Battery pack

Abstract

The invention provides a battery pack. The battery pack comprises a box body, a liquid cooling plate and a pump, and a battery module and immersion liquid for immersing the battery module are arranged in the box body; the liquid cooling plate comprises a liquid cooling main body arranged in the box body and a liquid inlet pipe nozzle and a liquid outlet pipe nozzle which are communicated with the liquid cooling main body, the liquid cooling main body is in contact with the immersion liquid, the liquid inlet pipe nozzle and the liquid outlet pipe nozzle are communicated with the outside of the box body, and the pump is arranged in the box body and used for exchanging the immersion liquid at the top of the box body and the immersion liquid at the bottom of the box body. The immersion liquid in the box body does not exchange with the outside, so that the requirements on the mechanical strength and the structural air tightness of the box body can be reduced, the processing cost of the box body can be reduced, the exchange of the immersion liquid at the top and the immersion liquid at the bottom in the box body can be realized by the pump, and the temperature equalization effect is achieved; the liquid inlet pipe nozzle and the liquid outlet pipe nozzle of the liquid cooling plate pass through the outside of the box body, and cooling liquid flowing circularly can be introduced into the liquid cooling plate, so that the heat exchange efficiency is 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] In the related art, immersed battery packs can be divided into immersed battery packs with circulating immersion liquid and immersed battery packs with stationary immersion liquid.

[0003] For submerged battery packs with circulating immersion fluid, the fluid can continuously flow into the battery pack at a constant temperature, achieving a significant cooling effect. However, the circulation of the immersion fluid places high demands on the battery pack's mechanical strength and structural airtightness, leading to high production costs. For submerged battery packs with stationary immersion fluid, the mechanical strength and structural airtightness requirements are lower, and processing is less challenging. However, submerged battery packs do not exchange heat with the outside world and cannot meet the heat dissipation requirements of the battery pack during high-power charging and discharging. Summary of the Invention

[0004] An embodiment of the present application provides a battery pack that can improve the circulation flow of the immersion liquid. However, the mechanical strength and structural airtightness of the battery pack are very high, and the production cost is high. In addition, the immersion battery pack does not exchange heat with the outside world and cannot meet the heat dissipation requirements of the battery pack when charging and discharging at high power.

[0005] An embodiment of the present application provides a battery pack, comprising:

[0006] A box body, wherein a battery module and an immersion liquid for immersing the battery module are arranged in the box body;

[0007] a liquid cooling plate, comprising a liquid cooling body disposed within the housing, and a liquid inlet nozzle and a liquid outlet nozzle in communication with the liquid cooling body, the liquid cooling body being in contact with the immersion liquid, the liquid inlet nozzle and the liquid outlet nozzle in communication with the exterior of the housing;

[0008] A pump is provided in the box body, and the pump is used to exchange the immersion liquid at the top of the box body with the immersion liquid at the bottom of the box body.

[0009] In some embodiments, the box body includes a first chamber and a second chamber, the battery module is arranged in the first chamber, the liquid cooling plate is arranged in the second chamber, the bottom wall of the first chamber is arranged between the battery module and the liquid cooling body, the side wall of the first chamber is arranged between the battery module and the side wall of the box body, and the first chamber is connected to the second chamber.

[0010] In some embodiments, a plurality of heat exchange holes are provided on the bottom wall of the first chamber, and the bottom wall of the first chamber is opposite to and spaced from the liquid cooling body.

[0011] In some embodiments, the pump is disposed between a side wall of the first chamber and a side wall of the tank.

[0012] In some embodiments, the pump is configured to transfer the immersion liquid in the first chamber into the second chamber.

[0013] In some embodiments, the pump is detachably connected to a side wall of the first chamber.

[0014] In some embodiments, one end of the side wall of the first chamber close to the top wall of the box body is connected to the top wall of the box body, and the pump includes an inlet pipe and a liquid outlet pipe, the liquid inlet opening of the liquid inlet pipe is passed through the side wall of the first chamber, the distance between the liquid inlet opening of the liquid inlet pipe and the top wall of the box body is smaller than the distance between the liquid inlet opening and the bottom wall of the box body, and the distance between the liquid outlet opening of the liquid outlet pipe and the top wall of the box body is larger than the distance between the liquid outlet opening and the bottom wall of the box body.

[0015] In some embodiments, the liquid inlet opening faces the bottom wall of the box body, and the liquid outlet opening faces the bottom wall of the box body.

[0016] In some embodiments, a chamfer is provided at a connection between the side wall of the box body and the bottom wall of the box body.

[0017] In some embodiments, an opening of the first chamber close to one end of the top wall of the box body is larger than an opening of the first chamber away from one end of the top wall of the box body.

