. In the figure, the azimuth is shown using arrows represented by X, Y, and Z. The direction of the arrow represented by X indicates a direction that intersects the stacking direction of the unit cells 110 and is along the longitudinal direction of the unit cells 110. The direction of the arrow represented by Y indicates a direction that intersects the stacking direction of the unit cells 110 and is along the short direction of the unit cells 110. The direction of the arrow represented by Z indicates the stacking direction of the unit cells 110.

  An assembled battery 100 according to an embodiment will be described with reference to FIGS.

  FIG. 1 is a perspective view showing an assembled battery 100 according to the embodiment. FIG. 2 shows a state in which the entire pressurization plate 151, lower pressurization plate 152, and left and right side plates 153 are disassembled from the assembled battery 100 shown in FIG. It is a perspective view. FIG. 3 is a perspective view in which the protective cover 140 is removed from the laminated body 100S shown in FIG. 2 and the laminated body 100S is disassembled into the battery group 100G and the bus bar unit 130. 4 is an exploded perspective view showing the bus bar unit 130 shown in FIG. FIG. 5 shows the anode side electrode tab 113A of the first cell sub-assembly 100M (unit cells 110 connected in parallel every three sets) and the cathode side electrode tab 113K of the second cell sub-assembly 100N (unit cells 110 connected in parallel every three sets). It is a perspective view which decomposes | disassembles and shows the state joined by the bus bar 131 typically. 6A is a perspective view showing a state where a pair of spacers 120 (first spacer 121 and second spacer 122) are attached to the unit cell 110, and FIG. 6B is a pair of spacers 120 attached to the unit cell 110. FIG. It is a perspective view which shows the state before attaching (the 1st spacer 121 and the 2nd spacer 122). 7A is a perspective view showing a main part in a state where the second spacer 122 is attached to the unit cell 110, FIG. 7B is a top view showing FIG. 7A from above, and FIG. ) Is a side view showing a cross section along line 7 (C) -7 (C) in FIG. 7B. FIG. 8 is a perspective view showing a pair of spacers 120 (first spacer 121 and second spacer 122). FIG. 9A is a perspective view showing a cross-sectional view of the main part in a state where the bus bar 131 is joined to the electrode tab 113 of the stacked unit cell 110, and FIG. 9B shows FIG. 9A from the side. It is a side view.

  In the state shown in FIG. 1, the left front side is referred to as the entire assembled battery 100 and the “front side” of each component, and the right rear side is referred to as the entire assembled battery 100 and the “rear side” of each component. The right front side and the left hand back side are referred to as the left and right “side sides” of the entire assembled battery 100 and each component.

  As shown in FIGS. 1 and 2, the assembled battery 100 includes a stacked body 100S including a battery group 100G in which a plurality of flat unit cells 110 are stacked in the thickness direction. The assembled battery 100 further includes a protective cover 140 that is attached to the front surface side of the stacked body 100S, and a housing 150 that houses the stacked body 100S in a state where each of the single cells 110 is pressurized along the stacking direction of the single cells 110. Have. As illustrated in FIG. 3, the stacked body 100 </ b> S includes a battery group 100 </ b> G and a bus bar unit 130 that is attached to the front side of the battery group 100 </ b> G and integrally holds a plurality of bus bars 131. The protective cover 140 covers and protects the bus bar unit 130. As shown in FIG. 4, the bus bar unit 130 includes a plurality of bus bars 131 and a bus bar holder 132 that integrally attaches the plurality of bus bars 131 in a matrix. Among the plurality of bus bars 131, an anode side terminal 133 is attached to the end on the anode side, and a cathode side terminal 134 is attached to the end on the cathode side.

  In summary, the assembled battery 100 of the embodiment includes a single battery 110 and a spacer (second spacer 122). The unit cell 110 includes a battery body 110H that includes a power generation element 111 and is formed flat, an exterior member (laminate film 112) that seals the battery body 110H, and an electrode tab 113 that is led out of the laminate film 112 from the battery body 110H. And provided. The second spacer 122 was disposed between the stacked unit cells 110 and provided with a plurality of engaging portions (connecting pins 122i) for engaging the laminate film 112. The laminate film 112 has a first extending part 112f and a second extending part 112g. The first extending portion 112f extends outward from the first edge 110p of the battery body 110H along the direction intersecting the stacking direction Z (longitudinal direction X or short direction Y). The second extending portion 112g is adjacent to the first edge 110p and intersects the stacking direction Z from the second edge 110q of the battery body 110H located on the power generation element 111 side with respect to the first edge 110p (longitudinal direction X or A plurality of engaged portions that extend outward longer than the first extending portion 112f along the short direction Y), face the corners of the unit cell 110, and engage with each connecting pin 122i. Part (connecting hole part 112e). Here, at least one of the plurality of connecting hole portions 112e is joined to the corresponding engaging portion (the connecting pin 122ii). Hereinafter, the assembled battery 100 of the embodiment will be described in detail.

