Cooling structure for a battery pack and battery pack

Abstract

Cooling structure for a battery pack, characterized in that the cooling structure for the battery pack comprises: a cooling plate assembly provided inside the battery pack, wherein the cooling plate assembly comprises a first cooling plate and several second cooling plates connected to the first cooling plate; wherein the first cooling plate is connected to the lower housing of the battery pack and a flow channel is formed inside the first cooling plate, which is connected to the second cooling plate; wherein the first cooling plate rests against the cell modules inside the battery pack and the second cooling plate is each connected to the busbars of each of the cell modules; and a liquid inlet opening and a liquid outlet opening, each connected to the flow channel;wherein the coolant is able to flow successively through each of the second cooling plates via the inlet opening and the flow channel and be discharged through the liquid outlet opening.

Description

Cross-references to related applicationsThe present application claims priority to Chinese Patent Application No. 20232067974.8 filed on Mar. 30, 2023 with the Chinese Patent Office and entitled "Cooling Structure for Battery Pack and Battery Pack", the entire contents of which are incorporated herein by reference.Technical FieldThe present application relates to the field of liquid cooling structures for batteries, and more particularly to a cooling structure for a battery pack and a battery pack.Background ArtIn order to meet the current demand for quick charging and high-power discharging of electric vehicles, battery packs in electric vehicles generally need to be equipped with a liquid cooling system for thermal management in order to avoid situations in which the battery packs overheat by quick charging and high-power discharging and therefore cannot be normally used. At present, liquid cooling systems are mostly made up of components such as liquid cooling plates and piping placed at the bottom of the battery module.With the increasing demand for short charging times and discharge powers of battery packs, there are increasingly more cases where battery packs are charged and discharged with higher power over a longer period of time. In the above situation, the bus bar that electrically connects the battery cells generates significant heat under the limited flow area (i.e., the bus bar area) due to limitations of the interior of the battery pack and its own size. The liquid cooling plate located on the lower side of the battery module is influenced by its position and cannot effectively conduct the heat away from the bus bar, thereby limiting the performance of the battery.Contents of the ApplicationIn view of the above, the object of the present application is to provide a cooling structure for a battery pack and a battery pack to solve the problem that the liquid cooling system of the existing battery pack cannot effectively dissipate the heat from the bus bar, thereby further restraining the performance of the battery.In order to achieve the above objects, the embodiments of this application apply the following technical solutions:A first aspect of the present application provides a cooling structure for a battery pack, the cooling structure for a battery pack comprising:a cooling plate assembly provided inside the battery pack, the cooling plate assembly comprising a first cooling plate and a plurality of second cooling plates connected to the first cooling plate; the first cooling plate being connected to the lower case of the battery pack, and a flow channel connected to the second cooling plate being formed inside the first cooling plate; the first cooling plate abutting against the cell modules inside the battery pack, and the second cooling plate being respectively connected to the bus bar of each cell module; and a liquid inlet port and a liquid outlet port respectively connected to the flow channel; wherein the coolant is capable of flowing through each of the second cooling plates through the liquid inlet port and the flow channel one by one and being discharged through the liquid outlet port.Further, the second cooling plate includes a main plate formed into a parallelepiped plate-like structure and two side plates, two of the side plates being connected to two ends of the main plate in the longitudinal direction, respectively.Further, the side plates are formed with a first cavity and an opening capable of communicating the first cavity with an exterior, the opening being fitted to the main plate so that both ends of the main plate in the longitudinal direction are connected to the side plates through the opening.Further, a plurality of second cavities are formed inside the main plate, which are arranged one behind the other in the height direction of the main plate, and each of the second cavities passes through both ends of the main plate along the longitudinal direction of the main plate, so that each of the second cavities is connected to the first cavity.Further, a plurality of third cavities are provided inside the first cooling plate to form the plurality of flow passages; and the first cooling plate is provided with a first communication hole at the upper surface