JP2013243079A - Power storage module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power storage module which prevents leakage of a coolant in a housing and achieves compactification.SOLUTION: A power storage module 10 includes: a battery pack 100; a cooling structure 190 that is formed including a cooling plate 140 and a heat pipe 145 having a heat radiation part 145c at one end side; a refrigerant pipe 160 having a refrigerant passage 160i in which a coolant circulates; and a housing 150 housing the battery pack 100 and the cooling structure 190 therein, the housing 150 where the refrigerant pipe 160 is attached to the exterior. Multiple electric cells 101 forming the battery pack 100 are respectively and thermally coupled to one surface of the cooling plate 140. The heat pipe 145 is thermally coupled to the other surface of the cooling plate 140. A heat radiation part 145c of the heat pipe 145 and the refrigerant pipe 160 are thermally coupled through the cooling plate 140, a metal block 170, and the housing 150.

Description

  The present invention relates to a power storage module, and more particularly to a cooling structure for a power storage module.

  A power storage module mounted on a hybrid electric vehicle or a pure electric vehicle includes a housing and a plurality or a single assembled battery housed in the housing. The assembled battery 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. A single battery cell generates heat due to internal resistance during charging and discharging, and as the temperature rises, performance deterioration related to life such as capacity reduction is more 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. As a method for cooling the single battery cells constituting the assembled battery, there is a method in which the surface of the battery container of the single battery cell is thermally coupled to a cooling plate to cool the single battery cell.

  Patent Document 1 proposes an assembled battery having a configuration in which the bottom surfaces of a plurality of single battery cells are thermally coupled to one surface of a cooling plate. The cooling plate has a cooling liquid flow path that absorbs heat transmitted from the bottom surface of the unit cell and transfers the absorbed heat to the outside of the assembled battery.

JP 2010-277863 A

  The refrigerant pipe of the cooling plate of the assembled battery described in Patent Literature 1 is configured to be supplied with a cooling liquid by a cooling mechanism, and the cooling plate is provided with an inlet side connection portion and an outlet side connection portion of the refrigerant pipe. ing.

  For this reason, when the assembled battery described in Patent Document 1 is housed in a housing and attached to a vehicle, when an impact or vibration is applied to the vehicle, cooling is performed from a connection portion between the cooling mechanism and the refrigerant pipe of the cooling plate. The liquid may leak into the housing. In addition, when accommodating the assembled battery of patent document 1 in two or more in a housing | casing, since the connection part of a cooling mechanism and the refrigerant | coolant piping of a cooling plate increases, there exists a possibility that coolant may leak, so that there are many assembled batteries. Get higher.

  Further, when the assembled battery described in Patent Document 1 is housed in a housing and attached to a vehicle, it is necessary to secure an installation space for a connection pipe for connecting the refrigerant pipe and the cooling mechanism in the housing. There is also a problem that becomes large.

  The present invention relates to an assembled battery in which a plurality of unit cells are electrically connected, a cooling plate, a cooling structure including a heat pipe having a heat radiating portion on one end side, and a refrigerant through which the refrigerant flows. A refrigerant flow path forming body having a flow path, and a housing in which the assembled battery and the cooling structure are accommodated inside, and the refrigerant flow path forming body is attached to the outside. The heat pipe is thermally coupled to one surface, the heat pipe is thermally coupled to the other surface of the cooling plate, and at least the heat radiating portion of the heat pipe and the refrigerant flow path forming body are thermally coupled via the housing. It is the electrical storage module characterized by the above-mentioned.

  According to the present invention, a power storage module having a cooling structure capable of effectively cooling a plurality of single battery cells, which can prevent leakage of coolant in the housing and can be made compact. A power storage module that can be provided can be provided.

1 is an external perspective view of a power storage module according to a first embodiment of the present invention. The II-II line | wire cross-sectional schematic diagram of FIG. The plane schematic diagram of the electrical storage module of FIG. The perspective view which shows a single battery cell. The perspective view which shows the winding electrode group accommodated in the battery container of a single battery cell. The plane schematic diagram which shows the cooling structure of an electrical storage module. FIG. 7 is a schematic sectional view taken along line VII-VII in FIG. 6. The figure which shows a cooling system. The cross-sectional schematic diagram of the electrical storage module which concerns on the 2nd Embodiment of this invention. The plane schematic diagram of the electrical storage module which concerns on the 2nd Embodiment of this invention. The cross-sectional schematic diagram of the electrical storage module which concerns on the 3rd Embodiment of this invention. The plane schematic diagram of the electrical storage module which concerns on the 3rd Embodiment of this invention. The figure which shows the electrical storage module which concerns on the modification of this invention. The figure which shows the electrical storage module which concerns on the modification of this invention.