  As shown in FIG. 5, the battery group 100G includes a first cell sub-assembly 100M composed of three unit cells 110 electrically connected in parallel and a second cell sub-assembly 100N composed of three other unit cells 110 electrically connected in parallel. Are connected in series by a bus bar 131.

  The first cell sub-assembly 100M and the second cell sub-assembly 100N have the same configuration except for the refractive direction of the tip 113d of the electrode tab 113 of the unit cell 110. Specifically, the second cell sub-assembly 100N is obtained by reversing the top and bottom of the unit cell 110 included in the first cell sub-assembly 100M. However, the refraction direction of the tip portion 113d of the electrode tab 113 of the second cell sub-assembly 100N is aligned with the lower side of the stacking direction Z so as to be the same as the refraction direction of the tip portion 113d of the electrode tab 113 of the first cell sub-assembly 100M. ing. Each unit cell 110 has a pair of spacers 120 (first spacer 121 and second spacer 122) attached thereto.

  The unit cell 110 corresponds to, for example, a flat lithium ion secondary battery. As shown in FIGS. 6 and 9, the unit cell 110 includes a battery body 110 </ b> H in which the power generation element 111 is sealed with a pair of laminate films 112, and is electrically connected to the power generation element 111 and led out from the battery body 110 </ b> H. And a thin plate-like electrode tab 113.

  The power generation element 111 is configured by stacking a plurality of positive electrodes 111a and negative electrodes 111b sandwiched between separators 111c. The power generation element 111 is supplied with electric power from the outside and charged, and then supplies electric power while discharging to an external electric device.

  As shown in FIG. 7B, the power generation element 111 partially protrudes from between the positive electrode 111a and the negative electrode 111b while being disposed between the positive electrode 111a, the negative electrode 111b, and the positive electrode 111a and the negative electrode 111b. And a separator 111c provided with a protruding portion 111d. In order to prevent displacement between the positive electrode 111a and the negative electrode 111b, the protruding portions 111d of the separator 111c are fixed with a laminate film 112 interposed therebetween. As shown in FIGS. 6 and 7, the fixed portion is illustrated as three welded portions 111 e that are separated from each other in the region of the protruding portion 111 d.

  The laminate film 112 is configured to cover both sides of the metal foil with an insulating sheet. The pair of laminate films 112 cover the power generation element 111 from both sides along the stacking direction Z and seal the four sides. As shown in FIG. 6, the pair of laminate films 112 lead out the anode-side electrode tab 113 </ b> A and the cathode-side electrode tab 113 </ b> K from between the one end 112 a along the short direction Y to the outside.

  As shown in FIGS. 6 to 8, the laminate film 112 has a pair of connection pins 121 i of the first spacer 121 in a pair of connection holes 112 e provided at both ends of the one end 112 a along the short direction Y. Each is inserted. The laminate film 112 is formed by bending both end portions 112c and 112d along the longitudinal direction X upward in the stacking direction Z.

  As shown in FIGS. 6 and 7, the laminate film 112 has the second extending portion 112g adjacent to both sides of the first extending portion 112f along the short direction Y on the other end portion 112b side. It is composed. As shown in FIG. 7B, the first extending portion 112f is formed to extend outward along the longitudinal direction X from the first edge 110p of the battery body 110H. The first edge 110 p is located along the tip of the protrusion 111 d of the separator 111 c included in the power generation element 111.

  As shown in FIG. 7B, the second extending portion 112g extends outward along the longitudinal direction X from the second edge 110q of the battery main body 110H. Since the protrusion 111d of the separator 111c does not exist, the second edge 110q is located closer to the power generation element 111 than the first edge 110p. As a result, the second extending portion 112g extends outward longer than the first extending portion 112f.

  The second extending portion 112g includes a plurality of connecting hole portions 112e that engage with a plurality of connecting pins 122i (including one connecting pin 122ii) provided in the second spacer 122. Each of the second extending portions 112g includes six connecting hole portions 112e on both sides along the short direction Y. The number of connecting hole portions 112e is not limited to six and may be two or more.

  Each connecting hole 112e is formed through the laminate film 112. As shown in FIG. 7, each connecting hole 112 e is formed along the outer edge of the laminate film 112 at a predetermined interval. As shown in FIG. 7B, each connecting hole portion 112e is formed in the second extending portion 112g in a region located outside the battery body 110H with respect to the first edge 110p.

  Even if the laminate film 112 includes the plurality of connecting hole portions 112e in the second extending portion 112g, the size along the longitudinal direction X and the short direction Y does not increase. In the other end portion 112b of the laminate film 112, the second extending portion 112g can secure a wider space than the first extending portion 112f, and includes a plurality of connecting hole portions 112e in the region. Can do. Of the six connecting holes 112e, the connecting hole 112e closest to the corner of the laminate film 112 (the right end in FIG. 7) is joined to the connecting pin 122ii.

