Battery pack

Abstract

The invention discloses a battery pack. The battery pack comprises a box shell, a plurality of battery assemblies and a plurality of water cooling plates, the box shell is provided with a cavity. The battery assembly is arranged in the cavity and comprises a plurality of single battery cells, and the single battery cells are arranged in sequence. Each water cooling plate is respectively arranged between two adjacent battery cell monomers in the battery assembly, and the two sides of each water cooling plate along the thickness direction are respectively attached to the two adjacent battery cell monomers. The water cooling plate of the battery pack is attached to the side faces of the battery cell single bodies, each battery cell single body is a cuboid and comprises two side faces and a thickness end face connected to the two side faces, the area of the two side faces of each battery cell single body is larger than that of the thickness end face, and the water cooling plate is arranged between the two battery cell single bodies, that is, the water cooling plate is attached to the large faces of the battery cell single bodies. Therefore, the heat exchange area of the water cooling plate and the battery cell monomers is greatly increased, and the cooling effect on the battery cell monomers is greatly improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular, to a battery pack. Background Art

[0002] With the rapid development of the new energy industry, the safety performance of batteries is becoming more and more important. The cooling effect of the battery cell inside the battery pack is a very important indicator of safety. The existing battery pack includes a box shell, a battery module and a cooling plate. The cooling plate and the battery module are arranged in the box shell. The battery module is arranged on the surface of the cooling plate and is in direct or indirect contact with the cooling plate. The cooling plate cools the battery module. The internal battery cell of the battery module is in contact with the water-cooled plate only at the bottom end face. The battery cell is usually a vertically placed rectangular structure. The bottom end face of the battery cell is the thickness end plate, which is the smaller surface among the several thickness end faces of the battery cell. This arrangement makes the contact area between the battery cell and the water-cooled plate smaller, and the cooling effect of the water-cooled plate on the battery cell is limited, which affects the service life of the entire battery pack. Summary of the invention

[0003] In order to solve one of the above-mentioned technical defects, a battery pack is provided in an embodiment of the present application.

[0004] This application adopts the following technical solutions:

[0005] A battery pack, comprising:

[0006] A box shell, wherein the box shell has a cavity;

[0007] A plurality of battery assemblies, wherein the battery assemblies are arranged in the cavity, and the battery assemblies include a plurality of battery cells, and the battery cells are arranged in sequence;

[0008] A plurality of water cooling plates, each of which is disposed between two adjacent battery cells in the battery assembly, and both sides of the water cooling plate along the thickness direction are respectively attached to the two adjacent battery cells.

[0009] Optionally, the water cooling plate includes a flexible body and a water inlet and a water outlet disposed on the flexible body, the flexible body has a water cooling channel, and the water cooling channel connects the water inlet and the water outlet, respectively.

[0010] Optionally, two sides of the flexible body along the thickness direction are respectively bonded to two adjacent battery cell monomers through colloid.

[0011] Optionally, a water cooling pipe is included, the water cooling pipe is located in the cavity, the water cooling pipe is extended along the arrangement direction of each battery cell of the battery assembly, and the water cooling pipe is respectively connected to each cooling plate.

[0012] Optionally, the water cooling plate package has a water inlet and a water outlet;

[0013] The water cooling pipeline includes a water inlet pipe and a water return pipe. The water inlet pipe is respectively connected to the water inlet nozzle of each cooling plate, and the water return pipe is respectively connected to the water outlet nozzle of each cooling plate.

[0014] Optionally, a pressure relief valve is provided on the top of the battery cell;

[0015] The water inlet pipe and the water return pipe extend through the top of each battery cell of the battery assembly;

[0016] When the temperature of the water cooling pipe reaches a set value, it can melt, so that the liquid in the water cooling pipe is injected into the cavity.

[0017] Optionally, a plurality of water inlet branches are arranged on the water inlet pipe, each of the water inlet branches is arranged in sequence along the extension direction of the water inlet pipe, and each of the water inlet branches is connected to a corresponding water inlet nozzle respectively;

[0018] The water return pipe has a plurality of water return branches, each of which is arranged in sequence along the extending direction of the water return pipe, and each of which is connected to a corresponding water outlet.

[0019] Optionally, the water inlet and the water outlet are arranged on both sides of the water cooling plate, and in the same water cooling pipe, each water return branch and each water inlet branch extend to both sides of the battery assembly along the width direction respectively to connect the corresponding water outlet and water inlet respectively;

[0020] The water inlet pipe and the water return pipe of the same water cooling pipeline are connected and located at the top of each battery cell.

