Battery pack

Abstract

The utility model belongs to the technical field of batteries, and discloses a battery pack. The battery pack specifically comprises a cooling plate assembly and a plurality of battery cell modules stacked from top to bottom, the cooling plate assembly is arranged between every two adjacent battery cell modules, and the cooling plate assembly comprises a first cooling plate and a second cooling plate; the first cooling plate supports the bottom of the upper battery cell module in the two adjacent battery cell modules, and the second cooling plate covers the top of the lower battery cell module in the two adjacent battery cell modules; the mechanical strength of the first cooling plate is greater than the mechanical strength of the second cooling plate. According to the battery pack, the multiple layers of battery cells can be well cooled, the cooling effect is better, the function of improving the bearing capacity of the cooling system can be achieved at low cost, and the cooling and heat dissipation effects are not affected.

Description

TECHNICAL FIELD

[0001] The utility model relates to battery technology field especially relates to a battery pack. BACKGROUND

[0002] With the gradual development of new energy automobile industry, not only electric passenger cars begin to be applied, more electric commercial vehicles will appear in the near future, such as pure electric truck, pure electric truck and even pure electric heavy truck. Due to the difference of whole vehicle structure, the battery pack of the current passenger car is assembled by single layer of battery cell, so that only single layer of cold plate or side liquid cooling mode can meet the normal work of the battery pack. However, since the commercial vehicle cannot directly install the battery pack on the chassis of the automobile, but only can be hung on the automobile's girder, the battery pack often needs three or even four layers of battery cells to be stacked to meet the use demand of electric quantity, so that a three or four layer liquid cooling system needs to be adapted. The current liquid cooling system cannot adapt to the cooling demand of multi-layer battery cells, and can only meet the cooling of single layer of battery cells. The cooling effect of the battery cells in the middle layer of the multi-layer battery cells is poor, which leads to the continuous accumulation of heat in the middle layer battery cells and finally causes high temperature failure phenomenon, reduces the cycle life of the battery cells, and has great safety risk.

[0003] Therefore, it is urgent to provide a battery pack to solve the above technical problems in the prior art. UTILITY MODEL CONTENT

[0004] The utility model aims at providing a battery pack, which can cool multi-layer battery cells, improve the cooling effect of the battery cell modules in the middle part of the multi-layer battery cells, and improve the use reliability and service life of the multi-layer battery cells.

[0005] To achieve this purpose, the utility model adopts the following technical solutions:

[0006] The battery pack specifically comprises a cooling plate assembly and a plurality of battery cell modules stacked from top to bottom, and the cooling plate assembly is arranged between two adjacent battery cell modules, wherein: the cooling plate assembly comprises a first cooling plate and a second cooling plate, the first cooling plate supports the bottom of the upper battery cell module of the two adjacent battery cell modules, and the second cooling plate covers the top of the lower battery cell module of the two adjacent battery cell modules; the mechanical strength of the first cooling plate is greater than that of the second cooling plate.

[0007] Optionally, the battery pack further comprises a connecting pipeline, the connecting pipeline comprises a water inlet pipeline and a water outlet pipeline, the first cooling plate and the second cooling plate each comprise a water inlet and a water outlet arranged in communication with the inside, the water inlet pipeline is communicated with the water inlet, and the water outlet pipeline is communicated with the water outlet.

[0008] Optionally, the water inlet pipeline and the water outlet pipeline each comprise a connection main pipe and a plurality of connection branch pipes, the connection branch pipes are arranged between the first cooling plate below any of the battery cell modules and the second cooling plate above the battery cell modules, the connection main pipe is communicated with the plurality of connection branch pipes, and the connection main pipe is provided with a water inlet main port or a water outlet main port.

[0009] Optionally, the middle portions of the plurality of connection branch pipes are connected in parallel to the same connection main pipe.