  As shown in FIGS. 6 and 9, the electrode tab 113 is composed of an anode-side electrode tab 113A and a cathode-side electrode tab 113K. Each electrode tab 113 is externally spaced from one end 112a of the pair of laminate films 112. It extends towards. The anode-side electrode tab 113A is made of aluminum in accordance with the characteristics of the anode-side component member in the power generation element 111. The cathode-side electrode tab 113K is made of copper in accordance with the characteristics of the cathode-side constituent member in the power generation element 111.

  As shown in FIG. 9, the electrode tab 113 is formed in an L shape from the base end portion 113c adjacent to the battery body 110H to the tip end portion 113d. Specifically, the electrode tab 113 extends along one side in the longitudinal direction X from the base end portion 113c. On the other hand, the tip 113d of the electrode tab 113 is formed by being refracted along the lower side in the stacking direction Z. The shape of the tip portion 113d of the electrode tab 113 is not limited to the L shape. The tip portion 113 d of the electrode tab 113 is formed in a planar shape so as to face the bus bar 131. The electrode tab 113 may be formed in a U-shape by further extending the distal end portion 113d and folding the extended portion along the base end portion 113c toward the battery body 110H. On the other hand, the base end portion 113c of the electrode tab 113 may be formed in a wave shape or a curved shape.

  The tip portions 113d of the electrode tabs 113 are refracted to be aligned downward in the stacking direction Z as shown in FIGS. Here, as shown in FIG. 5, the assembled battery 100 includes three unit cells 110 (first cell sub-assy 100M) electrically connected in parallel and another three unit cells 110 (second cell) connected in parallel. Cell subassemblies 100N) are connected in series. Therefore, for each of the three unit cells 110, the top and bottom of the unit cell 110 are switched so that the positions of the anode side electrode tab 113A and the cathode side electrode tab 113K of the unit cell 110 intersect along the stacking direction Z. Yes.

  However, simply replacing the top and bottom for each of the three unit cells 110 causes the position of the tip 113d of the electrode tab 113 to vary in the vertical direction along the stacking direction Z. The light is adjusted and refracted so that the position of the tip 113d of 113 is aligned.

  In the first cell sub-assembly 100M shown in the lower part of FIG. 5, the anode side electrode tab 113A is arranged on the right side in the figure, and the cathode side electrode tab 113K is arranged on the left side in the figure. On the other hand, in the second cell sub-assembly 100N shown in the upper part of FIG. 5, the cathode side electrode tab 113K is arranged on the right side in the figure, and the anode side electrode tab 113A is arranged on the left side in the figure.

  Thus, even if the arrangement of the anode-side electrode tab 113A and the cathode-side electrode tab 113K is different, the tip 113d of the electrode tab 113 of the unit cell 110 is refracted downward along the stacking direction Z. Further, the tip 113d of each electrode tab 113 is disposed on the same surface side of the laminate 100S as shown in FIG. A double-sided tape 160 that adheres to a laminated member that is laminated above is attached to the unit cells 110 that are positioned on the upper surfaces of the first cell sub-assembly 100M and the second cell sub-assembly 100N.

  The pair of spacers 120 (the first spacer 121 and the second spacer 122) are disposed between the stacked unit cells 110 as shown in FIG. 3, FIG. 5, and FIG. As shown in FIG. 6, the first spacer 121 is disposed along one end 112 a of the laminate film 112 from which the electrode tab 113 of the unit cell 110 is projected. As shown in FIG. 6, the second spacer 122 is disposed along the other end 112 b of the laminate film 112. The second spacer 122 has a configuration in which the shape of the first spacer 121 is simplified. Each cell 110 is stacked with a pair of spacers 120 (first spacer 121 and second spacer 122) and then stacked along the stacking direction Z. The pair of spacers 120 (the first spacer 121 and the second spacer 122) are made of reinforced plastics having insulating properties. Hereinafter, after describing the configuration of the first spacer 121, the configuration of the second spacer 122 will be described in comparison with the configuration of the first spacer 121.

  As shown in FIGS. 6 and 8, the first spacer 121 is formed in a rectangular parallelepiped shape that is long along the short direction Y. The first spacer 121 includes mounting portions 121M and 121N at both ends in the longitudinal direction (short direction Y).

  As shown in FIG. 9B, when the first spacer 121 is stacked in a state of being attached to the unit cell 110, the upper surface 121a of the mounting portions 121M and 121N of the first spacer 121 and the first The placement portions 121M and 121N of the other first spacers 121 disposed above the one spacer 121 come into contact with each other.

  As shown in FIGS. 8 and 9B, the first spacer 121 is a position provided on the upper surface 121a of one first spacer 121 in order to perform relative positioning of the unit cells 110 to be stacked. The positioning pin 121c and a positioning hole 121d corresponding to the position of the positioning pin 121c opened in the lower surface 121b of the other first spacer 121 are fitted.

  As shown in FIG. 8, the first spacer 121 includes a locating hole 121 e along the stacking direction Z for inserting a bolt that connects a plurality of assembled batteries 100 connected along the stacking direction Z. Openings to 121M and 121N, respectively.

