Battery cell, battery pack and energy storage system

Abstract

The invention provides a battery cell, a battery pack and an energy storage system. The battery cell comprises a shell, a core package, a positive electrode pin, a positive electrode heat conduction insulating layer, a negative electrode pin and a negative electrode heat conduction insulating layer. The shell comprises a plurality of side plates which define a containing cavity, and the core bag is located in the containing cavity. And a positive pole and a negative pole are arranged on a side plate of the shell. The core package is provided with a positive tab and a negative tab. And the positive tab and the negative tab respectively face the two side plates without the post terminals. The anode pin is electrically connected with the anode lug and the anode column, and the anode heat conduction insulating layer is located between the anode pin and the shell and transmits heat of the anode lug to the shell. The negative electrode pin is electrically connected with the negative electrode lug and the negative electrode column, and the negative electrode heat conduction insulating layer is located between the negative electrode pin and the shell and transmits heat of the negative electrode lug to the shell. Therefore, the pins can realize electric connection between the tabs and the pole columns, and the heat-conducting insulating layer can transfer heat of the core package to the shell, so that the heat dissipation efficiency of the core package is improved, uniform-temperature heat dissipation of the battery cells is realized, the heat dissipation efficiency of the battery pack is improved, and the service life of the battery pack is prolonged.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery, in particular to a battery cell, a battery pack and an energy storage system. BACKGROUND

[0002] Lithium battery has the characteristics of high energy density and long cycle life, and is widely used in energy storage, electric vehicles and standby power fields. The battery pack of lithium battery will generate a large amount of heat in the process of charging and discharging. Overheating will accelerate the side reaction of the battery cell inside the battery pack, reduce the performance and service life of the battery. Therefore, the inside of the battery pack is usually provided with a heat dissipation system to cool the battery cell of the battery pack.

[0003] The current heat dissipation methods mainly include air cooling and liquid cooling. Among them, liquid cooling becomes the mainstream design due to its high heat transfer rate and low failure rate. For square battery pack, bottom cooling method is usually used, which mainly exchanges heat at the bottom of the battery cell. However, the internal heat of the battery cell is mainly concentrated at the top of the tab, and the cooling effect of the bottom cooling method on the upper half of the battery cell is poor, resulting in a large temperature difference between the upper and lower parts of the battery cell, which causes poor heat uniformity inside the battery cell. SUMMARY

[0004] The present application provides a battery cell, a battery pack and an energy storage system to improve the heat dissipation efficiency inside the battery cell, realize uniform temperature cooling of the battery cell, and improve the heat dissipation efficiency and service life of the battery pack.

[0005] In a first aspect, the present application provides an electric core. The electric core comprises a shell, a core package, a positive electrode lead, a positive electrode heat-conductive insulation layer, a negative electrode lead and a negative electrode heat-conductive insulation layer. Specifically, the shell comprises a plurality of side plates, which enclose a receiving cavity, and the core package is located in the receiving cavity. The shell is provided with a positive electrode column and a negative electrode column, and any one of the positive electrode column and the negative electrode column is located on any one of the plurality of side plates. The core package has a positive electrode tab and a negative electrode tab, the positive electrode tab faces one of the plurality of side plates which is not provided with the any one of the positive electrode column and the negative electrode column, and the negative electrode tab faces another one of the plurality of side plates which is not provided with the any one of the positive electrode column and the negative electrode column. The positive electrode lead is electrically connected to the positive electrode tab and the positive electrode column, the positive electrode heat-conductive insulation layer is arranged on a side of the positive electrode lead away from the positive electrode tab, and the positive electrode heat-conductive insulation layer is in contact with the one side plate. The negative electrode lead is electrically connected to the negative electrode tab and the negative electrode column, the negative electrode heat-conductive insulation layer is arranged on a side of the negative electrode lead away from the negative electrode tab, and the negative electrode heat-conductive insulation layer is in contact with the another side plate. In the electric core of the present application, the positive electrode lead is electrically connected to the positive electrode tab and the positive electrode column, the positive electrode heat-conductive insulation layer can transfer the heat of the positive electrode tab to the shell, the negative electrode lead is electrically connected to the negative electrode tab and the negative electrode column, and the negative electrode heat-conductive insulation layer can transfer the heat of the negative electrode tab to the shell, thereby realizing the transfer of the heat of the core package to the shell, improving the heat dissipation efficiency of the core package, realizing the uniform heat dissipation of the electric core, and thereby improving the heat dissipation efficiency and service life of the battery pack.