[0010] Optionally, the water inlet port and the water outlet port are each provided with a water nozzle connector, the connection branch pipe is fixedly connected to the water nozzle connector, and in any adjacent first cooling plate and second cooling plate, the water nozzle connector of the first cooling plate is arranged opposite to the water nozzle connector of the second cooling plate.

[0011] Optionally, the first cooling plate and the second cooling plate each comprise a protruding portion, the protruding portion protrudes from the first cooling plate or the second cooling plate in the second direction, and the water inlet port and the water outlet port are arranged on the protruding portion.

[0012] Optionally, a buffer gasket is arranged between the first cooling plate and the second cooling plate arranged in a stack.

[0013] Optionally, the ratio of the total thickness of the buffer gasket and the first cooling plate or the ratio of the total thickness of the buffer gasket and the second cooling plate is 0.05 to 0.5.

[0014] Optionally, in the vertical direction, the first cooling plate at the bottommost position comprises a mounting structure, and the mounting structure is in the same plane as the first cooling plate at the bottommost position.

[0015] Optionally, the mounting structure comprises a pressing edge of the edge of the first cooling plate at the bottommost position, so that the coverage area of the first cooling plate at the bottommost position is greater than the coverage area of the other first cooling plates or the coverage area of the second cooling plate.

[0016] Optionally, the thickness of the first cooling plate is greater than the thickness of the second cooling plate.

[0017] Optionally, the ratio of the thickness of the first cooling plate to the thickness of the second cooling plate is not greater than 5 / 2.

[0018] Optionally, the first cooling plate comprises an extrusion formed plate, and the second cooling plate comprises a punched plate.

[0019] Optionally, the cooling plate assembly is provided with at least three cooling plate assemblies in the vertical direction, the uppermost cooling plate assembly comprises the second cooling plate, and the lowermost cooling plate assembly comprises the first cooling plate; the cooling plate assemblies between the uppermost cooling plate assembly and the lowermost cooling plate assembly comprise the first cooling plate and the second cooling plate stacked from top to bottom.

[0020] Advantages:

[0021] The battery pack in the utility model is stacked by a plurality of battery cell modules, cooling plate assemblies are arranged between adjacent two battery cell modules, the mechanical strength of the first cooling plate in the cooling plate assembly is greater than that of the second cooling plate, the first cooling plate is arranged below the battery cell module and supports the battery cell module, supports the battery cell module while cooling the battery cell module, improves the mechanical strength of the battery pack, the second cooling plate is arranged above the battery cell module and only plays a cooling role, and the heat dissipation capacity of the battery pack is improved. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is the axonometric view of the battery pack provided by the embodiment of the utility model;

[0023] Figure 2 is the side view of the liquid cooling system provided by the embodiment of the utility model;

[0024] Figure 3 is the axonometric view of the liquid cooling system provided by the embodiment of the utility model;

[0025] Figure 4 is Figure 3 is the local enlarged view of A in the utility model;

[0026] Figure 5 is the liquid cooling flow channel schematic view of the second cooling plate or the first cooling plate provided by the embodiment of the utility model.

[0027] In the drawing:

[0028] 10, battery cell module; 11, battery box; 12, partition plate;

[0029] 100, connecting pipeline; 101, water inlet total port; 102, water outlet total port; 103, connecting main pipe; 104, connecting branch pipe; 110, water inlet pipeline; 120, water outlet pipeline;

[0030] 200, cooling plate assembly; 201, water inlet; 202, water outlet; 203, protrusion; 204, water nozzle joint; 205, liquid cooling flow channel; 210, first cooling plate; 212, mounting structure; 220, second cooling plate. DETAILED DESCRIPTION

[0031] The utility model will be described in further detail below in combination with the drawings and examples. It can be understood that the specific examples described herein are only used to explain the utility model and are not limited to the utility model. In addition, it should be noted that only the parts related to the utility model are shown in the drawings for ease of description, not all the structures.

[0032] In the description of the utility model, unless otherwise explicitly specified and limited, the terms "connected", "connected", "fixed" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship of two elements. For ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.