  Hereinafter, with reference to the drawings, the present invention is a power storage module incorporated in a power storage device mounted on a hybrid electric vehicle or a pure electric vehicle, and a prismatic lithium ion secondary battery (hereinafter referred to as a single battery cell). An embodiment applied to a plurality of power storage modules will be described.

-First embodiment-
FIG. 1 is an external perspective view of a power storage module 10 according to an embodiment of the present invention. 2 is a schematic cross-sectional view taken along the line II-II in FIG. 1, and FIG. 3 is a schematic plan view of the power storage module 10 in FIG. In FIG. 1, the casing 150 that houses the assembled battery 100, the refrigerant pipe 160, and the gas discharge duct 110 are not shown. In FIG. 2, the gas exhaust duct 110 is indicated by a two-dot chain line, and in FIG. 3, the illustration of the gas exhaust duct 110 and the upper surface plate constituting the housing 150 are omitted. In the present embodiment, the side where positive electrode external terminal 104 and negative electrode external terminal 105 are provided is described as the upper side of assembled battery 100, and the side where cooling structure 190 is provided is described as the lower side of assembled battery 100. As shown in FIG. 1, the vertical direction of the assembled battery 100 is the Z direction, the arrangement direction of the unit cells 101, that is, the longitudinal direction of the assembled battery 100 is the X direction, and the directions orthogonal to the X direction and the Z direction, That is, the description will be made assuming that the height direction of the assembled battery 100 is the Y direction.

  As shown in FIGS. 1-3, the electrical storage module 10 is the assembled battery 100, the cooling structure 190, and the housing | casing 150 which accommodates the assembled battery 100 and the cooling structure 190 inside (refer FIG. 2 and FIG. 3). And a refrigerant pipe 160 (see FIGS. 2 and 3) attached to the outside of the housing 150. The casing 150 has a sealed structure and is made of a material having excellent thermal conductivity such as aluminum.

  The assembled battery 100 has eight single battery cells 101. The plurality of single battery cells 101 are arranged side by side, and are configured to include a pair of end plates 120A and 120B, a plurality of battery holders 125 arranged between the single battery cells 101, and a shaft 130. It is integrally assembled by the mechanism.

  Each single battery cell 101 has a flat rectangular parallelepiped shape, and is arranged side by side so that main surfaces 102c (see FIG. 4) having a large area among side surfaces face each other. Adjacent unit cells 101 are arranged with their directions reversed so that the positions of the positive external terminal 104 and the negative external terminal 105 protruding from the battery cover 102B of the single cell 101 are reversed.

  As shown in FIGS. 1 to 3, the positive electrode external terminal 104 and the negative electrode external terminal 105 of each adjacent unit cell 101 are electrically connected by a bus bar 109 that is a metal plate-like conductive member. That is, the plurality of single cells 101 constituting the power storage module 10 according to the present embodiment are electrically connected in series.

  As shown in FIG. 1, the positive external terminal 104 of one single battery cell 101 (single battery cell 101 on the front side in the figure) among the single battery cells 101 arranged at both ends, and the other single battery cell 101 (see FIG. 1). A negative battery external terminal 105 of the inner cell unit 101) is electrically connected to other power storage modules (not shown) in series or in parallel by a conductive member (not shown), or for power extraction (not shown). It is connected to the wiring by a conductive member (not shown).

  As shown in FIGS. 1 to 3, the plurality of unit cells 101 arranged side by side are sandwiched by a pair of end plates 120 </ b> A and 120 </ b> B from both ends in the X direction via a battery holder 125. The end plates 120A and 120B have a rectangular flat plate shape corresponding to the main surface 102c (see FIG. 4) of the single battery cell 101.

  A plurality of battery holders 125 are disposed between the pair of end plates 120A and 120B. The material of the battery holder 125 is an insulating resin. The battery holder 125 has an insulating part that comes into contact with the main surface 102c (see FIG. 4) of the single battery cell 101.

  A shaft 130 is inserted into through holes (not shown) provided at both ends in the Y direction of the pair of end plates 120A, 120B and each battery holder 125.

  Male screws are formed at both ends of the shaft 130. By attaching nuts 131 to both ends of the shaft 130 from the outside of the end plates 120A, 120B, the battery holder 125 sandwiched between the pair of end plates 120A, 120B is held in a compressed state. For this reason, each single battery cell 101 is held by the end plates 120 </ b> A and 120 </ b> B via the respective battery holders 125.

