CN219419158U - Battery thermal management system - Google Patents

Abstract

The utility model provides a battery thermal management system, which relates to the technical field of batteries. The battery thermal management system includes a box body and a battery module. The battery module is accommodated in the box body. The side wall of the battery module is provided with a first heat dissipation cold plate. The first heat dissipation cold plate is arranged in the box body to dissipate heat from the side wall of the battery module. Compared with the prior art, the battery thermal management system provided by the utility model can dissipate heat from the side wall and the bottom wall of the battery module, and the heat dissipation effect is good. It can also prevent the heat production of the battery cell from exceeding the cooling capacity of the cooling system under the condition of continuous charging at a high rate, prevent the battery cell from exceeding the maximum temperature allowed by itself, and improve the service life of the battery cell.

Description

Battery thermal management system

technical field

The utility model relates to the technical field of batteries, in particular to a battery thermal management system.

Background technique

The research of the inventors found that with the rapid development of new energy vehicles, people's pursuit of vehicle power is getting higher and higher, and the fast charge rate of the battery system is increasing. The continuous rate of fast charge required by the vehicle reaches 4.5C. The heat generated by the battery cell has exceeded the heat dissipation capacity of the current cooling design.

At present, in the new energy market, the design of the battery system is mainly a single-sided cooling solution. The cooling surface is mainly on the bottom of the battery. Under the condition of continuous charging at a high rate, because the heat generated by the battery cell exceeds the cooling capacity of the cooling system, it is no longer possible to achieve a good heat dissipation effect.

Utility model content

The purpose of the utility model is to provide a battery thermal management system, which can realize good heat dissipation of the battery and improve the service life of the battery cell.

Embodiments of the utility model are achieved in that:

In a first aspect, the present invention provides a battery thermal management system, including a box body and a battery module. The battery module is accommodated in the box body. The side wall of the battery module is provided with a first heat dissipation cold plate. The first heat dissipation cold plate is arranged in the box body to dissipate heat from the side wall of the battery module.

In an optional embodiment, the battery module includes an end plate and at least two battery cells, a plurality of the battery cells are arranged side by side, the end plate is arranged at the ends of the plurality of the battery cells, and is connected to the box, and the first heat dissipation cold plate is arranged at both ends of the end plate, and is attached to the side wall of the corresponding battery cell.

In an optional embodiment, the battery thermal management system further includes a third heat dissipation cold plate, the third heat dissipation cold plate is arranged between two adjacent battery cells, and both sides of the third heat dissipation cold plate are respectively attached to the side walls of two adjacent battery cells.

In an optional embodiment, an escape groove is formed on the end plate, and the third heat dissipation cold plate is clamped and installed on the escape groove.

In an optional embodiment, a connection pipeline is further provided between the end of the third heat dissipation cold plate and the end of the second heat dissipation cold plate, and the connection pipeline connects the third heat dissipation cold plate and the second heat dissipation cold plate together in series, and the box body is also provided with a first inlet joint and a first outlet joint, and the connecting pipeline is connected to the first inlet joint and the first outlet joint at the same time.

In an optional embodiment, the box body includes a housing frame, a top cover and a bottom plate, the bottom plate is disposed on the bottom of the housing frame, the second heat dissipation cold plate is disposed on the bottom plate, the top cover is disposed on the top of the housing frame, the second heat dissipation cold plate is also provided with a heat conduction layer, and both sides of the heat conduction layer are attached to the second heat dissipation cold plate and the battery module respectively.

In an optional embodiment, a thermal insulation layer is attached to the inner side of the accommodating frame, and the thermal insulation layer is arranged opposite to the side wall of the battery module.

In an optional embodiment, an accommodating groove is provided on the inner side of the accommodating frame, and the heat insulation layer is embedded in the accommodating groove.

In an optional embodiment, the bottom of the housing frame is further provided with a fixed beam, and the two ends of the fixed beam are respectively connected to the opposite side walls of the housing frame, and the battery module is detachably mounted on the fixed beam.

