JP5830336B2 - Battery module - Google Patents

Description

  The present invention relates to a battery module in which a plurality of secondary batteries are electrically connected, and more particularly to a cooling structure for a battery module.

  A battery module mounted on a hybrid electric vehicle or a pure electric vehicle is configured by combining a large number of secondary batteries (hereinafter referred to as single battery cells) such as lithium ion batteries and nickel metal hydride batteries. The single battery cells constituting the battery module generate heat due to internal resistance during charging and discharging, and as the temperature rises, performance deterioration with respect to lifetime such as capacity reduction is likely to occur.

  It is desirable to make the temperature rise of the single battery cell as small as possible from the viewpoint of battery life. Patent Document 1 describes a battery cooling structure in which fins are provided on external terminals. The external terminal is thermally coupled to the electrode group via the current collecting terminal. In the single battery cell and the battery module described in Patent Document 1, heat generated in the electrode group during charge / discharge can be radiated from the external terminals by applying cooling air to the fins of the external terminals.

JP 2002-319388 A

  However, in the cooling structure described in Patent Document 1, it is necessary to increase the heat radiation area by providing a plurality of fins in order to obtain a sufficient cooling effect, and there is a problem that the battery module becomes large.

In the invention according to claim 1, the external terminals of the plurality of single battery cells are electrically connected to each other by the conductive member, and the plurality of single battery cells are cooled by cooling the outer surface of the battery container of the plurality of single battery cells. A battery module that is in direct contact with the conductive member and includes a heat transfer cover that covers the conductive member. The heat transfer cover is a heat conductive member having insulation properties, and is in direct contact with the battery container of the single battery cell. The battery module is characterized in that at least the conductive member and the battery container are thermally coupled to transfer heat from the conductive member to the battery container.
The invention according to claim 2 is the battery module according to claim 1, wherein the conductive member is held by a heat transfer cover.
According to a third aspect of the present invention, in the battery module according to the first or second aspect, the conductive member has a flat plate portion having a surface that is in direct contact with the heat transfer cover, and the heat transfer cover includes a conductive member. A concave accommodating portion for accommodating the flat plate portion is provided, and the accommodating portion has a bottom surface on which the flat plate portion of the conductive member is directly contacted and a side wall rising from the bottom surface so as to cover the periphery of the flat plate portion of the conductive member. A part of the end face of the side wall is in direct contact with the battery container of the single battery cell.
According to a fourth aspect of the present invention, in the battery module according to the third aspect, the side wall of the heat transfer cover is brought into contact with the surface of the single battery cell and the member holding the single battery cell, so A sealed space is formed by the surface of the battery cell and the member that holds the single battery cell.
According to a fifth aspect of the present invention, in the battery module according to the third or fourth aspect, the conductive member includes a rising portion that rises from the flat plate portion, a voltage detection terminal that is bent from the rising portion and extends parallel to the flat plate portion. The heat transfer cover is provided with a through-hole through which the rising portion of the conductive member is inserted, and the conductive member is inserted into the through-hole of the heat transfer cover, and the voltage detection terminal portion and The heat transfer cover is attached by being sandwiched by the flat plate portion.
The invention according to claim 6 is the battery module according to any one of claims 3 to 5, wherein the heat transfer cover further includes a holding portion projecting inward from the side wall of the housing portion, The flat plate portion of the conductive member is sandwiched between the bottom surface of the housing portion and the holding portion, and a portion of the holding portion is in direct contact with the battery container of the single battery cell.
The invention according to claim 7 is the battery module according to any one of claims 1 to 6, wherein each of the plurality of single battery cells is insulated to insulate the electrode group accommodated in the battery container from the battery container. The material of the heat transfer cover having a film has a thermal conductivity higher than the thermal conductivity of the insulating film, and has a volume resistivity lower than the volume resistivity of the insulating film. .
The invention according to claim 8 is the battery module according to any one of claims 1 to 7, wherein the external terminal is in direct contact with the heat transfer cover.
The invention according to claim 9 is the battery module according to any one of claims 1 to 8, the material of the conductive member is a metal, and wherein the material of the heat transfer cover is silicon rubber .
Invention, in the battery module according to any one of claims 1 to 9, a cooling plate having a coolant passage through which a cooling medium therein, and an insulating sheet, a plurality of unit cells according to claim 10 The cell is characterized in that it is thermally coupled to the cooling plate via an insulating sheet.
According to an eleventh aspect of the present invention, in the battery module according to any one of the first to tenth aspects, an external member electrically connected to a conductive member connected to another battery module or a conductive member for extracting electric power. It further comprises a conductive member for connection and an auxiliary heat transfer cover attached to the conductive member for external connection, and the auxiliary heat transfer cover is a heat conductive member having insulation properties, and is in direct contact with the battery container of the single battery cell. It is characterized by being.

  According to the present invention, the battery cell can be effectively cooled and the battery module can be miniaturized by efficiently transferring the heat generated in the electrode group during charging and discharging to the surface of the battery container.

1 is an external perspective view showing a battery module according to a first embodiment of the present invention. FIG. 2 is an exploded perspective view of the battery module shown in FIG. 1. The external appearance perspective view of a single battery cell. The exploded perspective view of a single battery cell. The perspective view which shows the winding electrode group accommodated in the battery container of a single battery cell. FIG. 6 is a sectional view taken along line VI-VI in FIG. 1. (A) is the schematic diagram which looked at the 1st cell group of the state which removed the cover shown in FIG. 2, the board | substrate, and the isolation plate from the side, (b) is the 1st cell group shown in FIG. The schematic diagram which shows the state which connected the single battery cell of this in series. The external appearance perspective view of the 1st bus bar assembly shown by FIG. The external appearance perspective view of the 1st bus bar assembly shown by FIG. FIG. 3 is an exploded perspective view of the first bus bar assembly shown in FIG. 2. The external appearance perspective view of the 2nd bus bar assembly shown by FIG. The disassembled perspective view of the 2nd bus bar assembly shown by FIG. FIG. 3 is an external perspective view of a third bus bar assembly shown in FIG. 2. FIG. 3 is an exploded perspective view of a third bus bar assembly shown in FIG. 2. The external appearance perspective view which shows the battery module which concerns on the 2nd Embodiment of this invention. FIG. 16 is an exploded perspective view of the battery module shown in FIG. 15. (A) is the schematic diagram which looked at the battery module of the state which removed the cover, the board | substrate, and the isolation plate which were shown by FIG. 16, from the upper surface, (b) is a single battery cell of the battery module shown by FIG. The schematic diagram which shows the state which connected in series. FIG. 16 is a cross-sectional view taken along line XVIII-XVIII in FIG. 15. The external appearance perspective view of the bus bar assembly shown by FIG. FIG. 17 is an exploded perspective view of the bus bar assembly shown in FIG. 16.

  Hereinafter, with reference to the drawings, the present invention is a battery module incorporated in a power storage device mounted on a hybrid electric vehicle or a pure electric vehicle, and is a prismatic lithium ion secondary battery (hereinafter referred to as a single battery cell). A description will be given of an embodiment applied to a battery module provided with a plurality of. In addition, the same code | symbol was attached | subjected to the component of the same shape and the same kind of material.

-First embodiment-
FIG. 1 is an external perspective view showing the battery module 100 according to the first embodiment of the present invention, and FIG. 2 is an exploded perspective view of the battery module 100. As shown in the figure, the depth direction is the x direction, the length direction is the y direction, and the height direction is the z direction.

  As shown in FIG. 1, the battery module 100 has a substantially rectangular parallelepiped shape, and holds a plurality of single battery cells by an integrated mechanism including an end plate, a cell separation plate, a bolt, a nut, and the like which will be described later. Yes. The battery module 100 is provided with a power cable 166 that is a wiring for extracting power.

  As shown in FIG. 2, the battery module 100 includes a large number of single battery cells 101. The unit cells 101 are juxtaposed on a cooling plate 180 disposed substantially at the center of the battery module 100 in the x (depth) direction. A heat transfer sheet 189 is interposed between the cooling plate 180 and the bottom surface of each single battery cell 101, and the single battery cell 101 is thermally coupled to the cooling plate 180 via the heat transfer sheet 189.

The material of the cooling plate 180 is a material excellent in thermal conductivity, for example, aluminum. The material of the heat transfer sheet 189 is a material having good thermal conductivity and electrical insulation, for example, silicon rubber. As the heat transfer sheet 189, it is preferable to employ an insulating sheet having a thermal conductivity of about 1 to 5 W / m · K and a volume resistivity of about 10 ¹⁰ to 10 ¹¹ Ω · cm.

  The heat transfer sheet 189 further has appropriate flexibility and adhesiveness, and both the unit cell 101 and the cooling plate 180 are arranged so that there is no gap between the bottom surface of the unit cell 101 and the cooling plate 180. Are in contact with each other.

  The cooling plate 180 is formed in a rectangular parallelepiped shape, and a refrigerant flow path (not shown) through which a cooling medium such as an ethylene glycol aqueous solution flows is linearly provided along the y direction. One end of the cooling plate 180 is provided with a refrigerant inlet 181 into which a cooling medium is introduced, and the other end of the cooling plate 180 is provided with a refrigerant outlet 182 through which the cooling medium is discharged.

  A hose, a pipe and the like (not shown) are attached to the refrigerant inlet 181 and the refrigerant outlet 182, and the cooling plate 180 is connected to a refrigerant cooling system (not shown). The cooling medium is supplied from the refrigerant cooling system to the refrigerant inlet 181, flows in the cooling plate 180 in the y direction, is discharged from the refrigerant outlet 182, and is collected by the refrigerant cooling system.

  The refrigerant cooling system (not shown) includes a pump that circulates the cooling medium in the refrigerant cooling system, a tank that serves as a buffer for temporarily storing the cooling medium, and cooling that is deprived of heat by the unit cell 101. And a radiator that cools the medium by exchanging heat with the atmosphere.

  As shown in FIG. 2, the plurality of unit cells 101 includes one surface of the cooling plate 180 (front surface in the figure, hereinafter referred to as a surface) and the other surface in the thickness direction facing the surface (hereinafter referred to as the back surface). As shown in the figure, three rows are arranged in the y (length) direction and four steps are arranged in the z (height) direction.

  As shown in the figure, the battery module 100 has components arranged symmetrically on the front surface side and the back surface side of the cooling plate 180. The cover 123, the substrate 129, the isolation plate 122, and the third bus bar assembly 193, which will be described later, are different in that they are symmetrical with respect to the cooling plate 180, but have the same functions, and therefore have the same reference numbers. Hereinafter, the components arranged on the surface side of the cooling plate 180 will be mainly described. In addition, twelve single battery cells 101 (hereinafter referred to as a first cell group) arranged on the front side of the cooling plate 180 and twelve single battery cells 101 (on the back side of the cooling plate 180) ( Hereinafter, the second cell group is connected in series by a connection bus bar 168 described later. For this reason, in the first cell group and the second cell group, the arrangement layout of the positive electrode and the negative electrode is opposite to each other. For example, the connection bus bar 164 to which the connection bus bar 168 is connected in the first cell group is connected to the negative external terminal of the single battery cell 101, and the connection bus bar 164 to which the connection bus bar 168 is connected in the second cell group is a single battery. The positive electrode external terminal of the cell 101 is connected.