[0018] In some embodiments, the liquid cooling body is disposed between the battery module and the bottom wall of the box body, and a plurality of grooves are disposed on a surface of the liquid cooling body on one side close to the battery module.

[0019] In some embodiments, the battery module includes a plurality of battery cells, a structural member is provided between two adjacent battery cells, and the structural member extends along the height direction of the box body.

[0020] In some embodiments, the battery cell includes a first side wall and a second side wall that are adjacent to each other, an area of ​​the first side wall is greater than an area of ​​the second side wall, and the structural member is in contact with the first side wall.

[0021] In some embodiments, two of the structural members are disposed between two adjacent battery cells, and the two structural members are spaced apart.

[0022] Beneficial effects of the embodiments of the present application:

[0023] In the embodiments of the present application, by preventing the immersion liquid in the box from being exchanged with the outside world, the requirements for the mechanical strength and structural airtightness of the box can be reduced, and the processing cost of the box can be reduced. The pump can realize the exchange of the immersion liquid at the top and the immersion liquid at the bottom of the box to achieve a uniform temperature effect; the liquid inlet nozzle and the liquid outlet nozzle of the liquid cooling plate pass through the outside of the box, and the circulating coolant can be introduced into the liquid cooling plate, thereby improving the heat exchange efficiency and improving the technical problem that the submerged battery pack does not exchange heat with the outside world and cannot meet the heat dissipation requirements of the battery pack under high power charging and discharging. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 is a three-dimensional schematic diagram of a battery pack provided in an embodiment of the present application;

[0026] Figure 2 yes Figure 1 Disassembly diagram of the battery pack;

[0027] Figure 3 yes Figure 1 A cross-sectional view of the battery pack at section AA;

[0028] Figure 4 This is a force simulation diagram of the cover of an immersed battery pack with circulating immersion liquid in the related art;

[0029] Figure 5 is a schematic diagram of a circulation path of a battery pack provided in an embodiment of the present application;

[0030] Figure 6 yes Figure 1 A schematic diagram of an enlarged structure of grooves on the surface of the liquid-cooled body;

[0031] Figure 7 yes Figure 2 A partial disassembly diagram of the battery module.

[0032] Description of reference numerals:

[0033] The housing 10, the top wall 10a of the housing 10, the side walls 10b of the housing 10, the bottom wall 10c of the housing 10, the chamfer 101, the first chamber 11a, the heat exchange holes 11b, the second chamber 12a, the first flow channel 121a, and the second flow channel 121b;

[0034] Battery module 20, battery cell 21, first side wall 211, second side wall 212, structural member 22, end plate 23, bus bar 24;

[0035] Liquid cooling plate 30, liquid cooling body 31, groove 31a, fin 311, liquid inlet nozzle 321, liquid outlet nozzle 322;

[0036] Pump 40, liquid inlet pipe 41, liquid inlet opening 41a, liquid outlet pipe 42, liquid outlet opening 42a;

[0037] The distance h1 between the liquid inlet opening 41a of the liquid inlet pipe 41 and the top wall 10a of the box body 10, the distance h2 between the liquid inlet opening 41a and the bottom wall 10c of the box body 10, the distance h3 between the liquid outlet opening 42a of the liquid outlet pipe 42 and the top wall 10a of the box body 10, and the distance h4 between the liquid outlet opening 42a and the bottom wall 10c of the box body 10;

[0038] The height direction D1 of the housing 10 . DETAILED DESCRIPTION

[0039] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present application. In addition, it should be understood that the specific implementation methods described herein are only used to illustrate and explain the present application, and are not used to limit the present application. In the present application, unless otherwise specified, the directional words used, such as "upper" and "lower", generally refer to the upper and lower parts of the device in actual use or working state, specifically the drawing direction in the accompanying drawings; and "inside" and "outside" refer to the outline of the device.

[0040] The embodiment of the present application provides a battery pack, such as Figures 1 to 3 As shown, the battery pack includes a case 10, a liquid cooling plate 30 and a pump 40. The case 10 is provided with a battery module 20 and an immersion liquid for immersing the battery module 20. The liquid cooling plate 30 includes a liquid cooling body 31 arranged in the case 10 and a liquid inlet nozzle 321 and a liquid outlet nozzle 322 connected to the liquid cooling body 31. The liquid cooling body 31 is in contact with the immersion liquid, and the liquid inlet nozzle 321 and the liquid outlet nozzle 322 are connected to the outside of the case 10. The pump 40 is arranged in the case 10 and is used to exchange the immersion liquid at the top of the case 10 with the immersion liquid at the bottom of the case 10.