In an optional embodiment, a fixed boss is provided on the bottom side of the fixed beam, and the fixed boss is pressed against the second heat dissipation cold plate, so that the second heat dissipation cold plate is spaced apart from the fixed beam.

The beneficial effects of the utility model embodiment include:

In the battery thermal management system provided by the embodiment of the present invention, a first heat dissipation cold plate is provided on the side wall of the battery module to dissipate heat from the side wall of the battery module, and a second heat dissipation cold plate is provided in the box to dissipate heat from the bottom wall of the battery module to realize common heat dissipation of the side wall and the bottom wall of the battery module, greatly increase the heat dissipation area, and further make the heat dissipation effect better, and can effectively control the temperature of the battery cell. Compared with the prior art, the battery thermal management system provided by the utility model can dissipate heat from the side wall and the bottom wall of the battery module, and the heat dissipation effect is good. It can also prevent the heat production of the battery cell from exceeding the cooling capacity of the cooling system under the condition of high-rate continuous charging, prevent the battery cell from exceeding the maximum temperature allowed by itself, and improve the service life of the battery cell.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings that need to be used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can also be obtained according to these drawings without creative work.

FIG. 1 is a schematic diagram of the internal structure of the battery thermal management system provided by the first embodiment of the present invention;

Fig. 2 is a schematic diagram of an exploded structure of the battery thermal management system provided by the first embodiment of the present invention;

Fig. 3 is a partial structural schematic diagram of the battery thermal management system provided by the first embodiment of the present invention;

Fig. 4 is a schematic structural view of the end plate in Fig. 3;

Fig. 5 is the partially enlarged schematic view of V in Fig. 1;

FIG. 6 is a schematic structural diagram of the accommodating frame in FIG. 1 .

icon:

100-battery thermal management system; 110-box body; 111-accommodating frame; 113-top cover; 115-bottom plate; 117-insulation layer; 119-accommodating groove; 130-battery module; 131-end plate; - heat conduction layer; 173 - fixed beam; 175 - fixed boss; 190 - third cooling cold plate.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of them. The components of the embodiments of the invention generally described and illustrated in the figures herein may be arranged and designed in a variety of different configurations.

Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of the present utility model.

It should be noted that like numerals and letters denote similar items in the following figures, therefore, once an item is defined in one figure, it does not require further definition and explanation in subsequent figures.

In the description of the utility model, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and so on is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship that is usually placed when the utility model product is used. construction and operation, therefore, should not be construed as limiting the utility model. In addition, the terms "first", "second", "third", etc. are only used for distinguishing descriptions, and should not be construed as indicating or implying relative importance.

Furthermore, the terms "horizontal", "vertical" and the like do not imply that a component is absolutely level or overhanging, but may be slightly inclined. For example, "horizontal" only means that its direction is more horizontal than "vertical", and it does not mean that the structure must be completely horizontal, but can be slightly inclined.

In the description of the present utility model, it should also be noted that, unless otherwise specified and limited, the terms "installation", "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be fixed connection, detachable connection, or integral connection; it can be mechanical connection or electrical connection; Those of ordinary skill in the art can understand the specific meanings of the above terms in the present utility model in specific situations.

As disclosed in the background technology, the heat dissipation of the battery module in the prior art usually adopts a single-sided heat exchange method, that is, a heat dissipation structure, such as a cold plate, is arranged on the bottom or side wall of the battery module, so as to dissipate heat on one side of the battery module. affect.

In addition, the battery system in the prior art has insufficient thermal insulation capacity in low-temperature weather, which seriously affects the battery life of the battery. At present, the battery system lacks heat preservation function. In the low-temperature environment, because the battery system is not designed for heat preservation, the battery cells are always in the low-temperature environment, and the performance attenuation at low temperature is serious. If other heating methods are used for heating, the energy of the system will be lost and the cruising range of the vehicle will be reduced.