  As shown in FIGS. 6B and 8, the first spacer 121 is formed such that a region between the mounting portions 121 </ b> M and 121 </ b> N is cut out from the upper side in the stacking direction Z. The notched portion includes a first support surface 121g and a second support surface 121h along the longitudinal direction of the first spacer 121 (the short direction Y of the unit cell 110). The first support surface 121g is formed higher in the stacking direction Z than the second support surface 121h, and is positioned on the unit cell 110 side.

  As shown in FIG. 6, the first spacer 121 places and supports one end 112 a of the laminate film 112 from which the electrode tab 113 protrudes by the first support surface 121 g. The first spacer 121 includes a pair of connecting pins 121i protruding upward from both ends of the first support surface 121g.

  As shown in FIG. 9, the first spacer 121 abuts the electrode tab 113 from the opposite side to the bus bar 131 and supports the support portion 121j that supports the tip portion 113d of the electrode tab 113 of the unit cell 110 as the second support surface 121h. And provided on the side surface along the stacking direction Z. The support part 121j of the first spacer 121 sandwiches the front end part 113d of the electrode tab 113 together with the bus bar 131 so that the front end part 113d and the bus bar 131 are sufficiently in contact with each other.

  As shown in FIGS. 6 to 8, the second spacer 122 has a configuration in which the shape of the first spacer 121 is simplified. The second spacer 122 corresponds to a configuration in which a part of the first spacer 121 is deleted along the short direction Y of the unit cell 110. Specifically, the second spacer 122 is configured by replacing the second support surface 121h and the first support surface 121g of the first spacer 121 with a support surface 122k. Specifically, the second spacer 122 includes mounting portions 122M and 122N, like the first spacer 121. The second spacer 122 includes a support surface 122k in a portion where the region between the placement portions 122M and 122N is cut out from the upper side in the stacking direction Z. The support surface 122k places and supports the other end 112b of the laminate film 112. Similar to the first spacer 121, the second spacer 122 includes a positioning pin 122c, a positioning hole, and a locating hole 122e.

  As shown in FIGS. 6 and 7, the second spacer 122 has six connection pins 122 i (one connection pin) that engage with the six connection holes 112 e of the laminate film 112 on both sides along the short direction Y. 122i). The connecting pin 122i is a convex portion protruding in a convex shape, and is linearly provided on the support surface 122k of the second spacer 122.

  Of the six connecting pins 122i, the connecting pin 122ii (the right end in FIG. 7) corresponding to the connecting hole 112e closest to the corner of the laminate film 112 is joined to the connecting hole 112e of the laminate film 112. The laminate film 112 is fixed. Specifically, the laminate film 112 is sandwiched between the tip portion of the connecting pin 122ii and the support surface 122k of the second spacer 122.

  The leading end portion of the connecting pin 122ii passes through the connecting hole portion 112e of the laminate film 112 in the shape of the connecting pin 122i, and is pressed in a heated and softened state, so that the laminate film is expanded in the radial direction. It is deformed so as to contact 112. When the heating is released, the tip portion of the connecting pin 122ii hardens and maintains its shape.

  The connection pin 122ii (the right end in FIG. 7) can fix the laminate film 112 by joining with the connection hole 112e of the laminate film 112 even in the state of the connection pin 122i before heat welding. Specifically, the connecting pin 122i and the connecting hole 112e are bonded to each other using an adhesive, or the connecting pin 122i is buckled toward the connecting hole 112e and pressed. Also good. Further, the connection pin 122i and the connection hole 112e may be joined by fitting a protrusion provided on the outer peripheral surface of the connection pin 122i to the edge of the connection hole 112e.

  As shown in FIGS. 3 and 4, the bus bar unit 130 includes a plurality of bus bars 131 integrally. The bus bar 131 is made of a metal having conductivity, and electrically connects the tip end portions 113d of the electrode tabs 113 of different unit cells 110. The bus bar 131 is formed in a flat plate shape and stands along the stacking direction Z.

  The bus bar 131 includes an anode side bus bar 131A laser welded to the anode side electrode tab 113A of one unit cell 110 and a cathode side laser welded to the cathode side electrode tab 113K of another unit cell 110 adjacent along the stacking direction Z. The bus bar 131K is joined and integrally configured.

  As shown in FIGS. 4 and 9, the anode-side bus bar 131A and the cathode-side bus bar 131K have the same shape and are formed in an L shape. The anode-side bus bar 131A and the cathode-side bus bar 131K are superposed with the top and bottom reversed. Specifically, the bus bar 131 joins a refracted portion at one end along the stacking direction Z of the anode-side bus bar 131A and a refracted portion at one end along the stacking direction Z of the cathode-side bus bar 131K. It is integrated. As shown in FIG. 4, the anode-side bus bar 131 </ b> A and the cathode-side bus bar 131 </ b> K include a side portion 131 c along the longitudinal direction X from one end in the short-side direction Y. The side part 131 c is joined to the bus bar holder 132.

