JP2016031806A - Power storage module and inter-terminal joint member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power storage module and an inter-terminal joint member that enables firm and certain connection between the terminals of adjacent power storage batteries and can suppress reduction of durability of an inter-terminal joint member as much as possible.SOLUTION: A power storage module 10 has a power storage battery group 12M having plural stacked power storage batteries 12, and a bus bar 24 for connecting electrode terminals 22a, 22b of adjacent power storage batteries 12. The bus bar 24 has fixed portions 28a, 28b and joint portions 30a, 30b. The joint portions 30a, 30b are arranged at the outside in the width direction of a virtual plane which linearly connects the end portions of the fixed portions 28a, 28b.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a power storage module including a storage battery group in which a plurality of storage batteries are stacked, and an inter-terminal connecting member that electrically connects electrode terminals of the storage batteries adjacent to each other in the stacking direction.

  Generally, a power storage module including a storage battery group (battery module) in which a plurality of storage batteries (battery cells) are stacked is known. Since this power storage module is mounted on, for example, an electric vehicle such as a hybrid vehicle or an EV, the output voltage is set high by stacking a large number of storage batteries.

  In the power storage module, a negative electrode terminal provided in one of the storage batteries adjacent to each other and a positive electrode terminal of the other storage battery are electrically connected in series by a bus bar. And the output line is electrically connected to the electrode terminal of the storage battery arrange | positioned at the lamination direction edge part.

  As a storage battery in which this type of bus bar is used, for example, a battery pack disclosed in Patent Document 1 is known. In this battery pack, the bus bar is formed with a first through hole and a second through hole that have an inner diameter dimension equal to or less than the outer dimension of the battery cell terminal and respectively penetrate in the thickness direction. In the first through hole and the second through hole, slits extending outward from the respective inner peripheral edge portions are formed, and the terminal to be connected is fitted and fixed in the first through hole and the second through hole. Has been.

  For this reason, when each terminal fits in the first through hole and the second through hole of the bus bar, each through hole is expanded by the press-fitting of the terminal. Therefore, the outer peripheral surface of the battery cell terminal can be firmly held by the inner peripheral wall surface of each through hole.

JP2011-233491A

  By the way, in the power storage module, for example, when external vibration or the like is applied, the storage battery may be shifted in a plane direction (terminal axis direction) intersecting the stacking direction. For this reason, distortion may be caused along the stacking direction of the entire power storage module, and stress may occur in the bus bar. Furthermore, the size of each storage battery is likely to vary, and the bus bar may slip with respect to the surface direction.

  Accordingly, there is a problem that the durability of the bus bar is deteriorated and a good connection state between the bus bar and the terminal cannot be maintained. As a result, the energy density and output density of the power storage module are likely to decrease.

  The present invention solves this type of problem, and it is possible to firmly and reliably connect the terminals of the storage batteries adjacent to each other, and to suppress the deterioration of the durability of the inter-terminal connecting member as much as possible. An object of the present invention is to provide an electrical storage module and an inter-terminal connecting member.

  The power storage module according to the present invention includes a storage battery group in which a plurality of storage batteries are stacked, and an inter-terminal connection member that electrically connects electrode terminals of the storage batteries adjacent to each other in the stacking direction. The inter-terminal connecting member includes a pair of fixing portions that are fixed to the electrode terminals and a connecting portion that connects the fixing portions. Then, in a plan view of the inter-terminal connecting member, at least a part of the connecting portion is a portion of the virtual plane with respect to a virtual plane that linearly connects the end portions across the width that intersects the stacking direction of each fixing portion. It is arranged outward in the width direction.

  Moreover, in this electrical storage module, it is preferable that the connection member between terminals has plate shape, and the plate | board thickness of a connection part is comprised thinner than the plate | board thickness of a fixing | fixed part.

  Furthermore, in this power storage module, it is preferable that the pair of fixing portions have outer end portions that are separated from each other along the stacking direction, and both end portions of the connecting portion are provided at each outer end portion.