In order to solve the above problems, the utility model provides a battery thermal management system, which can effectively solve the problems of battery overheating and heat preservation. The battery thermal management system provided by the present invention will be described in detail below.

first embodiment

Please refer to FIG. 1 to FIG. 4 , this embodiment provides a battery thermal management system 100 , which has a good heat dissipation effect, and can prevent the heat generated by the battery cell 133 from exceeding the cooling capacity of the cooling system under the condition of continuous charging at a high rate, prevent the battery cell 133 from exceeding the maximum temperature allowed by itself, and improve the service life of the battery cell 133 . At the same time, the heat preservation effect is good, and the temperature of the battery cell 133 can be maintained in a low temperature environment, and other heating methods are avoided for heating, thereby improving the cruising range of the vehicle.

This embodiment provides a battery thermal management system 100, which includes a box body 110 and a battery module 130. The battery module 130 is accommodated in the box body 110. The side wall of the battery module 130 is provided with a first heat dissipation cold plate 150. The first heat dissipation cold plate 150 is arranged in the box body 110 to dissipate heat from the side wall of the battery module 130. The box body 110 is also provided with a second heat dissipation cold plate 170, which is arranged on the battery module 1 The bottom side of the battery module 130 is used to dissipate heat from the bottom wall of the battery module 130 .

In the battery thermal management system 100 provided in this embodiment, a first heat dissipation cold plate 150 is provided on the side wall of the battery module 130 to dissipate heat from the side wall of the battery module 130 through the first heat dissipation cold plate 150, and a second heat dissipation cold plate 170 is also provided in the box body 110 to dissipate heat from the bottom wall of the battery module 130 through the second heat dissipation cold plate 170, realizing common heat dissipation of the side wall and the bottom wall of the battery module 130, greatly increasing the heat dissipation area, and further improving the heat dissipation effect Even better, the temperature of the battery core 133 can be effectively controlled.

It should be noted that there are at least two second heat dissipation cold plates 170 in this embodiment, which can dissipate heat on at least two side walls of the battery module 130 at the same time. Conventional heat dissipation is single-sided heat dissipation, and the heat dissipation area is usually the bottom surface of the battery module 130. If the area of the bottom surface is set as S1, the heat dissipation area of the battery module 130 in contact with the cold plate is also S1; in this embodiment, the heat dissipation area of the side of the battery module 130 is S2, and both sides of the battery module 130 are in heat dissipation contact with the cold plate, and the heat dissipation area of the two sides is 2×S2. The total heat dissipation area of the middle cell 133 is (S1+2×S2)>S1, that is, it is larger than the conventional heat dissipation design, and the heat dissipation area is increased.

In addition, it should be noted that this embodiment also adds a heat exchange path. The conventional heat dissipation path is heat exchange at the bottom, and the battery module 130 can only dissipate heat on the bottom surface. When the battery module 130 generates heat, the heat of the battery module 130 is transferred to the bottom surface of the battery module 130 through vertical heat conduction, and then transferred to the bottom cold plate; while the heat dissipation path designed in this embodiment allows the battery module 130 to dissipate heat on two sides and one bottom surface. The heat conducts heat through the horizontal and vertical directions, and the heat spreads through the shortest path, and the heat is taken away by the cold plate on the side and the cold plate on the bottom respectively. No matter in consideration of the heat exchange amount or the heat transfer path, the head of this embodiment can effectively control the heat of the battery module 130 .

The battery module 130 includes an end plate 131 and at least two battery cells 133. A plurality of battery cells 133 are arranged side by side. The end plate 131 is arranged at the end of the plurality of battery cells 133 and connected to the box body 110. The first heat dissipation cold plate 150 is arranged at both ends of the end plate 131 and attached to the side wall of the corresponding battery cell 133. Specifically, a plurality of battery cells 133 are neatly stacked in the box body 110, and its layout is consistent with that of conventional battery cells 133. End plates 131 are provided at both ends of each battery cell 133, and a plurality of spaced apart end plates 131 form a structure of avoidance grooves 135. During installation, the end plates 131 can be fixedly installed on the box body 110 first, and then a plurality of battery cells 133 can be loaded. Moreover, the first heat dissipation cold plate 150 is disposed at both ends of the end plate 131 and attached to the side wall of the battery cell 133 , the first heat dissipation cold plate 150 also plays a role of fixing the battery cell 133 while dissipating heat.