of the first cooling plate capable of respectively connecting the flow passages to the liquid inlet port, the liquid outlet port, and the second cooling plate.Further, the second cooling plate is vertically connected to the first cooling plate, and the bottoms of the two side plates are each formed with a second communication hole corresponding to the first communication hole.Further, a support member is provided between the second cooling plate and the side shells of the battery pack such that the second cooling plate abuts the bus bar.Further, a heat conducting member is provided between the second cooling plate and the bus bar.Further, an insulating layer is sprayed and formed on the outer surface of the second cooling plate, the insulating layer having a thickness of less than 0.5 mm.A second aspect of the present application provides a battery pack, wherein the battery pack is provided with the above-mentioned cooling structure for the battery pack.As compared with the existing technology, the positive effects of the present application are as follows:According to the cooling structure for a battery pack and the battery pack of the present application, a cooling plate assembly including a first cooling plate and a plurality of second cooling plates connected to the first cooling plate is provided in the battery pack. The first cooling plate is connected to the lower case of the battery pack and abuts the cell modules; the second cooling plate is connected to the bus bar of each battery cell, respectively. Moreover, the cooling structure is also provided with a liquid inlet port, a liquid outlet port, and a flow channel that is located inside the first cooling plate and is connected to the second cooling plate, so that the coolant can flow through the liquid inlet port into the flow channel of the first cooling plate, then through the flow channel into the second cooling plate, and be discharged through the liquid outlet. In this way, the first cooling plate and the second cooling plate may each realize heat dissipation of the battery cell and the bus bar, so that the battery can more effectively develop its performance.Brief Description of the DrawingsIn order to more clearly illustrate the technical solutions in the specific embodiments or the prior art of the present application, the following briefly presents the accompanying drawings, which must be used in the description of the specific embodiments or the prior art. It is obvious that the accompanying drawings in the following description represent some of the embodiments of the present application, and that other drawings can be obtained based on the accompanying drawings for general technical personnel in this field, provided that they do not perform any user's work. FIG. 1 is a schematic view of a cooling structure according to the embodiments of the present application when located inside a battery pack; FIG. 2 is a plan view of the cooling structure according to the embodiments of the present application when located inside the battery pack; FIG. 3 is an enlarged schematic view at A according to the embodiments of the present application; FIG. 4 is a cross-sectional view of the cooling structure according to the embodiments of the present application when located inside the battery pack; FIG. 5 is an enlarged exploded view at B according to the embodiments of the present application; FIG. 6 is a schematic view of a cooling structure according to the embodiments of the present application; FIG. 7 is a partial schematic view of a coolant flow path according to the embodiments of the present application.Reference numerals in the figures: 10 case; 11 cell module; 12 battery cell; 13 bus bar; 21 first cooling plate; 210 third cavity; 211 first communication hole; 22 second cooling plate; 220 main plate; 2200 second cavity; 221 side plate; 2211 first cavity; 23 support member; 24 heat conducting member; 31 liquid inlet port; 32 liquid outlet port.Specific EmbodimentsHereinafter, the technical solution of the present application will be clearly and fully described in conjunction with the accompanying drawings. It goes without saying that the description of the exemplary embodiments represents only a part of the exemplary embodiments of the present application and not all exemplary embodiments.The assemblies of the embodiments of the present application generally described and illustrated in the figures herein may be arranged and configured in a variety of different configurations. Accordingly, the following detailed description of the embodiments of the present application shown in the figures is not intended to limit the scope of the claimed application, but rather to represent selected embodiments of the application.Based on the embodiments in the present application, all other embodiments which general technical personnel obtain without any creative efforts are included in the scope of this application.In describing the embodiment of the present application, it is necessary to note that an azimuth or positional relationship related to the terms such as "central", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like has the azimuth or positional relationship based on the drawing. They are intended to facilitate and simplify the description of