[0006] In a possible implementation, the area of the positive electrode heat-conductive insulation layer is greater than or equal to the area of the part of the positive electrode lead located between the positive electrode heat-conductive insulation layer and the positive electrode tab. Similarly, the area of the negative electrode heat-conductive insulation layer is greater than or equal to the area of the part of the negative electrode lead located between the negative electrode heat-conductive insulation layer and the negative electrode tab. In this way, on the one hand, the heat transfer area between the positive electrode lead and the positive electrode tab, and the heat transfer area between the negative electrode lead and the negative electrode tab can be increased, thereby improving the heat dissipation efficiency of the core package; on the other hand, the positive electrode heat-conductive insulation layer can insulate and isolate the positive electrode lead from the shell, and the negative electrode heat-conductive insulation layer can insulate and isolate the negative electrode lead from the shell, thereby avoiding the conduction between the core package and the shell.

[0007] When the position of the core package relative to the shell is specifically set, the positive electrode tab does not face the positive electrode column, and the negative electrode tab does not face the negative electrode column. Therefore, the positive electrode lead and the negative electrode lead need to be arranged in a bent shape. In a possible implementation, the positive electrode lead is L-shaped, one end of the positive electrode lead is located between the positive electrode heat-conductive insulation layer and the positive electrode tab, and the other end of the positive electrode lead is located between the positive electrode column and the core package. The positive electrode heat-conductive insulation layer is located between the one side plate and the one end of the positive electrode lead. Similarly, the negative electrode lead is L-shaped, one end of the negative electrode lead is located between the negative electrode heat-conductive insulation layer and the negative electrode tab, and the other end of the negative electrode lead is located between the negative electrode column and the core package. The negative electrode heat-conductive insulation layer is located between the another side plate and the one end of the negative electrode lead.

[0008] In a possible implementation, the positive heat-conductive insulating layer can cover the one side plate, and the negative heat-conductive insulating layer can cover the other side plate, so as to achieve large-area heat transfer between the shell and the heat-conductive insulating layer, and improve the heat dissipation efficiency of the core package.

[0009] In the above battery cell, the core package can include two surfaces. The two surfaces can be oppositely arranged, or can be adjacently arranged. In a possible implementation, the tab of the core package can be a full-tab structure, large-area welding of the pin and the tab can be achieved, the transmission distance of the current can be reduced, and the uniformity of the power transmission performance in the core package can be improved. Specifically, the positive tab is arranged on one of the two surfaces, and the positive tab is bent towards and covers the one surface. The negative tab is arranged on the other of the two surfaces, and the negative tab is bent towards and covers the other surface. Alternatively, in another implementation, the tab of the core package can be a multi-tab structure. Specifically, the positive tab can include a plurality of positive tab pieces, and the plurality of positive tab pieces are respectively electrically connected with the positive pins. The negative tab can include a plurality of negative tab pieces, and the plurality of negative tab pieces are respectively electrically connected with the negative pins.

[0010] In a possible implementation, the one side plate away from the positive heat-conductive insulating layer is provided with a first heat dissipation plate, and / or the other side plate away from the negative heat-conductive insulating layer is provided with a second heat dissipation plate. The first heat dissipation plate and the second heat dissipation plate are used for heat transfer with the liquid cooling plate in the battery package, so as to transfer the heat of the shell to the liquid cooling plate and achieve heat dissipation.