In this embodiment, the first heat dissipation cold plate 150 can be bonded to the side wall of the battery cell 133 with thermally conductive glue, and can also be bonded to the end of the end plate 131 with structural glue. Specifically, recessed bonding surfaces 139 are provided at both ends of the end plate 131 , and the edge of the first heat dissipation cold plate 150 can be bonded to the end plate 131 by coating the bonding surface 139 with structural glue. Wherein, the end plate 131 and the first heat dissipation cold plate 150 can jointly form a frame structure to cover a plurality of battery cells 133 , so as to function as a fixing structure and effectively fix the battery cells 133 .

Further, the battery thermal management system 100 also includes a third heat dissipation cold plate 190 , the third heat dissipation cold plate 190 is arranged between two adjacent battery cells 133 , and both sides of the third heat dissipation cold plate 190 are respectively attached to the side walls of two adjacent battery cells 133 . Specifically, there are multiple battery cells 133, and a third cooling plate 190 is arranged between two adjacent battery cells 133 arranged side by side. The two ends of the third cooling plate 190 are respectively installed on the two opposite end plates 131 to achieve fixation. By setting the third cooling plate 190, the battery core 133 in the middle position can also be dissipated. This further increases the heat dissipation area, thereby improving the heat dissipation capability.

In this embodiment, an escape groove 135 is defined on the end plate 131 , and the third heat dissipation cold plate 190 is clamped and installed on the escape groove 135 . Specifically, the center of the end plate 131 is provided with an avoidance groove 135 , and both ends of the third heat dissipation cold plate 190 are provided with clamping protrusions, and the clamping protrusions are assembled in the avoidance groove 135 , thereby realizing the fixing of the third heat dissipation cold plate 190 . Preferably, the third heat dissipation cold plate 190 can also be fixed and assembled in the avoidance groove 135 by structural glue, so as to further optimize the fixing effect.

In this embodiment, a connecting pipeline 137 is provided between the end of the third cooling plate 190 and the end of the first cooling plate 150. The connecting pipeline 137 connects the third cooling plate 190 and the first cooling plate 150 in series, and the box body 110 is also provided with a first inlet joint and a first outlet joint. The connecting pipeline 137 is connected to the first inlet joint and the first outlet joint at the same time. Specifically, one end of each of the first heat dissipation cold plate 150 and the third heat dissipation cold plate 190 is provided with a water inlet, which is connected to the water inlet through the connecting pipeline 137, so that a plurality of first heat dissipation cold plates 150 and a plurality of third heat dissipation cold plates 190 can be connected in series to form an integral circulation pipeline.

In this embodiment, a second inlet joint and a second outlet joint are provided on the box body 110 , and the second inlet joint and the second outlet joint are connected with the second heat dissipation cold plate 170 , so as to realize the liquid inflow and outflow from the second heat dissipation cold plate 170 .

It should be noted that in this embodiment, the first heat dissipation cold plate 150, the second heat dissipation cold plate 170, and the third heat dissipation cold plate 190 are all liquid-cooled heat dissipation cold plate structures, and their materials can be aluminum, copper, or a composite of plastic and metal. For specific structures and heat dissipation principles, reference can be made to existing cold plate structures.

