Battery pack

Abstract

The battery pack comprises a heat exchange device, a box body, a cover plate and a battery cell group, a containing cavity is formed in the box body, a cavity opening of the containing cavity is covered with the cover plate in a sealing mode, the battery cell group is arranged in the containing cavity, and the heat exchange device is arranged at the bottom of the battery cell group; the heat exchange device comprises a first plate body and a second plate body; the first plate body and the second plate body are arranged in a stacked mode, a groove extending in the first direction is formed in the side, facing the second plate body, of the first plate body, a protruding part is arranged on the second plate body, and the protruding part is embedded into the groove; a heat exchange cavity is formed in the position, corresponding to the protruding part, in the second plate body, and a first flow channel extending in the second direction is formed in the first plate body; the first flow channel communicates with the groove and is suitable for circulation of cooling liquid, and the cooling liquid flows through the surface of the protruding part so as to exchange heat with the refrigerant medium in the heat exchange cavity. Therefore, the temperature of the cooling liquid in the first plate body at the corresponding position can be adjusted through the cooling medium in the protruding part, and the effect of accurately adjusting the heat dissipation effect of different positions of the first plate body is achieved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of batteries, and particularly relates to a battery pack. BACKGROUND

[0002] Lithium batteries are widely used in the fields of automobiles and electronic devices due to high energy density, small internal resistance, and mature production process. However, due to the active internal chemical reaction of the lithium battery, the generated heat accumulates, and when the generated heat cannot be dissipated in time, the battery temperature continues to rise until the battery is out of control, causing a safety hazard.

[0003] In the related art, a liquid cooling plate is usually arranged at the bottom of a battery cell module in a battery pack to cool the battery cell module. However, due to different heat dissipation requirements at different positions in the battery pack, the liquid cooling plate cannot meet the differentiated heat dissipation requirements. UTILITARIAN CONTENT

[0004] The application aims to provide a battery pack that can solve the problem that the liquid cooling plate cannot meet the differentiated heat dissipation requirements due to different heat dissipation requirements at different positions in the battery pack.

[0005] To solve the above technical problem, the application is implemented as follows:

[0006] The application provides a battery pack, which comprises a heat exchange device, a box body, a cover plate, and a battery cell group. The box body is internally provided with a containing cavity, the containing cavity has a cavity opening, the cover plate covers the cavity opening, the battery cell group and the heat exchange device are arranged in the containing cavity, and the heat exchange device is arranged at the bottom of the battery cell group. The heat exchange device comprises a first plate body and a second plate body.

[0007] The first plate body and the second plate body are arranged in a laminated manner. The heat exchange device has intersecting first and second directions, and the first and second directions are both perpendicular to the laminating direction of the first plate body and the second plate body. One side of the first plate body facing the second plate body is provided with a groove extending along the first direction. The second plate body is provided with a corresponding protruding portion, and the protruding portion is embedded in the groove.

[0008] The second plate body is provided with a heat exchange cavity at a position corresponding to the protruding portion. The heat exchange cavity is adapted to flow through a refrigerant medium.

[0009] The first plate body is provided with a first flow channel extending along the second direction, and the second direction intersects the first direction. The first flow channel is in communication with the groove. The first flow channel is adapted to flow through a cooling liquid, and the cooling liquid flows through the surface of the protruding portion to exchange heat with the refrigerant medium in the heat exchange cavity.

[0010] Optionally, the first plate has a plurality of grooves arranged at intervals along the second direction, and the second plate has a protrusion at a corresponding position of each groove;

[0011] The first plate has a plurality of first flow channels arranged at intervals along the first direction, and each first flow channel is connected to a plurality of the grooves.

[0012] Optionally, the first plate includes a substrate and a plurality of first partitions;

[0013] The substrate has a hollow cavity, and a plurality of first partitions are spaced apart in the hollow cavity along the first direction to form a plurality of first flow channels in the hollow cavity;

[0014] The heat exchange device also has a third direction, which is perpendicular to the first direction and the second direction respectively. The substrate has a first side and a second side disposed opposite to each other along the third direction. The second side is connected to the second plate body. The groove is disposed in the second side, and the first partition is disconnected at the groove.

[0015] Optionally, the first side is provided with an inlet and an outlet, which are respectively connected to the first flow channel.

[0016] Optionally, the heat exchange cavity is provided with a second partition, which divides the heat exchange cavity into a second flow channel and a third flow channel extending along the first direction; the second flow channel is located inside the protrusion, and the third flow channel is located on the side of the second flow channel away from the first plate; the second partition is provided with a connecting port, which connects the second flow channel and the third flow channel.