  Since the battery holders 125 having insulation properties are interposed between the single battery cells 101 or between the end plates 120A and 120B and the single battery cells 101, insulation is ensured and each single battery cell 101 is also secured. Relative position is defined.

  The single battery cell 101 which comprises the assembled battery 100 is demonstrated. The plurality of single battery cells 101 has the same structure. FIG. 4 is a perspective view showing the single battery cell 101, and FIG. 5 is a perspective view showing the wound electrode group 170 accommodated in the battery container of the single battery cell 101. FIG. 5 shows a state where the winding end side of the wound electrode group 170 is developed.

  As shown in FIG. 4, the single battery cell 101 includes a rectangular battery container including 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 laser-welded so as to close the opening of the battery can 102A. That is, the battery lid 102B seals the battery can 102A.

  The battery container has a hollow rectangular parallelepiped shape, wide main surfaces 102c face each other, narrow narrow surfaces 102d face each other, and the surface of the battery lid 102B faces the bottom surface 102e of the battery can 102A. ing.

  As shown in FIG. 5, the wound electrode group 170 as a charge / discharge element is formed 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. ing. The wound electrode group 170 is accommodated in the battery can 102A in a state covered with an insulating case (not shown) made of polypropylene or the like.

  As shown in FIG. 5, 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.

  As shown in FIG. 4, a positive electrode external terminal 104 and a negative electrode external terminal 105 are disposed on the battery lid 102B. The material of the positive external terminal 104 is aluminum, and the material of the negative external terminal 105 is copper. The positive external terminal 104 and the negative external terminal 105 are inserted into through holes provided in the vicinity of both ends of the battery lid 102B through gaskets 106 made of an insulating resin material. The gasket 106 is provided between the positive electrode external terminal 104 and the through hole of the battery cover 102B and between the negative electrode external terminal 105 and the through hole of the battery cover 102B, so that the electrolyte does not leak out. The container is sealed.

  The positive external terminal 104 is a positive electrode of the wound electrode group 170, that is, a laminated portion of an uncoated portion (exposed portion of the positive foil 171) on the positive electrode side, through an aluminum positive electrode collector (not shown) (see FIG. 5). ) Is electrically connected. The negative electrode external terminal 105 is connected to a negative electrode of the wound electrode group 170 via a copper negative electrode current collector (not shown), that is, a laminated portion of an uncoated portion (exposed portion of the negative electrode foil 172) on the negative electrode side (see FIG. 5). Is electrically connected.

  Male screws are formed in the columnar portions of the positive external terminal 104 and the negative external terminal 105 that are exposed to the outside of the unit cell 101. As described above, the positive external terminal 104 and the negative external terminal 105 of the adjacent unit cells 101 are electrically connected by the bus bar 109 made of a metal plate as shown in FIG. The bus bar 109 is fastened to the positive external terminal 104 and the negative external terminal 105 by a nut (not shown).

As shown in FIG. 4, a liquid injection part 107 is provided in the battery lid 102 </ b> B. The liquid injection part 107 has a liquid injection hole for injecting an electrolytic solution into the battery container. The liquid injection hole is sealed with a liquid injection plug after the electrolyte is injected. The liquid injection stopper 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 container, the entire inner area of the wound electrode group 170 is impregnated with the electrolytic solution.

  As shown in FIG. 4, a gas discharge valve 103 is formed in the center portion of the battery lid 102B. 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. 2, a gas discharge duct (hereinafter simply referred to as a duct 110) that guides the gas discharged from each gas discharge valve 103 of each of the plurality of unit cells 101 to the outside of the vehicle, as shown in FIG. 2. .) Is provided. Duct 110 is formed so as to extend along the longitudinal direction (X direction) of battery pack 100. A gas exhaust path is formed inside the duct 110. That is, the inside of the duct 110 is hollow.

  An opening for introducing gas into the duct 110 is formed at a position corresponding to the gas discharge valve 103 of each single battery cell 101 in the duct 110. A seal member (not shown) is disposed at a connection portion between the gas exhaust valve 103 and the duct 110. One end of the duct 110 in the longitudinal direction is formed as a joint part 119 and penetrates the casing 150 and protrudes to the outside. The joint portion 119 is connected to a hose (not shown) that guides gas to the outside of the vehicle.

  The cooling structure of the single battery cell 101 will be described. 6 is a schematic plan view showing the cooling structure of the power storage module 10, and FIG. 7 is a schematic cross-sectional view taken along the line VII-VII in FIG. In FIG. 6, the cooling structure 190, the casing 150, and the refrigerant pipe 160 are illustrated, and other configurations are omitted.