[0021] Optionally, the water cooling pipe includes a plurality of support bars, each of which is located between the water inlet pipe and the water return pipe, and each of which is arranged in sequence at intervals along the extension direction of the water cooling pipe, and both ends of the support bar are respectively connected to the water inlet pipe and the water return pipe.

[0022] Optionally, comprising a manifold;

[0023] The busbar is located in the cavity and covers the battery assembly;

[0024] The water inlet pipe, the water return pipe and the support bar of the water cooling pipeline are located on the side of the busbar away from the battery assembly.

[0025] By adopting the above technical solution, the present application has the following beneficial effects:

[0026] The water cooling plate of the battery pack of the present application is bonded to the side of the battery cell. The battery cell is a rectangular parallelepiped, including two side surfaces and a thickness end surface connected to the two side surfaces. The area of ​​the two side surfaces of the battery cell is larger than the thickness end surface. The water cooling plate is arranged between the two battery cells, that is, the water cooling plate is bonded to the large surface of the battery cell. This greatly increases the heat exchange area between the water cooling plate and the battery cell, and thus also greatly improves the cooling effect on the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings are part of this application and are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention, but do not constitute an improper limitation of the present invention. Obviously, the drawings described below are only some embodiments. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0028] Figure 1 A schematic diagram of the structure of a battery pack provided by an embodiment of the present disclosure is shown;

[0029] Figure 2 A schematic diagram of the top view of the battery pack provided by an embodiment of the present disclosure is shown;

[0030] Figure 3 A schematic diagram showing the structure of the busbar and battery cells of the battery pack provided by the embodiment of the present disclosure;

[0031] Figure 4 A schematic diagram showing the structure of the cooperation between the water cooling pipe and the battery assembly of the battery pack provided by the embodiment of the present disclosure is shown;

[0032] Figure 5 A schematic diagram showing the structure of the cooperation between the water cooling pipe and the water cooling plate of the battery pack provided by the embodiment of the present disclosure is shown;

[0033] Figure 6 An enlarged structural schematic diagram of a water cooling plate of a battery pack provided in an embodiment of the present disclosure is shown;

[0034] Figure 7 A schematic diagram of the structure of the water cooling plate and battery cells of the battery pack provided in an embodiment of the present disclosure is shown.

[0035] In the figure: box shell 1, cavity 11, water cooling pipe 2, water inlet pipe 21, water inlet branch pipe 22, return pipe 23, water inlet branch pipe 24, support bar 25, water cooling plate 3, water inlet nozzle 31, water outlet nozzle 32, flexible body 33, pressure relief valve 4, avoidance port 5, busbar 6, aluminum bar 7, battery assembly 8, battery cell 81, battery assembly width direction X.

[0036] It should be noted that these drawings and textual descriptions are not intended to limit the conceptual scope of the present invention in any way, but are intended to illustrate the concept of the present invention for those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The following embodiments are used to illustrate the present invention but are not used to limit the scope of the present invention.

[0038] In the description of the present invention, it should be noted that the terms "upper", "lower", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0039] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0040] See also Figures 1 to 7 As shown, an embodiment of the present application provides a battery pack, including a box shell, a plurality of battery assemblies and a plurality of water-cooling plates. The box shell 1 has a cavity. The battery assembly is arranged in the cavity, and the battery assembly includes a plurality of battery cells, and each of the battery cells is arranged in sequence. Each of the water-cooling plates 3 is respectively arranged between two adjacent battery cells in the battery assembly, and the two sides of the water-cooling plate 3 along the thickness direction are respectively attached to the two adjacent battery cells. The water-cooling plate 3 of the battery pack of the present application is attached to the side of the battery cell (the two side surfaces of the battery cell along the thickness direction). Because the battery cell is a rectangular parallelepiped, including two side surfaces and thickness end surfaces connected to the two side surfaces, the area of ​​the two side surfaces of the battery cell is larger than the thickness end surface, and the water-cooling plate 3 is arranged between the two battery cells, that is, the water-cooling plate 3 is attached to the large surface of the battery cell. This greatly increases the heat exchange area between the water-cooling plate 3 and the battery cell, and thus greatly improves the cooling effect on the battery cell. Furthermore, the battery cell located in the middle of the battery pack has two end faces on both sides along the thickness direction that are attached to the water cooling plate 3, and heat is exchanged on both sides of the battery cell simultaneously, further improving the cooling efficiency of the battery cell. Each battery assembly can be a row of battery cells, and each of the battery cells is arranged in sequence. Every two or more battery assemblies constitute a battery module.

