Battery unit

A battery unit includes at least one battery module, a cooling device configured to deliver a cooling gas configured to cool the battery module to the battery module, and a junction board mounted with a wiring component configured to electrically connect the battery module and an external device and allow a charging power and/or a discharging power of the battery module to flow. The junction board is disposed above the cooling device at a position where at least a part of the junction board overlaps the cooling device when viewed from an upper-lower direction.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based on and claims priority under 35 USC 119 from Japanese Patent Application No. 2021-121045 filed on Jul. 21, 2021.

TECHNICAL FIELD

The present disclosure relates to a battery unit. In particular, the present disclosure relates to a battery unit mounted on a vehicle.

BACKGROUND ART

In recent years, as a specific measure against global climate change, efforts for realizing a low-carbon society or a decarbonized society have become active. Also in a vehicle, a CO2emission is strongly required to be reduced, and electrification of a drive source is progressing rapidly. Specifically, a vehicle, such as an electrical vehicle or a hybrid electrical vehicle, including an electric motor as a drive source for the vehicle and a battery as a secondary battery capable of supplying a power to the electric motor is being developed.

Along with the electrification of the drive source of the vehicle, a high-capacity battery unit is mounted on the vehicle. Since the high-capacity battery unit has a large amount of heat generation, higher cooling performance is required.

JP-A-2018-190660 discloses a battery unit provided in an installation space under, for example, a seat of a hybrid vehicle. In the battery unit of JP-A-2018-190660, a first fan, a second fan, and a control unit are provided adjacent to each other in a vertical direction of a battery module. The control unit is disposed between the first fan and the second fan, and the first fan and the second fan function as exhaust fans which discharge a cooling gas which has cooled the battery module toward an outside in the vertical direction.

However, there is a problem that since the battery unit of JP-A-2018-190660 has the installation space under the seat, air which is heated by heat generated in the control unit stays between the seat and an upper surface of the battery module, and the air which is heated by the heat generated in the control unit is supplied to the battery module by the first fan and the second fan as a part of the cooling gas for cooling the battery module, and thus the cooling performance is decreased. Meanwhile, in the battery unit of JP-A-2018-190660, also in a case where in order to supply the cooling gas to the battery module more reliably, the first fan and the second fan are used as intake fans, and the cooling gas exhausted from the first fan and the second fan is supplied to the battery module, there is a problem that the heat generated by the control unit is delivered to the first fan and the second fan, and a temperature of the cooling gas supplied to the battery module rises.

SUMMARY OF INVENTION

The present disclosure provides a battery unit capable of supplying a lower-temperature cooling gas to a battery module and having an improved cooling performance.

According to an aspect of the present disclosure, there is provided a battery unit, including:at least one battery module;a cooling device configured to deliver a cooling gas configured to cool the battery module to the battery module; anda junction board mounted with a wiring component configured to electrically connect the battery module and an external device and allow a charging power and/or a discharging power of the battery module to flow, in which:the junction board is disposed above the cooling device at a position where at least a part of the junction board overlaps the cooling device when viewed from an upper-lower direction.

According to the present disclosure, the heat generated in the junction board can be prevented from being transferred to the cooling device, and thus the cooling gas supplied from the cooling device to the battery module can be prevented from rising in temperature due to the heat generated in the junction board. Accordingly, a lower-temperature cooling gas can be supplied to the battery module, and a cooling performance of the battery unit is improved.

DESCRIPTION OF EMBODIMENTS

Hereinafter, an embodiment of a battery unit of the present disclosure will be described with reference to accompanying drawings. In the present embodiment, the battery unit is mounted on a vehicle. It should be noted that the drawings are viewed in direction of reference numerals. In the present specification and the like, in order to simplify and clarify the description, a front-rear direction, a left-right direction, and an upper-lower direction are described in accordance with directions viewed from a driver of a vehicle. In the drawings, a front side of the vehicle is denoted by Fr, a rear side thereof is denoted by Rr, a left side thereof is denoted by L, a right side thereof is denoted by R, an upper side thereof is denoted by U, and a lower side thereof is denoted by D.

As illustrated inFIGS.1and2, a battery unit20of the present embodiment is mounted on a vehicle V. The vehicle V is, for example, an electric vehicle, such as a hybrid vehicle or a battery-powered vehicle, equipped with a drive electric motor (not illustrated) capable of driving the vehicle V by a power stored in the battery unit20. The battery unit20is mounted on a floor panel10and fixed to the floor panel10. A rear seat RS of the vehicle V is disposed above the battery unit20.

The floor panel10includes a front floor panel11which constitutes a floor portion of a vehicle cabin CB, and a rear floor panel12which constitutes a floor portion and the like of a luggage compartment LG provided behind the vehicle cabin CB. The front floor panel11and the rear floor panel12are connected below the rear seat RS. Two end portions of the floor panel10in a vehicle width direction are connected to a pair of left and right skeletal frame members (not illustrated) which extend along the front-rear direction. Accordingly, the floor panel10is fixed to the skeletal frame members.

A kick-up portion11awhich rises upward is formed at a rear end portion of the front floor panel11. A center tunnel11bis formed along the front-rear direction at a central portion of the front floor panel11in the vehicle width direction. The center tunnel11bis bent such that the front floor panel11protrudes upward. A trapezoidal tunnel space13is formed below the center tunnel11b.

An accommodation recessed portion121is formed at a front end portion of the rear floor panel12. The accommodation recessed portion121includes a rectangular bottom wall portion121awhich is long in the vehicle width direction, and the battery unit20is mounted on the bottom wall portion121a.

As illustrated inFIGS.1to5, the battery unit20includes two battery modules30, a cooling device40through which a cooling gas for cooling the battery modules30flows, a battery control device51which controls charging and discharging of the battery modules30, a junction board52which is equipped with a wiring component which electrically connects the battery modules30and an external device (not illustrated) and allows a charging power and a discharging power of the battery module30to flow, and a service plug53which is capable of cutting off the powers flowing through the junction board52.

The battery unit20includes a base plate60on which the two battery modules30are mounted, and a front frame81and a rear frame82which cover a bottom of the base plate60and are fixed to the base plate60. The base plate60is mounted on the bottom wall portion121aof the accommodation recessed portion121recessed in the front end portion of the rear floor panel12.

The battery module30has a substantially rectangular parallelepiped shape which is long in the vehicle width direction. The two battery modules30are arranged so as to face each other in the front-rear direction. Each battery module30has a plurality of battery cells31stacked in the vehicle width direction. The battery cell31has a substantially rectangular parallelepiped shape which is shortest in the vehicle width direction.

The cooling device40, the junction board52, and the service plug53are disposed on a right side of the battery module30. The cooling device40and the junction board52are provided at a position where at least a part of each of the cooling device40and the junction board52overlaps the battery modules30when viewed from the vehicle width direction.

Accordingly, the cooling device40and the junction board52can be disposed in the battery unit20while reducing a front-rear direction dimension and a height dimension of the battery unit20.

The cooling device40includes a fan41which blows the cooling gas for cooling the battery modules30, an introduction duct42which introduces the cooling gas into the fan41, and a delivery duct43which delivers the cooling gas blown from the fan41in a desired direction.

The fan41is mounted on the base plate60. The fan41is provided at a position where at least a part of the fan41overlaps the battery modules30when viewed from the vehicle width direction. The fan41includes an impeller41awhich aspirates the cooling gas from a rotation axis direction and blows the cooling gas in a centrifugal direction, and a fan case41bwhich pivotably supports and accommodates the impeller41a. The fan case41bincludes an aspiration port41cwhich aspirates the cooling gas supplied to the impeller41a, and an outlet41dwhich discharges the cooling gas blown from the impeller41a. In the present embodiment, a rotation axis of the impeller41aextends in the upper-lower direction. The fan case41bhas a substantially cylindrical shape which extends in the upper-lower direction. The aspiration port41copens upward. The outlet41dprotrudes to a left side from the fan case41bhaving the substantially cylindrical shape, and opens to the left side. Therefore, the fan41aspirates the upper side cooling gas through the aspiration port41cand delivers the cooling gas through the outlet41dto the left side.

The introduction duct42is disposed on an upper side of the fan41. The introduction duct42is provided adjacent to an upper part of the fan41and covers the upper part of the fan41. The introduction duct42is provided at a position where at least a part of the introduction duct42overlaps the battery modules30when viewed from the vehicle width direction. A flow path42athrough which the cooling gas flows is formed in the introduction duct42. An introduction port42bwhich opens diagonally upward and forward is provided on one end side of the flow path42a. A discharge port42cwhich opens downward and is connected to the aspiration port41cof the fan case41bis provided on the other end side of the flow path42a. In the introduction duct42, the cooling gas for cooling the battery modules30is introduced into the flow path42afrom the introduction port42b, flows through the flow path42a, and is aspirated into the aspiration port41cof the fan41through the discharge port42c.