  As shown in FIGS. 2 and 6, the cooling structure 190 disposed in the housing 150 includes a cooling plate 140 disposed below the assembled battery 100, and between the cooling plate 140 and the assembled battery 100. It includes a heat conductive sheet 189 interposed, a heat pipe 145 coupled to the lower surface of the cooling plate 140, and a metal block 155 coupled to the upper surface of the end of the cooling plate 140 and the inner surface of the housing 150. ing.

  The cooling plate 140 has a rectangular flat plate shape, and is disposed on the bottom surface 102 e side of the plurality of single battery cells 101 as shown in FIGS. 2 and 7. The material of the cooling plate 140 is a material excellent in thermal conductivity, for example, aluminum. The cooling plate 140 is disposed over the entire lower surface of the assembled battery 100, and as shown in FIGS. 1 and 2, one end portion in the X direction of the cooling plate 140 is provided with a protruding portion 141 protruding outward from the assembled battery 100. It has been.

  As shown in FIG. 2, a heat conductive sheet 189 is interposed between the upper surface of the cooling plate 140 and the bottom surface 102e of the battery can 102A. The heat conductive sheet 189 is a sheet based on silicon and has good heat conductivity and good electrical insulation. It is preferable to employ an insulating sheet having a thermal conductivity of about 1 to 5 W / m · K as the thermal conductive sheet 189.

  The heat conductive sheet 189 has moderate flexibility and adhesiveness, and the unit cell 101 and the cooling plate 140 are formed so that there is no gap between the bottom surface 102e of the battery can 102A and the top surface of the cooling plate 140. It is in close contact with both. In other words, the single battery cell 101 has the bottom surface 102 e in close contact with the top surface of the cooling plate 140 via the heat conductive sheet 189. The single battery cell 101 is attached in a state of being pressed against the heat conductive sheet 189. Thereby, the heat conductive sheet 189 having flexibility is compressed by a predetermined amount, and the single battery cell 101 is thermally coupled to the cooling plate 140 via the heat conductive sheet 189.

  As shown in FIGS. 2, 6 and 7, two heat pipes 145 are connected to the lower surface of the cooling plate 140 by soldering or the like. Each heat pipe 145 is arranged in parallel to the X direction which is the arrangement direction of the unit cells 101. In the present embodiment, the cylindrical heat pipe 145 is crushed in advance so as to increase the contact area between the outer surface of the heat pipe 145 and the cooling plate 140, and as shown in FIG. A flat portion 145P is formed on the heat pipe 145.

  As shown in FIG. 2, the heat pipe 145 includes a heat receiving part (evaporating part) located below the single battery cell 101 and a heat radiating part protruding from the assembled battery 100 so as to be located below the metal block 155 described later ( Condensing part) 145c, and the working fluid is sealed inside. The heat pipe 145 absorbs heat when the liquid-phase working fluid evaporates in the heat receiving portion, and the vapor-phase working fluid reaches the heat radiating portion 145c where it condenses and releases heat. The liquid phase working fluid condensed by the release of heat is returned to the heat receiving part. Such a cycle is repeated, and heat is transferred from the heat receiving portion to the heat radiating portion. In the present embodiment, a wick for assisting the circulation is provided on the inner wall of the heat pipe 145.

  The heat pipe 145 is disposed so as to be positioned below all the unit cells 101. A heat radiating portion 145c provided on one end side of the heat pipe 145 extends below a metal block 155 described later, and is connected to the lower surface of the protruding portion 141 of the cooling plate 140 by soldering or the like. In other words, the metal block 155 is disposed so as to face the heat radiating portion 145 c of the heat pipe 145 through the protruding portion 141 of the cooling plate 140. The material of the metal block 155 is a material excellent in thermal conductivity, for example, aluminum.

  As shown in FIG. 1, the metal block 155 has a rectangular parallelepiped shape, and extends in the Y direction so as to be orthogonal to the heat pipe 145. As shown in FIG. 2, the metal block 155 has a lower surface that serves as a plate contact surface that comes into contact with the upper surface of the protrusion 141 of the cooling plate 140 and one side that comes into contact with the inner surface of the housing 150. The contact surface 190a (see FIG. 1) is used. The metal block 155 is placed on each of the cooling plate 140 and the housing 150 in a state where the plate contact surface is in contact with the upper surface of the cooling plate 140 and the housing contact surface 190 a is in contact with the housing 150. Welded.