Please continue to refer to Fig. 2 to Fig. 6, in this embodiment, box body 110 comprises accommodating frame 111, top cover 113 and base plate 115, and base plate 115 is arranged on the bottom of accommodating frame 111, and the second heat dissipation cold plate 170 is arranged on the base plate 115, and top cover 113 is arranged on the top of accommodating frame 111, is also provided with heat conduction layer 171 on the second heat dissipation cold plate 170, and the two sides of heat conduction layer 171 are connected with second heat dissipation cold plate 170 respectively. Fitted with the battery module 130. Specifically, the accommodating frame 111 is in the shape of a rectangular frame, and the top cover 113 and the bottom plate 115 are respectively arranged at the upper and lower ends of the accommodating frame 111 to form a closed chamber structure, and the battery module 130 is installed inside the chamber structure. Moreover, by setting the heat conduction layer 171 , the heat generated at the bottom of the battery cell 133 can be quickly conducted to the second heat dissipation cold plate 170 to realize heat transfer. The heat conduction layer 171 can be made of silica gel pad, polyurethane, epoxy resin and other materials, and its thermal conductivity is 0.01w*m/k˜20w*m/k.

It should be noted that in this embodiment, the second heat dissipation cold plate 170 is integrally arranged on the bottom plate 115, but in other preferred embodiments of the present invention, the second heat dissipation cold plate 170 can also be integrally arranged with the bottom plate 115, that is, the second heat dissipation cold plate 170 serves as the bottom structure of the box body 110 and acts as a structural member.

In this embodiment, an insulating layer 117 is attached to the inner side of the accommodating frame 111 , and the insulating layer 117 is disposed opposite to the sidewall of the battery module 130 . Specifically, the thermal insulation layer 117 is made of thermal insulation material, such as thermal insulation cotton. By attaching the thermal insulation layer 117 inside the housing frame 111, it can play a role of thermal insulation and prevent the heat of the internal battery 133 module from dissipating in large quantities through the housing frame 111. Wherein, the thermal insulation material can be polyurethane foam, EPDM, silicone foam and other materials, and its thermal conductivity is 0.001w*m/k˜5w*m/k.

In this embodiment, an accommodating groove 119 is defined inside the accommodating frame 111 , and the heat insulating layer 117 is embedded in the accommodating groove 119 . Specifically, by opening the accommodating groove 119 , it is possible to facilitate the installation of the thermal insulation layer 117 and fix the thermal insulation layer 117 to prevent the thermal insulation layer 117 from falling.

It should be noted that since the first heat dissipation cold plate 150 on the side is integrated with the battery module 130, the first heat dissipation cold plate 150 is directly exposed inside the battery pack module. When the internal ambient temperature of the battery module 130 rises and is higher than the temperature of the first heat dissipation cold plate 150 itself, the internal air temperature will heat the first heat dissipation cold plate 150. In addition, if the temperature difference between the first heat dissipation cold plate 150 and the environment is too large, condensation will also occur. In order to solve the above problems, the outside of the first heat dissipation cold plate 150 on the side of the module is designed There is insulation cotton to reduce the impact of the air in the bag on the cold plate and absorb condensation at the same time. At the same time, when the external temperature is too high (such as summer exposure), the external environment will heat the battery box 110, and the temperature of the box 110 will rise accordingly, and the temperature in the battery pack will be heated by the box 110. Setting the insulation layer 117 can further reduce the influence of the external environment temperature.

In this embodiment, the bottom of the housing frame 111 is further provided with a fixed beam 173, which is arranged close to the bottom plate 115, and the two ends of the fixed beam 173 are respectively connected to the opposite side walls of the housing frame 111, and the battery module 130 is detachably installed on the fixed beam 173. Specifically, the fixed beam 173 is horizontally placed in the accommodating frame 111 for carrying the battery module 130 , wherein the end plate 131 can be fixed on the fixed beam 173 by screws or other connectors.