A pair of front and rear positioning pins42dwhich project downward in a substantially columnar shape are provided at a left end portion of the introduction duct42. The positioning pin42dhas a substantially cylindrical shape with a tapered tip.

The delivery duct43is provided adjacent to a left side of the fan41and is connected to the outlet41dof the fan case41b. The delivery duct43delivers the cooling gas blown from the outlet41dof the fan case41btoward the left side along lower surfaces of the battery modules30. Details of the delivery duct43will be described later.

The battery control device51has a substantially rectangular parallelepiped shape which is shortest in the upper-lower direction, and is arranged at a position facing upper surfaces of the battery modules30so as to straddle the two battery modules30arranged in the front-rear direction.

The junction board52has a substantially rectangular parallelepiped shape which is shortest in the upper-lower direction, and is disposed above the cooling device40at a position where at least a part of the junction board52overlaps the cooling device40when viewed from the upper-lower direction. Therefore, the introduction duct42of the cooling device40is disposed between the junction board52and the fan41in the upper-lower direction. The junction board52is provided at a position where at least a part of the junction board52overlaps the battery modules30when viewed from the vehicle width direction.

The service plug53is provided on a wiring member which electrically connects the external device (not illustrated) and the junction board52, and is a plug which can be manually inserted and removed. When the service plug53is inserted, the external device (not illustrated) and the junction board52are electrically connected, and when the service plug53is removed, the external device (not illustrated) and the junction board52are electrically isolated. The service plug53is disposed in front of the junction board52. The service plug53is provided at a position where at least a part of the service plug53overlaps the junction board52when viewed from the front-rear direction.

As illustrated inFIGS.3to5, the base plate60includes a bottom wall portion61which covers bottoms of the two battery modules30and the cooling device40disposed on a right side of the battery module30, and a side wall portion62which bends upward from front, rear, left, and right outer edge portions of the bottom wall portion61, surrounds the front, rear, left, and right outer edge portions of the bottom wall portion61, and extends in the upper-lower direction. The side wall portion62includes a front wall portion62awhich is bent upward from an front edge portion of the bottom wall portion61, a rear wall portion62bwhich is bent upward from a rear edge portion of the bottom wall portion61, a left wall portion62cwhich is bent upward from a left edge portion of the bottom wall portion61, and a right wall portion62dwhich is bent upward from a right edge portion of the bottom wall portion61.

The base plate60further includes a sealing member63fixed to an upper surface of the bottom wall portion61and extending in the vehicle width direction. The sealing member63is formed of a material which is impermeable to a gas. In the present embodiment, the sealing member63is formed of a rubber foam having adhesive layers formed on an upper surface and a lower surface. The adhesive layer formed on the lower surface of the sealing member63adheres to the upper surface of the bottom wall portion61of the base plate60, whereby the sealing member63is fixed to the upper surface of the bottom wall portion61so as not to form a gap between the sealing member63and the upper surface of the bottom wall portion61. The sealing member63includes a pair of left and right side sealing members63awhich extend in the front-rear direction, a front sealing member63bwhich connects front end portions of the pair of left and right side sealing members63aand extends in the vehicle width direction, a rear sealing member63cwhich connects the front end portions of the pair of left and right side sealing members63aand extends in the vehicle width direction, and a central sealing member63dwhich connects substantially central portions in the front-rear direction of the pair of left and right side sealing members63aand extends in the vehicle width direction. The pair of left and right side sealing members63aare located at substantially the same position as left end portions and right end portions of the battery modules30in the left-right direction, and each extend in the front-rear direction from substantially the same position as the front end portion of the battery module30arranged in the front side to substantially the same position as the rear end portion of the battery module30arranged in the rear side. The front sealing member63b, the rear sealing member63c, and the central sealing member63dare extended in the vehicle width direction from substantially the same position as the left end portion of the battery module30to substantially the same position as the right end portion of the battery module30in the left-right direction, respectively.

The two battery modules30are mounted on the sealing member63. In the two battery modules30, the battery module30arranged on the front side is mounted such that the front end portion is supported by the front sealing member63bof the sealing member63and a rear end portion is supported by the central sealing member63dof the sealing member63. Then, the front sealing member63band the central sealing member63dare compressed by a weight of the battery module30arranged on the front side, and the adhesive layers formed on the upper surfaces of the front sealing member63band the central sealing member63dadhere to the lower surface of the battery module30arranged in the front side, whereby the battery module30arranged in the front side is fixed to the upper surfaces of the front sealing member63band the central sealing member63dso as not to form a gap between the battery module30and the upper surfaces of the front sealing member63band the central sealing member63d. In the two battery modules30, the battery module30arranged in the rear side is mounted such that a front end portion is supported by the central sealing member63dof the sealing member63and the rear end portion is supported by the rear sealing member63cof the sealing member63. Then, the central sealing member63dand the rear sealing member63care compressed by a weight of the battery module30arranged on the rear side, and the adhesive layers formed on the upper surfaces of the central sealing member63dand the rear sealing member63cadhere to the lower surface of the battery module30arranged in the rear side, whereby the battery module30arranged in the rear side is fixed to the upper surfaces of the central sealing member63dand the rear sealing member63cso as not to form a gap between the battery module30and the upper surfaces of the central sealing member63dand the rear sealing member63c. Accordingly, a flow path60athrough which the cooling gas for cooling the battery module30flows is formed between the lower surface of the battery module30and the bottom wall portion61of the base plate60with the sealing member63interposed therebetween. In the present embodiment, two flow paths60aare formed. One flow path60ais surrounded by the lower surface of the battery module30arranged on the front side, the bottom wall portion61of the base plate60, the pair of left and right side sealing members63a, the front sealing member63b, and the central sealing member63d, and the other flow path60ais surrounded by the lower surface of the battery module30arranged in the rear side, the bottom wall portion61of the base plate60, the pair of left and right side sealing members63a, the central sealing member63d, and the rear sealing member63c. The lower surface of the battery module30arranged on the front side and the bottom wall portion61of the base plate60are fixed to the sealing member63, which is impermeable to a gas, without any gap, and the lower surface of the battery module30arranged in the rear side and the bottom wall portion61of the base plate60are fixed to the sealing member63, which is impermeable to a gas, without any gap, so that the gas flowing through the two flow paths60adoes not leak to outsides of the flow paths60afrom the lower surfaces of the battery modules30and the bottom wall portion61of the base plate60.

The base plate60further includes a plate-shaped support member64fixed to the upper surface of the bottom wall portion61and extending in the front-rear direction. The support member64has a main surface64awhich extends in the front-rear direction and the vehicle width direction, a side wall portion64bwhich bends downward from a front edge portion, a rear edge portion, and a left edge portion of the main surface64aand extends in the upper-lower direction around the front edge portion, the rear edge portion, and the left edge portion of the main surface64a, and a flange portion64cwhich extends in a flange shape from a lower end portion of the side wall portion64b. Therefore, the side wall portion64band the flange portion64chave a U-shape which opens to the right when viewed from the upper-lower direction. A lower surface of the flange portion64cis in contact with the bottom wall portion61of the base plate60and is fixed to the bottom wall portion61. The support member64is provided such that the right side sealing member63aof the sealing member63is disposed on an upper surface of the flange portion64cof a portion extending to a left side of the left edge portion of the main surface64a. That is, the support member64is sandwiched in the upper-lower direction by the bottom wall portion61and a right side sealing member63aof the sealing member63at the flange portion64cof the portion extending to the left side of the left edge portion of the main surface64a. Then, the adhesive layer formed on the lower surface of the right side sealing member63aadheres to the upper surface of the flange portion64cof the portion extending to the left side of the left edge portion of the main surface64a.

A flow path connection space60bsurrounded by the lower surface of the support member64and the bottom wall portion61is formed between the lower surface of the support member64and the bottom wall portion61. The flow path connection space60bhas a shape which bulges upward from the flange portion64cof the support member64toward the main surface64a. As described above, since the support member64is provided such that the right side sealing member63aof the sealing member63is disposed on the upper surface of the flange portion64cof the portion extending to the left side of the left edge portion of the main surface64a, the flow path connection space60bis continuous with the flow paths60aformed between the lower surfaces of the battery modules30and the bottom wall portion61of the base plate60. Accordingly, the support member64is provided such that the flow path connection space60bsurrounded by the lower surface of the support member64and the bottom wall portion61is continuous with the flow paths60aformed between the lower surfaces of the battery modules30and the bottom wall portion61of the base plate60. Since the adhesive layer formed on the lower surface of the right side sealing member63aadheres to the upper surface of the flange portion64cof the portion extending to the left side of the left edge portion of the main surface64a, the gas flowing through the flow path connection space60bflows to the flow paths60awithout leaking.

