JP7589072B2 - Vehicle battery frame - Google Patents

Description

The present invention relates to a vehicle battery frame that supports a battery on a vehicle body.

A module housing is known that includes a cold plate for removing heat generated from the battery cells (for example, Patent Document 1 (Figure 13B)). This cold plate cools the battery cells by circulating liquid inside it.

Special Publication No. 2020-514991

The module housing described in Patent Document 1 has the problem that the components that make up the cold plate itself limit the design freedom of the refrigerant flow path.

The problem that this invention aims to solve is to provide a vehicle battery frame that allows greater freedom in designing the refrigerant flow path.

The present invention solves the above problem by concentrating the bottom members in a second area of the bottom frame other than the first area in which the battery is mounted.

According to the present invention, it is possible to provide a vehicle battery frame that can increase the design freedom of the coolant flow path in the first region by concentrating the bottom members in a second region other than the first region in which the battery is mounted.

FIG. 1 is a perspective view showing a vehicle battery frame according to the present invention. FIG. 2 is a cross-sectional view taken along line II-II in FIG. FIG. 3(a) is a bottom view showing the bottom frame, and FIG. 3(b) is a bottom view showing the upper frame. FIG. 4 is an enlarged cross-sectional view showing the bottom member. FIG. 5 is a perspective view showing a state in which the vehicle battery frame of FIG. 1 is attached to the underside of the floor of an automobile body.

The following describes an embodiment of the present invention with reference to the drawings. Fig. 1 is a perspective view showing the vehicle battery frame of the present invention, Fig. 2 is a cross-sectional view taken along line II-II in Fig. 1, Fig. 3(a) is a bottom view showing the bottom frame, Fig. 3(b) is a bottom view showing the upper frame, Fig. 4 is an enlarged cross-sectional view showing the bottom member, and Fig. 5 is a perspective view showing the vehicle battery frame of Fig. 1 attached to the underside of the floor of an automobile body.

The vehicle battery frame 1 of this embodiment is attached to the underside of the floor of the vehicle body 2 and contacts and supports the battery 3. A refrigerant circulator 4 that circulates refrigerant through the vehicle battery frame 1 is connected to this vehicle battery frame 1. In other words, by attaching the vehicle battery frame 1 to the outside of the vehicle, it is possible to use the wind around the vehicle while it is moving to cool the vehicle battery frame 1 or the refrigerant, etc.

As shown in FIG. 1, the vehicle battery frame 1 includes a plate-shaped bottom frame 10, a plurality of plate-shaped side frames 11a, 11b, 11c, and 11d fixed to the outer periphery of the bottom frame 10, and a plate-shaped upper frame placed on the side frames 11a to 11d. The bottom frame 10 and the upper frame 15 in this embodiment are made of one member, but are not limited to this and may be made of two or more members joined together. The side frames 11a to 11d are made of four members, but are not limited to this and may be made of less than four or five or more side frames. The bottom frame 10, the side frames 11a to 11d, and the upper frame 15 can be made of aluminum extrusions, but are not limited to these, and if they are made of aluminum extrusions, they will have excellent heat transfer, weight reduction, and noise shielding properties.

2, the bottom frame 10 is a flat plate member having a first main surface 103 and a second main surface 104 on the opposite side. When assembled to the automobile body 2, the first main surface 103 corresponds to the upper surface, and the second main surface 104 corresponds to the lower surface. The bottom frame 10 is composed of a first region 101 and a second region 102 in a plan view, and the battery 3 is mounted in the first region 101. The battery 3 (also called a battery pack) includes a plurality of battery modules 31, each of which is housed in a rectangular parallelepiped module case. Although not shown, a plurality of thin batteries (also called single cells) are housed inside the module case in a stacked state. The battery 3 may be placed on the bottom frame 10 via a gap filler made of a urethane-based or silicone-based resin material.

Component parts of the vehicle battery frame 1, such as side frames 11a to 11d, are provided in a second region 102 other than the first region 101. The bottom members 12 are concentrated only in the second region 102. As shown in the bottom view of FIG. 3(a), in this embodiment, five bottom members 12 are provided at the center and left and right ends of the bottom frame 10, and the bottom members 12 extend along the front-rear direction of the automobile body 2. In this embodiment, five bottom members 12 are provided, but this is not limited thereto, and less than four or six or more bottom members 12 may be provided.