[0017] Optionally, the heat exchange device further includes an input pipe and an output pipe, the input pipe and the output pipe being respectively disposed on both sides of the second plate along the first direction, one end of the third flow channel being connected to the input pipe, and the other end of the third flow channel being connected to the output pipe.

[0018] Optionally, the heat exchange device further includes a regulating valve located between the third flow channel and the input pipeline; and / or, the regulating valve located between the third flow channel and the output pipeline, the regulating valve being used to regulate the flow rate of the cold medium in the third flow channel.

[0019] Optionally, the first plate body has a heat-conducting surface on the side opposite to the second plate body, and the battery cell assembly is disposed on the heat-conducting surface; the battery cell assembly includes a plurality of battery cells arranged in a row, and each groove corresponds to a row of battery cells.

[0020] Optionally, the heat exchange cavity is provided with a second partition, which divides the heat exchange cavity into a second flow channel and a third flow channel. The second partition is provided with a plurality of connecting ports, which connect the second flow channel and the third flow channel. Each connecting port corresponds to at least one battery cell.

[0021] Optionally, the battery pack further includes a thermally conductive adhesive layer, which is disposed between the bottom of the battery cell assembly and the first plate.

[0022] And / or, the battery pack further includes a heat insulation layer disposed between the second plate and the inner wall of the housing.

[0023] In this application, a first plate and a second plate are stacked, with a protrusion on the second plate embedded in a groove in the first plate. A first flow channel is provided in the first plate, and a heat exchange chamber is provided in the second plate at a position corresponding to the protrusion. This allows coolant to be introduced into the first plate and a refrigerant to be introduced into the second plate. When the coolant flows in the first flow channel, it flows over the surface of the portion of the protrusion embedded in the groove, allowing heat exchange between the coolant and the refrigerant in the heat exchange chamber of the protrusion. This refrigerant in the protrusion can regulate the temperature of the coolant in the first plate at corresponding positions, achieving precise adjustment of the heat dissipation effect at different locations on the first plate. Thus, when the heat exchange device is applied to a battery pack, the first plate is thermally connected to the battery cells in the battery pack. The second plate can then precisely adjust the heat dissipation effect at different locations on the first plate, meeting the differentiated heat dissipation needs of different locations within the battery cells and helping to improve the temperature uniformity within the battery pack.

[0024] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, specific embodiments of this application are given below. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the accompanying drawings used in the description of the embodiments will be briefly introduced below, wherein:

[0026] Figure 1 This is a schematic diagram of a heat exchange device according to an embodiment of this application;

[0027] Figure 2 This is one of the exploded views of a heat exchange device according to an embodiment of this application;

[0028] Figure 3 This is a second exploded view of a heat exchange device according to an embodiment of this application;

[0029] Figure 4 This is a schematic diagram of the first plate body according to an embodiment of this application from one perspective;

[0030] Figure 5 This is a schematic diagram of the first plate body according to an embodiment of this application from another perspective;

[0031] Figure 6 This is a partial structural schematic diagram of the first plate body according to an embodiment of this application;

[0032] Figure 7 This is a cross-sectional view of the first plate body according to an embodiment of this application;

[0033] Figure 8 This is a schematic diagram of the second plate body according to an embodiment of this application from one perspective;

[0034] Figure 9 This is a schematic diagram of the second plate body according to an embodiment of this application from another perspective;

[0035] Figure 10 This is one of the cross-sectional views of the second plate body corresponding to the protrusion according to an embodiment of this application;

[0036] Figure 11 This is a second cross-sectional view of the second plate body corresponding to the protrusion according to an embodiment of this application;

[0037] Figure 12 This is a schematic diagram of the heat exchange principle between the first plate and the second plate according to an embodiment of this application;

[0038] Figure 13 This is a schematic diagram of the mating structure of the first plate and the second plate according to an embodiment of this application;

[0039] Figure 14 This is an exploded view of a battery pack according to an embodiment of this application.

[0040] Figure label:

[0041] 1: Heat exchange device; 10: First plate; 101: Groove; 102: First flow channel; 104: Inlet; 105: Outlet; 11: Substrate; 11a: First side; 11b: Second side; 12: First partition; 10a: Hollow cavity; 20: Second plate; 201: Protrusion; 202: Heat exchange chamber; 21: Second partition; 211: Second flow channel; 212: Third flow channel; 213: Connecting port; 22: Input pipe; 23: Output pipe; 24: Regulating valve; 2: Housing; 2a: Receiving cavity; 3: Cover plate; 4: Battery cell assembly; 41: Battery cell; 5: Thermally conductive adhesive layer; 6: Thermal insulation layer; X: First direction; Y: Second direction; Z: Third direction. Detailed Implementation