A front frame81is connected to the base plate60and extends in the vehicle width direction to cover the front wall portion62aof the base plate60. A rear frame82is connected to the base plate60and extends in the vehicle width direction to cover the rear wall portion62bof the base plate60. The front frame81is fixed to the floor panel10of the vehicle V, more specifically, to the kick-up portion11aof the front floor panel11by a fastening member such as a bolt. The rear frame82is fixed to the floor panel10of the vehicle V, more specifically, to the front end portion of the rear floor panel12by a fastening member such as a bolt (seeFIG.2).

A protrusion82awhich protrudes forward is formed at a right end portion of the rear frame82. The protrusion82ahas a flat plate shape which extends in a substantially horizontal direction from a right rear end portion toward the front of the rear frame82. The protrusion82ais provided with a substantially columnar male screw pin82bwhich is inserted through the protrusion82ain the upper-lower direction and protrudes upward. An outer peripheral surface of the male screw pin82bis male-threaded.

As illustrated inFIGS.3to5,7, and9, the base plate60includes a left battery module mounting portion65which protrudes to the right side from the left wall portion62c. The left battery module mounting portion65is provided with a pair of front and rear male screw pins65awhich have a substantially columnar shape, are inserted in the upper-lower direction, and protrude upward. An outer peripheral surface of each male screw pin65ais male-threaded. A left battery module bracket71is fixed to the left battery module mounting portion65.

When viewed from the vehicle width direction, at a position overlapping left side surfaces of the two battery modules30arranged in the front-rear direction, the left battery module bracket71includes a main plate71awhich extends in the front-rear direction and the upper-lower direction, an upper end portion71bwhich bends to the right direction from an upper end of the main plate71a, extends in the front-rear direction and to the right direction from the upper end of the main plate71a, and faces the left end portions of the upper surfaces of the two battery modules30arranged in the front-rear direction, and a lower end portion71cwhich bends to the left direction from a lower end of the main plate71a, extends in the front-rear direction and to the left direction from the lower end of the main plate71a, and faces the left battery module mounting portion65.

At positions overlapping the pair of front and rear male screw pins65aprovided on the left battery module mounting portion65, the lower end portion71cof the left battery module bracket71is formed with a pair of front and rear insertion holes through which the male screw pins65aare respectively inserted. In the left battery module bracket71, the pair of front and rear male screw pins65aof the left battery module mounting portion65are inserted into the pair of front and rear insertion holes formed in the lower end portion71c, and a fastening member such as a nut is fastened to each of the male screw pins65afrom above, so that the lower end portion71cis fixed to the left battery module mounting portion65. In this way, the left battery module bracket71has the lower end portion71cfixed to the left battery module mounting portion65, and extends in the upper-lower direction.

Two substantially cylindrical male screw pins30awhich project to the left side are provided in the front-rear direction on the left side surfaces of the two battery modules30arranged in the front-rear direction. At positions overlapping the male screw pins30awhich protrude to the left from the left side surfaces of the two battery modules30, the main plate71aof the left battery module bracket71is formed with the insertion holes through which the male screw pins30aare respectively inserted. The male screw pins30aprovided on the left side surfaces of the two battery modules30are inserted into the insertion holes formed in the main plate71aof the left battery module bracket71, and the fastening member such as a nut is fastened to each of the male screw pins30afrom the left, so that the left battery module bracket71supports, from the left side, the left side surfaces of the two battery modules30arranged in the front-rear direction.

The main surface64aof the support member64is provided with a pair of front and rear male screw pins64dwhich have a substantially columnar shape, are inserted through the main surface64ain the upper-lower direction, and protrude upward. An outer peripheral surface of each male screw pin64dis male-threaded.

A right battery module bracket72is fixed to the support member64. When viewed from the vehicle width direction, at a position overlapping right side surfaces of the two battery modules30arranged in the front-rear direction, the right battery module bracket72includes a main plate72awhich extends in the front-rear direction and the upper-lower direction, an upper end portion72bwhich bends to the left direction from an upper end of the main plate72a, extends in the front-rear direction and to the left direction from an upper end of the main plate72a, and faces the right end portions of the upper surfaces of the two battery modules30arranged in the front-rear direction, and a lower end portion72cwhich bends to the left direction from a lower end of the main plate72a, extends in the front-rear direction and to the left direction from the lower end of the main plate72a, and faces the main surface64aof the support member64.

At positions overlapping the pair of front and rear male screw pins64dprovided on the main surface64aof the support member64, the lower end portion72cof the right battery module bracket72is formed with a pair of front and rear insertion holes through which the male screw pins64dare inserted. In the right battery module bracket72, the pair of front and rear male screw pins64dprovided on the main surface64aof the support member64are respectively inserted into the pair of front and rear insertion holes formed in the lower end portion72c, and a fastening member64esuch as a nut is fastened to each of the male screw pins64dfrom above, so that the lower end portion72cis fixed to the main surface64aof the support member64. In this way, the right battery module bracket72has the lower end portion72cfixed to the support member64, and extends in the upper-lower direction. In the present embodiment, the fastening member64eis a nut which can be screwed into the male screw pin64d.

Two substantially columnar male screw pins30bwhich protrudes to the right are provided in the front-rear direction on the right side surfaces of the two battery modules30arranged in the front-rear direction. At positions overlapping the male screw pins30bwhich protrudes to the right from the right side surfaces of the two battery modules30, the main plate72aof the right battery module bracket72is formed with insertion holes through which the male screw pins30bare respectively inserted. The male screw pins30bprovided on the right side surfaces of the two battery modules30are respectively inserted into the insertion holes formed in the main plate72aof the right battery module bracket72, and a fastening member such as a nut is fastened to each of the male screw pins30bfrom the right, so that the right battery module bracket72supports the right side surfaces of the two battery modules30arranged in the front-rear direction from the right.

As illustrated inFIGS.4and5, the base plate60includes a first fan mounting portion66which protrudes to the left from the right wall portion62d. A first fan mounting portion66is provided with a pair of front and rear male screw pins66awhich have a substantially columnar shape, are inserted in the upper-lower direction, and protrude upward. An outer peripheral surface of each male screw pin66ais male-threaded.

The base plate60includes a second fan mounting portion67which protrudes forward from the rear wall portion62bbetween the first fan mounting portion66and the support member64in the vehicle width direction. The second fan mounting portion67is provided with one substantially columnar male screw pin67awhich is inserted in the upper-lower direction and protrudes upward in the present embodiment. An outer peripheral surface of the male screw pin67ais male-threaded.

The substantially cylindrical fan case41bextending in the upper-lower direction is provided with lug portions41ewhich protrude outward in a radial direction. In the present embodiment, the lug portions41eare provided at a right front region of the fan case41b, a right rear region of the fan case41b, and a left rear region of the fan case41b. Therefore, in the present embodiment, the fan case41bis provided with a total of three lug portions41e. Each of the lug portions41eis formed with an insertion hole which is penetrated in the upper-lower direction. The pair of front and rear male screw pins66aprovided on the first fan mounting portion66are inserted into the insertion holes from in the lug portions41eprovided at the right front region of the fan case41band the right rear region of the fan case41b, the male screw pin67aprovided on the second fan mounting portion67is inserted into the insertion hole formed in the lug portion41eprovided in the left rear region of the fan case41b, and the male screw pins66aand the male screw pin67aare fastened with fastening members such as nuts from above, so that the fan case41bis fixed to the first fan mounting portion66and the second fan mounting portion67of the base plate60. In this way, the fan41is fixed to the base plate60.

As illustrated inFIGS.6A and6B, the delivery duct43has an upper surface431, a front surface432, a rear surface433, a left surface434, and a right surface435. A lower part of the delivery duct43opens.

The delivery duct43includes an upper member43aand a lower member43b. The upper member43aforms the upper surface431, an upper region of the front surface432, an upper region of the rear surface433, an upper region of the left surface434, and an upper region of the right surface435of the delivery duct43. The lower member43bforms a lower region of the front surface432, a lower region of the rear surface433, a lower region of the left surface434, and a lower region of the right surface435of the delivery duct43. The delivery duct43is formed by connecting the upper member43aand the lower member43b. In the present embodiment, a plurality of locking claws protruding upward are provided at an upper end of the lower member43b, and the upper member43aand the lower member43bare connected by locking the locking claws to the upper member43a.