[0041] In some possible implementation schemes, the water-cooling plate 3 includes a flexible body and a water inlet nozzle 31 and a water outlet nozzle 32 arranged on the flexible body, and the flexible body has a water cooling channel, and the water cooling channel connects the water inlet nozzle 31 and the water outlet nozzle 32 respectively. The battery pack may be bumpy during transportation or use, and collision or friction may occur between two adjacent battery cells due to the bumps. The water-cooling plate 3 of the flexible body is arranged between two adjacent battery cells, which can play a buffering role and prevent the two adjacent battery cells from colliding with each other or rubbing against each other and causing damage. Furthermore, a water inlet nozzle 31 and a water outlet nozzle 32 are provided at one end of each water-cooling plate 3 away from the bottom end face of the battery cell, so as to facilitate communication with the water inlet pipe 21 and the return pipe 23 of the water cooling pipe 2. The water-cooling plate can be made of elastic material.

[0042] In some possible implementations, the two sides of the flexible body along the thickness direction are respectively bonded to two adjacent battery cells by colloid. The water cooling plate 3 is bonded to the battery cell, which plays a role in positioning the water cooling plate 3 so that the water cooling plate 3 will not change position due to bumps, and the water cooling plate 3 can always remain in contact with the large surface of the battery cell.

[0043] Furthermore, the water-cooling plate 3 is bonded to the large surface of the battery cell monomer by means of a heat-conducting structural adhesive. The heat-conducting structural adhesive does not affect the heat exchange efficiency and ensures that the water-cooling plate 3 is firmly bonded.

[0044] In some possible implementations, the battery pack includes a water cooling pipe 2, the water cooling pipe 2 is located in the cavity, the water cooling pipe 2 is extended along the arrangement direction of each battery cell of the battery assembly, and the water cooling pipe 2 is respectively connected to each cooling plate. The water cooling pipe 2 can be partially arranged inside the box shell 1, so as to facilitate connection with each water cooling plate 3 inside the box shell 1. The coolant enters each water cooling plate 3 in turn through the water cooling pipe 2, and each pair of battery cells is cooled by the water cooling plate 3.

[0045] In some possible implementation schemes, the water-cooled plate 3 includes a water inlet 31 and a water outlet 32. The water-cooled pipe 2 includes a water inlet pipe 21 and a water return pipe 23, wherein the water inlet pipe 21 is respectively connected to the water inlet 31 of each cooling plate, and the water return pipe 23 is respectively connected to the water outlet 32 ​​of each cooling plate. The water inlet 31 and the water outlet 32 ​​are respectively connected to the water inlet pipe 21 and the water return pipe 23, and the coolant flows into the water-cooled plate 3 through the water inlet 31. After the heat exchange of the coolant is completed, it flows out from the water outlet 32 ​​of the water-cooled plate 3 to the water return pipe 23, realizing heat exchange of the battery cell monomer and performing effective heat dissipation.

[0046] Furthermore, the water inlet 31 and the water outlet 32 ​​of the water cooling plate 3 are both provided with quick plugs, and the water inlet pipe 21 and the water return pipe of the water cooling pipe 2 are both provided with quick sockets, and the quick plugs can be directly plugged into the quick sockets. The quick plug structure is used for connection, and no professional tools are required, making the installation process more time-saving and labor-saving.

[0047] In some possible implementation schemes, a pressure relief valve 4 is provided on the top of the battery cell. The water inlet pipe 21 and the water return pipe 23 extend through the top of each battery cell of the battery assembly. When the temperature of the water cooling pipe 2 reaches the set value, it can melt, so that the liquid in the water cooling pipe 2 is injected into the cavity. When a battery cell undergoes thermal runaway, high temperature will be generated inside the battery cell, and the high-temperature solution or gas will be discharged from the pressure relief valve 4 on the top of the battery cell. The high-temperature solution or gas is sprayed on the water cooling pipe 2 located on the top of the pressure relief valve 4, and the water cooling pipe 2 melts due to the high temperature. The coolant in the water cooling pipe 2 is sprayed on the battery cell to cool the battery cell.