  Cell separation plates 143 and 144 are interposed between the single battery cells 101 of each stage. An end plate 141 that covers the entire uppermost unit cell 101 arranged in the xy plane is disposed on the uppermost unit cell 101. An end plate 142 that covers the entire lowermost unit cell 101 arranged in the xy plane is disposed below the lowermost unit cell 101.

  The end plates 141 and 142 and the cell separation plates 143 and 144 have a wide width that comes into contact with the insertion side portions 141a, 142a, 143a, and 144a having through holes through which the bolts 130 are inserted, and the wide side surface of the unit cell 101, respectively. Side surface insulating portions 141b, 142b, 143b, and 144b are provided (see FIG. 7B).

  The end plates 141 and 142 and the cell separation plate 144 are provided with narrow side insulating portions 141c, 142c, and 144c that are in contact with the narrow side surfaces of the unit cell 101, respectively (see FIG. 7B). ). The end surfaces of the narrow side surface insulating portions 141c, 142c, and 144c are located on the same plane as the surface of the battery lid 102B of the single battery cell 101 (see FIG. 6). In addition, the end surfaces of the wide side surface insulating portions 141b, 142b, 143b, and 144b are also located on the same plane as the surface of the battery cover 102B of the single battery cell 101. The materials of the end plates 141 and 142 and the cell separation plates 143 and 144 are insulating materials, such as polypropylene, polyamide, polyether imide, polyphenylene sulfide, polyphthalamide, polybutylene terephthalate, and the like. .

  As shown in FIG. 2, on the outer side (front side in the drawing) of the single battery cells 101 constituting the first cell group in the x (depth) direction, the battery covers of all the single battery cells 101 constituting the first cell group. An isolation plate 122 covering the surface (yz plane) is disposed. A substrate 129 is disposed on the outer side (front side in the figure) of the isolation plate 122 in the x (depth) direction, and is fixed to the isolation plate 122 with screws.

  A cover 123 that covers the substrate 129 is disposed outside the substrate 129 in the x (depth) direction (front side in the drawing). The cover 123 is formed of a resin material having insulating properties. The cover 123 is for preventing intrusion of conductive foreign substances such as water, dust, oil, or a composite material, and is attached so as to cover the entire outer side surface of the isolation plate 122.

  The end plates 141 and 142 and the cell separation plates 143 and 144 are arranged so as to sandwich the single battery cell 101 and are coupled by bolts 130 and nuts 131. End plate 141 is coupled to cooling plate 180 by bolts 132. Similarly, end plate 142 is coupled to cooling plate 180 by bolts (not shown).

  The isolation plate 122 is formed with a plurality of engaging claws 122 c that protrude toward the center in the x direction and a contact portion that contacts the surface of the battery cover of the single battery cell 101. The end plates 141 and 142 are formed with engaging grooves 120c that engage with the engaging claws 122c. When the engaging claw 122c is mounted in the engaging groove 120c, the unit cell 101 is pressed toward the cooling plate 180 by the isolation plate 122.

  When the unit cell 101 is pressed to the cooling plate 180 side, the heat transfer sheet 189 having flexibility and adhesiveness is compressed by a predetermined amount, and the heat transfer sheet 189 is compressed between the battery container bottom surface of the unit cell 101 and the cooling plate 180. Adheres to the surface.

  As described above, the plurality of single battery cells 101 transfer heat by the integrated mechanism including the end plates 141 and 142, the cell separation plates 143 and 144, the isolation plate 122, the bolts 130 and 132, and the nut 131. The battery cells 101 are thermally coupled to the cooling plate 180 via the sheet 189 and are integrally held in a state where the battery cells 101 are electrically insulated from each other.

  The single battery cell 101 which comprises the battery module 100 is demonstrated. The plurality of single battery cells 101 constituting the battery module 100 has the same structure. FIG. 3 is an external perspective view of the single battery cell 101, and FIG. 4 is an exploded perspective view of the single battery cell 101. FIG. 5 is a perspective view showing the wound electrode group 170 housed in the battery container of the single battery cell 101.

  As shown in FIGS. 3 and 4, the single battery cell 101 includes a battery container having a battery can 102 </ b> A and a battery lid 102 </ b> B. Both the battery can 102A and the battery lid 102B are made of aluminum. The battery can 102A has a rectangular box shape having an opening at one end. The battery lid 102B has a rectangular flat plate shape and is welded so as to close the opening of the battery can 102A. That is, the battery lid 102B seals the battery can 102A.

As shown in FIG. 4, a wound electrode group 170 that is a power storage element is accommodated in the battery can 102 </ b> A in a state of being covered with an insulating film 179. The wound electrode group 170 and the battery container are insulated by an insulating film 179. The material of the insulating film 179 is, for example, polypropylene having a thermal conductivity of about 0.2 W / m · K and a volume resistivity of about 10 ¹⁸ Ω · cm.

  As shown in FIG. 5, the wound electrode group 170 is configured by laminating a long positive electrode 174 and a negative electrode 175 by winding them in a flat shape with a separator 173 interposed therebetween.

  The positive electrode 174 includes a positive electrode foil 171 and a positive electrode active material mixture layer 176 formed by coating a positive electrode active material mixture on both surfaces of the positive electrode foil 171. The negative electrode 175 includes a negative electrode foil 172 and a negative electrode active material mixture layer 177 formed by coating a negative electrode active material mixture on both surfaces of the negative electrode foil 172. Charging / discharging is performed between the positive electrode active material and the negative electrode active material. The positive foil 171 is an aluminum foil having a thickness of about 30 μm, and the negative foil 172 is a copper foil having a thickness of about 20 μm. The material of the separator 173 is a porous polyethylene resin.

  One end of the wound electrode group 170 in the width direction (a direction orthogonal to the winding direction) is laminated with an uncoated portion (exposed portion of the positive foil 171) where the positive electrode active material mixture layer 176 is not formed. The other portion is a portion where an uncoated portion (exposed portion of the negative electrode foil 172) where the negative electrode active material mixture layer 177 is not formed is laminated. The laminated body of the positive electrode side uncoated part and the laminated body of the negative electrode side uncoated part are respectively crushed in advance, and ultrasonic bonding with a positive electrode current collector 21 and a negative electrode current collector 31 (see FIG. 4) described later, respectively. Is done.

As shown in FIG. 3, a liquid injection unit 107 is provided in the battery lid 102 </ b> B. As shown in FIG. 4, the liquid injection part 107 has a liquid injection hole 107 a for injecting an electrolyte into the battery container. The liquid injection hole 107a is sealed by a liquid injection stopper 107b after the electrolytic solution is injected. The liquid injection stopper 107b is fixed to the battery lid 102B by welding. As the electrolytic solution, for example, a non-aqueous electrolytic solution in which a lithium salt such as lithium hexafluorophosphate (LiPF ₆ ) is dissolved in a carbonate-based organic solvent such as ethylene carbonate can be used. When the electrolytic solution is injected into the battery can 102A, the entire interior of the wound electrode group 170 is impregnated with the electrolytic solution.

  As shown in FIGS. 3 and 4, a gas discharge valve 103 is formed in the central portion of the battery lid 102 </ b> B. The gas discharge valve 103 provided on the container surface of the unit cell 101 is formed by partially thinning the battery lid 102B by pressing so that the degree of stress concentration during internal pressure action is relatively high. . As a result, when the inside of the battery can 102A reaches a predetermined pressure (for example, about 1 MPa), the gas discharge valve 103 is preferentially broken, and the gas is discharged toward the upper outside of the battery container.

  As shown in FIG. 3, the battery lid 102 </ b> B is provided with a positive terminal assembly 60 and a negative terminal assembly 70. As shown in FIG. 4, the positive terminal assembly 60 includes a positive terminal connection 61, a positive terminal plate 63, a positive connection terminal 62 connected to the positive current collector 21, a gasket 65, and a terminal block 64. have.

  The negative terminal assembly 70 includes a negative terminal connection 71, a negative terminal plate 73, a negative connection terminal 72 connected to the negative current collector 31, a gasket 65, and a terminal block 64. The positive electrode terminal plate 63 and the positive electrode connection terminal 62 constitute a positive external terminal, and the negative electrode terminal plate 73 and the negative electrode connection terminal 72 constitute a negative external terminal.

  The materials of the positive electrode terminal plate 63, the positive electrode connection terminal 62, and the positive electrode current collector 21 are all aluminum. The material of the negative electrode terminal plate 73, the negative electrode connection terminal 72, and the negative electrode current collector 31 is copper. The positive electrode terminal connecting portion 61 and the negative electrode terminal connecting portion 71 are made of a material having higher rigidity than aluminum or copper, for example, stainless steel. The material of the gasket 65 and the terminal block 64 is a resin having insulation properties such as polybutylene terephthalate, polyphenylene sulfide, and perfluoroalkoxy fluororesin.

  The positive terminal assembly 60 and the negative terminal assembly 70 have the same configuration, although the materials of the external terminals are different. The positive terminal assembly 60 and the negative terminal assembly 70 are each similarly assembled to the battery lid 102B and integrally fixed to the battery lid 102B. Therefore, the positive electrode terminal assembly 60 will be described below as a representative.

  The positive terminal plate 63 is a rectangular flat plate member, and has a circular through hole 63a and a circular through hole 63b. The positive terminal connecting portion 61 includes a rectangular flat base portion 61b and a columnar portion 61a provided upright on the base portion 61b. The terminal block 64 includes a rectangular flat base and a side wall rising from the outer edge of the base. The inner surface shape of the side wall of the terminal block 64 is formed corresponding to the outer shape of the positive terminal plate 63, and the positive terminal plate 63 is fitted inside the side wall of the terminal block 64.

  At the base of the terminal block 64, a rectangular recess 64a and a circular through hole 64b are formed. The base portion 61 b of the positive terminal connecting portion 61 is fitted into the rectangular recess 64 a of the terminal block 64. The columnar portion 61 a of the positive terminal connecting portion 61 is inserted into the through hole 63 a of the positive terminal plate 63. The base portion 61 b of the positive terminal connecting portion 61 is sandwiched between the positive terminal plate 63 and the terminal block 64.

  The gasket 65 is formed in a stepped ring shape having an opening 65a and a flange 65b. The gasket 65 is inserted into a circular through hole provided in the battery lid 102B.