As shown in FIG. 4, the bottom member 12 is a hollow member having an upper plate 121, a lower plate 122 facing the upper plate 121 through a hollow portion 123, and a rib 124 connecting the upper plate 121 and the lower plate 122 in the hollow portion 123. By making the bottom member 12 have a hollow cross-sectional structure partially having the rib 124, it is possible to ensure a certain level of strength while reducing the weight.

As shown in FIG. 2, a cooling plate 13 is provided on the second main surface 104 of the first region 101. In this embodiment, the cooling plate 13 is provided only in the first region 101. This cooling plate 13 has a joint 131 at an end, and is joined to the bottom frame 10 via this joint 131. The joint 131 is not particularly limited, but may be joined to the bottom frame 10 by welding, or may be joined to the bottom frame 10 by a fastener such as a bolt.

The cooling plate 13 also has a curved portion 132 sandwiched between the joint portion 131 on both sides. The curved portion 132 is separated from the bottom frame 10 by curving in a direction away from the bottom frame 10. As a result, a space is formed between the bottom frame 10 and the cooling plate 13 in contact with the bottom frame 10, and this space is used as a flow path 133 for flowing the refrigerant. In this way, the flow path 133 is in contact with the bottom frame 10 on which the battery 3 is placed, so that the cooling efficiency of the battery 3 can be improved. In addition, since the number of parts between the flow path 133 and the battery 3 is small, the vehicle battery frame 1 can be made lighter and the energy density can be improved. Furthermore, the rigidity of the bottom frame can be increased by joining the cooling plate 13 having the curved portion 132 to the bottom frame 10 made of a flat plate member. In this embodiment, the cooling plate 13 is separate from the bottom frame 10, but this is not limited to this, and the cooling plate 13 may be formed integrally with the bottom frame 10.

In this embodiment, as shown in FIG. 3(a), two flow paths 133a, 133b are formed in the second main surface 104 of the bottom frame 10. Both of these flow paths 133a, 133b are interposed between the bottom members 12. That is, the first region 101 in which the battery 3 is mounted is disposed so as to be surrounded by the second region 102. By forming the bottom members 12 on both sides of the flow path 133, the strength of the bottom frame 10 can be improved, and thus the strength of the vehicle battery frame 1 can be improved.

In addition, in this embodiment, the flow paths 133 are formed over substantially the entire surface of the first region 101 in which the batteries 3 are mounted, so that all of the batteries 3 can be cooled evenly. The flow paths 133 have multiple main flow paths 134 extending in the left-right direction of the automobile body 2, and multiple connection flow paths 135 that connect the main flow paths 134 to each other.

The main flow path 134 has a planar shape that is substantially the same as the planar shape of the battery 3 (one side of a roughly rectangular parallelepiped), and in this embodiment, has a rectangular planar shape. This main flow path 134 faces the battery 3, and mainly cools the opposing battery 3. In this way, by making the shape of the part of the flow path 133 that faces the battery 3 substantially the same as the planar shape of the battery 3, the cooling efficiency of the battery 3 can be improved.

The connection flow path 135 connects one end of the main flow path 134 to the other end of the other main flow path 134. Therefore, the flow path 133 generally extends along the front-rear direction of the automobile body 2, and meanders by bending alternately along the left-right direction of the automobile body 2. By making the flow path 133 meander in this way, even when the flow path 133 is formed over the entire surface of the first region 101 as in this embodiment, it is not necessary to excessively widen the width of the flow path 133, so that the variation in the flow rate of the refrigerant flowing through the flow path 133 can be suppressed. Therefore, uneven cooling of the battery 3 can be reduced.

As shown in FIG. 1, the four side frames 11a to 11d are fixed to the outer periphery of the bottom frame 10 by welding or the like. As shown in FIG. 2, the side frames 11a to 11d are all basically the same, with a hollow cross-sectional structure that partially has ribs 111. By making the side frames 11a to 11d have a hollow cross-sectional structure that partially has ribs 111, it is possible to ensure a certain level of strength while reducing weight.