[0041] like Figure 2 and Figure 3As shown, the box body 10 includes a top wall 10a and a bottom wall 10c opposite to each other and a side wall 10b disposed between the top wall 10a and the bottom wall 10c. The side wall 10b is connected to the edge of the top wall 10a and the edge of the bottom wall 10c to form a sealed accommodating space.

[0042] like Figure 1 and Figure 2 As shown, the battery module 20 is disposed in the accommodation space of the box body 10. The battery module 20 includes a plurality of stacked battery cells 21.

[0043] The battery module 20 is immersed in an immersion liquid, where immersion refers to contact between the immersion liquid and the battery module 20. The immersion liquid may include fluorinated liquids, hydrofluoroethers, silicone oils, and hydrocarbon compounds. The immersion liquid provides both cooling and insulation. The battery module 20 generates heat during operation, and the immersion liquid's contact with the battery module 20 helps cool the module and prevent excessive temperature rise.

[0044] like Figure 2 and Figure 3 As shown, the liquid cooling plate 30 includes a liquid cooling body 31, a liquid inlet nozzle 321 and a liquid outlet nozzle 322. The liquid cooling body 31 is disposed in the accommodation space of the box body 10, and the liquid outlet nozzle 322 is disposed through the side wall 10b of the box body 10.

[0045] The liquid inlet nozzle 321, the liquid cooling body 31, and the liquid outlet nozzle 322 form a channel for the flow of coolant. Coolant can flow from the liquid inlet nozzle 321 into the liquid cooling body 31 and then out of the liquid outlet nozzle 322. The liquid cooling plate 30 can exchange heat with the outside world through the coolant, conducting heat from the interior of the housing 10 out of the housing 10 via the coolant, thereby lowering the temperature inside the housing 10 and improving the heat exchange efficiency of the battery pack, making the battery pack suitable for the heat dissipation requirements of high-power charging and discharging.

[0046] Alternatively, as Figure 2 As shown, the liquid inlet nozzle 321 and the liquid outlet nozzle 322 are arranged on the same side of the box body 10, so that the liquid inlet nozzle 321 and the liquid outlet nozzle 322 are more convenient to operate when connected to the external pipeline. The external pipeline can be used to provide circulating coolant for the liquid cooling plate 30.

[0047] In some embodiments, the liquid inlet nozzle 321 and the liquid outlet nozzle 322 may also be disposed on different sides of the box body 10 .

[0048] At least one pump 40 is provided within the housing 10. The pump 40 is used to transfer the immersion liquid at the top of the housing 10 to the bottom of the housing 10, or to transfer the immersion liquid at the bottom of the housing 10 to the top of the housing 10. The top of the housing 10 refers to the side close to the top wall 10a, and the bottom of the housing 10 refers to the side close to the bottom wall 10c. Within the housing 10, the immersion liquid with a higher temperature rises, and thus the temperature of the immersion liquid at the top of the housing 10 is higher than the temperature of the immersion liquid at the bottom of the housing 10. By exchanging the immersion liquid at the top and bottom of the housing 10 through the pump 40, the circulation of the immersion liquid within the housing 10 can be achieved, thereby achieving a uniform temperature of the immersion liquid within the housing 10.

[0049] like Figure 4 As shown, Figure 4 This is a force simulation diagram of the box cover of an immersion battery pack with circulating immersion liquid in the related art. Different pressure levels are distinguished by different colors in the simulation diagram. In the color bar chart on the left, the pressure value decreases from top to bottom. That is to say, the upper color represents a larger pressure value, and the lower color represents a smaller pressure value. Among them, the pressure in the red area is the largest, and the pressure in the blue area is relatively small. Among them, the pressure in the middle area of ​​the box cover is greater than the pressure in the edge area of ​​the box cover. That is to say, in the immersion battery pack with circulating immersion liquid, the force on the box cover is uneven. In order to prevent the box cover from being deformed or damaged under pressure, it is necessary to make the box cover able to withstand the pressure in the middle area (that is, the pressure value in the red area), which puts higher requirements on the mechanical strength of the box cover, resulting in increased processing difficulty and increased processing cost.

[0050] In the present application, the pump 40 is disposed within the housing 10, and the immersion liquid circulates within the housing 10 without needing to circulate with the outside world. Compared to battery packs with circulating immersion liquid, the stress on the housing 10 is more uniform, the mechanical strength requirements for the housing 10 are lower, and the processing difficulty of the housing 10 is relatively low. Therefore, the battery pack of the present application can reduce the processing difficulty of the battery pack housing 10 while meeting the heat dissipation requirements of the battery pack under high-power charging and discharging.