the present application, rather than indicating or implying that the stated device or component must have a particular orientation, must be constructed and operated in a particular orientation. Moreover, the terms "first", "second", and "third" are used only for differentiated description, and cannot be understood to indicate relative meaning.In the present application, the terms "installation", "connection" and "connection" are to be understood in the broader sense, unless expressly stated otherwise or restricted. For example, it may be a fixed connection, a detachable connection or a one-piece connection; it may be a mechanical connection or an electrical connection; it may be a direct connection, an indirect connection via an intermediate medium or a connection within the two elements. For general technical personnel in this field, the specific meaning of the above terms in the present application can be understood depending on the specific circumstances.As shown in FIGS. 1 to 7, according to a first aspect of the present application, there is provided a cooling structure for a battery pack, including a cooling plate assembly disposed in the battery pack, and a liquid inlet port 31 and a liquid outlet port 32 for introducing and discharging the coolant. The cooling plate assembly includes a first cooling plate 21 and a plurality of second cooling plates 22, so that after the coolant entering the battery pack through the liquid inlet port 31 flows through the first cooling plate 21 and the second cooling plate 22, respectively, heat dissipation and cooling of the battery cell 12 and the bus bar 13, respectively, can be performed. Hereinafter, the specific configurations of the above-mentioned individual parts of the cooling structure for a battery pack according to the present application will be described in detail.Note that the battery pack is composed of a plurality of battery cells 12 and a case 10, and other components, i.e., a plurality of battery cells 12 are sequentially stacked and connected via the bus bar 13 to form a cell module 11, and the plurality of cell modules 11 are connected to the case 10 and other components to form the battery pack. The above structure is prior art and therefore will not be described again. In order to make the description of the cooling structure clearer and more specific, in the present embodiment, as shown in FIG. 1, only two cell modules 11 are illustrated (i.e., the number of cell modules 11 in the battery pack is not limited, and this should be determined based on the actual usage requirements, etc.), and busbars 13 are provided on both sides of each group of battery cells 12 in the stacking direction (i.e., at both ends in the width direction of the cell mode 11).Specifically, as shown in FIGS. 1 to 6, the first cooling plate 21 is disposed on the upper surface of the lower case 10 of the battery pack, and may be joined to the lower case 10 by welding or bolting (after connection, the coolant flow may not be affected). The above-mentioned cell module 11 is disposed on the upper surface of the first cooling plate 21 so that the first cooling plate 21 can fit on the lower surface of the cell module 11, facilitating the heat dissipation effect of the battery cell 12. The size, shape, etc. of the first cooling plate 21 are not particularly limited as long as it can achieve a heat dissipation effect for all the battery cells 12 in the battery pack, i.e., the cell modules 11 in the battery pack should be disposed on the upper surface of the first cooling plate 21.Moreover, a plurality of flow passages are formed in the first cooling plate 21 to improve the order of the coolant flow and thereby more effectively achieve the heat dissipation effect of the present cooling structure. As shown in FIG. 7, in this embodiment, a plurality of third cavities 210 are provided inside the first cooling plate 21 to form the plurality of flow passages. Moreover, a plurality of first communication holes 211 are provided on the upper surface of the first cooling plate 21 to respectively connect the flow passages to the liquid inlet port 31, the liquid outlet port 32, and the second cooling plate 22. Note that the size, cross-sectional shape, and number of the third cavity 210 (i.e., the size, cross-sectional shape, and number of flow channels) are not particularly limited, and should be comprehensively determined based on the actual situation as long as the coolant can flow through each second cooling plate 22 and the bottom of each cell module 11 to meet the heat dissipation requirements of the battery pack. (For example, in this embodiment, the flow channels may allow the coolant to flow through each second cooling plate 22 in the direction indicated by the arrows in FIG. 6.) Further, although not shown in the figure, a flow channel located on the lower side of the cell module 11 may be formed into a mosquito repellent coil-like disk-shaped structure to facilitate heat dissipation of the coolant on the battery cell 12.It is further noted that there are no specific restrictions on the number, position, size, etc. of the first communication holes 211. It should be determined based on the actual situation, for example, the position and size of the liquid inlet port 31 or the liquid outlet