  The anode-side bus bar 131A is made of aluminum, like the anode-side electrode tab 113A. Similarly to the cathode side electrode tab 113K, the cathode side bus bar 131K is made of copper. The anode side bus bar 131A and the cathode side bus bar 131K made of different metals are joined to each other by ultrasonic joining.

  As shown in FIG. 5, when the battery pack 100 is configured by connecting a plurality of battery cells 110 connected in parallel across a plurality of sets, for example, the battery pack 100 includes a portion of the anode-side bus bar 131A. Laser welding is performed on the anode-side electrode tabs 113A of the three unit cells 110 adjacent to each other along the stacking direction Z. Similarly, the bus bar 131 laser-welds a portion of the cathode-side bus bar 131K to the cathode-side electrode tabs 113K of the three unit cells 110 adjacent to each other along the stacking direction Z.

  However, among the bus bars 131 arranged in a matrix, the bus bar 131 located at the upper right in the drawings of FIGS. 3 and 4 corresponds to the anode-side end of the 21 unit cells 110 (3 parallel 7 series). It consists only of the side bus bar 131A. This anode-side bus bar 131A is laser-bonded to the anode-side electrode tab 113A of the uppermost three unit cells 110 of the battery group 100G. Similarly, among the bus bars 131 arranged in a matrix, the bus bar 131 located at the lower left in the drawings of FIGS. 3 and 4 corresponds to the end of the cathode side of 21 unit cells 110 (3 parallel 7 series), It consists only of the cathode side bus bar 131K. The cathode side bus bar 131K is laser-bonded to the cathode side electrode tabs 113K of the three unit cells 110 at the bottom of the battery group 100G.

  As shown in FIG. 3, the bus bar holder 132 integrally holds a plurality of bus bars 131 in a matrix shape so as to face the electrode tabs 113 of each unit cell 110 that is stacked. The bus bar holder 132 is made of an insulating resin and has a frame shape.

  As shown in FIG. 4, the bus bar holder 132 is a pair of standing up along the stacking direction Z so as to be positioned on both sides in the longitudinal direction of the first spacer 121 that supports the electrode tab 113 of the unit cell 110. Each column portion 132a is provided. The pair of support columns 132a are fitted to the side surfaces of the mounting portions 121M and 121N of the first spacer 121. The pair of struts 132a are L-shaped when viewed along the stacking direction Z, and are formed in a plate shape extending along the stacking direction Z. The bus bar holder 132 is provided with a pair of auxiliary struts 132 b that are erected along the stacking direction Z so as to be located near the center of the first spacer 121 in the longitudinal direction. The pair of auxiliary struts 132b are formed in a plate shape extending along the stacking direction Z.

  As shown in FIG. 4, the bus bar holder 132 includes insulating portions 132 c that protrude between the bus bars 131 adjacent in the stacking direction Z. The insulating part 132c is formed in a plate shape extending in the short direction Y. Each insulating portion 132c is horizontally provided between the support column 132a and the auxiliary support 132b. The insulating part 132c prevents discharge by insulating between the bus bars 131 of the unit cells 110 adjacent along the stacking direction Z.

  The bus bar holder 132 may be configured by joining the supporting column part 132a, the auxiliary supporting column part 132b, and the insulating part 132c formed independently from each other, or the supporting column part 132a, the auxiliary supporting column part 132b, and the insulating part 132c are integrally formed. You may form and comprise.

As shown in FIGS. 3 and 4, the anode-side terminal 133 corresponds to the anode-side end of the battery group 100 </ b> G configured by alternately stacking the first cell sub-assemblies 100 </ b> M and the second cell sub-assemblies 100 </ b> N.
As shown in FIGS. 3 and 4, the anode-side terminal 133 is joined to the anode-side bus bar 131 </ b> A located at the upper right in the drawing among the bus bars 131 arranged in a matrix. The anode side terminal 133 is made of a metal plate having conductivity, and when viewed along the short direction Y, the one end 133b and the other end 133c are aligned along the stacking direction Z with the central portion 133a as a reference. It consists of shapes refracted in different directions. The one end 133b is laser-bonded to the anode-side bus bar 131A. The other end portion 133c connects an external input / output terminal to a hole 133d (including a screw groove) opened in the center thereof.

  As shown in FIGS. 3 and 4, the cathode side terminal 134 corresponds to the end on the cathode side of the battery group 100G configured by alternately stacking the first cell sub-assemblies 100M and the second cell sub-assemblies 100N. As shown in FIGS. 3 and 4, the cathode side terminal 134 is joined to the cathode side bus bar 131 </ b> K located at the lower left in the figure among the bus bars 131 arranged in a matrix. The cathode side terminal 134 has the same configuration as the anode side terminal 133.