[0033] In the utility model, unless otherwise explicitly specified and limited, the "upper" or "lower" of the first feature to the second feature can include that the first and second features are in direct contact, or the first and second features are not in direct contact but are in contact through another feature between them. Moreover, the "upper", "upper" and "upper" of the first feature to the second feature include that the first feature is directly above and obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The "below", "below" and "below" of the first feature to the second feature include that the first feature is directly below and obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0034] In the description of the embodiment, the terms "upper", "lower", "right", etc. orientation or position relationship is based on the orientation or position relationship shown in the drawings, only for the convenience of description and simplification of operation, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore cannot be understood as a limitation on the utility model. In addition, the terms "first", "second" are only used to distinguish in description and have no special meaning.

[0035] The first direction described in the embodiment is Figure 2 and Figure 3 X direction in and vertical height direction and the stacking direction of the battery cell module 10; the second direction is Figure 2 and Figure 3The Y direction in the figure refers to the horizontal direction and the length direction of the cooling plate assembly 200.

[0036] like Figure 1 As shown, this embodiment first provides a battery pack, which specifically includes a battery housing 11 and a liquid cooling system. The liquid cooling system consists of several cooling plate assemblies 200. Adjacent cooling plate assemblies 200 form a space for accommodating the cell modules 10. Connecting pipes 100 connect the cooling plate assemblies 200. A partition 12 divides the battery housing 11 into two spaces, placing the cooling plate assemblies 200 and connecting pipes 100 in these two spaces respectively. The cooling plate assemblies 200 are fixed to the battery housing 11 by riveting or welding. Using the liquid cooling system in this embodiment, the battery pack can cool the multi-layer cell modules 10, improving the cooling effect on the middle portion of the multi-layer cell modules 10, and thus improving the reliability and service life of the multi-layer cell modules 10.

[0037] Specifically, the battery cell module 10 is composed of several individual battery cells stacked horizontally.

[0038] like Figures 2 to 4 As shown, specifically, the cooling plate assembly 200 includes a first cooling plate 210 and a second cooling plate 220. The first cooling plate 210 supports the bottom of the upper battery cell module 10 among two adjacent battery cell modules 10, and the second cooling plate 220 covers the top of the lower battery cell module 10 among two adjacent battery cell modules 10. The mechanical strength of the first cooling plate 210 is greater than that of the second cooling plate 220.

[0039] In this embodiment, the battery pack is composed of several stacked cell modules 10. A cooling plate assembly 200 is disposed between two adjacent cell modules 10. The first cooling plate 210 in the cooling plate assembly 200 has a greater mechanical strength than the second cooling plate 220. The first cooling plate 210 is positioned below the cell modules 10, providing both cooling and support, thus improving the mechanical strength of the battery pack. The second cooling plate 220 is positioned above the cell modules 10, serving only a cooling function, thereby improving the heat dissipation capacity of the battery pack. This battery pack achieves excellent cooling of the multi-layered cell modules 10, with superior cooling effect, and can achieve improved load-bearing capacity and mechanical strength of the battery pack at low cost, without compromising cooling performance.