  The positive electrode connection terminal 62 includes a disk-shaped flange 62c, a large-diameter upper cylindrical portion 62b erected upward from the flange 62c, and a small-diameter lower cylindrical portion 62a erected downward from the flange 62c. Have. In the positive electrode connecting terminal 62, the upper cylindrical portion 62 b is inserted into the opening 65 a of the gasket 65 and the through hole 63 b of the positive electrode terminal plate 63.

  The upper cylindrical portion 62 b of the positive electrode connection terminal 62 is caulked after being inserted into the through hole 63 b of the positive electrode terminal plate 63, and the positive electrode connection terminal 62 is fixed to the positive electrode terminal plate 63. When the upper cylindrical portion 62b is caulked, a caulking portion 62s is formed (see FIG. 6).

  As shown in FIG. 4, the positive electrode current collector 21 is bent at a substantially right angle from the seat surface portion 21a along the inner surface of the battery lid 102B and the long side of the seat surface portion 21a, and along the wide surface of the battery can 102A. A flat surface portion 21b extending toward the bottom surface of the battery can 102A and a joint portion 21d connected by a connection portion 21c provided at the lower end of the flat surface portion 21b are provided.

  A through hole 21e is provided in the seat surface portion 21a. The lower cylindrical portion 62 a of the positive electrode connection terminal 62 is caulked after being inserted into the through hole 21 e of the positive electrode current collector 21, and the positive electrode connection terminal 62 is fixed to the positive electrode current collector 21. The bonding portion 21d is ultrasonically bonded to the laminate of the positive electrode side uncoated portion (exposed portion of the positive foil 171) of the wound electrode group 170.

An example of the procedure for producing the positive terminal assembly 60 will be described.
The lower cylinder part 62a of the positive electrode connection terminal 62 is inserted into the through hole 21e of the positive electrode current collector 21, and the end surface of the lower cylinder part 62a is pressed to fix the positive electrode connection terminal 62 to the positive electrode current collector 21 by caulking. .

  The base portion 61 b of the positive terminal connecting portion 61 is fitted into the rectangular recess 64 a of the terminal block 64. The cylindrical portion 61 a of the positive terminal connecting portion 61 is inserted into the through hole 63 a of the positive terminal plate 63, and the positive terminal plate 63 is fitted inside the side wall of the terminal block 64.

  The terminal block 64 is arranged on the battery lid 102B by aligning the through hole 64b of the terminal block 64 with the through hole of the battery lid 102B. The gasket 65 is inserted through the through hole of the battery lid 102 </ b> B and the through hole 64 b of the terminal block 64. In this step, the terminal block 64 may be assembled after the gasket 65 is first inserted into the through hole of the battery lid 102B.

  The upper cylindrical portion 62b of the positive electrode connecting terminal 62 is inserted into the opening 65a of the gasket 65 and the through hole 63b of the positive electrode terminal plate 63, the upper cylindrical portion 62b is pressed, and the positive electrode connecting terminal 62 is caulked to the positive electrode terminal plate 63. Fix it. Through the above steps, the positive terminal assembly 60 is integrally fixed to the battery lid 102B.

  6 is a cross-sectional view taken along line VI-VI in FIG. As shown in FIG. 6, since the base portion of the terminal block 64 is interposed between the positive terminal connecting portion 61 and the positive terminal plate 63 and the battery lid 102B, the positive terminal connecting portion 61 and the positive terminal plate. 63 and the battery lid 102B are electrically insulated.

  The gasket 65 is provided between the positive electrode connection terminal 62 and the through hole of the battery lid 102B, and seals the battery container so that the electrolyte does not leak out. Since the gasket 65 is interposed between the positive electrode connection terminal 62 and the battery cover 102B, the positive electrode connection terminal 62 and the battery cover 102B are electrically insulated.

  As described above, the negative terminal assembly 70 (see FIG. 4) has the same configuration as the positive terminal assembly 60, is assembled in the same manner as the positive terminal assembly 60, and is integrally fixed to the battery lid 102B. . The negative electrode current collector 31 is the same as the positive electrode current collector 21 except that the material is different and the shape is symmetrical. The negative electrode terminal plate 73 and the negative electrode connection terminal 72 are the same as the positive electrode terminal plate 63 and the positive electrode connection terminal 62, respectively, except that the materials are different. The negative electrode connection terminal 72 is fixed to the negative electrode terminal plate 73 by caulking in the same manner as the positive electrode connection terminal 62 is fixed to the positive electrode terminal plate 63 by caulking. As shown in FIG. A caulking portion 72s is formed. The negative electrode terminal connection portion 71 is a member having the same material and shape as the positive electrode terminal connection portion 61. The terminal block 64 and the gasket 65 on the negative electrode side are common members with the positive electrode side.

  The negative electrode terminal assembly part 70 has a symmetrical structure with the positive electrode terminal assembly part 60, and is described as being integrally fixed to the battery lid 102B by the same assembly method as the positive electrode terminal assembly part 60. The detailed explanation is omitted.

  FIG. 7A is a schematic view of the first cell group in a state in which the cover 123, the substrate 129, and the isolation plate 122 are removed as viewed from the side. In FIG. 7A, for convenience, the nut 108 for attaching the bus bar to the unit cell 101 is omitted, and the unit cell 101, the end plates 141 and 142, and the cell separation plates 143 and 144 are indicated by two-dot chain lines. ing. FIG. 7B is a schematic diagram showing a state in which all twelve single battery cells 101 arranged in 3 rows × 4 stages are connected in series. In addition, in FIG.7 (b), illustration of the heat-transfer covers 151-153, the terminal block 64, the positive / negative terminal boards 63 and 73, etc. is abbreviate | omitted.

  7 (a) and 7 (b) show the electrical connection of the first cell group composed of 3 rows × 4 stages of single cells 101 arranged on the surface side of the cooling plate 180. FIG. In addition, the electrical connection of the second cell group constituted by the three rows × four stages of single battery cells 101 arranged on the back side of the cooling plate 180 is also connected so as to be symmetrical with the cooling plate 180 interposed therebetween. That is, the heat transfer covers 151 to 153 to which the bus bars 161 to 165 and the bus bars 161 to 165 are attached are also arranged symmetrically with the cooling plate 180 interposed therebetween.

  As shown in FIG. 7B, the negative external terminal of the uppermost leftmost single battery cell 101 and the positive external terminal of the second leftmost single battery cell 101 from the top are connected by a second bus bar 162. ing. The third bus bar 163 connects the negative external terminal of the rightmost single battery cell 101 in the second stage from the top and the positive external terminal of the rightmost single battery cell 101 in the third stage from the top. A negative external terminal of the leftmost single battery cell 101 at the third stage from the top and a positive external terminal of the leftmost single battery cell 101 at the bottom are connected by a second bus bar 162. The positive external terminal and the negative external terminal of the battery cell 101 located in the other middle are connected by the first bus bar 161. That is, all of the three rows × four stages of unit cells 101 are connected in series, and there are 12 cells between the positive electrode external terminal of the uppermost rightmost single cell 101 and the negative electrode external terminal of the lowermost right column. There is a potential difference in which the single battery cells 101 are connected in series.

  A connecting bus bar 164 is attached to the negative electrode external terminal of the lowermost unit cell 101 at the right end. As shown in FIG. 2, the connecting bus bar 164 includes the single battery cells 101 constituting the first cell group on the front surface side of the cooling plate 180 and the single battery cells constituting the second cell group on the back surface side of the cooling plate 180. 101 is connected to a connecting bus bar 168 spanned between the terminal 101 and the terminal 101. When the connection bus bar 168 is fastened to the connection bus bar 164 by the terminal bolt 169, the first cell group and the second cell group are electrically connected.

  As shown in FIG. 7B, a cable connection bus bar 165 is attached to the positive external terminal of the rightmost unit cell 101 at the uppermost stage. The cable connection bus bar 165 is connected to the power cable 166 shown in FIG.

  The first bus bar 161, the second bus bar 162, the third bus bar 163, the connecting bus bar 164, and the cable connecting bus bar 165 are respectively a first heat transfer cover 151 and a second heat transfer cover 151 shown in FIGS. The heat transfer cover 152 and the third heat transfer cover 153 are attached.

  The first bus bar 161 and the first heat transfer cover 151 constitute a first bus bar assembly 191, and the second bus bar 162 and the second heat transfer cover 152 constitute a second bus bar assembly 192, and the third bus bar 163. The connecting bus bar 164, the cable connecting bus bar 165, and the third heat transfer cover 153 constitute a third bus bar assembly 193.

The materials of the first bus bar 161, the second bus bar 162, the third bus bar 163, the connecting bus bar 164, and the cable connecting bus bar 165 are materials having good conductivity, such as copper. The first heat transfer cover 151, the second heat transfer cover 152, and the third heat transfer cover 153 are made of a material having thermal conductivity and insulation like the above-described heat transfer sheet 189, and have a thermal conductivity of 1 to 5 W, for example. / M · K and volume resistivity of 10 ¹⁰ to 10 ¹¹ Ω · cm.

  With reference to FIGS. 6 and 8 to 10, the configuration of the first bus bar assembly 191 and the thermal coupling structure of the positive and negative terminal assembly parts 60 and 70, the first bus bar assembly 191 and the battery container will be described. . 8 and 9 are external perspective views of the first bus bar assembly 191, and FIG. 10 is an exploded perspective view of the first bus bar assembly 191.

  As shown in FIG. 10, the first bus bar assembly 191 includes a first bus bar 161 and a first heat transfer cover 151. The first bus bar 161 includes a rectangular flat plate portion 161a, a rising portion 161c that rises vertically from one end of the flat plate portion 161a, and a voltage detection member that is bent perpendicularly from the rising portion 161c and extends in parallel with the flat plate portion 161a. Terminal portion 161d.

  The flat plate portion 161a is a portion that spans between the positive and negative external terminals of adjacent batteries and electrically connects the adjacent single battery cells 101 to each other. At both ends in the longitudinal direction of the flat plate portion 161a, a pair of through holes 161b into which the positive terminal connecting portion 61 and the negative terminal connecting portion 71 are inserted are formed.

  The voltage detection terminal portion 161d is a portion to which a voltage detection terminal 138 (see FIG. 6) for detecting the voltage between the electrically connected unit cells 101 is connected. The voltage detection terminal portion 161d is formed with a screw hole 161e in which a small screw 139 for terminal connection (see FIG. 6) is mounted. The voltage detection terminal 138 is connected to the substrate 129 with solder. A conductive pattern is printed on the substrate 129 in advance, and the voltage detection terminal 138 is electrically connected to a connector 128 disposed on the substrate 129.

  The first bus bar 161 is attached to the first heat transfer cover 151. As shown in FIGS. 8 and 10, the first heat transfer cover 151 is formed in a substantially rectangular parallelepiped shape. The first heat transfer cover 151 has a through hole 151g in which the columnar portion 61a of the positive electrode terminal connection portion 61 and the columnar portion 71a of the negative electrode terminal connection portion 71 are inserted, and the nuts 108 attached to the columnar portions 61a and 71a are disposed. Is formed.