[0011] In the present application, the material used to make the heat dissipation plate is not limited. For example, the first heat dissipation plate can include a metal heat dissipation plate or a metal matrix composite heat dissipation plate, and the second heat dissipation plate can include a metal heat dissipation plate or a metal matrix composite heat dissipation plate. Specifically, the heat dissipation plate can be a metal heat dissipation plate, such as an aluminum heat dissipation plate or a copper heat dissipation plate. Alternatively, the heat dissipation plate can be a metal matrix composite heat dissipation plate. The metal matrix composite heat dissipation plate uses a metal with high thermal conductivity as a matrix, and uses inorganic non-metallic fibers, whiskers, particles or nanoparticles as reinforcing bodies. The matrix and the reinforcing bodies are compounded and made into a metal matrix composite heat dissipation plate. The matrix can include copper matrix, magnesium matrix or aluminum matrix, etc.

[0012] The positive heat-conductive insulating layer can include at least one of an epoxy resin heat-conductive insulating layer, a silicone rubber heat-conductive insulating layer, a silicone grease heat-conductive insulating layer and an insulating ceramic heat-conductive insulating layer, and the negative heat-conductive insulating layer includes at least one of an epoxy resin heat-conductive insulating layer, a silicone rubber heat-conductive insulating layer, a silicone grease heat-conductive insulating layer and an insulating ceramic heat-conductive insulating layer, which are not specifically limited here.

[0013] In a second aspect, the application also provides a battery pack. The battery pack specifically comprises a shell and at least one battery cell of the first aspect. The battery cell is located in the shell. In the battery pack, the pin can realize the electrical connection between the tab and the pole, and the heat-conducting insulating layer can realize the heat transfer between the core package and the shell, so that the heat of the core package in the battery cell is transferred to the shell through the pin and the heat-conducting insulating layer, and is dissipated through the shell, thereby realizing the uniform heat dissipation of the battery cell and improving the heat dissipation efficiency and service life of the battery pack.

[0014] In a possible implementation, a liquid cooling plate is arranged in the shell. Among the plurality of side plates of the shell, at least one side plate which is not arranged with any pole is in contact with the liquid cooling plate. Therefore, the battery cell is mounted on the liquid cooling plate, so that the heat of the battery cell can be dissipated through the liquid cooling plate.

[0015] When the shell of the battery cell is arranged with the first heat dissipation plate and the second heat dissipation plate, the heat inside the battery cell is transferred to the shell of the battery cell through the positive heat-conducting insulating layer and the negative heat-conducting insulating layer, and then is transferred to the liquid cooling plate through the first heat dissipation plate and the second heat dissipation plate. In a possible implementation, one end of the first heat dissipation plate is bent between the at least one side plate and the liquid cooling plate, and one end of the second heat dissipation plate is bent between the at least one side plate and the liquid cooling plate. Therefore, the battery cell can be mounted on the liquid cooling plate through the first heat dissipation plate and the second heat dissipation plate, the heat of the shell of the battery cell is completely transferred to the liquid cooling plate through the first heat dissipation plate and the second heat dissipation plate, and the size of the battery pack is small. In another possible implementation, one end of the first heat dissipation plate is bent to a side surface of the liquid cooling plate facing the battery cell and extends on the liquid cooling plate in a direction away from the battery cell, and one end of the second heat dissipation plate is bent to a side surface of the liquid cooling plate facing the battery cell and extends on the liquid cooling plate in a direction away from the battery cell. Therefore, the battery cell can be transferred to the liquid cooling plate through the side plate of the shell facing the liquid cooling plate, and the first heat dissipation plate and the second heat dissipation plate.

[0016] The battery cell of the application can be a square battery cell. Specifically, the plurality of side plates of the shell includes two opposite side plates and four side plates connected in sequence. The four side plates are located between the two side plates and are perpendicular to the two side plates. In a possible implementation, the positive pole and the negative pole can be arranged on one of the two side plates, that is, the positive pole and the negative pole are located on the same side of the battery cell. The other side plate of the two side plates is in contact with the liquid cooling plate. In another possible implementation, the positive pole can be arranged on one of the two side plates, and the negative pole can be arranged on the other side plate of the two side plates, that is, the positive pole and the negative pole are arranged on opposite sides of the battery cell. Any one of the four side plates is in contact with the liquid cooling plate.