The delivery duct43is formed with a duct portion43csurrounded by the upper member43aand the lower member43b.

The left surface434of the delivery duct43is formed with an introduction port43dwhich protrudes at the diagonally forward left side in a rectangular cylindrical shape to communicate with the duct portion43c, has an opened protrusion end portion, and connects to the outlet41dformed in the fan case41bof the fan41. Accordingly, the cooling gas blown from the outlet41dof the fan41is introduced into the duct portion43cthrough the introduction port43d.

A lower edge portion432aof the front surface432, a lower edge portion433aof the rear surface433, and a lower edge portion435aof the right surface435of the delivery duct43have a shape which follows a shape of the bottom wall portion61of the base plate60. A lower edge portion434aof the left surface434of the delivery duct43includes a curved portion43ewhich is curved upward from the bottom wall portion61. The curved portion43ehas a shape along an upper surface of the support member64.

The delivery duct43has an opening43fwhose outer edge includes the lower edge portion432aof the front surface432, the lower edge portion433aof the rear surface433, the lower edge portion434aof the left surface434including the curved portion43e, and the lower edge portion435aof the right surface435. Therefore, the opening43fopens downward and to the left.

A sealing member43gis provided over an entire circumference of the front, back, left, and right of the outer edge of the opening43f, that is, the lower edge portion432aof the front surface432, the lower edge portion433aof the rear surface433, the lower edge portion434aof the left surface434including the curved portion43e, and the lower edge portion435aof the right surface435. The sealing member43gis formed of an elastic material such as rubber.

The upper surface431of the delivery duct43is provided with a pedestal portion43hwith which a lower surface of the introduction duct42is in contact. The pedestal portion43his provided at a left end portion of the upper member43aso as to extend in the front-rear direction. The upper member43ais provided with a pair of front and rear protrusions43iwhich protrude to the left from the pedestal portion43h.

A tip portion of each protrusion43iis provided with a first engaging portion43jwhich engages with the male screw pin64dprovided on the main surface64aof the support member64and the fastening member64efastened to the male screw pin64d. The first engaging portion43jhas a large diameter portion43kwhich protrudes in a hollow cylindrical shape from a lower surface of the tip portion of the protrusion43iand has an opened lower end. The large diameter portion43khas a hollow cylindrical shape to which the male screw pin64dprovided on the main surface64aof the support member64and the fastening member64efastened to the male screw pin64dcan be engaged.

The first engaging portion43jfurther includes a small diameter portion43mwhich has the same center as the large diameter portion43k, and penetrates at the tip portion of the protrusion43iin the upper-lower direction. The small diameter portion43mhas a hole shape through which the male screw pin64dprovided on the main surface64aof the support member64can be inserted and the fastening member64efastened to the male screw pin64dcannot be inserted.

Further, each protrusion43iis provided with a second engaging portion43nto which the positioning pin42dprovided at the left end portion of the introduction duct42engages. In the present embodiment, the second engaging portion43nis provided on a right side of the first engaging portion43jof the protrusion43i. The second engaging portion43nis a through hole which penetrates the protrusion43iin the upper-lower direction and through which the positioning pin42dof the introduction duct42can be inserted.

The delivery duct43is provided with a locking claw43pwhich locks to the outlet41dof the fan case41b. In the present embodiment, the locking claw43pis provided at the upper member43a.

As illustrated inFIGS.4to9, the locking claw43pof the delivery duct43locks to the outlet41dof the fan case41b, so that the delivery duct43is connected to the fan41, and the introduction port43dof the delivery duct43is connected to the outlet41dformed in the fan case41b.

The lower edge portion432aof the front surface432, the lower edge portion433aof the rear surface433, and the lower edge portion435aof the right surface435of the delivery duct43are in contact with the bottom wall portion61of the base plate60via the sealing member43g. The lower edge portion434aof the left surface434including the curved portion43eof the delivery duct43is in contact with the upper surface of the support member64via the sealing member43g. Therefore, the opening43fopens downward and toward the flow path connection space60bsurrounded by the lower surface of the support member64and the bottom wall portion61. The opening43fof the delivery duct43is sealed by the bottom wall portion61of the base plate60and the upper surface of the support member64of the base plate60via the sealing member43g.

In this case, the first engaging portion43jof the delivery duct43engages with the male screw pin64dprovided on the upper surface of the support member64and the fastening member64efastened to the male screw pin64d. Accordingly, the male screw pin64dprovided on the upper surface of the support member64and the fastening member64efastened to the male screw pin64dalso function as an engaged portion engaged with the first engaging portion43jof the delivery duct43.

Accordingly, when the delivery duct43is attached to the base plate60, the first engaging portion of the delivery duct43is engaged with the base plate60, so that the delivery duct43can be easily positioned with respect to the base plate60, and an assemblability of the battery unit20is improved.

Further, the male screw pin64dand the fastening member64efastened to the male screw pin64d, which function as the engaged portion engaged with the first engaging portion43jof the delivery duct43, are provided on the upper surface of the support member64. Accordingly, the delivery duct43can be attached to the base plate60from above, and when the delivery duct43is attached to the base plate60from above, a position of the engaged portion engaged with the first engaging portion43jof the delivery duct43can be easily confirmed, and thus the assemblability of the battery unit20is further improved.

In the fan41and the delivery duct43attached to the base plate60, the cooling gas blown from the outlet41dof the fan41and introduced into the duct portion43cthrough the introduction port43dis delivered through the opening43fof the delivery duct43to the flow path connection space60bsurrounded by the lower surface of the support member64and the bottom wall portion61. Accordingly, the delivery duct43delivers, to the flow path connection space60bsurrounded by the lower surface of the support member64and the bottom wall portion61, the cooling gas blown from the outlet41dof the fan41and introduced into the duct portion43cthrough the introduction port43d. Then, the cooling gas delivered from the delivery duct43is delivered to the flow paths60acontinuous with the flow path connection space60bthrough the flow path connection space60b. In this way, the cooling device40delivers the cooling gas to the flow paths60a.

In this case, the fan41is fixed to the base plate60on which the battery modules30are mounted, and thus the fan41can be positioned with respect to the battery modules30and fixed to the base plate60. Accordingly, the fan41can be positioned and fixed with respect to the battery modules30without using a bracket or the like for fixing the fan41, and the assemblability of the battery unit20is improved. Since the fan41is fixed to the base plate60, the fan41can be disposed in the vicinity of the flow paths60aformed between the lower surfaces of the battery modules30and the base plate60. Accordingly, a distance from the fan41to the flow paths60acan be shortened, so that the battery unit20can be miniaturized.

Since the opening43fof the delivery duct43is sealed by the bottom wall portion61of the base plate60and the upper surface of the support member64of the base plate60via the sealing member43g, the opening43fof the delivery duct43can be sealed only by mounting the delivery duct43from above so as to be in contact with the upper surface of the support member64of the base plate60and the bottom wall portion61of the base plate60, and the battery unit20can be easily assembled.

The introduction duct42is mounted on an upper surface of the fan41and the pedestal portion43hof the delivery duct43by inserting the pair of front and rear positioning pins42dprovided at the left end portion of the introduction duct42through the second engaging portions43nprovided on the pair of front and rear protrusions43iof the delivery duct43. Further, the introduction duct42is mounted on the upper surface of the fan41and the pedestal portion43hof the delivery duct43by fitting the discharge port42cto the aspiration port41cof the fan case41b.

In this case, since the aspiration port41cof the fan41opens upward and the introduction duct42is disposed above the fan41, the introduction duct42is easily assembled to the battery unit20such that the discharge port42cof the introduction duct42and the aspiration port41cof the fan case41bare fitted to each other.

When the introduction duct42is attached to the upper surface of the fan41and the pedestal portion43hof the delivery duct43, the pair of front and rear positioning pins42dprovided at the left end portion of the introduction duct42are inserted through the second engaging portions43nprovided on the pair of front and rear protrusions43iof the delivery duct43, so that the introduction duct42can be easily positioned with respect to the delivery duct43, and thus the assemblability of the battery unit20is improved.

Further, since the second engaging portions43nof the delivery duct43are provided on the upper surface431of the delivery duct43, the introduction duct42can be attached to the upper surface of the fan41and the pedestal portion43hof the delivery duct43from above, and when the introduction duct42is attached to the upper surface of the fan41and the pedestal portion43hof the delivery duct43from above, positions of the second engaging portions43nof the delivery duct43can be easily confirmed, and thus the assemblability of the battery unit20is further improved.