  As shown in FIGS. 2 and 6, the outer surface of the housing 150 is welded in a state in which the refrigerant pipe 160 is in contact therewith. The material of the refrigerant pipe 160 is a material excellent in thermal conductivity, for example, aluminum. The refrigerant pipe 160 is a cylindrical pipe and extends in the Y direction so as to be orthogonal to the heat pipe 145. The refrigerant pipe 160 is disposed so as to face the metal block 155 so that the casing 150 is sandwiched between the metal block 155 and the refrigerant pipe 160. In other words, the refrigerant pipe 160 and the housing contact surface 190a are arranged to face each other with the housing 150 therebetween.

  As shown in FIG. 2, the refrigerant pipe 160 is provided with a refrigerant flow path 160i through which a coolant such as an ethylene glycol aqueous solution flows. As shown in FIGS. 3 and 4, one end of the refrigerant pipe 160 is provided with a refrigerant inlet portion 161 into which the coolant is introduced, and the other end of the refrigerant pipe 160 has a refrigerant outlet portion 162 through which the coolant is discharged. Is provided.

  It is as follows when the thermal coupling relationship of the members which comprise the cooling structure of the electrical storage module 10 concerning this Embodiment is put together. The bottom surfaces 102e of the plurality of unit cells 101 are thermally coupled to the upper surface of the cooling plate 140 via the heat conductive sheet 189, and the heat pipe 145 is thermally coupled to the lower surface of the cooling plate 140. The heat radiation part 145c of the heat pipe 145 is thermally coupled to the protrusion 141 of the cooling plate 140, and the plate contact surface of the metal block 155 is thermally coupled to the upper surface of the protrusion 141 of the cooling plate 140. . The housing contact surface 190 a of the metal block 155 is thermally coupled to the inner surface of the housing 150, and the refrigerant pipe 160 is thermally coupled to the outer surface of the housing 150.

  Since the power storage module 10 has a cooling structure that is thermally coupled in this way, the heat generated in the single battery cell 101 during the charge / discharge operation is mainly generated in the refrigerant pipe 160 as follows. It is transferred to the coolant flowing through the refrigerant flow path 160 i and transferred to the outside of the power storage module 10. The heat transferred from the plurality of single cells 101 to the cooling plate 140 is absorbed by the heat pipe 145 and transferred to the metal block 155 side by the heat pipe 145. The heat transferred to the end of the heat pipe 145 on the metal block 155 side is transferred to the metal block 155 through the protrusion 141 of the cooling plate 140, and the heat transferred to the metal block 155 is transferred locally to the housing 150. The heat transmitted locally to the housing 150 is transmitted to the coolant via the refrigerant pipe 160. The heat transmitted to the cooling liquid is transferred to the radiator 13 (see FIG. 8) of the cooling system as the cooling liquid flows through the refrigerant flow path 160i. Thus, since the heat generated in the single battery cell 101 is transferred to the outside of the assembled battery 100 by the cooling structure, each single battery cell 101 is effectively cooled.

  FIG. 8 is a diagram illustrating a configuration of the cooling system. Heat transmitted from each single battery cell 101 to the coolant is dissipated by the radiator 13 of the cooling system. A cooling system is comprised including the pump 11, the tank 12, the radiator 13, and the piping 14 which connects them. The refrigerant pipe 160 of the power storage module 10 is provided on the pump discharge side of the cooling system, and the pipe 14 is connected to the refrigerant inlet portion 161 and the refrigerant outlet portion 162. The pump 11 circulates the coolant in the cooling system. The radiator 13 cools the cooling liquid heated by taking heat generated in each battery cell 101 constituting the power storage module 10 by exchanging heat with the atmosphere. The tank 12 has a role of a buffer for temporarily storing the coolant, and absorbs a change in the volume of the coolant due to a temperature change and stably supplies the coolant to the pump 11.

According to this embodiment described above, the following operational effects can be achieved.
(1) The battery pack 100 and the cooling structure 190 are housed inside, and the housing 150 to which the refrigerant pipe 160 is attached is provided, and each of the plurality of unit cells 101 is thermally coupled to the upper surface of the cooling plate 140. The heat pipe 145 is thermally coupled to the lower surface of the cooling plate 140, and the heat radiating portion 145c of the heat pipe 145 and the refrigerant pipe 160 are thermally coupled via the cooling plate 140, the metal block 155, and the housing 150. . As described above, in the present embodiment, the refrigerant pipe 160 is not provided in the casing 150, and the connection portion between the refrigerant pipe 160 and the cooling system pipe 14 does not exist in the casing 150. Further, it is possible to prevent the coolant from leaking into the housing 150 when an impact or vibration is applied to the power storage module 10.