  As shown in FIGS. 1 to 3, the protective cover 140 covers the bus bar unit 130 so that the bus bars 131 are short-circuited with each other, or the bus bar 131 is in contact with an external member to be short-circuited or short-circuited. To prevent. Further, the protective cover 140 causes the anode side terminal 133 and the cathode side terminal 134 to face the outside, and charges and discharges the power generation element 111 of each unit cell 110. The protective cover 140 is made of plastics having insulating properties.

  As shown in FIG. 3, the protective cover 140 is formed in a flat plate shape and stands along the stacking direction Z. The protective cover 140 has a shape in which the upper end 140b and the lower end 140c of the side surface 140a thereof are refracted along the longitudinal direction X, and is fitted to the bus bar unit 130.

  As shown in FIGS. 2 and 3, the side surface 140 a of the protective cover 140 is formed of a rectangular hole that is slightly larger than the anode side terminal 133 at a position corresponding to the anode side terminal 133 provided in the bus bar unit 130. A first opening 140d is provided. Similarly, the side surface 140a of the protective cover 140 includes a second opening 140e formed of a rectangular hole slightly larger than the cathode side terminal 134 at a position corresponding to the cathode side terminal 134 provided in the bus bar unit 130. Yes.

  As shown in FIGS. 1 and 2, the housing 150 accommodates the battery group 100 </ b> G in a state of being pressurized along the stacking direction. An appropriate surface pressure is applied to the power generation element 111 by pressing the power generation element 111 of each unit cell 110 provided in the battery group 100G with the upper pressure plate 151 and the lower pressure plate 152.

  As shown in FIGS. 1 and 2, the upper pressure plate 151 is disposed above the battery group 100G in the stacking direction Z. The upper pressure plate 151 has a pressure surface 151 a protruding downward along the stacking direction Z in the center. The power generation element 111 of each unit cell 110 is pressed downward by the pressing surface 151a. The upper pressure plate 151 includes a holding portion 151 b that extends along the longitudinal direction X from both sides along the lateral direction Y. The holding part 151b covers the placement parts 121M and 121N of the first spacer 121 or the placement parts 122M and 122N of the second spacer 122. In the center of the holding portion 151b, a locating hole 151c communicating with the positioning hole 121d of the first spacer 121 or the positioning hole 122d of the second spacer 122 along the stacking direction Z is opened. The locate hole 151c is inserted with a bolt for connecting the assembled batteries 100 to each other. The upper pressure plate 151 is made of a metal plate having a sufficient thickness.

  As shown in FIGS. 1 and 2, the lower pressure plate 152 has the same configuration as the upper pressure plate 151 and reverses the top and bottom of the upper pressure plate 151. The lower pressure plate 152 is disposed below along the stacking direction Z of the battery group 100G. The lower pressure plate 152 presses the power generation element 111 of each unit cell 110 upward by the pressure surface 151a protruding upward along the stacking direction Z.

  As shown in FIGS. 1 and 2, the pair of side plates 153 are arranged so that the upper pressure plate 151 and the lower pressure plate 152 that pressurize the battery group 100G while sandwiching the battery group 100G from above and below in the stacking direction Z are not separated from each other. The relative positions of the pressure plate 151 and the lower pressure plate 152 are fixed. The side plate 153 is made of a rectangular metal plate and stands up along the stacking direction Z. The pair of side plates 153 are joined to the upper pressure plate 151 and the lower pressure plate 152 by laser welding from both sides in the short direction Y of the battery group 100G. Each side plate 153 is subjected to seam welding or spot welding along the longitudinal direction X with respect to the portion of the upper end 153 a that is in contact with the upper pressure plate 151. Similarly, each side plate 153 is subjected to seam welding or spot welding along the longitudinal direction X with respect to the portion of the lower end 153 b that is in contact with the lower pressure plate 152. The pair of side plates 153 covers and protects both sides in the short direction Y of the battery group 100G.

  The assembled battery 100 according to the above-described embodiment has the following operational effects.

  The assembled battery 100 includes a single battery 110 and a spacer (second spacer 122). The unit cell 110 includes a battery body 110H that includes a power generation element 111 and is formed flat, an exterior member (laminate film 112) that seals the battery body 110H, and an electrode tab 113 that is led out of the laminate film 112 from the battery body 110H. And provided. The second spacer 122 was disposed between the stacked unit cells 110 and provided with a plurality of engaging portions (connecting pins 122i) for engaging the laminate film 112. The laminate film 112 has a first extending part 112f and a second extending part 112g. The first extending portion 112f extends outward from the first edge 110p of the battery body 110H along the direction intersecting the stacking direction Z (longitudinal direction X or short direction Y). The second extending portion 112g is adjacent to the first edge 110p and intersects the stacking direction Z from the second edge 110q of the battery body 110H located on the power generation element 111 side with respect to the first edge 110p (longitudinal direction X or A plurality of engaged portions that extend outward longer than the first extending portion 112f along the short direction Y), face the corners of the unit cell 110, and engage with each connecting pin 122i. Part (connecting hole part 112e). Here, at least one of the plurality of connecting hole portions 112e is joined to the corresponding engaging portion (the connecting pin 122ii).