The battery unit20further includes a junction board bracket73which extends above the introduction duct42and supports the junction board52. Therefore, the introduction duct42is disposed between the fan41and the junction board bracket73. The junction board bracket73includes a main plate730which extends in the front-rear direction and the vehicle width direction at a position overlapping the introduction duct42when viewed from the upper-lower direction.

A left center fixing portion730ais provided at a position substantially in a center in a front-rear direction of a left end portion of the main plate730. A through hole which is penetrated in the upper-lower direction is formed in the left center fixing portion730a.

The junction board bracket73further includes a first extending portion731which bends downward from a right front end portion of the main plate730and extends downward from the main plate730. A lower end portion731aof the first extending portion731bends in a front right direction and extends in a substantially horizontal direction. A right front fixing portion731bis provided at the lower end portion731aof the first extending portion731. The right front fixing portion731bis formed with a through hole which is penetrated in the upper-lower direction and can be inserted through by the front male screw pin66aof the pair of front and rear male screw pins66aprovided on the first fan mounting portion66of the base plate60.

The junction board bracket73further includes a second extending portion732which protrudes to the right from a right rear end portion of the main plate730and extends substantially in the horizontal direction. A right rear fixing portion732bis provided at a right end portion732aof the second extending portion732. The right rear fixing portion732bis formed with a through hole which is penetrated in the upper-lower direction and can be inserted through by the male screw pin82bprovided on the protrusion82aformed on the right end portion of the rear frame82described above.

The main plate72aof the right battery module bracket72is provided with a flat plate-shaped extending portion72dwhich extends to the right direction from the main plate72aand extends in the front-rear direction and the vehicle width direction. The extending portion72dis provided with an insertion hole72ewhich is penetrated in the upper-lower direction, and a nut member72fis fixed to a lower surface of the extending portion72dat a position overlapping the insertion hole when viewed from the upper-lower direction.

A bolt73ais inserted from above into the through hole which is formed in the left center fixing portion730aand is penetrated in the upper-lower direction. The bolt73ais fastened to the nut member72fby being inserted through the insertion hole72eprovided in the extending portion72dof the right battery module bracket72. Accordingly, the left center fixing portion730ais fixed to the right battery module bracket72.

In the pair of front and rear male screw pins66aprovided on the first fan mounting portion66of the base plate60, the front male screw pin66apenetrates the insertion hole formed in the lug portion41eof the fan case41band protrudes above the lug portion41e. Then, in the pair of front and rear male screw pins66aprovided on the first fan mounting portion66of the base plate60, the front male screw pin66apenetrates from a lower side into the through hole formed in the right front fixing portion731band penetrated in the upper-lower direction. Then, a fastening member such as a nut is fastened from above to the front male screw pin66aof the pair of front and rear male screw pins66aprovided on the first fan mounting portion66of the base plate60, so that the right front fixing portion731bis fastened together with the lug portion41eof the fan case41b, and is fixed to the first fan mounting portion66of the base plate60together with the fan41.

The male screw pin82bprovided on the protrusion82aformed at the right end portion of the rear frame82penetrates, from a lower side, the through hole formed in the right rear fixing portion732band penetrated in the upper-lower direction. Then, a fastening member such as a nut is fastened from above to the male screw pin82bprovided on the protrusion82aformed at the right end portion of the rear frame82, so that the right rear fixing portion732bis fixed to the protrusion82aformed at the right end portion of the rear frame82.

Accordingly, the junction board bracket73includes the left center fixing portion730afixed to the right battery module bracket72, the right front fixing portion731bfixed to the base plate60, and the right rear fixing portion732bfixed to the rear frame82. Therefore, the junction board bracket73is fixed to the right battery module bracket72, the base plate60, and the rear frame82.

Therefore, the right battery module bracket72is fixed to the support member64of the base plate60at the lower end portion72c, and is fixed to the first fan mounting portion66of the base plate60and the protrusion82aof the rear frame82via the junction board bracket73at the extending portion72d. Therefore, the right battery module bracket72is fixed to the base plate60at a plurality of locations including at least the lower end portion72cand the extending portion72d. Accordingly, the right battery module bracket72is firmly fixed by the base plate60, and thus the battery modules30supported by the right battery module bracket72can be prevented from vibrating in the battery unit20.

The junction board bracket73is fixed to the right battery module bracket72, the base plate60, and the rear frame82such that the main plate730is in contact with the introduction duct42and the main plate730pushes the introduction duct42downwards. In this way, the junction board bracket73urges the introduction duct42toward the aspiration port41cof the fan41.

Accordingly, the introduction duct42can be attached to the fan41while maintaining high sealing performance between the discharge port42cof the introduction duct42and the aspiration port41cof the fan41without using an additional component such as a fastening member. Thus, the assemblability of the battery unit20is improved.

As illustrated inFIGS.4,8, and10, the junction board52is disposed above the junction board bracket73, is mounted on an upper surface of the junction board bracket73, and is supported by the junction board bracket73.

The junction board52is formed with insertion holes52bwhich are penetrated in the upper-lower direction at four locations of a left front end portion, a left rear end portion, a right front end portion, and a right rear end portion.

The main plate730of the junction board bracket73is formed with insertion holes73bwhich are penetrated in the upper-lower direction at positions overlapping the insertion holes52bformed in the junction board52when viewed from the upper-lower direction. A nut is fixed to a lower surface of the main plate730at a position overlapping each insertion hole73bwhen viewed from the upper-lower direction.

Bolts are inserted from above into the insertion holes52bat the left front end portion, the left rear end portion, the right front end portion, and the right rear end portion of the junction board52. The bolts to be inserted into the insertion holes52bof the junction board52from above penetrate the insertion holes52bof the junction board52and the insertion holes73b, formed at the positions overlapping the insertion holes52b, of the junction board bracket73, and is fastened to the nuts fixed at the position overlapping the insertion holes73b. Accordingly, the junction board52is disposed above the junction board bracket73and is supported by the upper surface of the junction board bracket73.

In this way, the junction board52is disposed above the cooling device40at the position where at least the part of the junction board52overlaps the cooling device40when viewed from the upper-lower direction. The introduction duct42of the cooling device40is disposed between the junction board52and the fan41in the upper-lower direction.

(Assembling Cooling Device and Junction Board to Battery Unit)

As illustrated inFIGS.4to10, when assembling the battery unit20, first, the locking claw43pof the delivery duct43is locked to the outlet41dof the fan case41bto connect the delivery duct43and the fan41, the pair of front and rear male screw pins66aprovided on the first fan mounting portion66are inserted into the insertion holes formed in the lug portions41eprovided at the right front region of the fan case41band the right rear region of the fan case41b, the male screw pin67aprovided at the second fan mounting portion67is inserted into the insertion hole formed in the lug portion41eprovided at the left rear region of the fan case41b, and the first engaging portions43jof the delivery duct engage with the male screw pins64dprovided on the upper surface of the support member64and with the fastening members64efastened to the male screw pins64d, so that the fan41and the delivery duct43are mounted on the base plate60. Then, a fastening member such as a nut is fastened from above to the rear male screw pin66aand the rear male screw pin67aprovided in the first fan mounting portion66.

Next, the discharge port42cof the introduction duct42is fitted to the aspiration port41cof the fan41, and the pair of front and rear positioning pins42dof the introduction duct42engage with the second engaging portions43nof the delivery duct43, so that the introduction duct42is mounted on the upper surface of the fan41and the pedestal portion43hof the delivery duct43.

Next, the front male screw pin66aprovided on the first fan mounting portion66of the base plate60penetrates the through hole formed in the right front fixing portion731b, and the male screw pin82bprovided on the protrusion82aof the rear frame82penetrates the through hole formed in the right rear fixing portion732b, so that the junction board bracket73is mounted on the upper surface of the introduction duct42. Then, fastening members such as nuts are fastened from above to the front male screw pin66aprovided on the first fan mounting portion66of the base plate60and the male screw pin82bprovided on the protrusion82aof the rear frame82, and the bolt73ais inserted from above into the through hole formed in the left center fixing portion730aand fastened to the nut member72fprovided on the extending portion72dof the right battery module bracket72.

Next, the junction board52is mounted on the upper surface of the junction board bracket73. Then, the bolts are inserted from above into the insertion holes52bof the junction board52and the insertion holes73b, formed at the positions overlapping the insertion holes52b, of the junction board bracket73, and are fastened to the nuts fixed at the positions overlapping the insertion hole73b.