[0051] When the cell 21 in the battery module 20 opens its valve, the substance ejected from the cell 21 will contaminate the immersion liquid. Since the immersion liquid in the box 10 is not exchanged with the outside world, it will not affect the immersion liquid of other parallel battery packs, reducing safety hazards.

[0052] In some embodiments, as Figure 3As shown, the box body 10 includes a first chamber 11a and a second chamber 12a, the battery module 20 is arranged in the first chamber 11a, the liquid cooling plate 30 is arranged in the second chamber 12a, the bottom wall of the first chamber 11a is arranged between the battery module 20 and the liquid cooling body 31, the side wall of the first chamber 11a is arranged between the battery module 20 and the side wall 10b of the box body 10, and the first chamber 11a is connected to the second chamber 12a.

[0053] like Figure 2 and Figure 3 As shown, the first chamber 11a and the second chamber 12a can be separated by a partition disposed within the housing 10. The partition can serve as the bottom wall of the first chamber 11a, the side wall of the first chamber 11a, the top wall of the first chamber 11a, etc. The shape of the first chamber 11a can be set as needed and is not limited in this application. The side wall of the first chamber 11a is connected to the bottom wall of the first chamber 11a.

[0054] It should be noted that when the shape of the first chamber 11 a matches the shape of the box body 10 , the structure inside the box body 10 can be made more compact, thereby improving the energy density of the battery pack.

[0055] Optionally, the bottom wall of the first chamber 11a is disposed between the battery module 20 and the liquid-cooling body 31. The battery module 20 can be disposed on the bottom wall of the first chamber 11a, that is, the bottom wall of the first chamber 11a can be used to support the battery module 20. The side wall of the first chamber 11a is disposed between the battery module 20 and the side wall 10b of the box body 10.

[0056] Optionally, to further improve the energy density of the battery pack, the shape of the sidewall of the first chamber 11a matches the shape of the sidewall 10b of the box body 10. That is, the surface of the sidewall of the first chamber 11a can be substantially evenly spaced from the surface of the sidewall 10b of the box body 10.

[0057] Alternatively, as Figure 2 As shown, in order to further improve the energy density of the battery pack, part of the sidewall of the first chamber 11a can be shared with part of the sidewall of the box body 10. For example, when the box body 10 includes four sidewalls, the first chamber 11a can include only two opposite sidewalls, and the other two sidewalls of the first chamber 11a are shared with the sidewall 10b of the box body 10.

[0058] The first chamber 11 a and the second chamber 12 a are in communication with each other, which means that a through hole is provided on the side wall or the bottom wall of the first chamber 11 a , and the immersion liquids of the two chambers are in communication with each other at the through hole.

[0059] In some embodiments, as Figure 2 As shown, a plurality of heat exchange holes 11 b are provided on the bottom wall of the first chamber 11 a , and the bottom wall of the first chamber 11 a is opposite to the liquid cooling body 31 and spaced apart from each other.

[0060] The bottom wall of the first chamber 11a can be opposite to and spaced apart from the liquid-cooled body 31. Here, the relative arrangement means that the surface of the bottom wall of the first chamber 11a is roughly aligned with the upper surface of the liquid-cooled plate 30. The spaced arrangement means that a gap is provided between the bottom wall of the first chamber 11a and the upper surface of the liquid-cooled body 31. A first flow channel 121a is formed between the bottom wall of the first chamber 11a and the upper surface of the liquid-cooled body 31. The immersion liquid in the first flow channel 121a is in contact with the liquid-cooled body 31, which facilitates heat exchange with the liquid-cooled body 31. The heat of the immersion liquid can be discharged to the outside of the box 10 via the coolant in the liquid-cooled body 31.

[0061] like Figure 2 As shown, the bottom wall of the first chamber 11a is provided with a plurality of heat exchange holes 11b, and the heat exchange holes 11b are distributed on the bottom wall of the first chamber 11a. Since the battery module 20 is provided in the first chamber 11a, the heat generated by the battery module 20 during operation will increase the temperature of the immersion liquid. Therefore, the temperature of the immersion liquid in the first chamber 11a will be higher than the temperature of the immersion liquid in the second chamber 12a near the liquid cooling plate 30. By providing the heat exchange holes 11b on the bottom wall of the first chamber 11a, the heat of the immersion liquid in the first chamber 11a can be exchanged with the immersion liquid in the second chamber 12a through the heat exchange holes 11b, thereby further reducing the temperature of the immersion liquid in the first chamber 11a. The liquid cooling plate 30 is provided in the second chamber 12a, and the coolant in the liquid cooling plate 30 can reduce the temperature of the immersion liquid near the liquid cooling plate 30, thereby achieving cooling of the battery pack.