[0042] The embodiments of this application will now be described in detail. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0043] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise stated, "multiple" means two or more. Furthermore, "and / or" in the specification and claims indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0044] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0045] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0046] Before providing a detailed explanation of the heat exchange device and battery pack provided in the embodiments of this application, the application scenarios of the heat exchange device and battery pack will be specifically described first:

[0047] Currently, there are four main cooling methods for power batteries: natural cooling, air cooling, liquid cooling, and direct cooling. As the capacity and energy of power batteries continue to increase, ensuring that the battery pack can operate normally within its operating temperature range has become increasingly important. Of these four cooling methods, natural cooling and air cooling have been gradually phased out by the industry due to their low heat exchange efficiency, complex space design, low space utilization, and high sealing performance requirements. Liquid cooling and direct cooling technologies have become the preferred cooling methods for power batteries. However, current liquid cooling and direct cooling technologies face the following challenges:

[0048] In practical applications, when using liquid cooling for high-capacity power batteries, the temperature at both ends of the battery module is often low, while the temperature in the central area is high, resulting in a large temperature difference and poor temperature uniformity across the entire battery pack. To improve the temperature uniformity of the liquid cooling system, it is necessary to design more complex liquid cooling channels, focusing on the differences between the high and low temperature regions of the battery, which increases the design and manufacturing difficulty.

[0049] Compared to liquid cooling technology, direct cooling technology has higher heat exchange efficiency, but its cooling / heating degree is difficult to control precisely, which affects the temperature uniformity of the battery. Therefore, it is often necessary to add a temperature uniformity structure to ensure the cooling effect of direct cooling.

[0050] Based on the above problems, this application provides a battery pack in which the heat exchange device adopts a composite cold plate structure, with a liquid cooling plate as the cooling substrate of the power battery. The direct cooling plate and the liquid cooling plate are stacked together, and the temperature of the medium in the liquid cooling plate is regulated by the direct cooling plate to ensure that the temperature difference of the liquid cooling plate is reduced in the whole area, thereby helping to improve the overall temperature uniformity of the battery pack.

[0051] The battery pack provided in this application will be described in detail below with reference to the accompanying drawings, through specific embodiments and application scenarios.

[0052] like Figures 1 to 3 As shown, a battery pack according to some embodiments of this application includes a heat exchange device 1, a housing 2, a cover plate 3, and a battery cell assembly 4. The housing 2 is provided with a receiving cavity 2a, which has an opening. The cover plate 3 covers the opening. The battery cell assembly 4 and the heat exchange device 1 are both disposed in the receiving cavity 2a, and the heat exchange device 1 is disposed at the bottom of the battery cell assembly 4.

[0053] The heat exchange device 1 includes a first plate 10 and a second plate 20. The first plate 10 and the second plate 20 are stacked. The heat exchange device 1 has a first direction X, a second direction Y, and a third direction Z. The third direction Z is parallel to the stacking direction of the first plate 10 and the second plate 20. The first direction X and the second direction Y intersect and are both perpendicular to the third direction Z. The first plate 10 has a groove 101 extending along the first direction X on the side facing the second plate 20. The second plate 20 has a corresponding protrusion 201, which is embedded in the groove 101. A heat exchange cavity 202 is provided in the second plate 20 at a position corresponding to the protrusion 201 (e.g., ...). Figure 10 As shown), the heat exchange cavity 202 is suitable for flowing with a cold medium; the first plate 10 is provided with a first flow channel 102 extending along the second direction Y (as shown). Figure 6 (As shown); the first flow channel 102 is connected to the groove 101. The first flow channel 102 is suitable for the flow of coolant, and the coolant flows over the surface of the protrusion 201 to exchange heat with the cold medium in the heat exchange chamber 202.

[0054] In this embodiment, a first plate 10 and a second plate 20 are stacked, with a protrusion 201 on the second plate 20 embedded in a groove 101 in the first plate 10. A first flow channel 102 is provided in the first plate 10, and a heat exchange chamber 202 is provided in the second plate 20 at a position corresponding to the protrusion 201. This allows coolant to be introduced into the first plate 10 and a cooling medium to be introduced into the second plate 20. When the coolant flows in the first flow channel 102, it flows over the surface of the portion of the protrusion 201 embedded in the groove 101, allowing heat exchange between the coolant and the cooling medium in the heat exchange chamber 202 of the protrusion 201. This allows the cooling medium in the protrusion 201 to be used to adjust the temperature of the coolant in the first plate 10 at corresponding positions, achieving precise adjustment of the heat dissipation effect at different positions of the first plate 10. In this way, when the heat exchange device 1 is applied to the battery pack, the first plate 10 is thermally connected to the battery cell group 4 in the battery pack. Then, the heat dissipation effect of different positions of the first plate 10 can be precisely adjusted by the second plate 20 to meet the differentiated heat dissipation requirements of different positions of the battery cell group 4, which helps to improve the temperature uniformity in the battery pack.