As shown in FIG. 1, a number of cross members 14 are provided between the side frames 11a, 11b and fixed to the bottom frame 10 by welding or the like. In this embodiment, the cross members 14 connect the opposing side frames 11a, 11b, thereby improving the strength of the vehicle battery frame 1. The battery 3 is stored in a space surrounded by the bottom frame 10, the underside floor 21 of the vehicle body 2 facing it, the four side frames 11a to 11d, and the cross members 14. In the vehicle battery frame 1, as shown in FIG. 1, the batteries 3 are mounted in the four front compartments separated by the cross members 14, and the batteries 3 with a smaller number of battery modules 31 arranged in each compartment are mounted in the two rear compartments separated by the cross members 14.

The battery 3 is also mounted on the upper frame 15. As shown in the bottom view of FIG. 3(b), a bottom member 151 and a cooling plate 152 are provided on the underside of this upper frame 15, similar to the bottom frame 10, and the cooling plate 152 forms flow paths 152a, 152b through which the refrigerant flows. In this upper frame 15, the bottom member 151 is arranged to surround the periphery (four sides) of the cooling plate 152.

As shown in FIG. 5, the vehicle battery frame 1 of this embodiment is attached to almost the entire surface of the underside 21 of the vehicle body 2, from the front of the front floor panel 23 to the rear floor panel 24. Note that the reference numerals 22 and 25 indicate dash panels and sills, respectively.

As shown in FIG. 1, the refrigerant circulator 4 of this embodiment includes a flow path 41 through which the refrigerant flows, a pump 42 that flows the refrigerant, a cooler 43 that cools the refrigerant, and a refrigerant tank 44. The refrigerant tank 44 is not an essential component for the refrigerant circulator 4. A detailed configuration of the refrigerant circulator 4 of this embodiment is shown in FIG. 3(a). As the refrigerant, a liquid refrigerant or a gas refrigerant can be used. As the liquid refrigerant, an antifreeze solution (long life coolant LLC) mainly composed of ethylene glycol or water can be used. As the gas refrigerant, carbon dioxide gas, specific fluorocarbons, alternative fluorocarbons, etc. can be used. As the alternative fluorocarbons, fluorine-based organic compounds such as hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs) can be used. The cooler 43 of this embodiment shown in FIG. 1 and FIG. 3(a) shows an example in which a liquid refrigerant such as antifreeze is used, and the liquid refrigerant consisting of antifreeze is cooled by exchanging heat with the refrigerant of the cooling cycle 5 of the automotive air conditioning device installed in the automobile.

That is, the cooling cycle 5 of the automotive air conditioner shown in FIG. 3(a) includes a compressor 53 that compresses high-temperature gas-phase refrigerant, a condenser 51 that uses a fan 52 to air-cool and condense the high-temperature, high-pressure gas-phase refrigerant compressed by the compressor 53, and an evaporator 54 that adiabatically expands the low-temperature liquid-phase refrigerant condensed by the condenser 51 and exchanges heat with the air introduced into the vehicle cabin.

In this embodiment, the low-temperature liquid refrigerant condensed by the condenser 51 of the cooling cycle 5 of the automotive air conditioner is branched off from the upstream side of the evaporator 54 and introduced as a cooling heat source for the cooler 43. That is, the low-temperature side refrigerant inlet and outlet of the cooler 43 are connected in parallel with the evaporator 54, and the high-temperature side inlet and outlet are connected to the flow path 41. This allows the heated liquid refrigerant that is returned to the cooler 43 after exchanging heat with the battery 3 in the bottom frame 10 to be cooled by exchanging heat with the refrigerant of the cooling cycle 5 in the cooler 43. In FIG. 3(a), the reference numeral 55 denotes a refrigerant pipe, the reference numeral 56 denotes a three-way valve, and the reference numerals 57 and 58 denote check valves.

The liquid refrigerant cooled by the cooler 43 is stored in the refrigerant tank 44 and then sucked by the pump 42, and guided from the flow path 41 downstream of the pump 42 to the flow path 133a provided in the bottom frame 10. The liquid refrigerant guided to the flow path 133a is guided from the flow path 133a to the flow path 152a, flow path 152b, and flow path 133b in this order, and then guided to the cooler 43. Note that the flow paths 133a, 133b, 152a, and 152b are spaces (through holes) defined by the bottom frame 10 and the cooling plate 13, but the other flow paths 41 are composed of piping. In addition, in this embodiment, a method of exchanging heat with the refrigerant of an automobile air conditioning device is used as a cooling method for the refrigerant circulating in the vehicle battery frame 1, but is not limited to this. For example, a dedicated cooling device (chiller) may be used as a cooling method for the refrigerant circulating in the vehicle battery frame 1.