[0062] In some embodiments, the pump 40 is disposed between the sidewall of the first chamber 11a and the sidewall 10b of the housing 10. This arrangement isolates the pump 40 from the immersion liquid in the first chamber 11a, preventing the pump 40 from directly contacting the overheated immersion liquid in the first chamber 11a and thus shortening the life of the pump 40.

[0063] In some embodiments, a pump 40 is used to transfer the immersion liquid in the first chamber 11 a to the second chamber 12 a .

[0064] like Figure 2As shown, because the immersion liquid in the first chamber 11a is in contact with the battery module 20, the temperature of the immersion liquid in the first chamber 11a rises faster, while the immersion liquid in the second chamber 12a is farther away from the battery module 20, and the temperature of the immersion liquid in the second chamber 12a rises more slowly. By providing a pump 40, the pump 40 can realize the circulation exchange of the immersion liquid in the first chamber 11a and the immersion liquid in the second chamber 12a, so that the heat in the first chamber 11a can be transferred to the second chamber 12a, slowing down the temperature rise of the immersion liquid in the first chamber 11a. The immersion liquid in the second chamber 12a is in contact with the liquid cooling body 31, and the liquid cooling body 31 can transfer the heat in the second chamber 12a to the outside of the housing 10, thereby reducing the temperature rise of the immersion liquid in the second chamber 12a. Through the above arrangement, the temperature rise of the battery module 20 can be further reduced.

[0065] In some embodiments, the pump 40 is detachably connected to the sidewall of the first chamber 11a. For example, the pump 40 can be fixed to the sidewall of the first chamber 11a using bolts or the like. This arrangement prevents the pump 40 from swaying within the housing 10 and deviating from its original position, thereby preventing the immersion liquid at the top and bottom of the housing 10 from being exchanged.

[0066] Specifically, if Figure 2 and Figure 3 As shown, one end of the side wall of the first chamber 11a close to the top wall 10a of the box body 10 is connected to the top wall 10a of the box body 10, and the pump 40 includes a liquid inlet pipe 41 and a liquid outlet pipe 42. The liquid inlet opening 41a of the liquid inlet pipe 41 is arranged on the side wall of the first chamber 11a. The distance h1 between the liquid inlet opening 41a of the liquid inlet pipe 41 and the top wall 10a of the box body 10 is smaller than the distance h2 between the liquid inlet opening 41a and the bottom wall 10c of the box body 10. The distance h3 between the liquid outlet opening 42a of the liquid outlet pipe 42 and the top wall 10a of the box body 10 is larger than the distance h4 between the liquid outlet opening 42a and the bottom wall 10c of the box body 10.

[0067] Since hot immersion liquid rises, the temperature of the immersion liquid in the first chamber 11a near the top wall 10a of the box body 10 is higher. By arranging the liquid inlet opening 41a near the top wall 10a of the box body 10, the immersion liquid with a higher temperature can be transported to the bottom wall 10c of the box body 10, thereby improving the heat exchange effect.

[0068] Alternatively, as Figure 3 As shown, in order to further improve the energy density of the battery pack, the side wall of the first chamber 11a can be flush with the surface of the side wall 10b of the box body 10 close to the top wall 10a of the box body 10, and the upper end of the side wall of the first chamber 11a is flush with the upper end of the side wall 10b of the box body 10. The volume of the first chamber 11a can be increased through the above arrangement.

[0069] The volume of the immersion liquid in the first chamber 11a can be smaller than the volume of the housing 10, that is, the liquid surface of the immersion liquid is spaced apart from the top wall 10a of the housing 10. This arrangement can reduce the mechanical impact of the flow of the immersion liquid on the top wall 10a of the housing 10 when the pump 40 is operating.

[0070] like Figure 3 As shown, the pump 40 includes an inlet pipe 41 and an outlet pipe 42. The pump 40 transfers the immersion liquid flowing from the inlet opening 41a of the inlet pipe 41 to the outlet opening 42a of the outlet pipe 42. The inlet opening 41a is the end of the inlet pipe 41, and the outlet opening 42a is the end of the outlet pipe 42.

[0071] The distance h1 between the liquid inlet opening 41a of the liquid inlet pipe 41 and the top wall 10a of the case 10 is smaller than the distance h2 between the liquid inlet opening 41a and the bottom wall 10c of the case 10. This means that the liquid inlet opening 41a is located close to the top wall 10a of the case 10. The distance h3 between the liquid outlet opening 42a of the liquid outlet pipe 42 and the top wall 10a of the case 10 is larger than the distance h4 between the liquid outlet opening 42a and the bottom wall 10c of the case 10. This means that the liquid outlet opening 42a is located close to the bottom wall 10c of the case 10.