[0055] It is understood that the heat exchange device 1 of this application embodiment can be applied to cooling a battery pack. The battery pack includes a cell assembly 4, which is formed by stacking multiple cells 41 in a certain arrangement. The cell assembly 4 can be thermally connected to the first plate 10 in the heat exchange device 1, so that the coolant in the first plate 10 can exchange heat with the cells 41 in the cell assembly 4, thereby achieving the cooling or heating effect on the cells 41.

[0056] Specifically, the heat exchange device 1 includes a first plate 10 and a second plate 20, which are stacked together. The first plate 10 has a groove 101 on the side facing the second plate 20, and the second plate 20 covers the opening of the groove 101 to ensure the sealing of the groove 101. At the same time, a first flow channel 102 is provided in the first plate 10, which communicates with the groove 101 so that the coolant in the first flow channel 102 can flow through the groove 101.

[0057] Furthermore, the second plate 20 has a protrusion 201 at a position corresponding to the groove 101. The protrusion 201 extends into the groove 101, and a gap exists between the surface of the protrusion 201 and the inner wall of the groove 101 so that the coolant in the first flow channel 102 can flow through the surface of the protrusion 201 in the groove 101. A heat exchange chamber 202 is provided in the second plate 20 at a position corresponding to the protrusion 201. The heat exchange chamber 202 is at least partially located within the protrusion 201, and a cooling medium can be introduced into the heat exchange chamber 202.

[0058] It is understood that this application employs a composite cold plate structure, introducing coolant into the first plate 10 for liquid cooling and introducing a cooling medium into the second plate 20 for direct cooling. This allows the protrusions 201 in the second plate 20 to embed into the first plate 10. The cooling medium in the second plate 20 can exchange heat with the coolant in the first plate 10 at the locations of the protrusions 201, thereby regulating the coolant temperature. In practical applications, the position and number of protrusions 201 in the second plate 20 can be flexibly set according to the temperature distribution of the workpiece (e.g., a battery cell assembly) thermally connected to the first plate 10, thus adjusting the temperature uniformity of the coolant flowing in the first plate 10.

[0059] Both the first plate 10 and the second plate 20 can be manufactured using an extrusion molding process, and the first plate 10 and the second plate 20 can be fixed together by welding. Of course, the first plate 10 and the second plate 20 can be manufactured using other processing methods, and this embodiment of the application does not limit the specific methods used.

[0060] It should be noted that the first direction X and the second direction Y are both perpendicular to the stacking direction of the first plate 10 and the second plate 20. However, the perpendicularity does not mean absolute perpendicularity. The first direction X and the second direction Y can be perpendicular or approximately perpendicular to the stacking direction of the first plate 10 and the second plate 20.

[0061] Optionally, such as Figure 2 , Figure 3 and Figure 6As shown, the first plate 10 is provided with a plurality of grooves 101 arranged at intervals along the second direction Y, and the second plate 20 is provided with a protrusion 201 at the corresponding position of each groove 101; the first plate 10 is provided with a plurality of first channels 102 arranged at intervals along the first direction X, and each first channel 102 is connected to a plurality of grooves 101.

[0062] In this embodiment, by providing a plurality of grooves 101 spaced apart along the second direction Y in the first plate 10, correspondingly, a plurality of protrusions 201 are provided in the second plate 20, each protrusion 201 being embedded in a corresponding groove 101. Furthermore, a plurality of first flow channels 102 spaced apart along the first direction X are provided in the first plate 10, such that each first flow channel 102 simultaneously communicates with a plurality of grooves 101. Figure 10 As shown, the second plate 20 has a heat exchange chamber 202 at the corresponding position of each protrusion 201. In this way, when the coolant in the first plate 10 flows through the multiple first flow channels 102, it will flow over the surface of the multiple protrusions 201. The coolant exchanges heat with the cold medium at the protrusions 201. Therefore, by controlling the temperature or flow rate of the cold medium in the heat exchange chamber 202 in each protrusion 201, the temperature of different positions of the first plate 10 can be precisely adjusted.

[0063] Optionally, such as Figures 4 to 7 As shown, the first plate 10 includes a substrate 11 and a plurality of first partitions 12; a hollow cavity 10a is provided inside the substrate 11, and the plurality of first partitions 12 are spaced apart along a first direction X in the hollow cavity 10a to form a plurality of first flow channels 102 in the hollow cavity 10a; the heat exchange device 1 also has a third direction Z, which is perpendicular to the first direction X and the second direction Y respectively. The substrate 11 has a first side surface 11a and a second side surface 11b disposed opposite to each other along the third direction Z. The second side surface 11b is connected to the second plate 20, and a groove 101 is provided in the second side surface 11b, and the first partitions 12 are disconnected at the groove 101. The third direction Z is also the stacking direction of the first plate 10 and the second plate 20.