  (2) Since it is not necessary to arrange the refrigerant pipe 160 in the housing 150, the power storage module 10 can be made compact, light, and low in cost.

  (3) Since the heat pipe 145 is thermally coupled to the cooling plate 140, the thickness of the cooling plate 140 can be reduced. Since the refrigerant pipe is inserted inside the cooling plate described in Patent Document 1, the thickness of the cooling plate is thicker than that of the present embodiment. On the other hand, according to the present embodiment, the vertical dimension (Z direction) of the power storage module 10 can be shortened, so that the power storage module 10 can be made compact, light, and low in cost. .

  (4) The heat pipe 145 absorbs the heat generated in each single battery cell 101, and the heat transported by the heat pipe 145 is transmitted to the refrigerant pipe 160 through the cooling plate 140, the metal block 155, and the housing 150, The cooling fluid flowing through the refrigerant flow path 160i of the refrigerant pipe 160 is transferred to the outside. Thereby, each of the plurality of single battery cells 101 can be effectively cooled without introducing the coolant into the housing 150.

  (5) The housing contact surface 190 a of the cooling structure 190 and the refrigerant pipe 160 are arranged to face each other with the housing 150 therebetween. As a result, the heat transmitted locally to the housing 150 is suppressed from spreading to the surroundings, and the heat can be efficiently transferred from the cooling structure 190 to the refrigerant pipe 160 via the housing 150.

-Second Embodiment-
A power storage module 20 according to the second embodiment will be described with reference to FIGS. 9 and 10. FIG. 9 is a schematic cross-sectional view of a power storage module 20 according to the second embodiment of the present invention, and FIG. 10 is a schematic plan view of the power storage module 20 according to the second embodiment of the present invention. In the figure, the same or corresponding parts as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. Hereinafter, differences from the first embodiment will be described in detail.

  In the first embodiment, the housing contact surface 190 a of the cooling structure 190 that contacts the housing 150 is provided on the metal block 155, and heat is passed through the cooling plate 140, the metal block 155, and the housing 150. The heat radiating portion 145c of the pipe 145 and the refrigerant pipe 160 were thermally coupled. In the second embodiment, as shown in FIGS. 9 and 10, the housing contact surface 290a of the cooling structure 290 that contacts the housing 150 is provided on the cooling plate 240, and the cooling plate 240 and The heat radiating portion 145c of the heat pipe 145 and the refrigerant pipe 160 are thermally coupled via the housing 150.

  The cooling plate 240 includes a coupling portion 240b that is thermally coupled to the bottom surface 102e of each single battery cell 101 via a thermal conductive sheet 189, and a bent portion that is bent at a right angle upward from one end of the coupling portion 240b. Part 240a. The bent portion 240 a is provided with a housing contact surface 290 a that contacts the inner surface of the housing 150. The housing contact surface 290a and the refrigerant pipe 160 are arranged to face each other with the housing 150 therebetween.

  The cooling plate 240 is welded in a state where the housing contact surface 290 a is in contact with the inner surface of the housing 150. As shown in FIG. 10, the housing contact surface 290a extends in the Y direction, and a sufficient contact area is ensured.

  According to the power storage module 20 of the second embodiment, the same effects as those of the first embodiment are obtained.

-Third embodiment-
A power storage module 30 according to the third embodiment will be described with reference to FIGS. 11 and 12. FIG. 11 is a schematic cross-sectional view of a power storage module 30 according to the third embodiment of the present invention, and FIG. 12 is a schematic plan view of the power storage module 30 according to the third embodiment of the present invention. In the figure, the same or corresponding parts as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. Hereinafter, differences from the first embodiment will be described in detail.

  In the third embodiment, as shown in FIGS. 11 and 12, the housing contact surface 390a of the cooling structure 390 that contacts the housing 150 is provided in the heat pipe 345, and the heat pipe 345 is Directly connected to the housing 150, the heat radiating portion 345 c of the heat pipe 345 and the refrigerant pipe 160 are thermally coupled via the housing 150.

  The heat pipe 345 includes a plate coupling portion 345b that is thermally coupled to the cooling plate 140, and a heat radiating portion 345c that is bent at a right angle in the Y direction from one end of the plate coupling portion 345b. The heat radiation part 345c is provided with a housing contact surface 390a that contacts the inner surface of the housing 150. The housing contact surface 390a and the refrigerant pipe 160 are arranged to face each other with the housing 150 therebetween.