  Furthermore, in this power storage module, the fixing portion has a side surface and a main surface that intersects the side surface and is wider than the side surface, and the connecting portion intersects the side surface, the side surface, and the side surface. It is preferable that the main surface of the connecting portion and the main surface of the fixing portion extend in directions intersecting with each other.

  Moreover, in this electrical storage module, it is preferable that a connection part has a curved part which curves toward the inward from the width direction outer side of a virtual plane.

  Furthermore, in this power storage module, it is preferable that a rotation preventing hole is formed in the fixing portion.

  The inter-terminal connecting member according to the present invention electrically connects electrode terminals of storage batteries adjacent to each other in the stacking direction. This inter-terminal connecting member has a pair of fixing parts fixed to each electrode terminal and a connecting part for connecting the fixing parts. Then, in a plan view of the inter-terminal connecting member, at least a part of the connecting portion is a portion of the virtual plane with respect to a virtual plane that linearly connects the end portions across the width that intersects the stacking direction of each fixing portion. It is arranged outward in the width direction.

  Moreover, it is preferable that this inter-terminal connecting member has a plate shape, and the plate thickness of the connecting portion is configured to be thinner than the plate thickness of the fixed portion.

  Further, in this inter-terminal connecting member, it is preferable that the pair of fixing portions have outer end portions that are separated from each other along the stacking direction, and both end portions of the connecting portion are provided at each outer end portion.

  Furthermore, in this inter-terminal connecting member, the fixing portion has a side surface and a main surface that intersects the side surface and is wider than the side surface, and the connecting portion intersects the side surface and the side surface and It is preferable to have a main surface wider than the side surface. In that case, it is preferable that the main surface of a connection part and the main surface of a fixing | fixed part extend in the direction which mutually cross | intersects.

  Moreover, in this inter-terminal connecting member, it is preferable that the connecting portion has a curved portion that curves from the outside in the width direction of the imaginary plane toward the inside.

  Furthermore, in this inter-terminal connecting member, it is preferable that a rotation preventing hole is formed in the fixing portion.

  According to the present invention, at least a part of the connecting portion is disposed outward in the width direction of the virtual plane with respect to the virtual plane that linearly connects the ends of the fixed portions. For this reason, even if an external vibration, the dispersion | variation in the dimension for every storage battery, etc. generate | occur | produce, while a fixing | fixed part is reliably fixed to a terminal, a connection part can deform | transform easily. Therefore, since the connection portion has a buffer function, it is possible to suppress damage to the inter-terminal connection member as much as possible.

  As a result, the terminals of the storage batteries adjacent to each other can be firmly and reliably connected, and a decrease in durability of the inter-terminal connecting member can be suppressed as much as possible.

It is a principal part disassembled perspective explanatory drawing of the electrical storage module which concerns on the 1st Embodiment of this invention. It is a perspective explanatory view of a bus bar constituting the power storage module. It is a plane explanatory view of the bus bar. It is a plane explanatory view of a bus bar concerning a 2nd embodiment of the present invention. It is a perspective explanatory view of a bus bar concerning a 3rd embodiment of the present invention. It is a perspective explanatory view of a bus bar concerning a 4th embodiment of the present invention. It is a perspective explanatory view of a bus bar concerning a 5th embodiment of the present invention. It is a perspective explanatory view of a bus bar concerning a 6th embodiment of the present invention. It is a perspective explanatory view of a bus bar concerning a 7th embodiment of the present invention.

  As shown in FIG. 1, the electrical storage module 10 which concerns on the 1st Embodiment of this invention is mounted in electric vehicles, such as a hybrid vehicle which is not shown in figure, or EV.

  The power storage module 10 includes a storage battery group (battery module) 12M in which a plurality of storage batteries (battery cells) 12 are stacked in the horizontal direction (arrow A direction). The storage battery 12 has a rectangular shape, and is stacked in the direction of arrow A alternately with an insulating separator (holder) 14 in a state of being placed in a standing posture.

  At both ends of the storage battery group 12M in the stacking direction, rectangular (or square) end plates 18a, 18b are disposed via insulator plates (or separators 14) 16a, 16b having a heat insulating function and an insulating function. The The end plates 18a and 18b are arranged at both ends in the arrow B direction and connected in, for example, a pair of connecting bands 20a and 20b extending in the arrow A direction, and integrally hold the storage battery group 12M.