  As shown in FIG. 9, the first heat transfer cover 151 is provided with a concave accommodating portion 151 a that accommodates the flat plate portion 161 a of the first bus bar 161. The accommodating portion 151a includes the terminal block 64, the positive and negative terminal plates 63 and 73 fitted to the terminal block 64, and the caulking portions 62s and 72s of the positive and negative connection terminals 62 and 72 fixed to the positive and negative terminal plates 63 and 73. It is formed in a size that can be accommodated.

  The accommodating portion 151a has a bottom surface 151b with which the flat plate portion 161a of the first bus bar 161 is directly contacted, and a side wall 151c rising from the bottom surface 151b so as to cover the periphery of the flat plate portion 161a of the first bus bar 161. The bottom surface 151b has a contact surface with which the flat plate portion 161a of the first bus bar 161 is in direct contact and a contact surface 151s with which the caulking portions 62s and 72s of the positive and negative electrode connection terminals 62 and 72 are in direct contact.

  As shown in FIG. 10, the first heat transfer cover 151 is provided with a through hole 151 d through which the rising portion 161 c of the first bus bar 161 is inserted. The shape of the through hole 151d is formed to correspond to the outer shape of the rising portion 161c of the first bus bar 161.

  As shown in FIG. 9, a pair of holding portions 151 e project from the side wall 151 c toward the inside in the housing portion 151 a of the first heat transfer cover 151. A fitting groove 151f into which the flat plate portion 161a of the first bus bar 161 is fitted is formed between the holding portion 151e and the bottom surface 151b.

  The first bus bar 161 and the first heat transfer cover 151 are formed separately. Since the material of the first bus bar 161 is copper having high rigidity and the material of the first heat transfer cover 151 is flexible silicone rubber, the pair of holding portions 151e of the first heat transfer cover 151 are opened on both sides. The first bus bar 161 can be attached in close contact with the first heat transfer cover 151 by, for example, being deformed.

  As shown in FIGS. 6 and 8, the first bus bar 161 has the rising portion 161c of the first bus bar 161 inserted through the through hole 151d of the first heat transfer cover 151, and the voltage detection terminal portion 161d and the flat plate portion 161a. Is attached so as to sandwich the first heat transfer cover 151. Furthermore, as shown in FIG. 9, the flat plate portion 161a of the first bus bar 161 is fitted into a fitting groove 151f between the holding portion 151e and the bottom surface 151b, and the bottom surface 151b and the holding portion 151e of the housing portion 151a It is pinched.

  As described above, since the first bus bar 161 is held by the first heat transfer cover 151 and the first bus bar 161 and the first heat transfer cover 151 are integrated, the first bus bar assembly 191 is connected to the unit cell. When attached to 101, the first bus bar 161 and the first heat transfer cover 151 are not separated. Therefore, the first bus bar assembly 191 can be easily attached to the single battery cell 101.

  When the cylindrical portion 61a of the positive electrode terminal connecting portion 61 and the cylindrical portion 71a of the negative electrode terminal connecting portion 71 are inserted into the through hole 161b of the first bus bar 161 and the nut 108 is attached to the cylindrical portions 61a and 71a, as shown in FIG. The first bus bar assembly 191 is fixed to the single battery cell 101.

  When the first bus bar assembly 191 is fixed to the single battery cell 101, the positive electrode terminal plate 63 and the flat plate portion 161a of the first bus bar 161 come into contact with each other and are thermally and electrically connected. Similarly, the negative terminal plate 73 and the flat plate portion 161a of the first bus bar 161 come into contact with each other and are thermally and electrically connected.

  When the first bus bar assembly 191 is fixed to the single battery cell 101, a part of the end surface of the side wall 151c of the first heat transfer cover 151 directly contacts the battery lid 102B of the single battery cell 101 as shown in FIG. Is done. A part of the end surface of the holding portion 151 e of the first heat transfer cover 151 is also directly in contact with the battery lid 102 </ b> B of the single battery cell 101. Further, the caulking portions 62 s and 72 s of the positive and negative electrode connection terminals 62 and 72 are in direct contact with the contact surface 151 s of the first heat transfer cover 151.

  As shown in FIG. 7A, when the first bus bar assembly 191 is fixed to the single battery cell 101 positioned at the uppermost stage, the end face of the side wall 151c of the first heat transfer cover 151 is shown in FIG. Is brought into contact with the battery lid 102B and the narrow side surface insulating portion 141c of the single battery cell 101 in close contact. As shown in FIG. 7A, when the first bus bar assembly 191 is fixed to the unit cells 101 located in the second and third stages from the top, as shown in FIG. The end surface of the side wall 151c of the cover 151 is brought into contact with the battery lid 102B and the narrow side surface insulating portion 144c of the single battery cell 101 in close contact with each other. As shown in FIG. 7A, when the first bus bar assembly 191 is fixed to the single battery cell 101 positioned at the lowermost stage, the end face of the side wall 151c of the first heat transfer cover 151 is shown in FIG. Is brought into contact with the battery lid 102B and the narrow side surface insulating portion 142c of the single battery cell 101 in close contact with each other. Note that the through hole 151g of the first heat transfer cover 151 is closed by the first bus bar 161 to which the positive and negative electrode terminal connecting portions 61 and 71 are connected. As a result, as shown in FIG. 6 and FIG. 7A, the outside air is blocked by the accommodating portion 151a of the first heat transfer cover 151, the surface of the unit cell 101, and the member that holds the unit cell 101. A sealed space 156 is formed.

  As described above, since the first bus bar assembly 191 is attached to the unit cell 101 (see FIG. 6), the heat generated in the wound electrode group 170 is cooled in the cooling plate 180 as follows. It is transmitted to the medium. Heat generated in the wound electrode group 170 due to charging / discharging is mainly transmitted to the positive and negative electrode current collectors 21 and 31 joined to the wound electrode group 170, and the positive and negative electrode current collectors 21 and 31 are connected to the positive and negative electrode connection terminals 62. , 72. The heat transferred to the positive and negative electrode connection terminals 62 and 72 is directly transferred to the first heat transfer cover 151 that contacts the caulking portions 62s and 72s.

  The heat transmitted to the positive and negative electrode connection terminals 62 and 72 is also transmitted from the caulking portions 62 s and 72 s to the positive and negative electrode terminal plates 63 and 73. The heat transmitted to the positive and negative terminal plates 63 and 73 is transmitted to the first bus bar 161 in contact with the positive and negative terminal plates 63 and 73. Since one surface of the flat plate portion 161a of the first bus bar 161 is in direct contact with the bottom surface 151b of the first heat transfer cover 151, the heat transferred to the first bus bar 161 is transferred from the flat plate portion 161a to the first heat transfer cover. 151. Since the rising portion 161c of the first bus bar 161 and the voltage detection terminal portion 161d are also in direct contact with the first heat transfer cover 151, the heat transmitted to the first bus bar 161 is increased by the rising portion 161c and the voltage detection terminal. It is also transmitted from the part 161d to the first heat transfer cover 151.

  The heat transmitted to the first heat transfer cover 151 is transmitted to the battery lid 102B from the end surface of the side wall 151c or the end surface of the holding portion 151e that is in direct contact with the battery lid 102B. The heat transmitted to the battery lid 102B is dispersed throughout the battery container, and the heat transmitted to the battery container is transmitted from the bottom surface of the battery can 102A to the cooling plate 180 via the heat transfer sheet 189 and flows through the cooling plate 180. Absorbed by the cooling medium. The heat absorbed by the cooling medium is transferred to the outside of the battery module 100 as the cooling medium flows through the refrigerant flow path in the cooling plate 180. As a result, the single battery cell 101 is effectively cooled.

  FIG. 11 is an external perspective view of the second bus bar assembly 192, and FIG. 12 is an exploded perspective view of the second bus bar assembly 192. As shown in FIGS. 11 and 12, the second bus bar assembly 192 is similar in shape to the first bus bar assembly 191, but has the same components. A major difference between the first bus bar assembly 191 and the second bus bar assembly 192 is that the first bus bar assembly 191 is provided with a holding portion 151e, but the second bus bar assembly 192 is provided with a holding portion 151e. This is not done.

  As shown in FIG. 12, the second bus bar assembly 192 includes a second bus bar 162 and a second heat transfer cover 152. The second bus bar 162 has a rectangular flat plate portion 162a, a rising portion 162c that rises vertically from one end of the flat plate portion 162a, and a voltage detecting portion that is bent perpendicularly from the rising portion 162c and extends in parallel with the flat plate portion 162a. Terminal portion 162d.

  The flat plate portion 162a is a portion that spans between the positive and negative external terminals of adjacent batteries and electrically connects the adjacent single battery cells 101 to each other. A pair of through-holes 162b into which the positive electrode terminal connection portion 61 and the negative electrode terminal connection portion 71 are inserted are formed at both ends in the longitudinal direction of the flat plate portion 162a.

  The voltage detection terminal portion 162d is a portion to which a voltage detection terminal 138 (see FIG. 6) that detects a voltage between the electrically connected unit cells 101 is connected. The voltage detection terminal portion 162d is formed with a screw hole 162e in which a small screw 139 for terminal connection (see FIG. 6) is mounted.

  The second bus bar 162 is attached to the second heat transfer cover 152. As shown in FIG. 12, the second heat transfer cover 152 is formed in a substantially rectangular parallelepiped shape. The second heat transfer cover 152 is inserted with the cylindrical portion 61a of the positive terminal connecting portion 61 and the cylindrical portion 71a of the negative terminal connecting portion 71, and has a through hole 152g in which the nut 108 attached to the cylindrical portions 61a and 71a is disposed. Is formed.

  As shown in FIG. 6, the second heat transfer cover 152 is provided with a concave accommodating portion 152 a that accommodates the flat plate portion 162 a of the second bus bar 162. The accommodating part 152a includes the terminal block 64, the positive and negative terminal plates 63 and 73 fitted to the terminal block 64, and the caulking portions 62s and 72s of the positive and negative electrode connection terminals 62 and 72 fixed to the positive and negative terminal plates 63 and 73. It is formed in a size that can be accommodated.

  The accommodating part 152a has the bottom face 152b with which the flat plate part 162a of the 2nd bus bar 162 is directly contacted, and the side wall 152c which stands | starts up from the bottom face 152b so that the circumference | surroundings of the flat plate part 162a of the 2nd bus bar 162 may be covered. The bottom surface 152b has a contact surface with which the flat plate portion 162a of the second bus bar 162 is in direct contact and a contact surface with which the caulking portions 62s and 72s of the positive and negative electrode connection terminals 62 and 72 are in direct contact.

  As shown in FIG. 12, the second heat transfer cover 152 is provided with a through hole 152 d through which the rising portion 162 c of the second bus bar 162 is inserted. The shape of the through hole 152d is formed to correspond to the outer shape of the rising portion 162c of the second bus bar 162.