[0017] In a third aspect, the present application also provides a battery pack. The battery pack comprises the battery pack of the second aspect and a power converter, wherein the power converter is configured to convert power output by an external power source and output the converted power to the battery pack. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 A schematic diagram of a battery pack provided by an embodiment of the present application;

[0019] Figure 2 A schematic diagram of a battery cell provided by an embodiment of the present application;

[0020] Figure 3 A schematic diagram of a cell pack provided by an embodiment of the present application;

[0021] Figure 4 A schematic diagram of a battery cell provided by an embodiment of the present application;

[0022] Figure 5 A schematic diagram of a cell pack provided by an embodiment of the present application;

[0023] Figure 6 A schematic diagram of a battery cell provided by an embodiment of the present application;

[0024] Figure 7 A schematic diagram of a positive electrode pin and a positive electrode heat-conducting insulation layer provided by an embodiment of the present application;

[0025] Figure 8 A schematic diagram of a negative electrode pin and a negative electrode heat-conducting insulation layer provided by an embodiment of the present application;

[0026] Figure 9 A schematic diagram of a battery cell provided by an embodiment of the present application;

[0027] Figure 10 A schematic diagram of a battery cell provided by an embodiment of the present application;

[0028] Figure 11 A schematic diagram of a first heat-dissipating plate and a second heat-dissipating plate provided by an embodiment of the present application;

[0029] Figure 12 A schematic diagram of a battery cell provided by an embodiment of the present application.

[0030] REFERENCE SIGNS:

[0031] 10 - battery pack

[0032] 11 - shell

[0033] 12 - battery cell

[0034] 13 - liquid cooling plate

[0035] 14 - positive electrode post

[0036] 15-negative post

[0037] 16-bottom plate

[0038] 121-housing

[0039] 122-core package

[0040] 123-positive connection tab

[0041] 124-negative connection tab

[0042] 125-first heat sink

[0043] 126-second heat sink

[0044] 127-flow channel

[0045] 1211-top plate

[0046] 1212-bottom plate

[0047] 1213-side plate

[0048] 1221-positive lug

[0049] 1222-negative lug

[0050] 1223-positive tab

[0051] 1224-separator

[0052] 1225-negative tab

[0053] 1231-positive pin

[0054] 1232-positive thermally conductive insulation layer

[0055] 1241-negative pin

[0056] 1242-negative thermally conductive insulation layer

[0057] 12211-positive tab

[0058] 12221-negative tab DETAILED DESCRIPTION

[0059] In order to make the purposes, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the drawings.

[0060] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in this specification and the appended claims, the singular forms "a," "an" and "the" include plural referents unless the context clearly dictates otherwise. The term "plurality" means two or more.

[0061] Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the application. Thus, the appearances of the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in additional embodiments," and the like in various places throughout this specification are not necessarily referring to the same embodiment, unless otherwise expressly specified. The terms "including," "containing," "having," and variations thereof mean "including but not limited to," unless expressly specified otherwise.

[0062] To facilitate the understanding of the battery pack and the energy storage system provided by the embodiments of the application, the application scenarios thereof are described below. The energy storage system of the application can be used in industrial and commercial energy storage and power station energy storage application scenarios. The industrial and commercial energy storage may, for example, include small industrial and commercial (small factories, etc.) energy storage, medium industrial and commercial energy storage, large industrial and commercial energy storage, light storage charging station energy storage, small and medium micro-grid (island, etc.) energy storage, etc. The power station energy storage may, for example, include wind light storage power station, power grid storage power station, large micro-grid power station, etc. In addition, the energy storage device can also be used in data center, vehicle charging station and other application scenarios. The energy storage device contains a power converter and at least one battery pack, and the power converter is used to output the power energy output by the external power supply to the at least one battery pack after power conversion. Figure 1 A schematic diagram of the battery pack provided by the embodiments of the application is shown in FIG. 1. As shown in FIG. 1, the battery pack 10 specifically includes a shell 11 and at least one battery cell 12, and the at least one battery cell 12 is located in the shell 11. Further, the battery pack 10 can also include a liquid cooling plate 13, which is arranged at the bottom of the battery pack 10, so as to cool the battery cell 12 by the bottom cooling mode. Figure 1