  The storage battery 12 consists of a lithium ion battery, for example, and has a rectangle (or square). A positive electrode (or negative electrode) electrode terminal 22 a and a negative electrode (or positive electrode) electrode terminal 22 b are provided on the upper surface (one cell side surface) of each storage battery 12.

  The electrode terminals 22a of one storage battery 12 and the electrode terminals 22b of the other storage battery 12 adjacent to each other are electrically connected by an inter-terminal connecting member according to the first embodiment of the present invention, for example, a bus bar 24. The electrode terminals 22a and 22b constitute a screw shaft, and with the bus bar 24 interposed, a nut 26 is screwed to fix the bus bar 24.

  As shown in FIGS. 2 and 3, the bus bar 24 is integrally formed by press-molding a conductive metal, for example, a copper plate, or casting a conductive member. The bus bar 24 includes a pair of fixing portions 28a and 28b fixed to the electrode terminals 22a and 22b, and connecting portions 30a and 30b that connect the fixing portions 28a and 28b. The fixing portions 28a and 28b have a substantially circular shape, and holes 32a and 32b are formed in the central portion.

  The fixing portions 28a, 28b have outer end portions 28ae, 28be that are separated from each other in the stacking direction (arrow A direction), and the connecting portions 30a, 30b are connected to both ends of the outer end portions 28ae, 28be in the direction of arrow B. Both end portions are provided integrally. The connecting portions 30a and 30b are raised so as to be folded upward from both sides of the outer end portions 28ae and 28be of the fixing portions 28a and 28b.

  As shown in FIG. 2, the fixing portions 28a and 28b have side surfaces 28as and 28bs, and main surfaces 28am and 28bm that intersect the side surfaces 28as and 28bs and are wider than the side surfaces 28as and 28bs. The connecting portions 30a and 30b have side surfaces 30as and 30bs and main surfaces 30am and 30bm that intersect the side surfaces 30as and 30bs and are wider than the side surfaces 30as and 30bs. The main surfaces 30am, 30bm of the coupling portions 30a, 30b and the main surfaces 28am, 28bm of the fixing portions 28a, 28b extend in a direction intersecting with each other.

  The main surfaces 28am and 28bm of the fixing portions 28a and 28b constitute a horizontal plane, while the main surfaces 30am and 30bm of the coupling portions 30a and 30b constitute a vertical surface. The plate thickness t1 of the connecting portions 30a and 30b is configured to be thinner than the plate thickness t2 of the fixed portions 28a and 28b (see FIG. 2).

  As shown in FIG. 3, in a plan view of the bus bar 24, a virtual plane 34 is formed in which ends are linearly connected across the width h <b> 1 intersecting the stacking direction of the fixing portions 28 a and 28 b. At least a part (all in the first embodiment) of the connecting portions 30a and 30b is disposed outside the virtual plane 34 in the width direction with a width h2 (> width h1). The connecting portions 30a and 30b have curved portions 30ac and 30bc that curve from the outside in the width direction of the virtual plane 34 toward the inside.

  As shown in FIG. 1, the insulator plates 16 a and 16 b are configured in a substantially flat plate shape (or may be the same as the separator 14). The end plates 18a and 18b are formed in a substantially flat plate shape, and a plurality of screw holes 36 are formed vertically at both end edges in the arrow B direction of the end plates 18a and 18b.

  The connection band 20a is formed of a horizontally long sheet metal (metal plate), and an opening 37a is formed as needed to introduce a coolant for weight reduction or cooling of the storage battery 12, for example. The connection band 20a has a U-shaped cross-section when viewed from one end in the stacking direction (arrow A direction) of the storage battery group 12M. The end portions 38a and 38a in the longitudinal direction (long side direction) of the connecting band 20a are arranged on the plate surface so as to cover the short sides of the end plates 18a and 18b.

  In each end 38a, a plurality of holes 40a are formed vertically. Each hole 40a is arranged coaxially with each screw hole 36 of the end plates 18a, 18b. The screws 42a are inserted into the holes 40a and screwed into the screw holes 36, whereby the end portions 38a of the connecting band 20a and the end plates 18a and 18b are fixed.