[0040] It should be noted that the liquid cooling system specifically includes the connecting pipeline 100 and at least three cooling plate assemblies 200, wherein: along the first direction, the topmost cooling plate assembly 200 only includes the second cooling plate 220; along the first direction, the bottommost cooling plate assembly 200 includes the first cooling plate 210; and the cooling plate assemblies 200 between the topmost cooling plate assembly 200 and the bottommost cooling plate assembly 200 include the second cooling plate 220 and the first cooling plate 210 stacked from top to bottom. The liquid cooling system of the battery pack in this embodiment includes at least three cooling plate assemblies 200, and a containing space for containing the battery cell module 10 is formed between two adjacent cooling plate assemblies 200, that is, the liquid cooling system is used for liquid cooling and heat dissipation of the battery pack having at least two layers of battery cell modules 10, and one cooling plate assembly 200 is arranged at the upper end and the lower end of each layer of battery cell modules 10, which is used for heat dissipation of the battery cell module 10, and the heat dissipation effect is better. Moreover, the cooling plate assembly 200 is composed of the first cooling plate 210 and the second cooling plate 220, the topmost cooling plate assembly 200 is the second cooling plate 220, which has a lower cost and is only used for cooling the battery cell module 10; the bottommost cooling plate assembly 200 is the first cooling plate 210, which has a higher cost but better mechanical properties and a stronger pressure-bearing capacity; and the remaining liquid cooling assemblies in the middle are composed of the first cooling plate 210 above and the second cooling plate 220 below, which are stacked. The first cooling plate 210 is used for bearing the battery cell module 10, and the second cooling plate 220 is used for cooling the battery cell module 10 below. Therefore, the liquid cooling system can achieve good cooling of the multi-layer battery cell module 10, has a better cooling effect, and can low-costly improve the bearing capacity of the cooling system without affecting the cooling and heat dissipation effect.

[0041] Specifically, the first cooling plate 210 includes an extrusion molded plate, and the second cooling plate 220 includes a punched plate. Specifically, the first cooling plate 210 in this embodiment is extruded from an aluminum profile with a label of AL6061, which has a higher mechanical strength but a higher cost, and has a thickness of 6 mm to 10 mm, wherein the cavity height is 4 mm, and 2 mm of the aluminum plate above and below is not used as a cavity to provide support strength, so as to avoid that the battery cell module 10 presses the first cooling plate 210 to cause the surface of the first cooling plate 210 to be concave, and improve the flatness of the first cooling plate 210; and the second cooling plate 220 in this embodiment is punched from an aluminum profile with a label of AL3003mod, which has a lower cost and does not need to bear weight, so the mechanical strength is lower, and the thickness of the second cooling plate 220 ranges from 4 mm to 6 mm.

[0042] In the embodiment, the wall thickness of the first cooling plate 210 is greater than that of the second cooling plate 220, on the one hand due to the limitations of the extrusion and stamping process, and on the other hand, the greater wall thickness of the first cooling plate 210 can provide better support strength.

[0043] Specifically, the ratio of the thickness of the first cooling plate 210 to the thickness of the second cooling plate 220 is not greater than 5 / 2, which can ensure the cooling effect of the second cooling plate 220. If the second cooling plate 220 is too thin, there will not be enough internal space to open the flow channel. Specifically, in the embodiment, the thickness of the first cooling plate 210 is 8mm, and the thickness of the second cooling plate 220 is 6mm, and the ratio of the thickness of the first cooling plate 210 to the thickness of the second cooling plate 220 is 4 / 3. Details are not repeated here.

[0044] Optionally, the first cooling plate 210 and the second cooling plate 220 each include a water inlet 201 and a water outlet 202 in communication with the inside thereof, the connecting pipeline 100 is communicated with the water inlet 201 and the water outlet 202, and the connecting pipeline 100 includes a water inlet pipeline 110 and a water outlet pipeline 120. The water inlet pipeline 110 is communicated with the water inlet 201, and the water outlet pipeline 120 is communicated with the water outlet. The water inlet pipeline 110 is used for water inlet of the cooling plate assembly 200, and the water outlet pipeline 120 is used for water outlet of the cooling plate assembly 200, realizing the circulating flow of the cooling liquid in the cooling plate assembly 200, and the heat dissipation and cooling effect is better.

[0045] It should be noted that, along the first direction, the first cooling plate 210 located at the bottom includes a mounting structure 212, and the mounting structure 212 is in the same plane as the first cooling plate 210 located at the bottom. The mounting structure 212 is specifically a pressed edge of the edge of the first cooling plate 210 at the bottom, so that the coverage area of the first cooling plate 210 is greater than that of the other first cooling plate 210 or the second cooling plate 220, realizing the mounting of the first cooling plate 210 at the bottom and the battery box body 11.