  According to the assembled battery 100 having such a configuration, at least one of the plurality of connecting hole portions 112e provided in the second extending portion 112g of the laminate film 112 is joined to the connecting pin 122i of the second spacer 122. . In this way, in the laminate film 112, the second extending portion 112g that extends longer from the edge of the battery body 110H than the first extending portion 112f and is more easily deformed than the first extending portion 112f, Two spacers 122 can be fixed. Therefore, the assembled battery 100 can suppress the deformation of the laminate film 112 and prevent the unit cell 110 from moving.

  Furthermore, the engaging portion (the connecting pin 122i) is a convex portion protruding in a convex shape, and the engaged portion (the connecting hole portion 112e as an example of the opening portion) is a recessed portion that is recessed in a concave shape or an opening portion that penetrates. Consists of.

  According to such a configuration, the second extending portion 112g of the laminate film 112 can be fixed to the second spacer 122 by a very simple specification.

  Further, the plurality of connecting hole portions 112 e are formed along the outer edge of the laminate film 112.

  According to such a configuration, it is possible to prevent the laminate film 112 from being deformed so as to be rolled up from the second spacer 122 using the outer edge as a starting point of deformation.

  Furthermore, the connection hole 112e closest to the corner of the laminate film 112 among the plurality of connection holes 112e is joined to the corresponding connection pin 122ii.

  According to such a configuration, it is possible to effectively fix the portion including the connecting hole portion 112e which is the starting point of the laminating film 112 and is closest to the corner portion of the laminating film 112.

  In particular, according to such a configuration, it is possible to prevent the laminate film 112 containing metal from being deformed at the corners of the laminate film 112 close to the surrounding constituent members. Therefore, it is possible to sufficiently prevent the metal of the laminate film 112 exposed to the outside from coming into contact with surrounding constituent members and causing an electrical short circuit.

  Furthermore, according to such a configuration, even when the laminate film 112 is deformed so as to be lifted from the portion of the connection pin 122ii located at the end of the second spacer 122, in addition to the connection pin 122ii, the connection pin 122ii It is possible to continue to engage with a plurality of adjacent connecting pins 122i and resist the deformation. Even if the laminate film 112 is greatly deformed so as to be separated from the portion of the connection pin 122ii located at the end of the second spacer 122, at least a part of the plurality of connection pins 122i adjacent to the connection pin 122ii. The connection pin 122i can be continuously engaged to resist the deformation.

  Further, the second extending portion 112g is adjacent to both sides of the first extending portion 112f.

  According to such a configuration, deformation of the laminate film 112 can be suppressed in any of the second extending portions 112g on both sides of the laminate film 112 with the first extending portion 112f therebetween.

  Further, the second spacer 122 includes a connection pin 122ii on a support surface 122k on which the laminate film 112 is placed and supported, and the laminate film 112 is sandwiched between the tip portion of the connection pin 122ii and the support surface 122k.

  According to such a configuration, it is possible to sufficiently suppress the deformation of the laminate film 112 so that the laminate film 112 does not float from the second spacer 122 at the portion of the connecting pin 122ii.

  In particular, according to such a configuration, the laminate film 112 does not bend at the portion engaged with the connecting pin 122ii, so that the tensile strength can be improved. Furthermore, according to such a configuration, the laminate film 112 containing metal inside is deformed, so that the metal of the laminate film 112 exposed to the outside comes into contact with surrounding constituent members to cause an electrical short circuit. This can be sufficiently prevented.

  Further, the power generation element 111 includes a positive electrode 111a, a negative electrode 111b, and a separator 111c having a protruding portion 111d that is disposed between the positive electrode 111a and the negative electrode 111b while being disposed between the positive electrode 111a and the negative electrode 111b. The first edge 110p is located along the tip of the protrusion 111d.

  According to such a configuration, in order to prevent the positional deviation between the positive electrode 111a and the negative electrode 111b, the unit cell 110 having a configuration in which the protruding portions 111d of the separator 111c are fixed via the laminate film 112 is suitable. It is. That is, in the laminate film 112, the second extending portion 112g corresponding to a portion that is longer than the first extending portion 112f and easily deforms due to the absence of the protruding portion 111d of the separator 111c is used as the second spacer. It is suitable for the form which fixes to 122 and suppresses a deformation | transformation.

  Furthermore, the connection hole 112e provided in the position nearest to the 1st extension part 112f among the some connection holes 112e joins the corresponding connection pin 122i mutually.

  According to such a configuration, a difference occurs in the shape and hardness at the boundary between the first extending portion 112f and the second extending portion 112g, due to the presence or absence of the protruding portion 111d of the separator 111c, and the laminate. The part that becomes the starting point of the film 112 can be fixed. Therefore, breakage or the like due to the rising of the laminate film 112 can be prevented.