  Upper and lower ends of the connecting band 20a are provided with an upper bent portion 44a and a lower bent portion 46a that are bent inward in the horizontal direction from the vertical direction. The bent portion 44a extends in the stacking direction of the storage battery group 12M, and the bent portion 46a holds one lower corner of the storage battery group 12M.

  The connecting band 20b is configured in the same manner as the above-described connecting band 20a, and the same reference numerals are assigned the same reference numerals instead of the reference numerals a, and detailed descriptions thereof are omitted.

  As described above, in the power storage module 10 according to the first embodiment, as illustrated in FIG. 3, in the virtual plane 34 of the bus bar 24, the connecting portions 30 a and 30 b are disposed outward in the width direction of the virtual plane 34. ing. For this reason, even if external vibration or dimensional variation for each storage battery 12 occurs, the fixing portions 28a and 28b are securely fixed to the electrode terminals 22a and 22b, while the connecting portions 30a and 30b are easily deformed. be able to. Accordingly, since the connecting portions 30a and 30b have a buffer function, it is possible to suppress damage to the bus bar 24 as much as possible.

  Moreover, in the first embodiment, as shown in FIGS. 2 and 3, the fixing portions 28a and 28b are connected to the outer end portions 28ae and 28be that are separated from each other in the stacking direction, and both end portions of the connecting portions 30a and 30b are connected to each other. It is provided integrally. The surfaces of the connecting portions 30a and 30b and the surfaces of the fixing portions 28a and 28b extend in directions intersecting each other, and the plate thickness t1 of the connecting portions 30a and 30b is the plate of the fixing portions 28a and 28b. It is configured to be thinner than the thickness t2. Further, the connecting portions 30 a and 30 b have curved portions 30 ac and 30 bc that curve inward from the outside in the width direction of the virtual plane 34.

  As a result, the connecting portions 30a and 30b are improved in flexibility, and the stress between the connecting portions 30a and 30b and the fixing portions 28a and 28b is prevented from acting on each other. For this reason, for example, even if the storage batteries 12 are displaced in the direction of the arrow C or in the direction of the arrow B, the connecting portions 30a and 30b can be easily deformed and the stress can be eliminated. In addition, when the storage battery 12 is displaced in the direction of arrow B, it is possible to reliably prevent the loosening torque from being generated in the nut 26 screwed into the electrode terminals 22a and 22b.

  As a result, the electrode terminals 22a and 22b of the storage batteries 12 adjacent to each other can be firmly and reliably connected, and the deterioration of the durability of the electrode terminals 22a and 22b, the bus bar 24, and the like is suppressed as much as possible. Can be obtained.

  FIG. 4 is an explanatory plan view of an inter-terminal connecting member, for example, a bus bar 50 according to the second embodiment of the present invention. The same components as those of the bus bar 24 according to the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. Similarly, in the third and subsequent embodiments described below, detailed description thereof is omitted.

  The bus bar 50 includes a pair of fixing portions 52a and 52b fixed to the electrode terminals 22a and 22b, and connecting portions 30a and 30b that connect the fixing portions 52a and 52b. The fixing portions 52a and 52b have a substantially rectangular shape, and holes 32a and 32b are formed in the central portion. A pair of anti-rotation holes 54a and 54b are formed in the fixing parts 52a and 52b, respectively, inward of the holes 32a and 32b.

  In the second embodiment, when the nut 26 is fastened to the electrode terminals 22a and 22b, the rotation prevention pins 56a and 56b are inserted into the rotation prevention holes 54a and 54b. For this reason, when the nut 26 is fastened, it is possible to reliably suppress an excessive stress from being generated in the entire bus bar 50, and it is possible to obtain an effect that the damage to the bus bar 50 can be suppressed.

  FIG. 5 is a perspective explanatory view of an inter-terminal connecting member, for example, a bus bar 60 according to the third embodiment of the present invention.