[0046] As Figure 3 and Figure 4As shown, the water inlet pipeline 110 and the water outlet pipeline 120 each include a connection main pipe 103 and a plurality of connection branch pipes 104, the connection branch pipes 104 are arranged between any adjacent first cooling plate 210 and second cooling plate 220, the connection main pipe 103 is communicated with the plurality of connection branch pipes 104, and the connection main pipe 103 is provided with a water inlet main port 101 or a water outlet main port 102. By connecting the water outlet port 202 or the water inlet port 201 of the adjacent second cooling plate 220 and first cooling plate 210 through the connection branch pipe 104, and then connecting the connection branch pipe 104 through the connection main pipe 103, the parallel connection of the second cooling plate 220 and the first cooling plate 210 can be realized, the flow of each second cooling plate 220 and each first cooling plate 210 is more uniform, the heat dissipation and cooling capacity is improved, and the heat dissipation capacity of each second cooling plate 220 or each first cooling plate 210 is ensured to be the same, thereby ensuring the uniformity of heat dissipation.

[0047] Specifically, the middle portions of the plurality of connection branch pipes 104 are connected in parallel to the same connection main pipe 103, the pipeline is led out at the middle portion of the connection branch pipe 104 and communicated to the connection main pipe 103, the cooling medium in the single connection branch pipe 104 is uniformly distributed in the upward and downward directions while realizing the parallel connection of the plurality of connection branch pipes 104, the cooling effect of the first cooling plate 210 and the second cooling plate 220 is ensured to be consistent, and the cooling performance of the lithium-calcium battery pack is improved.

[0048] Optionally, the water inlet port 201 and the water outlet port 202 are each provided with a water nozzle connector 204, and the connection branch pipe 104 is fixedly connected to the water nozzle connector 204. The water nozzle connector 204 is made by machining, has low cost, and can reduce the use of quick plug connectors, thereby reducing the space occupied by the connectors and being beneficial to improving the energy density of the battery pack.

[0049] Further, in any adjacent first cooling plate 210 and second cooling plate 220, the water nozzle connector 204 of the first cooling plate 210 is arranged opposite to the water nozzle connector 204 of the second cooling plate 220. Through such arrangement, the length of the connection branch pipe 104 is reduced, the manufacturing cost of the connection pipeline 100 is reduced, and the volume of the liquid cooling system of the battery pack is reduced.

[0050] As Figure 4 and Figure 5As shown, in the embodiment, the first cooling plate 210 and the second cooling plate 220 each include a protruding portion 203, the protruding portion 203 protrudes from the first cooling plate 210 or the second cooling plate 220 in the second direction, and the water inlet 201 and the water outlet 202 are arranged on the protruding portion 203. The protruding portion 203 is arranged to enable the water inlet 201 and the water outlet 202 to protrude outward from the body portion of the first cooling plate 210 and the second cooling plate 220, so that the body portion is accommodated in one space of the battery box 11, and the water inlet 201 and the water outlet 202 are in another space, thereby achieving separation of the connecting pipeline 100 and the cooling plate assembly 200, and improving safety and reliability in use.

[0051] Specifically, as shown in FIG. 1, Figure 3 As shown, the protruding portion 203 where the water inlet 201 is located and the protruding portion 203 where the water outlet 202 is located can be divided into two protruding portions 203; as shown in FIG. 1, Figure 5 As shown, the protruding portion 203 where the water inlet 201 is located and the protruding portion 203 where the water outlet 202 is located can be integrally formed into one protruding portion 203, which is not limited in the embodiment.

[0052] Further, a buffer gasket is arranged between the first cooling plate 210 and the second cooling plate 220 arranged in a stack. The buffer gasket is used for buffering between the first cooling plate 210 and the second cooling plate 220 arranged in a stack, so as to avoid the second cooling plate 220 below being extruded and deformed, thereby improving the use reliability and service life of the cooling system of the battery pack.