[0064] In this embodiment, multiple spaced-apart first partitions 12 are provided in the hollow cavity 10a of the substrate 11 to form multiple first flow channels 102. A groove 101 is provided on the side of the substrate 11 facing the second plate 20, and the first partitions 12 are broken at the groove 101 so that the protrusions 201 of the second plate 20 can be embedded in the substrate 11. This allows the coolant in the first flow channels 102 to flow over the surface of the protrusions 201, thereby achieving heat exchange with the cooling medium. The first plate 10 of this application has a simple structure and is easy to process. It is also easy to cooperate with the second plate 20 to use the cooling medium in the second plate 20 to regulate the temperature of the coolant in the first plate 10.

[0065] In a specific application, the side surface of the substrate 11 facing away from the second plate 20, that is, the first side surface 11a, can be thermally connected to the battery cell assembly 4 in the battery pack so that the coolant can exchange heat with the battery cell assembly 4 when flowing in the first plate 10, thereby achieving the cooling or heating effect on the battery cell assembly 4.

[0066] Optionally, such as Figure 4 and Figure 7 As shown, the first side 11a is provided with an inlet 104 and an outlet 105, which are respectively connected to the first flow channel 102.

[0067] In this embodiment, an inlet 104 and an outlet 105 are provided in the first side surface 11a of the substrate 11. The inlet 104 and the outlet 105 are respectively connected to an external coolant circulation system. This allows coolant to be introduced into the hollow cavity 10a of the substrate 11 via the inlet 104 and discharged from the hollow cavity 10a via the outlet 105, thereby achieving circulation of coolant within the substrate 11. Simultaneously, the inlet 104 and the outlet 105 are located on the side of the substrate 11 opposite to the second plate 20 to avoid interference with the structural layout of the second plate 20.

[0068] Optionally, such as Figure 10 , Figure 11 As shown, a second partition 21 is provided inside the heat exchange chamber 202, which divides the heat exchange chamber 202 into a second flow channel 211 and a third flow channel 212 extending along the first direction X. The second flow channel 211 is located inside the protrusion 201, and the third flow channel 212 is located on the side of the second flow channel 211 away from the first plate 10. A connecting port 213 is provided in the second partition 21, which connects the second flow channel 211 and the third flow channel 212.

[0069] In this embodiment, a second baffle 21 is provided inside the heat exchange cavity 202 to divide the heat exchange cavity 202 into a second flow channel 211 and a third flow channel 212 that are separated from each other. The second flow channel 211 is located inside the protrusion 201, and the second flow channel 211 is connected to the third flow channel 212 through a communication port 213 in the second baffle 21. Furthermore, the third flow channel 212 can be connected to an external cold medium supply system. When the cold medium enters the second plate 20, it first enters the third flow channel 212 and then the second flow channel 211. In this way, the flowing cold medium, after passing through the convergence and buffering effect of the third flow channel 212, can ensure that the cold medium enters the second flow channel 211 more smoothly and evenly, thereby improving the heat exchange effect at the protrusion 201.

[0070] Specifically, such as Figure 12 and Figure 13 As shown, the first plate 10 and the second plate 20 are stacked in the third direction Z. The second plate 20 has multiple protrusions 201, and a heat exchange cavity 202 is formed at a corresponding position of each protrusion 201. Furthermore, a second partition 21 is provided in each heat exchange cavity 202, which divides the heat exchange cavity 202 into two layers of flow channels spaced apart along the third direction Z. The second flow channel 211 is located within the protrusion 201, and the third flow channel 212 is located on the side of the second flow channel 211 opposite to the first plate 10. Both the second flow channel 211 and the third flow channel 212 extend along the first direction X. At least one connecting port 213 is provided in the second partition 21, connecting the second flow channel 211 and the third flow channel 212. The third flow channel 212 is used to connect with an external cold medium supply system.

[0071] Then, the cold medium is introduced into the third flow channel 212 through the input pipe 22, and then enters the second flow channel 211 through the connecting port 213. During the flow of the cold medium in the second flow channel 211, it will exchange heat with the coolant flowing through the surface of the protrusion 201 in the first flow channel 102, thereby realizing the heat exchange between the first plate 10 and the second plate 20.

[0072] In some embodiments, the second partition 21 is provided with a plurality of communication ports 213, which are spaced apart along the first direction X. The spacing between two adjacent communication ports 213 may be the same or different. The size of the communication ports 213 can be flexibly set according to the heat exchange requirements, and this embodiment does not limit this.