  The second bus bar 162 and the second heat transfer cover 152 are formed separately. Since the material of the second bus bar 162 is copper having high rigidity and the material of the second heat transfer cover 152 is flexible silicone rubber, the voltage of the second bus bar 162 is inserted into the through hole 152d of the second heat transfer cover 152. The second bus bar 162 can be attached in close contact with the second heat transfer cover 152 by inserting the detection terminal portion 162d and pushing it so as to protrude from the through hole 152d.

  As shown in FIG. 11, the second bus bar 162 has the rising portion 162c of the second bus bar 162 inserted through the through hole 152d of the second heat transfer cover 152, and the second bus bar 162 is connected to the second bus bar 162 by the voltage detection terminal portion 162d and the flat plate portion 162a. The heat transfer cover 152 is attached so as to sandwich it. Since the second bus bar 162 is held by the second heat transfer cover 152 and the second bus bar 162 and the second heat transfer cover 152 are integrated, when the second bus bar assembly 192 is attached to the unit cell 101, The second bus bar 162 and the second heat transfer cover 152 are not separated. Therefore, the second bus bar assembly 192 can be easily attached to the single battery cell 101.

  When the cylindrical portion 61a of the positive electrode terminal connecting portion 61 and the cylindrical portion 71a of the negative electrode terminal connecting portion 71 are inserted into the through hole 162b of the second bus bar 162 and the nut 108 is attached to the cylindrical portions 61a and 71a, as shown in FIG. The second bus bar assembly 192 is fixed to the single battery cell 101.

  When the second bus bar assembly 192 is fixed to the single battery cell 101, the positive electrode terminal plate 63 and the flat plate portion 162a of the second bus bar 162 come into contact with each other and are thermally and electrically connected. Although not shown, similarly, the negative terminal plate 73 and the flat plate portion 162a of the second bus bar 162 are brought into contact with each other and are thermally and electrically connected.

  When the second bus bar assembly 192 is fixed to the single battery cell 101, a part of the end surface of the side wall 152c of the second heat transfer cover 152 directly contacts the battery cover 102B of the single battery cell 101 as shown in FIG. Is done. Further, the caulking portions 62 s and 72 s of the positive and negative electrode connection terminals 62 and 72 are in direct contact with the bottom surface 152 b of the second heat transfer cover 152.

  As shown in FIG. 7A, the second bus bar assembly 192 is fixed to the unit cell 101 so as to straddle the unit cell 101 located at the uppermost stage and the second stage from the top at the left end of the first cell group. Then, the end surface of the side wall 152c of the second heat transfer cover 152 is brought into contact with the battery cover 102B and the wide side surface insulating portion 143b of the single battery cell 101 so as to be in close contact with each other. Similarly, when the second bus bar assembly 192 is fixed to the single battery cell 101 so as to straddle the single battery cell 101 located at the third and lowest stages from the top at the left end of the first cell group, the second transmission The end surface of the side wall 152c of the heat cover 152 is brought into contact with the battery lid 102B and the wide side surface insulating portion 144b of the single battery cell 101 so as to be in close contact with each other. The through hole 152g of the second heat transfer cover 152 is closed by the second bus bar 162 to which the positive and negative terminal connecting portions 61 and 71 are connected. As a result, a sealed space 157 that is shut off from the outside air is formed by the accommodating portion 152a of the second heat transfer cover 152, the surface of the unit cell 101, and the member that holds the unit cell 101.

  As described above, since the second bus bar assembly 192 is attached to the single battery cell 101 (see FIG. 6), the heat generated in the wound electrode group 170 is cooled in the cooling plate 180 as follows. It is transmitted to the medium. The heat generated in the wound electrode group 170 is transmitted to the positive and negative electrode connection terminals 62 and 72 through the positive and negative electrode current collectors 21 and 31. The heat transmitted to the positive and negative electrode connection terminals 62 and 72 is directly transmitted to the second heat transfer cover 152 from the caulking portions 62 s and 72 s.

  The heat transmitted to the positive and negative electrode connection terminals 62 and 72 is also transmitted from the caulking portions 62 s and 72 s to the positive and negative electrode terminal plates 63 and 73, and is transmitted to the second heat transfer cover 152 via the second bus bar 162.

  The heat transferred to the second heat transfer cover 152 is transferred to the battery lid 102B from the end surface of the side wall 152c that is in direct contact with the battery lid 102B. The heat transmitted to the battery lid 102B is dispersed throughout the battery container, and the heat transmitted to the battery container is transmitted from the bottom surface of the battery can 102A to the cooling plate 180 via the heat transfer sheet 189 and flows through the cooling plate 180. Absorbed by the cooling medium. The heat absorbed by the cooling medium is transferred to the outside of the battery module 100 as the cooling medium flows through the refrigerant flow path in the cooling plate 180. As a result, the single battery cell 101 is effectively cooled.

  FIG. 13 is an external perspective view of the third bus bar assembly 193, and FIG. 14 is an exploded perspective view of the third bus bar assembly 193. As shown in FIGS. 13 and 14, the third bus bar assembly 193 has the same components as the first bus bar assembly 191 and the second bus bar assembly 192, although the shape is different. A major difference between the first bus bar assembly 191 and the third bus bar assembly 192 is that the first bus bar assembly 191 is provided with a holding portion 151e, but the third bus bar assembly 193 is provided with a holding portion 151e. This is not done. The major difference between the second bus bar assembly 192 and the third bus bar assembly 193 is that the second bus bar assembly 192 is only attached with the second bus bar 162 that electrically connects the battery cells 101. On the other hand, the third bus bar assembly 193 is provided with a connection bus bar 164 and a cable connection bus bar 165 so as to sandwich the third bus bar 163 that electrically connects the battery cells 101. is there.

  As shown in FIG. 14, the third bus bar assembly 193 includes a third bus bar 163, a connection bus bar 164, a cable connection bus bar 165, and a third heat transfer cover 153. The third bus bar 163 has the same shape as the second bus bar 162 described above, and is assembled to the third heat transfer cover 153 by the same assembling method.

  The third bus bar 163 includes a flat plate portion 163a that electrically connects the adjacent single battery cells 101, a rising portion 163c that is inserted in close contact with the through hole 153d of the third heat transfer cover 153, and a single battery cell. And a voltage detection terminal portion 163d to which a terminal for detecting a voltage between the terminals 101 is connected.

  The connecting bus bar 164 is a conductive member connected to the negative electrode external terminal of the lowermost unit cell 101 shown in FIG. As shown in FIG. 14, the connecting bus bar 164 includes a rectangular flat plate portion 164 a having a flat surface in contact with the negative terminal plate 73, a rising portion 164 c that rises vertically from one end of the flat plate portion 164 a, and a rising portion. It has a voltage detection terminal part 164d bent vertically from 164c and extending in parallel with the flat plate part 164a.

  The connecting bus bar 164 further includes a connecting bus bar connecting portion 164f that is bent at the other end of the flat plate portion 164a and extends in parallel with the rising portion 164c. The connecting bus bar 168 is connected to the connecting bus bar 164 at the connecting bus bar connecting portion 164f.

  The cable connecting bus bar 165 is a conductive member connected to the positive external terminal of the uppermost unit cell 101 shown in FIG. As shown in FIG. 14, the cable connection bus bar 165 includes a rectangular flat plate portion 165 a having a flat surface in contact with the positive electrode terminal plate 63, a rising portion 165 c rising vertically from one end of the flat plate portion 165 a, It has a voltage detection terminal portion 165d bent vertically from the portion 165c and extending in parallel with the flat plate portion 165a.

  The cable connection bus bar 165 further includes an inclined portion that is bent and extends at the other end of the flat plate portion 165a, a flat portion that is bent from an end portion of the inclined portion and extends in parallel with the flat plate portion 165a, and a flat surface. A cable connecting portion 165f that bends and extends from the side edge of the portion. The power cable 166 (see FIG. 1) is connected to the cable connection bus bar 165 at the cable connection portion 165f.

  As shown in FIG. 14, the third heat transfer cover 153 is formed in a substantially rectangular parallelepiped shape. The third heat transfer cover 153 has a through hole 153g in which the columnar portion 61a of the positive electrode terminal connection portion 61 and the columnar portion 71a of the negative electrode terminal connection portion 71 are inserted, and the nut 108 attached to the columnar portions 61a and 71a is disposed. Is formed.

  As shown in FIG. 7A, the third heat transfer cover 152 is provided with a concave accommodating portion 153a for accommodating the flat plate portions 163a, 164a, 165a of the bus bars 163, 164, 165. The accommodating portion 153a is sized to accommodate the terminal block 64, the positive and negative terminal plates 63 and 73, and the positive and negative electrode connection terminals 62 and 72 constituting the positive and negative terminal assembly portions 60 and 70 to which the bus bars 163, 164, and 165 are attached. Is formed.

  The accommodating portion 153a rises from the bottom surface so as to cover the bottom surface where the flat plate portions 163a, 164a, 165a of the bus bars 163, 164, 165 are in direct contact with the flat plate portions 163a, 164a, 165a of the bus bars 163, 164, 165. And a side wall 153c. The bottom surface of the accommodating portion 153a is a contact surface where the flat plate portions 163a, 164a, 165a of the bus bars 163, 164, 165 are in direct contact and a contact surface where the caulking portions 62s, 72s of the positive and negative electrode connection terminals 62, 72 are directly contacted. And have.

  As shown in FIG. 14, the third heat transfer cover 153 is provided with through holes 153d, 154d, and 155d through which the rising portions 163c, 164c, and 165c of the bus bars 163, 164, and 165 are inserted. The shapes of the through holes 153d, 154d, and 155d are formed corresponding to the outer shapes of the rising portions 163c, 164c, and 165c of the bus bars 163, 164, and 165, respectively.

  The bus bars 163, 164, 165 and the third heat transfer cover 153 are individually formed. Since the material of the third bus bar 163 is copper having high rigidity and the material of the third heat transfer cover 153 is a flexible silicone rubber, the bus bars 153d, 154d and 155d of the third heat transfer cover 153 are respectively inserted into the bus bars. The voltage detection terminal portions 163d, 164d, and 165d of 163, 164, and 165 are inserted and pushed so as to protrude from the through holes 153d, 154d, and 155d, whereby the bus bars 163, 164, and 165 are inserted into the third heat transfer cover 153. Can be attached in close contact.

  As shown in FIG. 13, the bus bars 163, 164, and 165 are inserted into the through holes 153 d, 154 d, and 155 d of the third heat transfer cover 153, respectively. The third heat transfer cover 153 is sandwiched between the detection terminal portions 163d, 164d, 165d and the flat plate portions 163a, 164a, 165a. Since the bus bars 163, 164, 165 are held by the third heat transfer cover 153 and the bus bars 163, 164, 165 and the third heat transfer cover 153 are integrated, the third bus bar assembly 193 is connected to the unit cell 101. When attaching to the bus bar, the bus bars 163, 164, 165 and the third heat transfer cover 153 are not separated. Therefore, the third bus bar assembly 193 can be easily attached to the single battery cell 101.