  The bus bar 60 includes a pair of fixing portions 28a and 28b fixed to each electrode terminal (not shown), and connecting portions 62a and 62b that connect the fixing portions 28a and 28b. The connecting portions 62a and 62b have a flat plate shape, and are configured in the same manner as the bus bar 24 according to the first embodiment except that a curved portion is not provided. For this reason, in 3rd Embodiment, the effect substantially the same as said 1st Embodiment is acquired.

  FIG. 6 is a perspective explanatory view of an inter-terminal connecting member, for example, a bus bar 70 according to the fourth embodiment of the present invention.

  The bus bar 70 includes a pair of fixing portions 72a and 72b fixed to each electrode terminal (not shown), and a single connecting portion 74 that connects the fixing portions 72a and 72b. The fixing portions 72a and 72b are arranged in parallel in the stacking direction (arrow A direction), and the end portions of the connecting portions 74 are integrally provided at the end portions 72ae and 72be in the arrow B direction.

  The connecting portion 74 has a flat plate shape and is disposed outward in the width direction of the virtual plane 76 of the fixing portions 72a and 72b. The connecting portion 74 is not provided with a curved portion, but may be provided with this curved portion. As described above, in the fourth embodiment, substantially the same effect as in the first embodiment can be obtained.

  FIG. 7 is a perspective explanatory view of an inter-terminal connecting member, for example, a bus bar 80 according to the fifth embodiment of the present invention.

  The bus bar 80 has a pair of fixing portions 82a and 82b fixed to each electrode terminal (not shown), and a pair of connecting portions 84a and 84b connecting the fixing portions 82a and 82b. The connecting portions 84a and 84b are disposed outward in the width direction of the virtual plane 86 of the fixing portions 82a and 82b. The surfaces of the connecting portions 84a and 84b and the surfaces of the fixing portions 82a and 82b extend in the same direction, and the connecting portions 84a and 84b have curved portions 84ac and 84bc that curve upward.

  In the fifth embodiment configured as described above, the surface direction of the connecting portions 84a and 84b (surface extending direction) is different from those of the first to fourth embodiments, and is similar to the first embodiment. It is configured. Therefore, the fifth embodiment can obtain substantially the same effect as the first embodiment.

  FIG. 8 is a perspective explanatory view of an inter-terminal connecting member, for example, a bus bar 90 according to the sixth embodiment of the present invention. Note that the same components as those of the bus bar 80 according to the fifth embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the bus bar 90, a pair of connecting portions 92a and 92b are disposed between the pair of connecting portions 84a and 84b, and the connecting portions 92a and 92b are provided integrally with the fixing portions 82a and 82b. The connecting portions 92a and 92b have curved portions 92ac and 92bc that are curved upward.

  In the sixth embodiment configured as described above, the same effects as those of the fifth embodiment described above can be obtained, and in particular, the area of the conductive portion can be increased and the resistance can be easily reduced.

  FIG. 9 is a perspective explanatory view of an inter-terminal connecting member, for example, a bus bar 100 according to the seventh embodiment of the present invention.

  The bus bar 100 includes a pair of fixing portions 102a and 102b fixed to each electrode terminal (not shown), and a single connecting portion 104 that connects the fixing portions 102a and 102b. The fixing portions 102a and 102b are juxtaposed in the stacking direction (arrow A direction), and the holes 32a and 32b are formed at the central portion. The end portions of the connecting portion 104 are integrally provided on the outer peripheral end portions 102ae and 102be that are the farthest from each other of the fixing portions 102a and 102b.

  Each end portion of the connecting portion 104 rises upward from the outer peripheral end portions 102ae and 102be of the fixing portions 102a and 102b, and then extends to one end side in the arrow B direction. Both ends of the connecting portion 104 protrude outward in the width direction of the virtual plane 106 of the fixing portions 102 a and 102 b, then bend by 90 ° in directions close to each other, and extend along the virtual plane 106. A curved portion 104c that curves from the outside in the width direction of the imaginary plane 106 to the inside is provided at the center of the connecting portion 104 in the arrow A direction.