port 32 and the size of the side plate 221 as described below, so long as the technical effect of the refrigerant pipe can be achieved.In the present embodiment, as shown in FIGS. 5 to 7, the second cooling plate 22 includes a main plate 220 shaped into a rectangular parallelepiped-like structure and two side plates 221. The main plate 220 is fixed to the side of the bus bar 13 of the cell module 11 facing away from the battery cell 12, and the length, height, etc. of the main plate 220 are matched to the bus bar 13, which better contributes to realizing the heat dissipation effect of the second cooling plate 22 on the bus bar 13; moreover, the two side plates 221 are respectively connected to two ends of the main plate 220 in the longitudinal direction. Specifically, the side plates 221 are formed with a first cavity 2211 and an opening capable of connecting the first cavity 2211 to an exterior, the opening being fitted to the main plate 220 so that both ends of the main plate 220 are longitudinally connected to the side plates 221 through the opening. In the present embodiment, in order to ensure the stability of the overall structure of the second cooling plate 22, the main plate 220 is embedded into the first cavity 2211 of the side plate 221 through the opening, and then the side plate 221 is joined to the main plate 220 by welding.Further, the second cooling plate 22 may communicate with the flow channel (i.e., the third cavity 210) of the first cooling plate 21 via the two side plates 221. Specifically, as shown in FIG. 7, the bottoms of the two side plates 211 are each formed with a second communication hole corresponding to the first communication hole 211, so that the coolant can enter the first cavity 2211 of the second cooling plate 22 through the first communication hole 211 of the flow passage and the second communication hole of the side plate 221. Moreover, a plurality of second cavities 2200 are formed inside the main plate 220 and arranged one after another along the height direction of the main plate 220, and each second cavity 2200 penetrates both ends of the main plate 220 along the longitudinal direction of the main plate 220 so that each second cavity 2200 can communicate with the first cavity 2211, i.e., the second cooling plate 22 is formed in the shape of a harmonic tube in this embodiment, this structure having high strength and low cost, and being the best choice to achieve the following technical effects more effectively. In this way, the coolant entering the first cavity 2211 can flow into the second cavity 2200, thereby realizing heat dissipation of the bus bar 13, and thereby discharging the coolant from the second cooling plate 22 through the other side plate 221 (the side plate 221 away from the liquid inlet port 31).Note that, in this embodiment, in order to prevent leakage and overflow of the coolant during inflow to (or outflow from) the second cooling plate 22, the size of the first communication hole 211 (corresponding to the side plate 221) matches the outer contour of the side plate 221, i.e., the side plate 221 is embedded in the third cavity 210 through the first communication hole 211. Moreover, the side plate 221 and the first cooling plate 21 may have an interference fit to achieve a stable connection between the second cooling plate 22 and the first cooling plate 21. It is further noted that the second cooling plate 22 and the first cooling plate 21 are vertically connected, which facilitates the flow of the coolant. Moreover, an insulating layer is sprayed and formed on the outer surface of the second cooling plate 22, and the thickness of the insulating layer is less than 0.5 mm to enhance the safety of the battery pack during use.Moreover, as shown in FIGS. 2 to 5, a support member 23 is provided between the second cooling plate 22 and the side shells 10 of the battery pack so that the second cooling plate 22 abuts on the bus bar 13, i.e., the second cooling plate 22 can be more closely attached to the bus bar 13, thereby improving heat dissipation efficiency; moreover, the support member 23 is preferably made of instant noodle material having compressive elasticity, and also has some energy absorbing effect besides supporting and fixing the second cooling plate 22.In addition, a heat conducting member 24 is provided between the second cooling plate 22 and the bus bar 13 for improving the heat dissipation effect of the second cooling plate 22, and under the action of the above-mentioned support member 23, the bus bar 13, the heat conducting member 24, and the second cooling plate 22 may abut each other in close contact one after another. In order to better achieve the above technical effects, the heat conductive member 24 should have good heat conductivity and insulation properties, but its specific material is not specified. For example, the heat conducting element 24 can consist of heat conducting silicone.According to the cooling structure for a battery pack of the present application, the coolant may flow into the flow channel of the first cooling plate 21 through the liquid inlet port 31 so that the coolant flows into the third cavity 210 of the first cooling plate 21 to achieve heat dissipation of the battery cell 12; moreover, the coolant may also flow