  The heat pipe 345 is connected by soldering or the like with the housing contact surface 390 a in contact with the inner surface of the housing 150. As shown in FIG. 12, the heat radiating part 345c thermally coupled to the housing 150 extends in the Y direction, and a sufficient contact area is ensured.

  According to the power storage module 30 of the third embodiment, the same effects as those of the first embodiment are obtained.

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.
[Modification]
(1) In the above-described embodiment, the refrigerant pipe 160 is a cylindrical pipe having a circular cross section, but the present invention is not limited to this. It may be a hollow cylindrical tube having a rectangular cross section, a polygonal cross section, or a flat cross section. Further, the present invention is not limited to the case where the refrigerant pipe 160 attached to the housing 150 is a straight pipe. Furthermore, the present invention is not limited to the case where a single refrigerant pipe 160 is provided, and a plurality of refrigerant pipes 160 may be provided.

  (2) In the above-described embodiment, the power storage modules 10, 20, and 30 in which the single assembled battery 100 is accommodated in the housing 150 have been described. However, the present invention is not limited to this. You may apply this invention to the electrical storage module which accommodated the some assembled battery 100 in the housing | casing 150. FIG.

  (3) In the above embodiment, the cooling plate 140 is described as a single rectangular flat plate, but the present invention is not limited to this. For example, as shown in FIG. 13, the cooling plate 440 may be formed in a hollow rectangular parallelepiped shape, and a plurality of heat pipes (not shown) may be accommodated therein. Thereby, the single battery cell 101 can be arrange | positioned to each of a pair of surface where the cooling plate 440 opposes so that it may show in figure.

  (4) The layout of the single battery cells 101 with respect to the cooling plate is not limited to the above-described embodiment. For example, as shown in FIG. 14, a plurality of single battery cells 101 are arranged in three stages in the Y direction and in four stages in the X direction along each pair of opposing surfaces of the cooling plate 540. May be. In FIG. 14, each single battery cell 101 is arranged in a direction different by 90 ° from the case of the above-described embodiment. That is, according to the present invention, the single battery cells 101 can be arranged in various layouts with respect to the cooling plate.

  (5) Although the case where two heat pipes 145 and 345 are provided has been described in the above-described embodiment, the present invention is not limited to this. Depending on the capacity and number of unit cells 101, three or more may be provided, or one heat pipe may be provided.

  (6) In the above-described embodiment, the structure in which the cooling plates 140 and 240 are thermally coupled to the bottom surface 102e of the single battery cell 101 has been described, but the present invention is not limited to this. A structure in which a cooling plate is thermally coupled to the narrow surface 102d of each single battery cell 101 may be employed.

(7) In the above-described embodiment, the case where the coolant is employed as the refrigerant has been described, but the present invention is not limited to this. Cooling air may be circulated through the refrigerant flow path 160i of the refrigerant pipe 160.
(8) The refrigerant flow path forming body is not limited to a pipe. For example, a heat sink or the like provided with a refrigerant flow path for circulating cooling air between the cooling fins may be adopted as the refrigerant flow path forming body.

  (9) In the above-described embodiment, the shape of the battery container is a square, but the present invention is not limited to this. A flat battery container having an oval cross section may be used, and various thin battery containers in which the opening of the battery can is sealed with a battery lid can be employed.

  (10) Although the lithium ion secondary battery has been described as an example, the present invention can also be applied to other secondary batteries such as a nickel metal hydride battery.

  (11) The materials of the positive electrode external terminal 104, the positive electrode current collector (not shown), and the positive electrode foil 171 are not limited to aluminum, and may be an aluminum alloy. The material of the negative electrode external terminal 105, the negative electrode current collector (not shown), and the negative electrode foil 172 is not limited to copper, and may be a copper alloy.

  (12) The material of the housing 150, the refrigerant pipe 160, the cooling plates 140 and 240, and the metal block 155 is not limited to aluminum. Various materials having good thermal conductivity such as aluminum alloys, metals such as copper and stainless steel, or insulating resins having a thermal conductivity of 1 W / m · K or more can be used.

  (13) In the above-described embodiment, the bottom surface 102e of the single battery cell 101 and the cooling plates 140 and 240 are brought into close contact with each other via the thermal conductive sheet 189, but the present invention is not limited to this. When the battery container of the single battery cell 101 has insulation, the bottom surface 102e of the battery container of the single battery cell 101 may be brought into close contact with the cooling plates 140 and 240 directly.