In this embodiment, the bottom side of the fixed beam 173 is provided with a fixed boss 175 , and the fixed boss 175 abuts against the second heat dissipation cold plate 170 so that the second heat dissipation cold plate 170 is spaced from the fixed beam 173 . Specifically, there may be a plurality of fixed beams 173, and the multiple fixed beams 173 span the bottom of the housing frame 111. By setting the fixed beams 173, the second heat dissipation cold plate 170 at the bottom and the housing frame 111 can be designed without contact. The fixing boss 175 is disposed on the bottom surface of the fixing beam 173 and protrudes downward. The fixing boss 175 can be embedded on the fixing beam 173 by riveting or nesting. And the second heat dissipation cold plate 170 is also provided with a matching position, so that the fixed boss 175 can directly contact the surface of the second heat dissipation cold plate 170, and there is no direct contact between the second heat dissipation cold plate 170 and the fixed beam 173, so that the heat transferred by the second heat dissipation cold plate 170 will not be directly transferred to the fixed beam 173, but is transferred through the fixed boss 175.

It should be noted that, the material of the fixing boss 175 can be polyurethane, metal aluminum, metal steel, nylon, epoxy board and the like.

In the battery thermal management system 100 provided in this embodiment, the side and bottom surfaces of the battery cell 133 are in contact with the cold plate. When the battery cell 133 is charged and discharged at a high rate under high temperature conditions, the temperature of the battery cell 133 can be effectively controlled due to the multi-surface cooling of the battery cell 133 . Both sides of a single battery cell 133 are designed with side cold plates. The side of a single battery cell 133 can be the first heat dissipation cold plate 150 or the third heat dissipation cold plate 190. The side cold plate is fixed on the side wall mating surface of the end plate 131. The two can be bonded by structural adhesive. The side cold plate can serve as the side plate of the battery cell 133 module to improve the strength of the overall battery cell 133 module. The third heat radiation cold plate 190 is fixed by the clamping force between the two rows of battery cells 133. The end plate 131 is designed with an escape groove 135 for cooperation with the third heat dissipation cold plate 190. In order to improve the strength of the module and make up for the tolerance between each component, thermal conductive structural glue can be coated between the battery core 133 and all cold plates. The side insulation cotton is also designed on the side of the battery module 130 , so as to improve the insulation capacity of the battery module 130 .

In this embodiment, the battery box 110 integrates side cold plates and bottom cold plates at the same time. The bottom plate 115 is designed at the bottom of the second heat dissipation cold plate 170 to protect the second heat dissipation cold plate 170. The connecting pipeline 137 can connect the inlet and outlet of the first heat dissipation cold plate 150, the inlet and outlet of the third heat dissipation cold plate 190, the first outlet joint and the second outlet joint in one body, thereby forming a liquid cooling system. In order to improve the thermal insulation performance of the entire battery system, a non-contact design is implemented between the second heat dissipation cold plate 170 and the box body 110, the second heat dissipation cold plate 170 is in direct contact with the fixed boss 175 on the cold plate, the heat of the second heat dissipation cold plate 170 will not be directly transferred to the fixed beam 173, but is transferred to the fixed beam 173 through the fixed boss 175. Further, in this embodiment, in order to improve the thermal insulation performance, accommodating grooves 119 are designed on the inner surface around the accommodating frame 111 for pasting the thermal insulation layer 117 .

To sum up, this embodiment provides a battery thermal management system 100. A first heat dissipation cold plate 150 is provided on the side wall of the battery module 130 to dissipate heat from the side wall of the battery module 130. A second heat dissipation cold plate 170 is also provided in the box body 110 to dissipate heat from the bottom wall of the battery module 130. At the same time, a third heat dissipation cold plate 190 is provided in the middle of the battery module 130 to realize battery The common heat dissipation of the side wall and the bottom wall of the module 130 greatly increases the heat dissipation area, thereby making the heat dissipation effect better, and can effectively control the temperature of the battery cell 133 . Moreover, in this embodiment, the inner wall of the accommodating frame 111 is also attached with a thermal insulation layer 117 , which can achieve good thermal insulation performance. The battery thermal management system 100 provided in this embodiment can dissipate heat from the side wall and the bottom wall of the battery module 130, and has a good heat dissipation effect. It can also prevent the heat generated by the battery cell 133 from exceeding the cooling capacity of the cooling system under the condition of high-rate continuous charging, prevent the battery cell 133 from exceeding the maximum temperature allowed by itself, and improve the service life of the battery cell 133. At the same time, the heat preservation effect is good, and the temperature of the battery cell 133 can be maintained in a low temperature environment, and other heating methods are avoided for heating, thereby improving the cruising range of the vehicle.