[0048] Furthermore, the water cooling pipe 2 can be made of a material that is not resistant to high temperatures, such as PVC, TPE, etc. When thermal runaway occurs in the battery cell and the temperature of the sprayed solution or gas is higher than the melting point of the water cooling pipe 2 material, the water cooling pipe 2 will melt and the liquid in the water cooling pipe will be directly injected into the battery pack.

[0049] In some possible implementation schemes, the water inlet pipe 21 is provided with a plurality of water inlet branches 22, each of which is sequentially arranged along the extension direction of the water inlet pipe 21, and each of which is respectively connected to a corresponding water inlet nozzle 31. The water return pipe 23 has a plurality of water return branches 24, each of which is sequentially arranged along the extension direction of the water return pipe 23, and each of which is respectively connected to a corresponding water outlet nozzle 32. Such a connection structure plays a certain role in stabilizing the water inlet pipe 21 and the water return pipe 23, and can ensure that each of the water inlet branches 22 and the water return branch 24 is always fixed on the top of the battery cell.

[0050] Furthermore, quick-plugs are provided on the ends of the water inlet branch pipe 22 and the water return branch pipe 24 away from the water inlet pipe 21 and the water return pipe 23. The quick plugs on the water inlet nozzle 31 and the water outlet nozzle 32 of the water cooling plate 3 can be directly plugged into the quick plugs of the water inlet branch pipe 22 and the water return branch pipe 24, and the connection is made through the quick plug structure, which is convenient and fast, improves the installation efficiency, and is conducive to daily maintenance.

[0051] In some possible implementation schemes, the water inlet nozzle 31 and the water outlet nozzle 32 are respectively arranged on both sides of the water cooling plate 3. In the same water cooling pipe 2, each water return branch 24 and each water inlet branch 22 extend to both sides of the battery assembly along the width direction respectively to connect the corresponding water outlet nozzle 32 and water inlet nozzle 31 respectively. The water inlet pipe 21 and the water return pipe 23 of the same water cooling pipe 2 are connected and located at the top of each battery cell. The water inlet pipe 21 and the water return pipe 23 are connected to form an integrated structure. Each water inlet branch 22 and the water return branch 24 are respectively located on both sides of the integrated structure. The direction of the force applied by each water inlet branch 22 to the integrated structure is opposite to the direction of the force applied by the water return branch 24 to the integrated structure, so that the integrated structure is stably fixed to the top of each battery cell, the position is fixed, and it will not be easily displaced. The connection structure between the water cooling plate 3 and the water cooling pipe 2 is stable, ensuring that the water inlet pipe 21 and the water return pipe 23 will not be far away from the pressure relief valve 4. The structural design of the water cooling pipe 2 of the present application makes the pipe neat and clear without any tangling, and is more convenient for connection with the water inlet 31 and the water outlet 32. Figure 2 As shown, the direction of the arrow X in the figure is the width direction of the battery cell, and the direction of the arrow X is also the width direction of the battery assembly.

[0052] In some possible implementation schemes, the water cooling pipe 2 includes a plurality of support bars 25, each of which is located between the water inlet pipe 21 and the water return pipe 23, and each of which is arranged at intervals in the extension direction of the water cooling pipe 2, and the two ends of the support bars 25 are respectively connected to the water inlet pipe 21 and the water return pipe 23. The support bars 25 can connect the water inlet pipe 21 and the water return pipe 23 to form an integrated structure, so that the directions of the forces applied to the integrated structure by the water return branch pipe 24 and each water inlet branch pipe 22 are roughly opposite (the combined force of the water return branch pipe 24 and each water inlet branch pipe 22 can be directed toward the upper end surface of the battery cell monomer, and the combined force is relatively small), the water return branch pipe 24 and the water inlet branch pipe 22 can effectively play the role of fixing the integrated structure, ensuring that the water inlet pipe 21 and the water return pipe 23 are always at the top of the battery cell monomer, and the support bars 25 are arranged in this way so that the water inlet pipe 21 and the water return pipe 23 do not need to be fixed separately, which simplifies the structure and minimizes the changes to the battery assembly structure.