  The third bus bar assembly 193 is fixed to the single battery cell 101 as follows. The cylindrical portion 61a of the positive electrode terminal connecting portion 61 and the cylindrical portion 71a of the negative electrode terminal connecting portion 71 are inserted into the through hole 163b provided in the flat plate portion 163a of the third bus bar 163, and the nut 108 is attached to the cylindrical portions 61a and 71a. . The cylindrical portion 71a of the negative electrode terminal connecting portion 71 is inserted into the through hole 164b provided in the flat plate portion 164a of the connecting bus bar 164, and the nut 108 is attached to the cylindrical portion 71a. The cylindrical portion 61a of the positive electrode terminal connecting portion 61 is inserted into the through hole 165b provided in the flat plate portion 165a of the cable connecting bus bar 165, and the nut 108 is attached to the cylindrical portion 61a.

  When the third bus bar assembly 193 is fixed to the single battery cell 101, the positive electrode terminal plate 63 of the rightmost single battery cell 101 from the top and the flat plate portion 165a of the cable connection bus bar 165 shown in FIG. Abut and are thermally and electrically connected. Similarly, the negative electrode terminal plate 73 of the battery cell 101 at the right end of the second stage from the top shown in FIG. 7A is in contact with the flat plate portion 163a of the third bus bar 163 to be thermally and electrically connected. The positive electrode terminal plate 63 of the unit cell 101 at the third stage from the top shown in FIG. 7A is in contact with the flat plate portion 163a of the third bus bar 163 to be thermally and electrically connected. Similarly, the negative electrode terminal plate 73 of the lowermost unit cell 101 shown in FIG. 7A and the flat plate portion 164a of the connecting bus bar 164 come into contact with each other and are thermally and electrically connected.

  Although not shown, when the third bus bar assembly 193 is fixed to the single battery cell 101, a part of the end surface of the side wall 153c of the third heat transfer cover 153 is in direct contact with the battery cover 102B of the single battery cell 101. Further, the caulking portions 62 s and 72 s of the positive and negative electrode connection terminals 62 and 72 are in direct contact with the bottom surface of the housing portion of the third heat transfer cover 152.

  As shown in FIG. 7A, when the third bus bar assembly 193 is fixed to the four single battery cells 101 at the right end of the first cell group, the end face of the side wall 153c of the third heat transfer cover 153 is single. The battery cell 101 is in contact with the battery lid 102B and the wide side surface insulating portions 143b and 144b in close contact with each other. The through hole 153g of the third heat transfer cover 153 is closed by the third bus bar 163, the connecting bus bar 164, and the cable connecting bus bar 165 to which the positive and negative terminal connecting portions 61 and 71 are connected. As a result, a sealed space 158 that is blocked from outside air is formed by the housing portion 153a of the third heat transfer cover 153, the surface of the unit cell 101, and the member that holds the unit cell 101.

  Thus, since the 3rd bus bar assembly 193 is attached to the single battery cell 101, the heat which generate | occur | produced in the winding electrode group 170 is transmitted to the cooling medium which flows through the inside of the cooling plate 180 as follows. The heat generated in the wound electrode group 170 is transmitted to the positive and negative electrode connection terminals 62 and 72 through the positive and negative electrode current collectors 21 and 31. The heat transmitted to the positive and negative electrode connection terminals 62 and 72 is directly transmitted to the third heat transfer cover 153 from the caulking portions 62 s and 72 s.

  The heat transmitted to the positive and negative electrode connection terminals 62 and 72 is also transmitted from the caulking portions 62 s and 72 s to the positive and negative electrode terminal plates 63 and 73, and is transmitted to the third heat transfer cover 153 through the bus bars 163, 164 and 165.

  The heat transferred to the third heat transfer cover 153 is transferred to the battery lid 102B from the end surface of the side wall 153c that is in direct contact with the battery lid 102B. The heat transmitted to the battery lid 102B is dispersed throughout the battery container, and the heat transmitted to the battery container is transmitted from the bottom surface of the battery can 102A to the cooling plate 180 via the heat transfer sheet 189 and flows through the cooling plate 180. Absorbed by the cooling medium. The heat absorbed by the cooling medium is transferred to the outside of the battery module 100 as the cooling medium flows through the refrigerant flow path in the cooling plate 180. As a result, the single battery cell 101 is effectively cooled.

According to this Embodiment described above, there can exist the following effects.
(1) The heat transfer covers 151 to 153 that are in direct contact with the bus bars 161 to 165 and cover the bus bars 161 to 165 are brought into direct contact with the battery container of the single battery cell 101. Thereby, since the heat transmitted from the positive and negative external terminals to the bus bars 161 to 165 can be efficiently transmitted to the battery container via the heat transfer covers 151 to 153, the cooling performance of the single battery cell 101 can be improved. .

(2) The bus bar assemblies 191 to 193 are configured by integrating the heat transfer covers 151 to 153 and the bus bars 161 to 165. When the bus bar assemblies 191 to 193 are attached to the single battery cell 101 by the nut 108, the bus bars 161 to 165 are electrically and thermally connected to the positive and negative terminal plates 63 and 73, and at the same time, the heat transfer covers 151 to 153 are single. It is thermally connected to the battery container of the battery cell 101. Furthermore, since the bus bars 161 to 165 and the heat transfer covers 151 to 153 are integrated, when the bus bar assemblies 191 to 193 are attached to the unit cell 101, the bus bars 161 to 165 and the heat transfer covers 151 to 153 Will not separate. Therefore, the bus bar assemblies 191 to 193 can be easily attached to the single battery cell 101.

(3) As described above, the heat transfer covers 151 to 153 and the bus bars 161 to 165 are integrated to form the bus bar assemblies 191 to 193, and the heat transmitted to the bus bars 161 to 165 is passed through the heat transfer covers 151 to 153. To the battery container. Therefore, there is no need to change the structure of the single battery cell 101 itself in order to improve the cooling performance.

(4) The material of the heat transfer covers 151 to 153 has a thermal conductivity higher than that of the insulating film 179 and a volume resistivity lower than that of the insulating film 179. Therefore, insulation between the battery container and the wound electrode group 170 can be ensured, and heat generated in the wound electrode group 170 can be effectively transmitted to the battery container via the heat transfer covers 151 to 153.

(5) The caulking portions 62 s and 72 s of the positive and negative electrode connection terminals 62 and 72 are brought into direct contact with the heat transfer covers 151 to 153 to form a heat transfer path that does not pass through the bus bars 161 to 165. Thereby, the single battery cell 101 can be cooled more effectively than in the case where the caulking portions 62 s and 72 s are not brought into contact with the heat transfer covers 151 to 153.

(6) The sealed spaces 156 to 158 that are blocked from the outside air are formed so as to cover the flat plate portions 161 a to 165 a of the bus bars 161 to 165. Thereby, corrosion of the bus bars 161-165 arrange | positioned in the sealed spaces 156-158 can be suppressed, and the increase in electrical resistance can be suppressed.

-Second Embodiment-
A second embodiment of the present invention will be described with reference to FIGS. In the figure, constituent elements having the same functions as those in the first embodiment are denoted by reference numerals in the 200s instead of the 100s, and the last two digits are the same, and the differences are mainly described below. Explained.

  FIG. 15 is an external perspective view showing a battery module 200 according to the second embodiment of the present invention, and FIG. 16 is an exploded perspective view of the battery module 200. FIG. 17A is a schematic view of the battery module 200 with the cover 223, the substrate 229, and the isolation plate 222 removed, as viewed from above. In FIG. 17A, for the sake of convenience, the nut 108 for attaching the bus bars 261 and 265 to the unit cell 101 is omitted, and the unit cell 101, the end plates 241 and 242 and the cell separation plates 243 and 244 are two points. Shown with a chain line. FIG. 17B is a schematic diagram showing a state in which all 13 unit cells 101 arranged in parallel in one row are connected in series. In FIG. 17B, illustration of the heat transfer covers 251 and 253, the terminal block 64, the positive and negative terminal plates 63 and 73, etc. is omitted. 18 is a cross-sectional view taken along line XVIII-XVIII in FIG.

  As shown in FIG. 15, the battery module 200 has a substantially rectangular parallelepiped shape, and includes a plurality of single battery cells by an integrated mechanism that includes end plates 241 and 242, cell separation plates 243 and 244, and a shaft 233 described later. 101 is held. The battery module 200 is provided with a power cable 266 that is a wiring for extracting power.

  As shown in FIG. 16, in the second embodiment, 13 unit cells 101 are arranged in a row and are integrally assembled by an integration mechanism.

  Each battery cell 101 has the same configuration as in the first embodiment, although there are differences such as the position of the gas discharge valve 103 being slightly different, and therefore, the same reference numerals are given and description thereof is omitted. . Each battery cell 101 has a flat rectangular parallelepiped shape, and is arranged side by side so that wide side surfaces having a large area among the side surfaces face each other. Adjacent single battery cells 101 are arranged with their directions reversed so that the positions of the positive terminal assembly 60 and the negative terminal assembly 70 are reversed.

  As shown in FIGS. 17A and 17B, the positive external terminal and the negative external terminal of each adjacent unit cell 101 are electrically connected by a bus bar 261. That is, the plurality of single cells 101 constituting the battery module 200 according to the present embodiment are electrically connected in series.

  The positive external terminal of one single battery cell 101 (lower single battery cell 101 in the figure) and the other single battery cell 101 (upper single battery cell 101 in the figure) among the single battery cells 101 arranged at both ends. A cable connecting bus bar 265 is attached to the negative external terminal. The cable connection bus bar 265 is connected to the power cable 266 shown in FIG.

  As shown in FIGS. 15 and 16, the plurality of single battery cells 101 arranged side by side are paired with end plates 241 from both ends in the arrangement direction (longitudinal direction of the battery module 200) via cell separation plates 243 and 244. , 242. The material of the end plates 241 and 242 is, for example, aluminum. The end plates 241 and 242 have a rectangular flat plate shape corresponding to the main surface of the single battery cell 101. Through holes (not shown) are provided at both ends of the end plates 241 and 242 in the width direction, and a shaft 233 described later is inserted into the through holes.

  As shown in FIGS. 15 and 16, a plurality of cell separation plates 243 and 244 are arranged between the two end plates 241 and 242. The cell separation plate 244 is disposed between the single battery cells 101, and the cell separation plate 243 is disposed between the single battery cells 101 disposed at both ends and the end plates 241 and 242. The material of the cell separation plates 243 and 244 is an insulating resin.