[0072] like Figure 5 As shown, Figure 5 This is a schematic diagram of the circulation path of the battery pack provided in an embodiment of the present application. The arrows in the figure indicate the flow direction of the fluid. The fill pattern in the figure shows the immersion liquid. In the first chamber 11a, the immersion liquid near the bottom wall of the first chamber 11a can exchange heat with the liquid-cooled body 31 through the heat exchange hole 11b, and the immersion liquid near the bottom wall of the first chamber 11a heats up slowly; while the immersion liquid near the top wall of the first chamber 11a cannot exchange heat with the liquid-cooled body 31. Therefore, the immersion liquid near the top wall of the first chamber 11a heats up quickly. The immersion liquid near the top wall of the first chamber 11a is transported to the side of the second chamber 12a near the bottom wall 10c of the box body 10 by the pump 40, so that heat exchange between the immersion liquid in the first chamber 11a and the immersion liquid near the liquid-cooled body 31 in the second chamber 12a can be achieved. The immersion liquid in the second chamber 12a near the liquid-cooling body 31 exchanges heat with the liquid-cooling body 31 and then enters the first chamber 11a through the heat exchange hole 11b to cool the battery module 20. It is then transported by the pump 40 to the side of the second chamber 12a near the bottom wall 10c of the box body 10 for the next cycle.

[0073] Pump 40 enables internal circulation of the immersion liquid within the battery pack, while the liquid cooling plate 30 enables external circulation of the coolant. This combination of internal and external circulation further improves heat exchange efficiency and meets the heat dissipation requirements of the battery pack during high-power charging and discharging.

[0074] Further, combined with Figure 2 and Figure 3 A second flow channel 121b is formed between the side wall of the first chamber 11a and the side wall 10b of the housing 10. The liquid inlet nozzle 321 and the liquid outlet nozzle 322 are arranged on the side wall shared by the first chamber 11a and the housing 10, that is, the second flow channel 121b and the liquid inlet nozzle 321 and the liquid outlet nozzle 322 are arranged on different sides of the housing 10. Through the above arrangement, the first flow channel 121a area can be cooled by the liquid cooling plate 30, and the second flow channel 121b area can be evenly heated by the pump 40. The first flow channel 121a is located at the bottom of the housing 10, and the second flow channel 121b is located on the side of the housing 10. The first flow channel 121a and the second flow channel 121b are connected, so that the multiple areas inside the housing 10 can achieve a uniform temperature effect.

[0075] The number of pumps 40 may be at least one. For example, the number of pumps 40 is two, and the two pumps 40 are respectively provided for the two second flow channels 121b. By providing multiple pumps 40, the heat exchange efficiency can be improved.

[0076] It should be noted that if Figure 5 As shown, in the present application, a pump 40 is used for circulation cooling, and the circulation path of the immersion liquid is carried out around the side wall of the first chamber 11a. There is no battery cell 21 blocking the circulation path. The circulation path of the immersion liquid is shorter, the flow resistance is smaller, and the heat exchange effect is better.

[0077] In some embodiments, the liquid inlet opening 41 a faces the bottom wall 10 c of the box body 10 , and the liquid outlet opening 42 a faces the bottom wall 10 c of the box body 10 .

[0078] like Figure 3 and Figure 5 As shown, the liquid inlet opening 41a faces the bottom wall 10c of the housing 10. Immersion liquid at the liquid inlet opening 41a can flow into the liquid inlet opening 41a along the bottom wall 10c of the housing 10 toward the top wall 10a of the housing 10. The liquid outlet opening 42a faces the bottom wall 10c of the housing 10. Immersion liquid flowing out of the liquid outlet opening 42a can flow into the first flow channel 121a under the suction of the pump 40. Under the suction of the pump 40, the immersion liquid in the first flow channel 121a enters the liquid inlet opening 41a along the bottom wall 10c of the housing 10 toward the top wall 10a of the housing 10, thereby achieving circulation of the immersion liquid within the housing 10. By setting the orientations of the liquid outlet opening 42a and the liquid inlet opening 41a, the flow resistance of the immersion liquid can be reduced.

[0079] In some embodiments, as Figure 3 As shown, the connection between the side wall 10b and the bottom wall 10c of the box body 10 is provided with a chamfer 101. Chamfering 101 refers to the process of creating an angled surface on the material. Chamfering 101 includes rounding and beveling. The rounded surface is arc-shaped, while the beveled surface is straight.

[0080] like Figure 3 As shown, chamfer 101 is a chamfered angle, and the surface of chamfer 101 forms an obtuse angle with the side wall 10b of the box body 10, and the surface of chamfer 101 forms an obtuse angle with the bottom wall 10c of the box body 10. By providing chamfer 101, the flow resistance at the connection between the side wall 10b of the box body 10 and the bottom wall 10c of the box body 10 can be reduced, which is more conducive to the circulation of the immersion liquid.