Accordingly, the fan41, the delivery duct43, the introduction duct42, the junction board bracket73, and the junction board52can be assembled to the battery unit20. Therefore, the fan41, the delivery duct43, the introduction duct42, the junction board bracket73, and the junction board52can be mounted in this order and assembled to the battery unit20from above, and thus the assemblability of the battery unit20is further improved.

As illustrated inFIGS.4,9, and10, the junction board bracket73includes a stay73cwhich supports the service plug53. The stay73cis provided at the right front end portion of the main plate730, and at a position where the first extending portion731is adjacent to a right side of the stay73cand the introduction port42bof the introduction duct42is adjacent to a left side of the stay73c. The stay73cincludes a fixing portion73c1which extends so as to face an upper surface of the main plate730, and a service plug support portion73c2which is bent from a front end portion of the fixing portion73c1and is inclined rearward from the front end of the fixing portion73c1and extends upward. A front surface of the service plug support portion73c2faces diagonally upward and forward. The stay73cis fixed to the main plate730such that in the front-rear direction, the front end portion of the fixing portion73c1is located at substantially the same position as the front end portion of the main plate730or in front of the front end portion of the main plate730. In the stay73c, a lower surface of the fixing portion73c1is fixed to the upper surface of the main plate730. The stay73cis fixed to the main plate730by joining the lower surface of the fixing portion73c1and the upper surface of the main plate730by, for example, welding or the like.

The service plug53is supported on the front surface of the service plug support portion73c2facing diagonally upward and forward. In the present embodiment, the service plug53is provided adjacent to a right side of the introduction port42bof the introduction duct42. Therefore, both the junction board52and the service plug53are supported by the junction board bracket73, and thus, the wiring member which electrically connects the external device (not illustrated) and the junction board52can be prevented from bending between the junction board52and the service plug53due to vibration of the junction board bracket73. In addition, since the junction board52and the service plug53are both supported by the junction board bracket73, the service plug53can be easily assembled to the battery unit20.

As illustrated inFIGS.2,3, and7, the battery unit20further includes the battery control device bracket74which supports the battery control device51. The battery control device bracket74has a main plate74aextending in the upper-lower direction and the vehicle width direction.

The upper end portion72bof the right battery module bracket72is provided with a pair of front and rear male screw pins72gwhich penetrate the upper end portion72bin the upper-lower direction, protrude upward, and have a substantially columnar shape. An outer peripheral surface of each male screw pin72gis male-threaded.

A right end portion of the main plate74ais formed with a pair of front and rear insertion holes which are penetrated in the upper-lower direction and can be inserted through by the male screw pins72g. The pair of front and rear male screw pins72gprovided on the upper end portion72bof the right battery module bracket72are inserted into the pair of front and rear insertion holes formed in the right end portion of the main plate74a, and a fastening member such as a nut is fastened to each male screw pin72gfrom above, so that the battery control device bracket74is fixed to the upper end portion72bof the right battery module bracket72. Therefore, the main plate74aof the battery control device bracket74extends from the upper end portion72bof the right battery module bracket72toward the left in the front-rear direction and the vehicle width direction. Further, the main plate74aof the battery control device bracket74faces the upper surfaces of the two battery modules30, and extends in the front-rear direction and the vehicle width direction at a position overlapping the two battery modules30arranged in the front-rear direction when viewed from the upper-lower direction.

The battery control device51has a substantially rectangular parallelepiped shape which is shortest in the upper-lower direction, and is provided with lug portions51aextending toward an outside of the battery control device51. The lug portions51aare provided at a front end portion of a right side surface of the battery control device51and a rear end portion of a left side surface of the battery control device51so as to extend outward in the vehicle width direction. Each lug portion51ais formed with an insertion hole which opens in the upper-lower direction.

When viewed from the upper-lower direction, at positions overlapping with the insertion holes formed in the lug portions51aprovided at a right front end portion and a left rear end portion of the battery control device51, the main plate74aof the battery control device bracket74is provided with substantially columnar male screw pins74bwhich are inserted through the main plates74ain the upper-lower direction and protrude upward. Then, the male screw pins74bprovided on the main plate74aof the battery control device bracket74are respectively inserted into the insertion holes formed in the lug portions51aprovided at the right front end portion and the left rear end portion of the battery control device51, and fastening members such as nuts are fastened to the male screw pins74bfrom above, so that the battery control device51is fixed to the main plate74aof the battery control device bracket74.

As illustrated inFIGS.1to3and7, the battery unit20further includes a battery unit cover91which straddles the center tunnel11bof the floor panel10in the vehicle width direction and covers an upper side of the accommodation recessed portion121. The battery unit cover91covers the two battery modules30, the cooling device40, the battery control device51, the junction board52, the service plug53, the base plate60, the front frame81, and the rear frame82from above. The battery unit cover91is fixed to the floor panel10. The battery unit cover91is made of a metal material and functions as a part of a body skeleton of the vehicle V. Therefore, the battery unit cover91fixed to the floor panel10improves a rigidity of the body skeleton of the vehicle V.

The battery unit cover91includes an upper wall portion911which extends in the front-rear direction and the vehicle width direction and faces upward, and a side wall portion912which surrounds front, rear, left, and right outer edge portions of the upper wall portion911and extends downward from the front, rear, left, and right outer edge portions of the upper wall portion911. The side wall portion912includes: a front wall portion912awhich is bent from a front edge portion of the upper wall portion911, is inclined diagonally forward and downward, and extends in the vehicle width direction; a rear wall portion912bwhich bends from a rear edge portion of the upper wall portion911, is inclined diagonally rearward and downward, and extends in the vehicle width direction; a left wall portion912cwhich is bent from a left edge portion of the upper wall portion911, is inclined diagonally downward to the left, and extends in the vehicle width direction; and a right wall portion912dwhich bends from a right edge portion of the upper wall portion911, inclines diagonally downward to the right, and extends in the vehicle width direction.

The battery unit20is mounted on the vehicle V such that the battery modules30are arranged to make a stacking direction of the battery cells31as the vehicle width direction, and such that the cooling device40and the junction board52are disposed on a right side of the battery module30in the vehicle width direction. Therefore, the battery unit20is mounted on the vehicle V such that a longitudinal direction extends in the vehicle width direction. The vehicle V is provided with the rear seat RS so as to cover the upper wall portion911of the battery unit cover91. That is, the battery unit20is mounted under the rear seat RS of the vehicle V.

The battery unit20is formed with an accommodating space21surrounded by the battery unit cover91and the base plate60. The accommodating space21accommodates the two battery modules30, the cooling device40, the battery control device51, the junction board52, and the service plug53.

The front wall portion912aof the battery unit cover91is formed with a first opening91ahollowed out along a shape of the introduction port42bof the introduction duct42. Then, the cooling gas is introduced into the accommodating space21of the battery unit20through the first opening91aof the battery unit cover91. In this case, since the first opening91aof the battery unit cover91has the shape hollowed out along the shape of the introduction port42bof the introduction duct42, the cooling gas introduced into the accommodating space21of the battery unit20through the first opening91aof the battery unit cover91is introduced into the introduction port42bof the introduction duct42.

The front wall portion912aof the battery unit cover91is provided with a second opening91bon a right side of the first opening91a. The battery unit20is capable of inserting and removing the service plug53by inserting a finger or an instrument into the accommodating space21of the battery unit20through the second opening91bof the battery unit cover91.

An intake duct92which takes in air in the vehicle cabin CB as the cooling gas for the battery unit20is attached to the front wall portion912aof the battery unit cover91. The intake duct92includes an intake port92awhich opens toward the vehicle cabin CB, a discharge port92bwhich opens so as to surround the first opening91aof the battery unit cover91, and a duct portion92cwhich communicates the intake port92aand the discharge port92band is surrounded by a wall surface of the intake duct92. The intake port92aof the intake duct92is disposed substantially in the center of the vehicle width direction so as to straddle the center tunnel11bin the vehicle width direction. The duct portion92cof the intake duct92extends in the vehicle width direction from the intake port92aprovided substantially in the center in the vehicle width direction to the discharge port92bprovided at a position overlapping the first opening91aof the battery unit cover91. The intake duct92is attached such that an upper end portion of the intake port92ais substantially at the same position as the upper wall portion911of the battery unit cover91in the upper-lower direction.

An intake grill93having a mesh shape, a grid shape, a honeycomb shape, or the like is attached to the intake duct92so as to cover the intake port92a. A carpet14is laid on an upper surface of the front floor panel11which constitutes the floor portion of the vehicle cabin CB. The carpet14is hollowed out at a position overlapping the intake port92aof the intake duct92, and the intake grill93is attached to the intake duct92with the carpet14sandwiched between the intake grill93and the intake duct92.