  As shown in FIG. 16, the cell separation plate 244 includes a side contact portion 244 a that contacts the narrow side surface of the single battery cell 101 and an upper surface contact portion that contacts the upper surface of the single battery cell 101. 244e (see FIG. 18) and a wide side surface insulating portion 244b that is interposed between the single battery cells 101 and contacts the wide side surface of the single battery cells 101. The upper end surface of the wide side surface insulating portion 244b is located on the same plane as the surface of the battery cover 102B of the single battery cell 101. A through hole 244d is provided in the center of the side surface side contact portion 244a of the cell separation plate 244 in the height direction, and a shaft 233 is inserted into the through hole 244d.

  As described above, the shaft 233 is inserted into the through-holes provided at both ends in the width direction of the two end plates 241 and 242 and the through-holes 244d provided in each cell separation plate 244. .

  Male screws are formed at both ends of the shaft 233. By attaching nuts 231 to both ends of the shaft 233 from the outside of the end plates 241 and 242, the cell separation plates 243 and 244 sandwiched between the two end plates 241 and 242 are held in a compressed state by a predetermined amount. The Accordingly, each single battery cell 101 is held by the end plates 241 and 242 via the cell separation plates 243 and 244.

  Since the cell separation plates 243 and 244 are interposed between the single battery cells 101 or between the end plates 241 and 242 and the single battery cell 101, insulation is ensured and the single battery cells 101 A relative position in the longitudinal direction of the battery module 200 is defined.

  As shown in FIG. 16, the battery module 200 includes a cooling plate 280 made of aluminum in the lower part. A coolant channel (not shown) is provided inside the cooling plate 280. One end of the cooling plate 280 is provided with a refrigerant inlet 281 through which a cooling medium is introduced and a refrigerant outlet 282 through which the cooling medium is discharged.

  As shown in FIG. 16, a heat transfer sheet 289 is interposed between the upper surface of the cooling plate 280 and the bottom surface of the battery can 102A.

  As shown in FIG. 16, the cooling plate 280 and the cell separation plate 244 are fastened by a clip 290 made of an elastic member. As described above, since the shaft 233 is inserted into the through hole 244d of the side contact portion 244a in each cell separation plate 244, each cell separation plate 244 is integrally coupled.

  Therefore, as shown in FIG. 15, when one claw of the clip 290 is attached to the recess of the cooling plate 280 and the other claw of the clip 290 is attached to the recess of the predetermined cell separation plate 244, the elastic force of the clip 290 causes The cell separation plate 244 is pressed against the cooling plate 280 side. As shown in FIG. 18, the cell separation plate 244 presses the unit cell 101 downward by the upper surface side contact portion 244e. The heat transfer sheet 289 having flexibility is compressed by a predetermined amount, and the single battery cell 101 is thermally coupled to the cooling plate 280 via the heat transfer sheet 289.

  As shown in FIG. 16, an isolation plate 222 that covers the upper surfaces of all the unit cells 101 is disposed above the unit cells 101. A substrate 229 is disposed above the isolation plate 222 and is fixed to the isolation plate 222 with screws. A cover 223 that covers the substrate 229 is disposed above the substrate 229.

  FIG. 19 is an external perspective view of the bus bar assembly 291, and FIG. 20 is an exploded perspective view of the bus bar assembly 291. As shown in FIGS. 19 and 20, the bus bar assembly 291 is different in shape from the second bus bar assembly 192 of the first embodiment, but has similar components.

  As shown in FIG. 20, the bus bar assembly 291 includes a bus bar 261 and a heat transfer cover 251. The bus bar 261 includes a rectangular flat plate portion 261a, a rising portion 261c that rises vertically from one end of the flat plate portion 261a, and a voltage detection terminal portion that is bent perpendicularly from the rising portion 261c and extends parallel to the flat plate portion 261a. 261d.

  The flat plate portion 261a is a portion that spans between the positive and negative external terminals of adjacent batteries and electrically connects the adjacent single battery cells 101 to each other. A pair of through holes 261b into which the positive electrode terminal connecting portion 61 and the negative electrode terminal connecting portion 71 are inserted are formed at both ends in the longitudinal direction of the flat plate portion 261a.

  The voltage detection terminal portion 261d is a portion to which a voltage detection terminal 238 (see FIG. 18) for detecting a voltage between the electrically connected unit cells 101 is connected. The voltage detection terminal portion 261d is formed with a screw hole 261e in which a small screw 239 for terminal connection (see FIG. 18) is mounted.

  The bus bar 261 is attached to the heat transfer cover 251. As shown in FIG. 20, the heat transfer cover 251 is formed in a substantially rectangular parallelepiped shape. The heat transfer cover 251 is formed with a through hole 251g in which the cylindrical portion 61a of the positive electrode terminal connecting portion 61 and the cylindrical portion 71a of the negative electrode terminal connecting portion 71 are inserted, and the nuts 108 attached to the cylindrical portions 61a and 71a are disposed. ing.

  As shown in FIG. 18, the heat transfer cover 251 is provided with a concave accommodating portion 251 a that accommodates the flat plate portion 261 a of the bus bar 261. The accommodating portion 251a includes the terminal block 64, the positive and negative terminal plates 63 and 73 fitted to the terminal block 64, and the caulking portions 62s and 72s of the positive and negative connection terminals 62 and 72 fixed to the positive and negative terminal plates 63 and 73. It is formed in a size that can be accommodated.

  The accommodating portion 251a has a bottom surface 251b with which the flat plate portion 261a of the bus bar 261 is directly contacted, and a side wall 251c rising from the bottom surface 251b so as to cover the periphery of the flat plate portion 261a of the bus bar 261. The bottom surface 251b has a contact surface to which the flat plate portion 261a of the bus bar 261 is directly contacted and a contact surface to which the crimped portions 62s and 72s of the positive and negative electrode connection terminals 62 and 72 are directly contacted.

  As illustrated in FIG. 20, the heat transfer cover 251 is provided with a through hole 251 d through which the rising portion 261 c of the bus bar 261 is inserted. The shape of the through hole 251d is formed corresponding to the outer shape of the rising portion 261c of the bus bar 261.

  The bus bar 261 and the heat transfer cover 251 are formed separately. Since the material of the bus bar 261 is copper having high rigidity and the material of the heat transfer cover 251 is flexible silicone rubber, the voltage detection terminal portion 261d of the bus bar 261 is inserted into the through hole 251d of the heat transfer cover 251. The bus bar 261 can be attached in close contact with the heat transfer cover 251 by being pushed so as to protrude from the through hole 251d.

  As shown in FIG. 18 and FIG. 19, the bus bar 261 has the rising portion 261c of the bus bar 261 inserted through the through hole 251d of the heat transfer cover 251, and the voltage detection terminal portion 261d and the flat plate portion 261a detach the heat transfer cover 251. It is attached so as to hold it. Since the bus bar 261 is held by the heat transfer cover 251 and the bus bar 261 and the heat transfer cover 251 are integrated, when the bus bar assembly 291 is attached to the unit cell 101, the bus bar 261 and the heat transfer cover 251 are There is no separation. Therefore, the bus bar assembly 291 can be easily attached to the single battery cell 101.

  When the cylindrical portion 61a of the positive electrode terminal connecting portion 61 and the cylindrical portion 71a of the negative electrode terminal connecting portion 71 are inserted into the through hole 261b of the bus bar 261 and the nuts 108 are attached to the cylindrical portions 61a and 71a, as shown in FIG. The assembly 291 is fixed to the single battery cell 101.

  When the bus bar assembly 291 is fixed to the single battery cell 101, the positive electrode terminal plate 63 and the flat plate portion 261a of the bus bar 261 come into contact with each other and are thermally and electrically connected. Similarly, the negative terminal plate 73 and the flat plate portion 261a of the bus bar 261 come into contact with each other and are thermally and electrically connected.

  When the bus bar assembly 291 is fixed to the single battery cell 101, a part of the end surface of the side wall 251c of the heat transfer cover 251 is in direct contact with the battery cover 102B of the single battery cell 101 as shown in FIG. Further, the caulking portions 62 s and 72 s of the positive and negative electrode connection terminals 62 and 72 are in direct contact with the bottom surface 251 b of the heat transfer cover 251.

  As shown in FIGS. 17A and 18, when the bus bar assembly 291 is fixed to the single battery cell 101 so as to straddle between the single battery cells 101, the end face of the side wall 251 c of the heat transfer cover 251 is a single battery cell. The battery lid 102B of 101 and the wide side surface insulating portion 244b of the cell separation plate 244 are in contact with each other. The through hole 251g of the heat transfer cover 251 is closed by a bus bar 261 to which the positive and negative terminal connecting portions 61 and 71 are connected. As a result, a sealed space 256 that is blocked from outside air is formed by the housing portion 251 a of the heat transfer cover 251, the surface of the unit cell 101, and the member that holds the unit cell 101.

  Thus, since the bus bar assembly 291 is attached to the single battery cell 101 (see FIG. 18), the heat generated in the wound electrode group 170 is transferred to the cooling medium flowing in the cooling plate 280 as follows. It is transmitted. The heat generated in the wound electrode group 170 is transmitted to the positive and negative electrode connection terminals 62 and 72 through the positive and negative electrode current collectors 21 and 31. The heat transmitted to the positive and negative electrode connection terminals 62 and 72 is directly transmitted to the heat transfer cover 251 from the caulking portions 62s and 72s.

  The heat transmitted to the positive and negative electrode connection terminals 62 and 72 is transmitted from the caulking portions 62 s and 72 s to the positive and negative electrode terminal plates 63 and 73, and is transmitted to the heat transfer cover 251 through the bus bar 261.

  The heat transferred to the heat transfer cover 251 is transferred to the battery cover 102B from the end surface of the side wall 251c that is in direct contact with the battery cover 102B. The heat transmitted to the battery cover 102B is dispersed throughout the battery container, and the heat transmitted to the battery container is transmitted from the bottom surface of the battery can 102A to the cooling plate 280 via the heat transfer sheet 289 and flows in the cooling plate 280. Absorbed by the cooling medium. The heat absorbed by the cooling medium is transferred to the outside of the battery module 200 as the cooling medium flows through the refrigerant flow path in the cooling plate 280. As a result, the single battery cell 101 is effectively cooled.

  As shown in FIG. 17A, the cable connection bus bar 265 can be attached to the auxiliary heat transfer cover 255 in the same manner as the bus bar 261 is attached to the heat transfer cover 251. Thereby, the heat transmitted to the auxiliary heat transfer cover 255 from the positive and negative external terminals and the cable connecting bus bar 265 can be transmitted to the battery container.

  According to the 2nd Embodiment of this invention demonstrated above, there exists an effect similar to (1)-(6) demonstrated in 1st Embodiment.