[0073] In specific applications, the position of the connecting port 213 in the second partition 21 can also be set according to the position of the battery cell 41 that is thermally connected to the first plate 10. Specifically, the side of the first plate 10 away from the second plate 20 is used to set the battery cell group 4, which includes a plurality of battery cells 41 arranged in a row. Therefore, the position of the connecting port 213 in the second partition 21 can be set to correspond to the position of the battery cell 41, that is, the orthographic projection of the battery cell 41 along the third direction Z and the orthographic projection of the connecting port 213 along the third direction Z at least partially coincide.

[0074] It is understandable that the heat exchange effect is better at the connection port 213 because the fluidity of the cold medium is relatively high. Therefore, by setting the position of the connection port 213 to correspond to the position of the battery cell 41, the heat exchange effect between the heat exchange device 1 and the battery cell 41 can be improved.

[0075] Optionally, such as Figures 8 to 10 As shown, the heat exchange device 1 also includes an input pipe 22 and an output pipe 23. The input pipe 22 and the output pipe 23 are respectively located on both sides of the second plate 20 along the first direction X. One end of the third flow channel 212 is connected to the input pipe 22, and the other end of the third flow channel 212 is connected to the output pipe 23.

[0076] In this embodiment, an input pipe 22 and an output pipe 23 are provided on both sides of the second plate 20 along the first direction X, and the two ends of the third flow channel 212 are respectively connected to the input pipe 22 and the output pipe 23. The input pipe 22 and the output pipe 23 can be connected to an external cold medium supply system so that the cold medium can be introduced into the third flow channel 212 through the input pipe 22 and the cold medium in the third pipe can be discharged through the output pipe 23, thereby ensuring the circulation of the cold medium in the second plate 20 and realizing the heat exchange with the first plate 10.

[0077] Specifically, the second plate 20 is provided with a plurality of protrusions 201, and each protrusion 201 is provided with a second flow channel 211 and a third flow channel 212 at a corresponding position. Furthermore, all the third flow channels 212 are connected to the input pipe 22 and the output pipe 23. In this way, the input pipe 22 can be used to introduce the cold medium into the plurality of third flow channels 212 respectively, and the output pipe 23 can be used to export the cold medium in the plurality of third flow channels 212 respectively.

[0078] Optionally, such as Figure 8 As shown, the heat exchange device 1 also includes a regulating valve 24, which is located between the third flow channel 212 and the inlet pipe 22; and / or, the regulating valve 24 is located between the third flow channel 212 and the outlet pipe 23, and is used to regulate the flow rate of the cold medium in the third flow channel 212. The regulating valve 24 can be a flow regulating valve 24.

[0079] In this embodiment of the application, by setting a regulating valve 24 between the third flow channel 212 and the input pipe 22 and / or the output pipe 23, the flow rate of the cold medium in the third flow channel 212 can be adjusted by the regulating valve 24, thereby accurately adjusting the heat exchange effect at the corresponding protrusion 201, which helps to improve the precise adjustment of the temperature uniformity of the first plate 10.

[0080] In practical applications, the second plate 20 is provided with multiple protrusions 201, each protrusion 201 having a corresponding second flow channel 211 and a third flow channel 212, and a regulating valve 24 is provided for each third flow channel 212. The flow rate of the cooling medium in the corresponding third flow channel 212 can be individually adjusted through each regulating valve 24. Therefore, the flow rate of the cooling medium in the corresponding third flow channel 212 can be adjusted according to the heat exchange requirements of different areas of the first plate 10, thereby achieving differentiated regulation and control.

[0081] Understandably, when the heat exchange device 1 is used in the battery pack to cool the cell assembly 4, the temperature in the middle area of ​​the cell assembly 4 is generally higher and the temperature in the edge area is relatively lower due to the arrangement structure of the cell assembly 4. Therefore, by controlling the opening and closing degree of the regulating valve 24, the flow path of the cold medium in the third flow channel 212 corresponding to the middle area of ​​the cell assembly 4 can be made larger than the flow path of the cold medium in the third flow channel 212 corresponding to the edge area of ​​the cell assembly 4, thereby meeting the differentiated cooling requirements.

[0082] In some embodiments, a temperature measuring element and a control element may also be provided in the battery pack. The temperature measuring element is used to detect the temperature at different locations of the cell assembly 4. The control element is electrically connected to the temperature measuring element and multiple regulating valves 24 respectively. Then, the control element can accurately control the opening and closing of different regulating valves 24 based on the temperature distribution detected by the temperature measuring element, thereby regulating and controlling the flow distribution of the cold medium at different locations in the second plate 20, thereby improving the temperature uniformity of the cell assembly 4.