  The main surfaces 102am and 102bm of the fixing portions 102a and 102b constitute a horizontal plane, while the main surface 104m of the connecting portion 104 constitutes a vertical surface. In the seventh embodiment configured as described above, substantially the same effect as in the first embodiment can be obtained.

DESCRIPTION OF SYMBOLS 10 ... Power storage module 12 ... Storage battery 12M ... Storage battery group 14 ... Separator 18a, 18b ... End plate 20a, 20b ... Connection band 22a, 22b ... Electrode terminal 24, 50, 60, 70, 80, 90, 100 ... Busbar 26 ... Nut 28a, 28b, 52a, 52b, 72a, 72b, 82a, 82b, 102a, 102b ... fixed portions 30a, 30b, 62a, 62b, 74, 84a, 84b, 92a, 92b, 104 ... connecting portions 30ac, 30bc, 104c ... Curved portions 32a, 32b ... holes 34, 76, 106 ... virtual planes 54a, 54b ... anti-rotation holes 84ac, 84bc, 92ac, 92bc ... curved portions

Claims (12)

A storage battery group in which a plurality of storage batteries are stacked;
An inter-terminal connecting member for electrically connecting the electrode terminals of the storage batteries adjacent to each other in the stacking direction;
A power storage module comprising:
The inter-terminal connecting member includes a pair of fixing portions fixed to each electrode terminal;
A connecting portion for connecting the fixed portions;
And having
In a plan view of the inter-terminal connection member, at least a part of the connection portion is the virtual plane with respect to a virtual plane in which ends are linearly connected across the width of each fixing portion intersecting the stacking direction. An electrical storage module, which is disposed outward in the width direction. The power storage module according to claim 1, wherein the inter-terminal connecting member has a plate shape,
The electrical storage module according to claim 1, wherein a thickness of the connecting portion is configured to be thinner than a thickness of the fixed portion.   3. The power storage module according to claim 1, wherein the pair of fixing portions have outer end portions that are separated from each other along the stacking direction, and both end portions of the connecting portion are provided at each outer end portion. The electrical storage module characterized by the above-mentioned. 4. The power storage module according to claim 1, wherein the fixing portion includes a side surface and a main surface that intersects the side surface and is wider than the side surface, and the connecting portion includes a side surface. And a main surface that intersects the side surface and is wider than the side surface,
The power storage module, wherein the main surface of the connecting portion and the main surface of the fixed portion extend in directions intersecting each other.   5. The power storage module according to claim 4, wherein the connecting portion has a curved portion that curves from the outside in the width direction toward the inside in the virtual plane.   The power storage module according to any one of claims 1 to 5, wherein the fixing portion is formed with a rotation preventing hole. An inter-terminal connecting member that electrically connects electrode terminals of storage batteries adjacent to each other in the stacking direction,
A pair of fixing parts fixed to each electrode terminal;
A connecting portion for connecting the fixed portions;
And having
In a plan view of the inter-terminal connection member, at least a part of the connection portion is the virtual plane with respect to a virtual plane in which ends are linearly connected across the width of each fixing portion intersecting the stacking direction. The inter-terminal connecting member, which is disposed outward in the width direction of the. The inter-terminal connecting member according to claim 7, wherein the inter-terminal connecting member has a plate shape.
The inter-terminal coupling member is characterized in that the thickness of the connecting portion is thinner than the thickness of the fixed portion.   The inter-terminal connecting member according to claim 7 or 8, wherein the pair of fixing portions have outer end portions that are separated from each other along the stacking direction, and both end portions of the connecting portion are at each outer end portion. An inter-terminal connecting member, which is provided. 10. The inter-terminal connection member according to claim 7, wherein the fixing portion has a side surface and a main surface that intersects the side surface and is wider than the side surface, and the connection portion is A side surface and a main surface that intersects the side surface and is wider than the side surface,
The inter-terminal connecting member, wherein the main surface of the connecting portion and the main surface of the fixing portion extend in directions intersecting each other.   The inter-terminal connecting member according to claim 10, wherein the connecting portion has a curved portion that curves inward from the outside in the width direction of the virtual plane inward.   12. The inter-terminal connection member according to claim 7, wherein an anti-rotation hole is formed in the fixing portion.

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