[0053] It should be noted that the ratio of the total thickness of the buffer gasket and the first cooling plate 210, or the ratio of the total thickness of the buffer gasket and the second cooling plate 220 is 0.05 to 0.5. A gap with a predetermined thickness is left between the first cooling plate 210 and the second cooling plate 220 for mounting the buffer gasket, the thickness of the buffer gasket ranges from 2 mm to 3 mm, and the material of the buffer gasket is specifically foam. If the buffer gasket is too thin, it cannot achieve effective buffering between the upper and lower cell modules 10; if the buffer gasket is too thick, it will occupy the mounting space of the first cooling plate 210 and the second cooling plate 220, affecting the cooling effect. In the embodiment, the thickness of the first cooling plate 210 is 8 mm, the thickness of the second cooling plate 220 is 6 mm, and the thickness of the buffer gasket is 2 mm. The ratio of the total thickness of the buffer gasket and the first cooling plate 210 is 0.25, and the ratio of the total thickness of the buffer gasket and the second cooling plate 220 is 0.33.

[0054] As shown in FIG. 1, Figure 5 As shown in FIG. 1, Figure 5A schematic diagram of one of the liquid cooling channels 205 of the first cooling plate 210 and the second cooling plate 220 in the embodiment is given, the inner diameter of the connecting pipeline 100 connected by the liquid cooling channel 205 is 14mm, the height of the liquid cooling channel 205 is 4mm, and the height of the first cooling plate 210 is 8mm. The liquid cooling channel 205 includes a plurality of spiral-shaped inner flow channels to increase the heat exchange area of the liquid cooling channel 205 and the battery cell module 10 and improve the cooling capacity, which will not be described here.

[0055] The battery pack manufacturing method provided in the embodiment is used to manufacture the battery pack according to any one of the above-mentioned schemes, and includes the following steps: S1, preparing cooling plates: producing the first cooling plate 210 and the second cooling plate 220; S2, assembling to form a cooling plate assembly 200: placing one first cooling plate 210 at the bottom to form the bottom cooling plate assembly 200; placing one second cooling plate 220 at the top to form the top cooling plate assembly 200; stacking one first cooling plate 210 and one second cooling plate 220 from top to bottom to form a middle cooling plate assembly 200; S3, assembling and forming: spacing a plurality of middle cooling plate assemblies 200 between the top cooling plate assembly 200 and the bottom cooling plate assembly 200, and setting a predetermined distance between two adjacent cooling plate assemblies 200, and clamping the battery cell module 10 between the two adjacent cooling plate assemblies 200.

[0056] The battery pack manufactured by the battery pack manufacturing method can use the first cooling plate 210 to bear the battery cell module 10 and use the second cooling plate 220 to cool the battery cell module 10 below, so that the liquid cooling system of the battery pack can achieve good cooling of the multi-layer battery cell module 10, the cooling effect is better, and the functions of improving the bearing capacity and mechanical strength of the battery pack can be realized at low cost without affecting the cooling and heat dissipation effect.

[0057] Obviously, the above-mentioned embodiments of the utility model are only examples for clearly explaining the utility model, and are not a limitation on the embodiments of the utility model. For ordinary skilled persons in the art, various obvious changes, re-adjustments and replacements can be made without departing from the protection scope of the utility model. Here, it is not necessary and impossible to enumerate all the embodiments. Any modification, equivalent replacement and improvement made within the spirit and principle of the utility model should be included in the protection scope of the utility model claims.

Claims

1. A battery pack, characterized by, The battery pack comprises a cooling plate assembly (200) and a plurality of cell modules (10) stacked from top to bottom, and the cooling plate assembly (200) is arranged between any two adjacent cell modules (10). The cooling plate assembly (200) comprises a first cooling plate (210) and a second cooling plate (220), the first cooling plate (210) supports the bottom of the upper cell module (10) of the two adjacent cell modules (10), and the second cooling plate (220) covers the top of the lower cell module (10) of the two adjacent cell modules (10). The mechanical strength of the first cooling plate (210) is greater than that of the second cooling plate (220).