[0081] In some embodiments, the opening of the first chamber 11a near the top wall 10a of the box 10 is larger than the opening of the first chamber 11a at the end away from the top wall 10a of the box 10. The battery module 20 is placed in the box as a whole, and the lifting equipment is clamped on the top wall and edges of the battery module 20. To avoid interference between the side walls 10b of the box 10 and the lifting equipment, the opening of the first chamber 11a near the top wall 10a of the box 10 is set to be larger. The opening of the first chamber 11a at the end away from the top wall 10a of the box 10 is set to be smaller, which can reduce the amount of immersion fluid used and improve the energy density of the battery pack.

[0082] In some embodiments, as Figure 3 and Figure 6 As shown, the liquid cooling body 31 is disposed between the battery module 20 and the bottom wall 10c of the housing 10. Multiple grooves 31a are provided on the surface of the liquid cooling body 31, which is located near the battery module 20. The multiple grooves 31a on the surface of the liquid cooling body 31 increase the contact area between the liquid cooling plate 30 and the immersion liquid, improving heat exchange efficiency.

[0083] Alternatively, as Figure 6 As shown, the surface of the liquid cooling plate 30 may be provided with fins 311, and grooves 31a are formed between two adjacent fins 311. The shape of the fins 311 can be set as needed, and this application does not impose any restrictions on this. For example, the fins 311 can extend in a straight line, a broken line, or a curved line. When the fins 311 extend in a straight line, they can be straight fins. When the fins 311 extend along a broken line, they can be serrated fins. When the fins 311 extend along a curved line, they can be wavy fins. The fins 311 can also be of other shapes, as long as the grooves 31a are formed between two adjacent fins 311 to increase the heat exchange area between the liquid cooling body 31 and the immersion liquid. Figure 6 Straight fins are shown, but this should not be construed as limiting the present application.

[0084] In some embodiments, as Figure 2 and Figure 7 As shown, the battery module 20 includes a plurality of battery cells 21 , and a structural member 22 is provided between two adjacent battery cells 21 . The structural member 22 extends along the height direction D1 of the box body 10 .

[0085] The structural member 22 can be made of an elastic material, such as foam. By placing the structural member 22 between the battery cells 21, it can absorb dimensional tolerances of the battery cells 21. When the battery module 20 is assembled into the first chamber 11a, the structural member 22 can be compressed to match the size of the first chamber 11a, reducing the machining precision requirements for the first chamber 11a.

[0086] Alternatively, as Figure 2 As shown, the battery module 20 further includes end plates 23 , which are disposed at both ends of the battery module 20 . The end plates 23 can protect the battery cells 21 and prevent the battery cells 21 from being damaged by external collisions.

[0087] A busbar 24 is further provided on the side of the battery cell 21 facing away from the bottom wall 10 c of the box body 10 . The busbar 24 is used to connect the multiple battery cells 21 in series and in parallel.

[0088] In some embodiments, as Figure 7 As shown, the battery cell 21 includes a first side wall 211 and a second side wall 212 adjacent to each other. The area of ​​the first side wall 211 is larger than that of the second side wall 212 , and the structural member 22 is in contact with the first side wall 211 .

[0089] The battery cell 21 can be a square battery cell 21. The sidewalls of the battery cell 21 include a first sidewall 211 and a second sidewall 212 that are adjacent and connected. The area of ​​the first sidewall 211 is larger than the area of ​​the second sidewall 212. In other words, the first sidewall 211 is the large end surface of the battery cell 21, and the second sidewall 212 is the small end surface of the battery cell 21. The structural member 22 is disposed between the large end surfaces of two adjacent battery cells 21.

[0090] In some embodiments, two structural members 22 are disposed between two adjacent battery cells 21 , and the two structural members 22 are spaced apart.

[0091] There may be two structural members 22, each in the form of an elongated plate. The long sides of the structural members 22 may extend along the height of the battery cells 21. The height of the battery cells 21 is the same as the height D1 of the housing 10. The structural member 22 has two opposing surfaces along the thickness direction, each of which contacts an adjacent first sidewall 211, thereby separating the two adjacent battery cells 21.

[0092] The long sides of the two structural members 22 that are close to each other are spaced apart to form a flow channel along the height direction D1 of the box body 10. Figure 5 and Figure 7When the pump 40 transports the immersion liquid near the top wall 10a of the box body 10 to the side near the bottom wall 10c of the box body 10, the immersion liquid in the first flow channel 121a can flow into the first chamber 11a through the heat exchange hole 11b, and flow along the flow channel formed between the two adjacent structural members 22 toward the side of the top wall 10a of the box body 10, and enter the liquid inlet opening 41a, thereby realizing the circulation of the immersion liquid.