The above descriptions are only preferred embodiments of the utility model, and are not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present utility model shall be included in the protection scope of the present utility model.

Claims (10)

1. A battery thermal management system, characterized in that it comprises a box (110) and a battery module (130), the battery module (130) is accommodated in the box (110), the side wall of the battery module (130) is provided with a first heat dissipation cold plate (150), the first heat dissipation cold plate (150) is arranged in the box (110), and is used to dissipate heat on the side wall of the battery module (130), the box (11 0) A second heat dissipation cold plate (170) is also provided, and the second heat dissipation cold plate (170) is arranged on the bottom side of the battery module (130) for dissipating heat from the bottom wall of the battery module (130). 2. The battery thermal management system according to claim 1, characterized in that the battery module (130) comprises an end plate (131) and at least two battery cells (133), a plurality of the battery cells (133) are arranged side by side, the end plate (131) is arranged at the ends of the plurality of battery cells (133), and is connected to the box (110), and the first heat dissipation cold plate (150) is arranged at both ends of the end plate (131) and attached to the corresponding The side wall of the cell (133). 3. The battery thermal management system according to claim 2, characterized in that the battery thermal management system further comprises a third heat dissipation cold plate (190), the third heat dissipation cold plate (190) is arranged between two adjacent battery cells (133), and both sides of the third heat dissipation cold plate (190) are respectively attached to the side walls of two adjacent battery cells (133). 4. The battery thermal management system according to claim 3, characterized in that an escape groove (135) is formed on the end plate (131), and the third heat dissipation cold plate (190) is clamped and installed on the escape groove (135). 5. The battery thermal management system according to claim 3, characterized in that, a connection pipeline (137) is further provided between the end of the third heat dissipation cold plate (190) and the end of the first heat dissipation cold plate (150), and the connection pipeline (137) connects the third heat dissipation cold plate (190) and the first heat dissipation cold plate (150) together in series, and the box body (110) is also provided with a first inlet joint and a first outlet joint, and the connection pipeline (137) ) is simultaneously connected to the first inlet joint and the first outlet joint. 6. The battery thermal management system according to claim 1, characterized in that, the box (110) comprises an accommodating frame (111), a top cover (113) and a bottom plate (115), the bottom plate (115) is arranged at the bottom of the accommodating frame (111), the second heat dissipation cold plate (170) is arranged on the bottom plate (115), the top cover (113) is arranged on the top of the accommodating frame (111), the second heat dissipation cold plate A heat conduction layer (171) is also provided on the plate (170), and both sides of the heat conduction layer (171) are attached to the second heat dissipation cold plate (170) and the battery module (130) respectively. 7. The battery thermal management system according to claim 6, characterized in that, an insulation layer (117) is attached to the inner side of the housing frame (111), and the insulation layer (117) is arranged opposite to the side wall of the battery module (130). 8. The battery thermal management system according to claim 7, characterized in that, an accommodating groove (119) is provided on the inner side of the accommodating frame (111), and the thermal insulation layer (117) is embedded in the accommodating groove (119). 9. The battery thermal management system according to claim 6, characterized in that, the bottom of the housing frame (111) is further provided with a fixed beam (173), the two ends of the fixed beam (173) are respectively connected to the opposite side walls of the housing frame (111), and the battery module (130) is detachably mounted on the fixed beam (173). 10. The battery thermal management system according to claim 9, characterized in that, the bottom side of the fixed beam (173) is provided with a fixed boss (175), and the fixed boss (175) is pressed against the second heat dissipation cold plate (170), so that the second heat dissipation cold plate (170) is spaced apart from the fixed beam (173).