into the second cooling plate 22 through the flow channel to dissipate heat from the bus bar 13, so that the battery can more exhibit its performance; subsequently, the heat-exchanged coolant may be dissipated through the liquid outlet port 32.Moreover, according to a second aspect of the present application, there is provided a battery pack including the above-described cooling structure for a battery pack.Finally, it should be noted that the above embodiments are merely for illustrating the technical solution of the present application but are not intended to limit the same; although the present application has been described in detail with reference to the above embodiments, it should be understood by those skilled in the art that they can still modify the technical solutions set forth in the above embodiments or make equivalent substitutions for some or all of the technical features; however, these modifications or substitutions do not lead to the gist of the respective technical solutions deviating from the scope of the technical solutions of the embodiments of the present application.Industrial applicabilityIn the cooling structure for the battery pack and a battery pack provided by the present application, the coolant may flow into the flow channel of the first cooling plate through the liquid inlet port, then flow into the second cooling plate through the flow channel, and be discharged through the liquid outlet port. In this way, the first and second cooling plates may dissipate the heat from the battery cell and the bus bar, such that the battery may better develop its performance.

Claims

A cooling structure for a battery pack, characterized in that the cooling structure for the battery pack comprises: a cooling plate assembly provided inside the battery pack, the cooling plate assembly comprising a first cooling plate and a plurality of second cooling plates connected to the first cooling plate; the first cooling plate being connected to the lower case of the battery pack, and a flow channel connected to the second cooling plate being formed inside the first cooling plate; the first cooling plate abutting against the cell modules inside the battery pack, and the second cooling plate being respectively connected to the bus bars of each of the cell modules; and a liquid inlet port and a liquid outlet port being respectively connected to the flow channel; wherein the coolant is capable of flowing through each of the second cooling plates in sequence through the inlet port and the flow channel, and being discharged through the liquid outlet port.The cooling structure for a battery pack according to claim 1, characterized in that the second cooling plate includes a main plate formed into a rectangular plate-like structure and two side plates, two of the side plates being connected to two ends of the main plate in the longitudinal direction, respectively.The cooling structure for a battery pack according to claim 2, characterized in that the side plates are formed with a first cavity and an opening capable of connecting the first cavity to an exterior, the opening being fitted to the main plate so that both ends of the main plate in the longitudinal direction are connected to the side plates through the opening.The cooling structure for a battery pack according to claim 3, characterized in that a plurality of second cavities are formed inside the main plate, which are arranged one after another in the height direction of the main plate, and each of the second cavities passes through both ends of the main plate along the longitudinal direction of the main plate, so that each of the second cavities is connected to the first cavity.The cooling structure for a battery pack according to claim 2, characterized in that a plurality of third cavities are provided inside the first cooling plate to form the plurality of flow passages; and the first cooling plate is provided with a first communication hole on the upper surface of the first cooling plate capable of respectively connecting the flow passages to the liquid inlet port, the liquid outlet port, and the second cooling plate.The cooling structure for a battery pack according to claim 5, characterized in that the second cooling plate is vertically connected to the first cooling plate, and the bottoms of the two side plates are each formed with a second communication hole corresponding to the first communication hole.The cooling structure for a battery pack according to claim 1, characterized in that a support member is provided between the second cooling plate and the side shells of the battery pack so that the second cooling plate abuts against the sink.The cooling structure for a battery pack according to claim 1, characterized in that a heat conducting member is provided between the second cooling plate and the bus bars.The cooling structure for a battery pack according to claim 1, characterized in that an insulating layer is sprayed and formed on the outer surface of the second cooling plate, the insulating layer having a thickness of less than 0.5 mm.A battery pack, characterized in that the battery pack is provided with a cooling structure for a battery pack according to any one of claims 1 to 9.

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