[0083] Optionally, such as Figure 14 As shown, the first plate 10 has a heat-conducting surface on the side opposite to the second plate 20, and the battery cell group 4 is disposed on the heat-conducting surface. The battery cell group 4 includes a plurality of battery cells 41 arranged in rows, and each groove 101 corresponds to a row of battery cells 41.

[0084] In this embodiment of the application, by making each groove 101 in the first plate 10 correspond to a row of battery cells 41, that is, the second plate 20 is provided with a protrusion 201 at the corresponding position of each row of battery cells 41, it is convenient to use the cold medium in the protrusion 201 to accurately adjust the temperature of the coolant in the first plate 10 at the corresponding position, thereby achieving precise control of the cooling effect of the battery cells 41.

[0085] Specifically, the battery pack housing 2 has a receiving cavity 2a, and the battery cell assembly 4 and the heat exchange device 1 are both located in the receiving cavity 2a. The heat exchange device 1 is located at the bottom of the receiving cavity 2a. The battery cell assembly 4 is located on the side of the first plate 10 away from the second plate 20. The first plate 10 is thermally connected to the battery cell assembly 4. Thus, the first plate 10 can be used to cool or heat the battery cell assembly 4. At the same time, the temperature of the coolant in the first plate 10 can be adjusted by the cold medium in the second body, thereby ensuring the temperature uniformity of the battery cell assembly 4.

[0086] It is understood that each groove 101 corresponds to a row of cells 41, meaning that the orthographic projection of the groove 101 along the third direction Z at least partially overlaps with the orthographic projection of the row of cells 41.

[0087] In some embodiments, the battery cell 41 includes a height direction, a thickness direction, and a width direction. A first direction X is parallel to the width direction of the battery cell 41, a second direction Y is parallel to the thickness direction of the battery cell 41, and a third direction Z is parallel to the height direction of the battery cell 41. Furthermore, a plurality of battery cells 41 arranged along the first direction X form a row of battery cells 41, each row of battery cells 41 corresponding to a groove 101, and the spacing between two adjacent rows of grooves 101 is adapted to the spacing between two adjacent rows of battery cells 41.

[0088] Optionally, such as Figure 10 and Figure 14 As shown, a second partition 21 is provided in the heat exchange cavity 202. The second partition 21 divides the heat exchange cavity 202 into a second flow channel 211 and a third flow channel 212. The second partition 21 is provided with a plurality of connecting ports 213, which connect the second flow channel 211 and the third flow channel 212. Each connecting port 213 corresponds to at least one battery cell 41.

[0089] In this embodiment, by aligning the connection port 213 in the second partition 21 with the battery cell 41, the heat exchange effect is better at the connection port 213 because the fluidity of the cold medium is relatively high. Therefore, by setting the position of the connection port 213 to correspond with the position of the battery cell 41, the heat exchange effect between the heat exchange device 1 and the battery cell 41 is improved.

[0090] In some embodiments, the correspondence between the connection port 213 and the battery cell 41 means that the orthographic projection of the connection port 213 along the third direction Z at least partially coincides with the orthographic projection of the corresponding battery cell 41. One connection port 213 may correspond to one battery cell 41, or one connection port 213 may correspond to at least two battery cells 41 simultaneously.

[0091] Optionally, such as Figure 14As shown, the battery pack also includes a thermally conductive adhesive layer 5, which is disposed between the bottom of the cell assembly 4 and the first plate 10. By providing the thermally conductive adhesive layer 5 between the bottom of the cell assembly 4 and the first plate 10, the thermally conductive adhesive layer 5 can be used to connect and fix the cell assembly 4 and the first plate 10, and can also play a role in heat conduction between the cell assembly 4 and the first plate 10.

[0092] The thermally conductive adhesive layer 5 can be made of thermally conductive adhesive, such as silicone thermally conductive adhesive, epoxy resin thermally conductive adhesive, polyurethane adhesive, polyurethane thermally conductive adhesive, etc. Those skilled in the art can flexibly select according to actual needs, and there is no limitation here.

[0093] Optionally, such as Figure 14 As shown, the battery pack also includes a heat insulation layer 6, which is disposed between the second plate 20 and the inner wall of the housing 2. By providing the heat insulation layer 6 between the second plate 20 and the inner wall of the housing 2, heat conduction between the second plate 20 and the housing 2 is isolated, reducing the energy loss of the second plate 20 and improving the heat exchange effect of the heat exchange device 1 on the cell assembly 4.

[0094] The insulation layer 6 can be made of insulation materials, such as fiberglass, asbestos, rock wool, foam materials, etc. Those skilled in the art can flexibly choose according to actual needs, and there is no limitation here.