2. The battery pack of claim 1, wherein, The battery pack further comprises a connecting pipeline (100), the connecting pipeline (100) comprises a water inlet pipeline (110) and a water outlet pipeline (120), the first cooling plate (210) and the second cooling plate (220) each comprise a water inlet (201) and a water outlet (202) arranged in communication with the inside, the water inlet pipeline (110) is communicated with the water inlet (201), and the water outlet pipeline (120) is communicated with the water outlet.

3. The battery pack of claim 2, wherein, The water inlet pipeline (110) and the water outlet pipeline (120) each comprise a connecting main pipe (103) and a plurality of connecting branch pipes (104), the connecting branch pipe (104) is arranged between the first cooling plate (210) below any cell module (10) and the second cooling plate (220) above the cell module (10), the connecting main pipe (103) is communicated with a plurality of connecting branch pipes (104), and the connecting main pipe (103) is provided with a water inlet main port (101) or a water outlet main port (102).

4. The battery pack of claim 3, wherein, The middle part of the plurality of connecting branch pipes (104) is connected in parallel to the same connecting main pipe (103).

5. The battery pack of claim 3, wherein, The water inlet (201) and the water outlet (202) are each provided with a water nozzle connector (204), the connecting branch pipe (104) is fixedly connected to the water nozzle connector (204), and in any adjacent first cooling plate (210) and second cooling plate (220), the water nozzle connector (204) of the first cooling plate (210) is arranged opposite to the water nozzle connector (204) of the second cooling plate (220).

6. The battery pack of claim 3, wherein, The first cooling plate (210) and the second cooling plate (220) each comprise a protruding part (203), the protruding part (203) protrudes out of the first cooling plate (210) or the second cooling plate (220) along a second direction, and the water inlet (201) and the water outlet (202) are arranged on the protruding part (203).

7. The battery pack of any one of claims 1-6, wherein, The first cooling plate (210) and the second cooling plate (220) arranged in a stacked manner are clamped with a buffer gasket therebetween.

8. The battery pack of claim 7, wherein, The ratio of the total thickness of the buffer gasket and the first cooling plate (210), or the ratio of the total thickness of the buffer gasket and the second cooling plate (220) is 0.05 to 0.

5.

9. The battery pack of any one of claims 1-6, wherein, In the vertical direction, the first cooling plate (210) at the bottommost position comprises a mounting structure (212) which is in the same plane as the first cooling plate (210) at the bottommost position.

10. The battery pack of claim 9, wherein, The mounting structure (212) comprises a pressing edge of the edge of the first cooling plate (210) at the bottommost position, so that the coverage area of the first cooling plate (210) at the bottommost position is greater than the coverage area of the other first cooling plates (210) or the coverage area of the second cooling plate (220).

11. The battery pack of any one of claims 1-6, wherein, The wall thickness of the first cooling plate (210) is greater than the wall thickness of the second cooling plate (220).

12. The battery pack of claim 11, wherein, The ratio of the thickness of the first cooling plate (210) to the thickness of the second cooling plate (220) is not greater than 5 / 2.

13. The battery pack of any one of claims 1-6, wherein, The first cooling plate (210) comprises an extruded plate, and the second cooling plate (220) comprises a punched plate.

14. The battery pack of any one of claims 1-6, wherein, The cooling plate assembly (200) is provided with at least 3, in the vertical direction, the cooling plate assembly (200) at the topmost position comprises the second cooling plate (220), the cooling plate assembly (200) at the bottommost position comprises the first cooling plate (210); the cooling plate assembly (200) between the cooling plate assembly (200) at the topmost position and the cooling plate assembly (200) at the bottommost position comprises the first cooling plate (210) and the second cooling plate (220) stacked from top to bottom.

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