[0093] The above is a detailed introduction to the embodiments of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of ​​the present application. At the same time, for those skilled in the art, based on the ideas of the present application, there may be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A battery pack, characterized in that: include: A box (10), wherein a battery module (20) and an immersion liquid for immersing the battery module (20) are arranged in the box (10); A liquid cooling plate (30) includes a liquid cooling body (31) disposed in the housing (10) and a liquid inlet nozzle (321) and a liquid outlet nozzle (322) in communication with the liquid cooling body (31), wherein the liquid cooling body (31) contacts the immersion liquid, and the liquid inlet nozzle (321) and the liquid outlet nozzle (322) are in communication with the outside of the housing (10); A pump (40) is provided in the box (10), and the pump (40) is used to exchange the immersion liquid at the top of the box (10) and the immersion liquid at the bottom of the box (10).

2. The battery pack according to claim 1, wherein: The box (10) includes a first chamber (11a) and a second chamber (12a); the battery module (20) is arranged in the first chamber (11a); the liquid cooling plate (30) is arranged in the second chamber (12a); the bottom wall of the first chamber (11a) is arranged between the battery module (20) and the liquid cooling body (31); the side wall of the first chamber (11a) is arranged between the battery module (20) and the side wall (10b) of the box (10); and the first chamber (11a) is communicated with the second chamber (12a).

3. The battery pack according to claim 2, wherein: The bottom wall of the first chamber (11a) is provided with a plurality of heat exchange holes (11b), and the bottom wall of the first chamber (11a) is opposite to the liquid cooling body (31) and is spaced apart from each other.

4. The battery pack according to claim 3, wherein: The pump (40) is disposed between a side wall of the first chamber (11a) and a side wall (10b) of the box (10).

5. The battery pack according to claim 4, characterized in that: The pump (40) is used to transport the immersion liquid in the first chamber (11a) to the second chamber (12a).

6. The battery pack according to claim 4, characterized in that: The pump (40) is detachably connected to the side wall of the first chamber (11a).

7. The battery pack according to claim 4, characterized in that: One end of the side wall of the first chamber (11a) close to the top wall (10a) of the box body (10) is connected to the top wall (10a) of the box body (10); the pump (40) comprises a liquid inlet pipe (41) and a liquid outlet pipe (42); the liquid inlet opening (41a) of the liquid inlet pipe (41) is provided through the side wall of the first chamber (11a); the distance (h1) between the liquid inlet opening (41a) of the liquid inlet pipe (41) and the top wall (10a) of the box body (10) is smaller than the distance (h2) between the liquid inlet opening (41a) and the bottom wall (10c) of the box body (10); and the distance (h3) between the liquid outlet opening (42a) of the liquid outlet pipe (42) and the top wall (10a) of the box body (10) is larger than the distance (h4) between the liquid outlet opening (42a) and the bottom wall (10c) of the box body (10).

8. The battery pack according to claim 7, characterized in that: The liquid inlet opening (41a) faces the bottom wall (10c) of the box body (10), and the liquid outlet opening (42a) faces the bottom wall (10c) of the box body (10).

9. The battery pack according to claim 2, wherein: A chamfer (101) is provided at the connection between the side wall (10b) of the box body (10) and the bottom wall (10c) of the box body (10).

10. The battery pack according to claim 2, wherein: The opening of the first chamber (11a) at one end close to the top wall (10a) of the box body (10) is larger than the opening of the first chamber (11a) at one end away from the top wall (10a) of the box body (10).

11. The battery pack according to any one of claims 1 to 10, characterized in that: The liquid cooling body (31) is arranged between the battery module (20) and the bottom wall (10c) of the box body (10), and a plurality of grooves (31a) are provided on a surface of one side of the liquid cooling body (31) close to the battery module (20).

12. The battery pack according to any one of claims 1 to 10, characterized in that: The battery module (20) includes a plurality of battery cells (21), a structural member (22) is provided between two adjacent battery cells (21), and the structural member (22) extends along a height direction (D1) of the box body (10).

13. The battery pack according to claim 12, wherein: The battery core (21) comprises a first side wall (211) and a second side wall (212) adjacent to each other, the area of ​​the first side wall (211) is larger than the area of ​​the second side wall (212), and the structural member (22) is in contact with the first side wall (211).

14. The battery pack according to claim 13, wherein: Two of the structural members (22) are arranged between two adjacent battery cells (21), and the two structural members (22) are arranged at intervals.

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