[0095] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0096] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A battery pack, comprising a heat exchange device (1), a housing (2), a cover plate (3), and a battery cell assembly (4), wherein the housing (2) is provided with a receiving cavity (2a), the receiving cavity (2a) has an opening, the cover plate (3) is sealed at the opening, the battery cell assembly (4) and the heat exchange device (1) are both disposed in the receiving cavity (2a), and the heat exchange device (1) is disposed at the bottom of the battery cell assembly (4); Its features are, The heat exchange device (1) includes: a first plate (10) and a second plate (20); The first plate (10) and the second plate (20) are stacked together. The heat exchange device (1) has intersecting first direction (X) and second direction (Y), and both the first direction (X) and the second direction (Y) are perpendicular to the stacking direction of the first plate (10) and the second plate (20). The first plate (10) has a groove (101) extending along the first direction (X) on the side facing the second plate (20). The second plate (20) has a corresponding protrusion (201) embedded in the groove (101). The second plate (20) has a heat exchange cavity (202) at a position corresponding to the protrusion (201), and the heat exchange cavity (202) is suitable for circulating a cold medium. The first plate (10) is provided with a first flow channel (102) extending along the second direction (Y). The first flow channel (102) communicates with the groove (101). The first flow channel (102) is adapted to flow coolant, and the coolant flows over the surface of the protrusion (201) to exchange heat with the cold medium in the heat exchange chamber (202).

2. The battery pack according to claim 1, characterized in that, The first plate (10) is provided with a plurality of grooves (101) arranged at intervals along the second direction (Y), and the second plate (20) is provided with a protrusion (201) at a corresponding position of each groove (101); The first plate (10) is provided with a plurality of first flow channels (102) arranged at intervals along the first direction (X), and each first flow channel (102) is connected to a plurality of the grooves (101).

3. The battery pack according to claim 2, characterized in that, The first plate (10) includes a substrate (11) and a plurality of first partitions (12); The substrate (11) has a hollow cavity (10a) and a plurality of first partitions (12) are spaced apart in the hollow cavity (10a) along the first direction (X) to form a plurality of first flow channels (102) in the hollow cavity (10a). The heat exchange device (1) also has a third direction (Z), which is perpendicular to the first direction (X) and the second direction (Y). The substrate (11) has a first side (11a) and a second side (11b) disposed opposite to each other along the third direction (Z). The second side (11b) is connected to the second plate (20). The groove (101) is disposed in the second side (11b), and the first partition (12) is disconnected at the groove (101).

4. The battery pack according to claim 3, characterized in that, The first side (11a) is provided with an inlet (104) and an outlet (105), and the inlet (104) and the outlet (105) are respectively connected to the first flow channel (102).

5. The battery pack according to any one of claims 1-4, characterized in that, The heat exchange cavity (202) is provided with a second partition (21), which divides the heat exchange cavity (202) into a second flow channel (211) and a third flow channel (212) extending along the first direction (X). The second flow channel (211) is located in the protrusion (201), and the third flow channel (212) is located on the side of the second flow channel (211) away from the first plate (10). The second partition (21) is provided with a connecting port (213), which connects the second flow channel (211) and the third flow channel (212).

6. The battery pack according to claim 5, characterized in that, The heat exchange device (1) further includes an input pipe (22) and an output pipe (23). The input pipe (22) and the output pipe (23) are respectively disposed on both sides of the second plate (20) along the first direction (X). One end of the third flow channel (212) is connected to the input pipe (22), and the other end of the third flow channel (212) is connected to the output pipe (23).

7. The battery pack according to claim 6, characterized in that, The heat exchange device (1) further includes a regulating valve (24), which is located between the third flow channel (212) and the input pipe (22); and / or, the regulating valve (24) is located between the third flow channel (212) and the output pipe (23), and the regulating valve (24) is used to regulate the flow rate of the cold medium in the third flow channel (212).

8. The battery pack according to any one of claims 1-4, characterized in that, The first plate (10) has a heat-conducting surface on the side away from the second plate (20), and the battery cell group (4) is disposed on the heat-conducting surface; the battery cell group (4) includes a plurality of battery cells (41) arranged in a row, and each groove (101) corresponds to a row of battery cells (41).

9. The battery pack according to claim 8, characterized in that, The heat exchange cavity (202) is provided with a second partition (21), which divides the heat exchange cavity (202) into a second flow channel (211) and a third flow channel (212). The second partition (21) is provided with a plurality of connecting ports (213), which connect the second flow channel (211) and the third flow channel (212). Each connecting port (213) corresponds to at least one battery cell (41).

10. The battery pack according to any one of claims 1-4, characterized in that, The battery pack also includes a thermally conductive adhesive layer (5), which is disposed between the bottom of the battery cell assembly (4) and the first plate (10); And / or, the battery pack further includes a heat insulation layer (6) disposed between the second plate (20) and the inner wall of the housing (2).

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