The following modifications are also within the scope of the present invention, and one or a plurality of modifications can be combined with the above-described embodiment.
(1) In the above embodiment, a coolant channel (not shown) is formed inside the cooling plates 180 and 280, and a cooling medium such as an ethylene glycol aqueous solution is allowed to flow through the coolant channel. Although a liquid cooling method for cooling the unit cell 101 is employed, the present invention is not limited to this.

  For example, a cooling method of an air cooling method in which a plurality of fins are provided on the cooling plate and the cooling plate is cooled by applying cooling air between the fins may be employed.

(2) In the above embodiment, the cooling structure in which the cooling plates 180 and 280 are thermally coupled to the bottom surface of the battery container of the single battery cell 101 via the heat transfer sheets 189 and 289 has been described, but the present invention is limited to this. Not. A cooling plate may be thermally coupled to the side surface of the battery container.

(3) Although the cooling plates 180 and 280 are provided in the above embodiment, the present invention is not limited to this. Instead of the cooling plates 180 and 280, a unit may be provided to cool the unit cell 101 by providing a fan and applying cooling air to the wide side surface or the narrow side surface of the battery container.

(4) In the above embodiment, the heat transfer covers 151 to 153, 251 and 255 and the heat transfer sheets 189 and 289 are made of silicon rubber, but the present invention is not limited to this. Various materials having good thermal conductivity can be used. For example, as a material for the heat transfer covers 151 to 153, 251, 255 and the heat transfer sheets 189, 289, a material based on acrylic can be employed. The material of the heat transfer sheets 189 and 289 is not limited to the case of adopting a flexible material, and various materials having high insulation, thermal conductivity, and rigidity can be adopted. For example, various materials such as aluminum nitride, silicon nitride, aluminum oxide, diamond-like carbon and the like can be adopted as the material for the heat transfer sheets 189 and 289.

(5) In the above embodiment, the caulking portions 62 s and 72 s of the positive and negative electrode connection terminals 62 and 72 are thermally coupled to the heat transfer covers 151 to 153, 251 and 255, but the present invention is not limited to this, A gap may be provided between the caulking portions 62s and 72s and the heat transfer covers 151 to 153, 251 and 255. Even in this case, the heat generated in the wound electrode group 170 is transmitted through the bus bars 161 to 165, 261, and 265 that are thermally and electrically connected to the external terminals. , 255, and heat can be transferred from the heat transfer covers 151-153, 251, 255 to the battery case.

(6) In the first embodiment, the third bus bar 163 that electrically connects the unit cells 101, the connecting bus bar 164, and the cable connecting bus bar 165 are integrated with the third heat transfer cover 153. However, the present invention is not limited to this. The third heat transfer cover 153 may be divided into three, and the third bus bar 163, the connecting bus bar 164, and the cable connection bus bar 165 may be assembled to the divided heat transfer covers.

(7) In the above embodiment, the configuration in which the bus bars 161 to 165, 261, and 265 are attached by the nut 108 has been described, but the present invention is not limited to this. The bus bars 161-165, 261, 265 may be attached by laser welding. In this case, the bus bars 161 to 165, 261 and 265 and the positive and negative terminal plates 63 and 73 are overlapped and welded from above the through holes of the heat transfer covers 151 to 153, 251 and 255.

(8) In the above embodiment, the heat transfer covers 151 to 153, 251 and 255 and the bus bars 161 to 165, 261 and 265 are individually formed, and the heat transfer covers 151 to 153, 251 and 255 have flexibility. However, the present invention is not limited to this. For example, the bus bar may be integrated with the heat transfer cover by insert molding to form the bus bar assembly.

(9) The material of the positive electrode terminal plate 63, the positive electrode connection terminal 62, the positive electrode current collector 21 and the positive electrode foil 171 is not limited to aluminum, and may be an aluminum alloy. The material of the negative electrode terminal plate 73, the negative electrode connection terminal 72, the negative electrode current collector 31, and the negative electrode foil 172 is not limited to copper, and may be a copper alloy.

(10) In the above embodiment, aluminum is adopted as the material of the battery container and the cooling plates 180 and 280, but the present invention is not limited to this. Various materials having good thermal conductivity such as aluminum alloy, stainless steel, nickel, etc. can be adopted as the material of the battery container and the cooling plate.

(11) In the above embodiment, copper is adopted as the material of the bus bars 161-165, 261, 265, but the present invention is not limited to this. As the material of the bus bars 161 to 165, 261 and 265, various materials having good conductivity such as aluminum and nickel can be adopted.

(12) The storage element housed in the battery can 102A is not limited to the case where the positive electrode 174 and the negative electrode 175 are wound around the separator 173, and is not limited to a plurality of positive electrodes. It is good also as a laminated electrode group which laminated | stacked the electrode and the negative electrode through the separator.

(13) Although the lithium ion secondary battery has been described as an example of the single battery cell 101 constituting the battery modules 100 and 200, the present invention is not limited to this. For example, the present invention can be applied to a laminate-sealed battery, and besides the lithium ion secondary battery, the present invention can be applied to various batteries in which a storage element such as a nickel metal hydride battery is accommodated in a battery container.

(14) Although the battery module 100 incorporated in the power storage device mounted on the hybrid vehicle or the electric vehicle has been described in the above embodiment, the present invention is not limited to this. The present invention is applied to battery modules that can be used in power storage devices such as other electric vehicles, such as railway vehicles such as hybrid trains, passenger cars such as buses, cargo vehicles such as trucks, and industrial vehicles such as battery-powered forklift trucks. Also good. The present invention may be applied to a battery module incorporated in a stationary power storage device.

  As long as the characteristics of the present invention are not impaired, the present invention is not limited to the above-described embodiments, and other forms conceivable within the scope of the technical idea of the present invention are also included in the scope of the present invention. .

21 Positive Current Collector, 31 Negative Current Collector, 60 Positive Terminal Assembly, 61 Positive Terminal Connection, 62 Positive Connection Terminal, 63 Positive Terminal Board, 70 Negative Terminal Assembly, 71 Negative Terminal Connection, 72 Negative Connection Terminal 73, negative electrode terminal plate, 100 battery module, 101 unit cell, 122 isolation plate, 141, 142 end plate, 143, 144 cell separation plate, 151 first heat transfer cover, 151a accommodating portion, 151b bottom surface, 151c side wall, 151e Holding portion, 151f Fitting groove, 152 Second heat transfer cover, 152a receiving portion, 152b Bottom surface, 152c side wall, 153 Third heat transfer cover, 153a receiving portion, 153c side wall, 156 sealed space, 157 sealed space, 158 sealed Space, 161 first bus bar, 161a flat plate part, 161c rising part, 161d Pressure detection terminal section, 162 second bus bar, 162a flat plate section, 162c rising section, 162d voltage detection terminal section, 163 third bus bar, 163a flat plate section, 163c rising section, 163d voltage detection terminal section, 164 connection bus bar 164a flat plate portion, 164c rising portion, 164d voltage detection terminal portion, 165 cable connecting bus bar, 165a flat plate portion, 165c rising portion, 165d voltage detection terminal portion, 166 power cable, 168 connection bus bar, 170 wound electrode group 171 positive electrode foil, 172 negative electrode foil, 173 separator, 174 positive electrode, 175 negative electrode, 176 positive electrode active material mixture layer, 177 negative electrode active material mixture layer, 179 insulating film, 180 cooling plate, 189 heat transfer sheet, 200 Battery module, 222 Isolation pre 241 end plate, 243, 244 cell separation plate, 251 heat transfer cover, 251a accommodating part, 251b bottom surface, 251c side wall, 255 auxiliary heat transfer cover, 256 sealed space, 261 bus bar, 261a flat plate part, 261c rising part, 261d Voltage detection terminal section, 265 cable connection bus bar, 266 power cable, 280 cooling plate, 289 heat transfer sheet

Claims (11)

A battery module in which external terminals of a plurality of unit cells are electrically connected by a conductive member, and the plurality of unit cells are cooled by cooling an outer surface of a battery container of the plurality of unit cells. ,
A heat transfer cover that is in direct contact with the conductive member and covers the conductive member;
The heat transfer cover is a heat conductive member having an insulating property, and is in direct contact with the battery container of the single battery cell,
A battery module, wherein at least the conductive member and the battery container are thermally coupled to transfer heat from the conductive member to the battery container. The battery module according to claim 1,
The battery module, wherein the conductive member is held by the heat transfer cover. The battery module according to claim 1 or 2,
The conductive member has a flat plate portion having a surface that is in direct contact with the heat transfer cover,
The heat transfer cover is provided with a concave accommodating portion that accommodates the flat plate portion of the conductive member,
The accommodating portion has a bottom surface with which the flat plate portion of the conductive member is directly contacted, and a side wall rising from the bottom surface so as to cover the periphery of the flat plate portion of the conductive member,
Part of the end face of the side wall is in direct contact with the battery container of the single battery cell. The battery module according to claim 3, wherein
The heat transfer cover has a side wall abutting against the surface of the unit cell and the member that holds the unit cell, and a member that holds the housing part of the heat transfer cover, the surface of the unit cell, and the unit cell. A battery module, wherein a sealed space is formed. The battery module according to claim 3 or 4,
The conductive member has a rising portion that rises from the flat plate portion, and a voltage detection terminal portion that is bent from the rising portion and extends in parallel with the flat plate portion,
The heat transfer cover is provided with a through hole through which the rising portion of the conductive member is inserted,
The conductive member is attached so that the rising portion is inserted into a through hole of the heat transfer cover and the voltage detection terminal portion and the flat plate portion sandwich the heat transfer cover. Battery module. The battery module according to any one of claims 3 to 5,
The heat transfer cover further includes a holding portion protruding inward from the side wall of the housing portion,
The flat plate portion of the conductive member is sandwiched between the bottom surface of the housing portion and the holding portion,
A part of the holding part is in direct contact with the battery container of the single battery cell. The battery module according to any one of claims 1 to 6,
Each of the plurality of unit cells has an insulating film that insulates the battery group from the electrode group housed in the battery container,
The battery module is characterized in that the material of the heat transfer cover has a thermal conductivity higher than the thermal conductivity of the insulating film and a volume resistivity lower than the volume resistivity of the insulating film. . The battery module according to any one of claims 1 to 7,
The battery module, wherein the external terminal is in direct contact with the heat transfer cover. The battery module according to any one of claims 1 to 8,
Before the material of Kishirubeden member is a metal, the battery module, wherein the material of the heat transfer cover is silicon rubber. The battery module according to any one of claims 1 to 9,
A cooling plate having a refrigerant flow path through which a cooling medium flows, and an insulating sheet;
The plurality of single battery cells are thermally coupled to the cooling plate via the insulating sheet. The battery module according to any one of claims 1 to 10,
A conductive member connected to another battery module or a conductive member for external connection electrically connected to a conductive member for power extraction;
An auxiliary heat transfer cover attached to the external connection conductive member,
The auxiliary heat transfer cover is a heat conductive member having insulation properties, and is in direct contact with a battery container of the single battery cell.

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