The front wall portion912aof the battery unit cover91is formed with an exhaust port91cwhich discharges the cooling gas flowing through the accommodating space of the battery unit20to the outside of the battery unit. The exhaust port91cprotrudes forward from the front wall portion912aof the battery unit cover91to extend in the front-rear direction between the center tunnel11band the carpet14below the intake port92aof the intake duct92, and is formed so as to face an upper surface of the center tunnel11band substantially in the center of the vehicle width direction. Accordingly, the exhaust port91cis provided on a front side of the battery unit20. In the accommodating space of the battery unit20, the battery modules30are arranged so as to be offset from the substantially center in the vehicle width direction to the left direction, and the cooling device40and the junction board52are disposed on the right sides of the battery modules30, whereas the exhaust port91cis formed substantially in the center in the vehicle width direction. Therefore, the exhaust port91cis provided on a right side of the vehicle width direction center of the battery module30in the vehicle width direction, that is, closer to the junction board52than the vehicle width direction center of the battery module30in the vehicle width direction.

The exhaust port91ccommunicates with the accommodating space21of the battery unit20, and includes a wall portion91dwhich extends in the front-rear direction from the front wall portion912aof the battery unit cover91in a U-shape which opens downward when viewed from the front-rear direction. A left surface and a right surface of the wall portion91dare in contact with a left surface and a right surface of the center tunnel11b, respectively. The exhaust port91cis surrounded by the upper surface of the center tunnel11band the wall portion91d, and opens forward. Fixing portions91ewhich are recessed downward and in contact with the upper surface of the center tunnel are formed at a left front end portion and a right front end portion of the upper surface of the wall portion91d. The fixing portions91eare respectively provided with through holes which are penetrated in the upper-lower direction, and the exhaust port91cis fixed to the upper surface of the center tunnel11bby fastening bolts which penetrate the through holes from above to the upper surface of the center tunnel11b.

The battery unit20takes in the air in the vehicle cabin CB as the cooling gas of the battery unit20through the intake duct92and takes the cooling gas into the accommodating space21through the first opening91aof the battery unit cover91. The cooling gas taken into the accommodating space21from the first opening91aof the battery unit cover91flows through the flow path42afrom the introduction port42bof the introduction duct42, and is aspirated into the aspiration port41cof the fan41through the discharge port42c. The cooling gas aspirated into the aspiration port41cof the fan41is blown from the outlet41dof the fan41, and delivered from the delivery duct43through the flow path connection space60bto the flow paths60acontinuous with the flow path connection space60b. The cooling gas delivered to the flow paths60ais introduced into the battery modules30from the lower surfaces of the battery modules30, flows from the lower sides to the upper sides in the battery modules30to cool the battery modules30, and is discharged from the upper surfaces of the battery modules30.

In the accommodating space21of the battery unit20, an exhaust space22surrounded by the battery unit cover91is formed above the battery modules30. The upper surfaces of the battery modules30face the exhaust space22. Therefore, the cooling gas discharged from the upper surfaces of the battery modules30after cooling the battery modules30is discharged to the exhaust space22.

The exhaust space22extends in the vehicle width direction to an upper side of the junction board52. An upper part of the junction board52faces the exhaust space22. Therefore, since high-temperature air flows upward, the air whose temperature is raised by heat generated in the junction board52is discharged from the upper part of the junction board52to the exhaust space22.

The cooling gas discharged to the exhaust space22is discharged from the exhaust port91cprovided on the front wall portion912aof the battery unit cover91to an outside of the battery unit20, more specifically, to a space between the center tunnel11band the carpet14of the vehicle cabin CB. Therefore, the exhaust port91cprovided on the front wall portion912aof the battery unit cover91discharges the cooling gas discharged to the exhaust space22to the outside of the battery unit20.

In this way, the upper part of the junction board52faces the exhaust space22, so that the air whose temperature is raised by the heat generated in the junction board52is discharged to the exhaust space22, and is discharged to the outside of the battery unit20through the exhaust port91ctogether with the cooling gas which has cooled the battery modules30. Accordingly, the air whose temperature is raised by the heat generated in the junction board52can be prevented from staying inside the battery unit20, that is, in the accommodating space21of the battery unit20, and a cooling performance of the battery unit20is improved.

Then, the air whose temperature is raised by the heat generated in the junction board52is prevented from staying inside the battery unit20, that is, in the accommodating space21of the battery unit20, so that even if the battery unit20is mounted under the rear seat RS, the heat generated by the battery unit20can be prevented from being transferred to the rear seat RS. Accordingly, the battery unit20can be mounted under the rear seat RS without impairing a commercial value of the rear seat RS, and the battery unit20can be efficiently provided in a space of the vehicle V.

Further, the exhaust port91cis provided at the position closer to the junction board52than the vehicle width direction center of the battery module30in the vehicle width direction, and thus the air whose temperature is raised by the heat generated in the junction board52is more smoothly discharged to the outside of the battery unit20through the exhaust port91ctogether with the cooling gas which has cooled the battery modules30. Accordingly, the air whose temperature is raised by the heat generated in the junction board52can be further prevented from staying inside the battery unit20, that is, in the accommodating space21of the battery unit20, and the cooling performance of the battery unit20is further improved.

The junction board52is disposed above the cooling device40at the position where at least a part of the junction board52overlaps the cooling device40when viewed from the upper-lower direction, and the air whose temperature is raised by the heat generated in the junction board52flows upward, and thus the air whose temperature is raised by the heat generated in the junction board52can be prevented from being in contact with the cooling device40. Therefore, the heat generated in the junction board52can be prevented from being transferred to the cooling device40, and thus the cooling gas supplied from the cooling device40to the battery modules30can be prevented from rising in temperature due to the heat generated in the junction board52. Accordingly, a lower-temperature cooling gas can be supplied to the battery modules30, and the cooling performance of the battery unit20is improved.

The introduction duct42is disposed between the junction board52and the fan41in the upper-lower direction, and thus the junction board52is disposed above the introduction duct42, and the fan41is disposed below the introduction duct42. Therefore, even if the heat generated in the junction board52is transferred to the cooling device40, since the introduction duct42is disposed between the junction board52and the fan41in the upper-lower direction, the heat generated in the junction board52can be prevented from being transferred to the fan41. Further, since the fan41is disposed below the introduction duct42, the cooling gas which flows through a lower part of the introduction duct42is aspirated into the fan41. Therefore, even if the heat generated in the junction board52is transferred to the introduction duct42, in the cooling gas which flows through the introduction duct42, the cooling gas which flows through the lower part of the introduction duct42in which the heat generated in the junction board52is less likely to be transferred is aspirated into the fan41. Accordingly, a low-temperature cooling gas can be supplied to the battery modules30, and the cooling performance of the battery unit20is further improved.

The upper wall portion911of the battery unit cover91has a bulging portion911awhich bulges upward. The bulging portion911ais formed at a position overlapping the exhaust port91cand the center tunnel11bin the vehicle width direction and at a substantially central portion of the battery unit20in the vehicle width direction. An uppermost portion of the bulging portion911ais an uppermost portion911bof the upper wall portion911of the battery unit cover91. Therefore, the uppermost portion22aof the exhaust space22is formed at a position overlapping the exhaust port91cand the center tunnel11bin the vehicle width direction and at the substantially central portion of the battery unit20in the vehicle width direction.

The higher the temperature of the gas, the higher the gas flows, and thus the higher the temperatures of the cooling gas whose temperature is raised by cooling the battery modules30and the air whose temperature is raised by the heat generated in the junction board52, the more the cooling gas and the air flow toward the vicinity of the uppermost portion22aof the exhaust space22. Since the uppermost portion22aof the exhaust space22is formed at the position overlapping the exhaust port91cin the vehicle width direction, the cooling gas and the air flowing into the vicinity of the uppermost portion22aof the exhaust space22flow forward and are smoothly discharged to the outside of the battery unit20through the exhaust port91c. The higher-temperature cooling gas whose temperature is raised by cooling the battery modules30and the higher-temperature air whose temperature is raised by the heat generated in the junction board52can smoothly flow from the exhaust space22to the exhaust port91c, and thus the higher-temperature cooling gas whose temperature is raised by cooling the battery modules30and the higher-temperature air whose temperature is raised by the heat generated in the junction board52can be smoothly discharged to the outside of the battery unit20, and the cooling performance of the battery unit20is improved.