As shown in FIG. 2, the vehicle battery frame 1 configured in this manner is attached to the underside 21 of the floor of the vehicle body 2 using a number of brackets 16 after the top surface is closed with a cover 17. Specifically, as shown in the figure, the left and right sides of the vehicle battery frame 1 are attached to the sill inner panel 251 or the sill outer panel 252 of the sill 25, and the front and rear end edges are directly or indirectly attached to the front floor panel or the rear floor panel.

As described above, according to the vehicle battery frame 1 of this embodiment, by concentrating the bottom members 12 in the second region 102, it is possible to increase the design freedom of the flow path 133 of the liquid refrigerant in the first region 101. In particular, it is possible to increase the area (cooling area) of the flow path 133. Furthermore, according to this embodiment, since the bottom members 12 are concentrated in the second region 102, the strength of the vehicle battery frame 1 can be maintained at a certain level or higher.

The above-described embodiments are described to facilitate understanding of the present invention, and are not described to limit the present invention. Therefore, each element disclosed in the above embodiments is intended to include all design modifications and equivalents that fall within the technical scope of the present invention.

For example, in this embodiment, the vehicle battery frame 1 is provided outside the vehicle (under the floor), but this is not limited thereto and may be provided inside the vehicle.

REFERENCE SIGNS LIST 1...vehicle battery frame 10...bottom frame 101...first region 102...second region 103...first main surface 104...second main surface 11a to 11d...side frame 111...rib 12...bottom member 121...upper plate 122...lower plate 123...hollow portion 124...rib 13...cooling plate 131...joint portion 132...curved portion 133, 133a, 133b...flow path 134...main flow path 135...connection flow path 14...cross member 15...upper frame 16...bracket 17...cover 2...automobile body 21...underside of floor 22...dash panel 23...front floor panel 24...rear floor panel 25...sill 3...battery 31...battery module 311...main surface 312...side surface 4...refrigerant circulator 41...flow path 42: Pump 43: Cooler 44: Refrigerant tank 5: Cooling cycle 51: Condenser 52: Fan 53: Compressor 54: Evaporator 55: Refrigerant piping 56: Three-way valve 57, 58: Check valve

Claims (9)

A vehicle battery frame that is attached to an automobile body and contacts and supports a battery,
a plate-shaped bottom frame having a first main surface on which the battery is placed;
a bottom member provided on a second main surface of the bottom frame opposite to the first main surface, the bottom member reinforcing the bottom frame;
a flow path provided on the second main surface through which a coolant flows;
the bottom frame includes a first region in which the battery is mounted and a second region other than the first region,
the flow channel is disposed on the second main surface of the first region;
The bottom members are concentrated on the second main surface of the second region. a cooling plate, at least a portion of which is spaced apart from the second main surface;
The vehicle battery frame according to claim 1 , wherein the flow path is a space surrounded by the bottom frame and the cooling plate and in contact with the bottom frame. The vehicle battery frame according to claim 1 or 2, wherein the flow path is formed substantially over the entire surface of the first region. A vehicle battery frame according to any one of claims 1 to 3, wherein the flow path is serpentine in the first region. A vehicle battery frame according to any one of claims 1 to 4, in which the planar shape of the portion of the flow path facing the battery is substantially the same as the planar shape of the battery. The vehicle battery frame according to any one of claims 1 to 5, wherein the bottom member is a hollow member having an upper plate, a lower plate facing the upper plate through a hollow portion, and a rib connecting the upper plate and the lower plate in the hollow portion. A plurality of bottom members are provided,
The plurality of bottom members extend along a front-rear direction of the automobile body,
The vehicle battery frame according to any one of claims 1 to 6, wherein the flow passage is interposed between the bottom members. A plurality of plate-shaped side frames provided on the first main surface and fixed to an outer periphery of the bottom frame;
A cross member connecting the side frames facing each other,
The battery is stored in a space surrounded by the bottom frame, the underside of the floor of the vehicle body facing the bottom frame, the multiple side frames, and the cross member. The vehicle battery frame according to any one of claims 1 to 7. A vehicle battery frame according to any one of claims 1 to 7, which is attached to the underside of the floor of the vehicle body.

Images