  In such a configuration, the connection pin 122i of the second spacer 122 and the connection hole 112e of the laminate film 112 are bonded to each other by, for example, using an adhesive.

  Further, the plurality of connecting hole portions 112e are formed in the second extending portion 112g in a region located outside the battery main body 110H with respect to the first edge 110p.

  According to such a configuration, a sufficient distance can be ensured between the connecting hole 112e of the second extending portion 112g and the power generation element 111. For example, even if moisture or the like enters the sealing portion of the laminate film 112 from the outside via the connecting hole 112e, the moisture or the like does not reach the power generating element 111, and the electrical characteristics of the power generating element 111 are Can be maintained. Thus, the sealing distance required to maintain the bagging structure of the power generation element 111 can be ensured.

  In addition, the present invention can be variously modified based on the configurations described in the claims, and these are also within the scope of the present invention.

  For example, in the embodiment, the laminate film 112 has been described as the configuration including the second extending portions 112g on both sides of the first extending portion 112f, but the present invention is not limited to such a configuration. As an example, the laminate film may be configured to include the second extending portion 112g only on one side of the first extending portion 112f.

  Further, in the embodiment, the engaging portion of the second spacer 122 is constituted by the convex portion (the connecting pin 122i), and the engaged portion of the laminate film 112 is constituted by the opening portion (the connecting hole portion 112e). It is not limited to a simple configuration. As an example, the engaging portion of the second spacer 122 may be constituted by a concave portion or an opening portion, and the engaged portion of the laminate film 112 may be constituted by a convex portion.

100 battery packs,
100S laminate,
100G battery group,
100M first cell sub-assembly,
100N second cell sub-assembly,
110 cell,
110H battery body,
110p first edge,
110q second edge,
111 power generation elements,
111a positive electrode,
111b negative electrode,
111c separator,
111d protrusion,
111e welding part,
112 Laminate film,
112e connecting hole (engaged part),
112f 1st extension part,
112g 2nd extension part,
113 electrode tabs,
113A anode side electrode tab,
113K cathode side electrode tab,
120 a pair of spacers,
121 first spacer,
122 second spacer,
122i connecting pin (engagement part),
122ii connecting pin (engagement member closest to the corner of the exterior member among the plurality of engagement portions),
122k support surface,
130 bus bar unit,
131 Busbar,
131A Anode-side bus bar (first bus bar),
131K cathode side bus bar (second bus bar),
132 bus bar holder,
133 Anode terminal,
134 cathode side terminal,
140 protective cover,
150,
151 Upper pressure plate,
152 lower pressure plate,
153 side plate,
160 double-sided tape,
X (longitudinal direction of the unit cells 110 intersecting with the stacking direction of the unit cells 110),
Y (crossing the stacking direction of the unit cells 110 and the short direction of the unit cells 110),
Z (stacking direction of unit cell 110).

Claims (9)

A battery body including a power generation element and formed flat; an exterior member that seals the battery body; and an electrode tab that is led out of the exterior member from the battery body; and
A spacer having a plurality of engagement portions disposed between the stacked unit cells and engaging the exterior member;
The exterior member is
A first extending portion extending outwardly from the first edge of the battery body along a direction intersecting the stacking direction;
Adjacent to the first edge and extending outward from the second edge of the battery body located on the power generation element side with respect to the first edge longer than the first extending portion along a direction intersecting the stacking direction. A second extending portion that includes a plurality of engaged portions that extend and face the corners of the unit cell and engage with each of the engaging portions,
An assembled battery in which at least one of the plurality of engaged portions is joined to the corresponding engaging portion. The engaging portion is a convex portion protruding in a convex shape,
The assembled battery according to claim 1, wherein the engaged portion includes a recessed portion that is recessed in a concave shape or an opening that penetrates the recessed portion.   The assembled battery according to claim 1, wherein the plurality of engaged portions are formed along an outer edge of the exterior member.   The said to-be-engaged part nearest to the corner | angular part of the said exterior member among several said to-be-engaged parts mutually joins with the said corresponding engaging part, The any one of Claims 1-3 Assembled battery.   The assembled battery according to any one of claims 1 to 4, wherein the second extending portion is adjacent to both sides of the first extending portion. The spacer includes the engagement portion on a support surface on which the exterior member is placed and supported.
The assembled battery according to any one of claims 1 to 5, wherein the exterior member is sandwiched between a distal end portion of the engaging portion and the support surface. The power generation element includes a positive electrode, a negative electrode, and a separator having a protruding portion that is disposed between the positive electrode and the negative electrode while partially protruding from between the positive electrode and the negative electrode.
The assembled battery according to any one of claims 1 to 6, wherein the first edge is located along a tip of the protruding portion.   The assembled battery according to claim 7, wherein among the plurality of engaged portions, the engaged portions provided at positions closest to the first extending portion are joined to the corresponding engaging portions.   The assembled battery according to claim 7 or 8, wherein the plurality of engaged portions are formed in the second extending portion in a region located outside the battery body from the first edge.