[0053] In some possible implementations, the battery pack includes a busbar 6, which is located in the cavity and covers the battery assembly. The water inlet pipe 21, the return pipe 23 and the support bar 25 of the water cooling pipe 2 are located on the side of the busbar 6 away from the battery assembly. The busbar 6 plays a role in supporting the water cooling pipe 2. The busbar 6 is provided with a avoidance port 5 at each pressure relief valve 4 of the battery cell monomer. The water inlet pipe 21 and the return pipe 23 of the water cooling pipe 2 extend along the arrangement direction of each avoidance port 5 on the busbar 6. The water inlet pipe 21 and the return pipe 23 are respectively located on both sides of the avoidance port 5. Each support bar 25 is located between the water inlet pipe 21 and the return pipe 23, and at least part of the support bar is located at the top of the avoidance port 5. The busbar 6 includes an aluminum bar sheet 7, and the pole ears of each battery cell of the battery assembly are electrically connected through multiple aluminum bar sheets 7. Each battery assembly is provided with a corresponding water cooling pipe 2, and the water inlet pipe 21, the water return pipe 23 and the support bar 25 of the water cooling pipe 2 are arranged on the top of the busbar 6. When the battery cell has thermal runaway, the high-temperature solution or gas is ejected from the escape port 5, the water inlet pipe 21 and the water return pipe 23 of the water cooling pipe 2 will melt at high temperature, and the liquid inside the water cooling pipe 2 will be injected into the battery pack, and the liquid can be sprayed onto the battery cell as fire water to achieve the effect of cooling down.

[0054] The above is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this patent can make some changes or modify the technical contents suggested above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the solution of the present invention.

Claims

1. A battery pack, characterized in that: include: A box shell, wherein the box shell has a cavity; A plurality of battery assemblies, wherein the battery assemblies are arranged in the cavity, and the battery assemblies include a plurality of battery cells, and the battery cells are arranged in sequence; A plurality of water cooling plates, each of which is disposed between two adjacent battery cells in the battery assembly, and both sides of the water cooling plate along the thickness direction are respectively attached to the two adjacent battery cells.

2. The battery pack according to claim 1, characterized in that: The water cooling plate comprises a flexible body and a water inlet and a water outlet arranged on the flexible body, the flexible body has a water cooling channel, and the water cooling channel connects the water inlet and the water outlet respectively.

3. The battery pack according to claim 2, characterized in that: The two sides of the flexible body along the thickness direction are respectively bonded to two adjacent battery core monomers through colloid.

4. The battery pack according to claim 1, characterized in that: It comprises a water cooling pipe, which is located in the cavity, and is extended along the arrangement direction of each battery cell of the battery assembly, and is respectively connected to each cooling plate.

5. The battery pack according to claim 4, characterized in that: The water cooling plate package has a water inlet and a water outlet; The water cooling pipeline includes a water inlet pipe and a water return pipe. The water inlet pipe is respectively connected to the water inlet nozzle of each cooling plate, and the water return pipe is respectively connected to the water outlet nozzle of each cooling plate.

6. The battery pack according to claim 5, characterized in that: A pressure relief valve is provided on the top of the battery cell; The water inlet pipe and the water return pipe extend through the top of each battery cell of the battery assembly; When the temperature of the water cooling pipe reaches a set value, it can melt, so that the liquid in the water cooling pipe is injected into the cavity.

7. The battery pack according to claim 6, characterized in that: A plurality of water inlet branches are arranged on the water inlet pipe, each of which is arranged in sequence along the extension direction of the water inlet pipe, and each of which is connected to a corresponding water inlet nozzle; The water return pipe has a plurality of water return branches, each of which is arranged in sequence along the extending direction of the water return pipe, and each of which is connected to a corresponding water outlet.

8. The battery pack according to claim 7, characterized in that: The water inlet and the water outlet are respectively arranged on both sides of the water cooling plate. In the same water cooling pipe, each water return branch and each water inlet branch extend to both sides of the battery assembly along the width direction to respectively connect with the corresponding water outlet and water inlet; The water inlet pipe and the water return pipe of the same water cooling pipeline are connected and located at the top of each battery cell.

9. The battery pack according to claim 8, characterized in that: The water cooling pipe includes a plurality of support bars, each of which is located between the water inlet pipe and the water return pipe, and each of which is arranged in sequence and spaced apart along the extension direction of the water cooling pipe, and both ends of the support bar are respectively connected to the water inlet pipe and the water return pipe.

10. The battery pack according to claim 9, characterized in that: Including manifolds; The busbar is located in the cavity and covers the battery assembly; The water inlet pipe, the water return pipe and the support bar of the water cooling pipeline are located on the side of the busbar away from the battery assembly.

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