  (14) In the first embodiment, the heat radiation part 145c of the heat pipe 145 and the refrigerant pipe 160 are thermally coupled via the cooling plate 140, the metal block 155, and the housing 150. In the second embodiment, the heat radiating portion 145 c of the heat pipe 145 and the refrigerant pipe 160 are thermally coupled via the cooling plate 240 and the housing 150. In the third embodiment, the heat pipe 345 is directly thermally coupled to the housing 150, and the heat radiating portion 345c of the heat pipe 345 and the refrigerant pipe 160 are thermally coupled only through the housing 150. . However, the present invention is not limited to this, and various cooling structures that can thermally couple the heat radiation portions 145c and 345c of the heat pipes 145 and 345 and the refrigerant pipe 160 through at least the housing 150 are employed. be able to. In other words, the heat radiating portions 145c and 345c of the heat pipes 145 and 345 and the housing 150 may be directly or indirectly thermally coupled.

  The present invention is not limited to the embodiment described above, and can be freely changed and improved without departing from the gist of the invention.

DESCRIPTION OF SYMBOLS 10 Storage module, 11 Pump 12 Tank, 13 Radiator, 14 Piping, 20 Storage module, 30 Storage module, 100 Assembly battery, 101 Single battery cell, 102A Battery can, 102B Battery cover, 102c Main surface, 102d Narrow surface, 102e Bottom surface, 103 Gas discharge valve, 104 Positive external terminal, 105 Negative external terminal, 106 Gasket, 107 Injection part, 109 Bus bar, 110 Gas exhaust duct, 119 Joint part, 120A, 120B End plate, 125 Battery holder, 130 Shaft, 131 nut, 140 cooling plate, 141 projecting portion, 145 heat pipe, 145c heat radiating portion, 145P flat surface portion, 150 housing, 155 metal block, 160 refrigerant pipe, 160i refrigerant flow path, 161 refrigerant inlet portion, 162 refrigerant outlet portion, 170 Rotating 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, 189 heat conductive sheet, 190 cooling structure, 190a housing contact surface, 240 cooling plate, 240a bent portion, 240b coupling portion, 290 cooling structure, 290a housing contact surface, 345 heat pipe, 345b plate coupling portion, 345c heat dissipation portion, 390 cooling structure, 390a Housing contact surface, 440 cooling plate, 540 cooling plate

Claims (7)

An assembled battery in which a plurality of unit cells are electrically connected;
A cooling structure including a cooling plate and a heat pipe having a heat radiating portion on one end side;
A refrigerant flow path forming body having a refrigerant flow path through which the refrigerant flows;
A housing in which the assembled battery and the cooling structure are housed, and the refrigerant flow path forming body is attached to the outside;
Each of the plurality of unit cells is thermally coupled to one surface of the cooling plate, the heat pipe is thermally coupled to the other surface of the cooling plate, and at least the heat is transmitted through the housing. A heat storage module, wherein a heat radiating portion of a pipe and the refrigerant flow path forming body are thermally coupled. The power storage module according to claim 1,
The cooling structure has an abutting surface that abuts on the housing,
The power storage module, wherein the refrigerant flow path forming body and the contact surface of the cooling structure are arranged to face each other with the housing therebetween. The power storage module according to claim 2,
The unit cell is provided with a positive external terminal and a negative external terminal electrically connected to the charge / discharge element on one surface of a rectangular battery container that houses the charge / discharge element,
The unit cell is a power storage module, wherein the other surface of the battery container facing the one surface is in close contact with one surface of the cooling plate. In the electrical storage module of Claim 2 or 3,
The heat radiating part of the heat pipe is thermally coupled to the other surface of the cooling plate,
A heat transfer member disposed to face the heat radiating part of the heat pipe via the cooling plate, and further thermally coupled to one surface of the cooling plate;
The contact surface of the cooling structure is provided on the heat transfer member,
A power storage module, wherein a heat radiating portion of the heat pipe and the refrigerant flow path forming body are thermally coupled to each other through the cooling plate, the heat transfer member, and the housing. In the electrical storage module of Claim 2 or 3,
The heat radiating part of the heat pipe is thermally coupled to the other surface of the cooling plate,
The contact surface of the cooling structure is provided on the cooling plate,
A power storage module, wherein a heat radiating portion of the heat pipe and the refrigerant flow path forming body are thermally coupled via the cooling plate and the housing. In the electrical storage module of Claim 2 or 3,
The heat pipe includes a plate coupling portion that is thermally coupled to the cooling plate, and a housing coupling portion that is thermally coupled to the housing.
The contact surface of the cooling structure is provided in a housing coupling portion of the heat pipe. The power storage module according to any one of claims 1 to 3,
The power storage module, wherein the coolant channel forming body is a metal tube.

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