The upper wall portion911of the battery unit cover91includes, at the bulging portion911a, an inclined portion911cwhich is inclined upward toward the uppermost portion911b. The inclined portion911cextends in the vehicle width direction, and is formed such that a lower end portion911doverlaps the junction board52when viewed from the upper-lower direction. Therefore, the exhaust space22includes an inclined portion22bwhich is inclined upward toward the uppermost portion22a. The inclined portion22bextends in the vehicle width direction, and is formed such that the lower end portion22coverlaps the junction board52when viewed from the upper-lower direction.

Therefore, the higher-temperature air whose temperature is raised by the heat generated in the junction board52flows upward, and thus flows toward the uppermost portion911balong the inclined portion22b. Accordingly, the higher-temperature air whose temperature is raised by the heat generated in the junction board52can be guided to the vicinity of the uppermost portion911b, and thus the higher-temperature air whose temperature is raised by the heat generated in the junction board52can be more smoothly discharged to the outside of the battery unit20from the exhaust port91c.

Although one embodiment of the present invention has been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to such an embodiment. It is apparent to those skilled in the art that various variations and modifications can be conceived within the scope of the claims, and it is also understood that such variations and modifications belong to the technical scope of the present invention. In addition, the constituent elements in the above embodiment may be freely combined without departing from the spirit of the present invention.

At least the following matters are described in the present specification. In the parentheses, the corresponding constituent elements and the like in the above embodiment are shown as an example, and the present invention is not limited thereto.(1) A battery unit (battery unit20), including:at least one battery module (battery module30);a cooling device (cooling device40) configured to deliver a cooling gas configured to cool the battery module to the battery module, anda junction board (junction board52) mounted with a wiring component configured to electrically connect the battery module and an external device and allow a charging power and/or a discharging power of the battery module to flow, in which:the junction board is disposed above the cooling device at a position where at least a part of the junction board overlaps the cooling device when viewed from an upper-lower direction.

According to (1), the junction board is disposed above the cooling device at the position where at least the part of the junction board overlaps the cooling device when viewed from the upper-lower direction, and air whose temperature is raised by heat generated in the junction board flows upward, and thus the air whose temperature is raised by the heat generated in the junction board can be prevented from being in contact with the cooling device. Therefore, the heat generated in the junction board can be prevented from being transferred to the cooling device, and thus the cooling gas supplied from the cooling device to the battery module can be prevented from rising in temperature due to the heat generated in the junction board. Accordingly, a lower-temperature cooling gas can be supplied to the battery module, and a cooling performance of the battery unit is improved.(2) The battery unit according to (1), in which:the cooling device includes:a fan (fan41) configured to blow the cooling gas; andan introduction duct (introduction duct42) connected to an aspiration port (aspiration port41c) of the fan; andthe introduction duct is disposed between the junction board and the fan in the upper-lower direction.

According to (2), the introduction duct is disposed between the junction board and the fan in the upper-lower direction, and thus the junction board is disposed above the introduction duct and the fan is disposed below the introduction duct. Therefore, even if the heat generated in the junction board is transferred to the cooling device, since the introduction duct is disposed between the junction board and the fan in the upper-lower direction, the heat generated in the junction board can be prevented from being transferred to the fan. Further, since the fan is disposed below the introduction duct, the cooling gas which flows through a lower part of the introduction duct is aspirated into the fan. Therefore, even if the heat generated in the junction board is transferred to the introduction duct, in the cooling gas which flows through the introduction duct, the cooling gas which flows through the lower part of the introduction duct in which the heat generated in the junction board is less likely to be transferred is aspirated into the fan. Accordingly, the lower-temperature cooling gas can be supplied to the battery module, and the cooling performance of the battery unit is further improved.(3) The battery unit according to (1) or (2), further including:a battery unit cover (battery unit cover91) configured to cover the battery module, the cooling device, and the junction board from above, in which:the cooling device and the junction board are disposed on one side (right side) of the battery module in a first direction (vehicle width direction) orthogonal to the upper-lower direction;the cooling gas is introduced into the battery module from a lower surface of the battery module, flows from a lower side to an upper side in the battery module, and is discharged from an upper surface of the battery module;an exhaust space (exhaust space22) surrounded by the battery unit cover is formed above the battery module; andthe upper surface of the battery module and an upper part of the junction board face the exhaust space.

According to (3), since the upper part of the junction board faces the exhaust space, the air whose temperature is raised by the heat generated in the junction board is discharged to the exhaust space. Therefore, together with the cooling gas which has cooled the battery module, the air whose temperature is raised by the heat generated by the junction board can be discharged to an outside of the battery unit. Accordingly, the air whose temperature is raised by the heat generated in the junction board can be prevented from staying inside the battery unit, and the cooling performance of the battery unit is further improved.(4) The battery unit according to (3), further including:an exhaust port (exhaust port91c) configured to discharge the cooling gas discharged to the exhaust space to an outside of the battery unit, in which:the exhaust port is provided on one side (front side) of the battery module in a second direction (front-rear direction) orthogonal to both the upper-lower direction and the first direction; andan uppermost portion (uppermost portion22a) of the exhaust space is formed at a position overlapping the exhaust port in the first direction.

The higher the temperature of the gas, the higher the gas flows, and thus the higher the temperatures of the cooling gas whose temperature is raised by cooling the battery modules and the air whose temperature is raised by the heat generated in the junction board, the more the cooling gas and the air flow toward the vicinity of the uppermost portion of the exhaust space.

According to (4), since the uppermost portion of the exhaust space is formed at the position overlapping the exhaust port in the vehicle width direction, the cooling gas and the air flowing into the vicinity of the uppermost portion of the exhaust space flow in the second direction and are smoothly discharged to the outside of the battery unit through the exhaust port. Accordingly, a higher-temperature cooling gas whose temperature is raised by cooling the battery module and a higher-temperature air whose temperature is raised by the heat generated in the junction board can smoothly flow from the exhaust space to the exhaust port, and thus the higher-temperature cooling gas whose temperature is raised by cooling the battery module and the higher-temperature air whose temperature is raised by the heat generated in the junction board can be smoothly discharged to the outside of the battery unit, and the cooling performance of the battery unit is improved.(5) The battery unit according to (4), in which:the exhaust space includes an inclined portion (inclined portion22b) which is inclined upward toward the uppermost portion; andthe inclined portion is formed such that a lower end portion (lower end portion22c) overlaps the junction board when viewed from the upper-lower direction.

According to (5), the higher-temperature air whose temperature is raised by the heat generated in the junction board flows upward, and thus flows toward the uppermost portion along the inclined portion. Accordingly, the higher-temperature air whose temperature is raised by the heat generated in the junction board can be guided to the vicinity of the uppermost portion, and thus the higher-temperature air whose temperature is raised by the heat generated in the junction board can be more smoothly discharged to the outside of the battery unit through the exhaust port.(6) The battery unit according to (4) or (5), in which:the exhaust port is provided in the first direction at a position closer to the junction board than a center of the battery module in the first direction.

According to (6), in the first direction, the exhaust port is provided at the position closer to the junction board than the center of the battery module in the first direction, and thus the air whose temperature is raised by the heat generated in the junction board is more smoothly discharged to the outside of the battery unit through the exhaust port together with the cooling gas which has cooled the battery module. Accordingly, the air whose temperature is raised by the heat generated in the junction board can be further prevented from staying inside the battery unit, and the cooling performance of the battery unit is further improved.(7) The battery unit according to any one of (3) to (6), in which:the battery unit is mounted under a seat (rear seat RS) of a vehicle (vehicle V) such that the first direction extends in the vehicle width direction.

According to (7), the air whose temperature is raised by the heat generated in the junction board is prevented from staying inside the battery unit, so that even if the battery unit is mounted under the seat of the vehicle, heat generated in the battery unit can be prevented from being transferred to the seat of the vehicle. Accordingly, the battery unit can be mounted under the seat of the vehicle without impairing a commercial value of the seat, and the battery unit can be efficiently provided in a space of the vehicle.(8) The battery unit according to any one of (1) to (7), in which:the cooling device and the junction board are disposed on one side (right side) of the battery module in a first direction (vehicle width direction) orthogonal to the upper-lower direction, andthe cooling device and the junction board are disposed at a position where at least a part of each of the cooling device and the junction board overlaps the battery module when viewed from the first direction.

According to (8), the cooling device and the junction board are disposed such that at least a part of each of the cooling device and the junction board overlaps the battery module when viewed from the first direction, and thus the cooling device and the junction board can be disposed in the battery unit while preventing a height dimension of the battery unit.