[0063] In the current battery pack, the internal heat of the battery cell mainly comes from the core package, and the heat of the core package is concentrated at the tab. However, the tab is only connected with the pole, and in order to avoid the direct transmission of current from the tab to the shell, the tab is arranged at a distance from the shell of the battery cell. Therefore, the upper half of the internal heat of the battery cell cannot be transmitted in time, resulting in a large temperature difference between the upper half and the lower half, and the thermal uniformity in the battery cell is poor. ​

[0064] Therefore, the present application provides a battery cell, a battery pack, and an energy storage system to improve the heat dissipation efficiency inside the battery cell and achieve uniform temperature heat dissipation of the battery cell, thereby improving the heat dissipation efficiency and service life of the battery pack.

[0065] Figure 2 This is a schematic diagram of a battery cell provided in an embodiment of the present application. Figure 1 and Figure 2 As shown, the battery cell 12 includes a shell 121 and at least one core package 122, and the at least one core package 122 is located in the shell 121. Specifically, the shell 121 can be a square shell, which includes a top plate 1211 and a bottom plate 1212 arranged opposite to each other, and four side plates 1213 located between the top plate 1211 and the bottom plate 1212. The four side plates 1213 are connected in sequence, and the four side plates 1213 are arranged perpendicular to the top plate 1211. Therefore, the top plate 1211, the bottom plate 1212 and the four side plates 1213 enclose a receiving cavity, and the at least one core package 122 is located in the receiving cavity. The battery cell 12 also includes a positive electrode column 14 and a negative electrode column 15. The positive electrode column 14 can be located on the top plate 1211, the bottom plate 1212 or the side plate 1213, and the negative electrode column 15 can be located on the top plate 1211, the bottom plate 1212 or the side plate 1213. That is to say, the positive electrode column 14 and the negative electrode column 15 can be located on the same side of the battery cell 12, or the positive electrode column 14 and the negative electrode column 15 can be located on opposite sides of the battery cell 12, or the positive electrode column 14 and the negative electrode column 15 can be located on adjacent sides of the battery cell 12. In addition, a bottom support plate 16 is also provided in the shell 121. The core package 122 can be placed on the bottom support plate 16 to avoid direct contact between the core package 122 and the shell 121. It should be noted that the words expressing position and direction (such as top, bottom, side, left, right, etc.) described in the embodiments of the present application are all explained with reference to the accompanying drawings as an example, but changes can be made as needed, and all changes are included in the scope of protection of this application.

[0066] The core package 122 may be a wound core package or a laminated core package. Figure 3 A schematic diagram of the core package provided in the embodiment of the present application. Figure 3 As shown, in one embodiment, the core package 122 is a wound core package, which may include a positive electrode sheet 1223, a separator 1224 and a negative electrode sheet 1225, the separator 1224 is located between the positive electrode sheet 1223 and the negative electrode sheet 1225, and the positive electrode sheet 1223, the separator 1224 and the negative electrode sheet 1225 are wound to form the core package 122, which is a cylindrical core package. Figure 4 This is another schematic diagram of a battery cell provided in an embodiment of the present application. Figure 5 This is another schematic diagram of the core package provided in the embodiment of the present application. Figure 4 and Figure 5As shown, in another embodiment, the core pack 122 is a laminated core pack, which can include a plurality of positive electrode sheets 1223, a plurality of separators 1224 and a plurality of negative electrodes. The aforementioned plurality of positive electrode sheets 1223 and the aforementioned plurality of negative electrode sheets 1225 are alternately stacked, and the separators 1224 are arranged between adjacent positive electrode sheets 1223 and negative electrode sheets 1225, and the core pack 122 is a square core pack.

[0067] In the embodiments of the present application, the core pack 122 has a positive electrode tab 1221 and a negative electrode tab 1222. In the shell 121, the positive electrode tab 1221 is directed to one plate which is not provided with any one of the poles, and the negative electrode tab 1222 is directed to the other plate which is not provided with any one of the poles. In the following, taking the example that the positive pole 14 and the negative pole 15 are arranged on the same side or opposite sides of the shell 121 for detailed description.

[0068] In one embodiment, the positive pole 14 and the negative pole 15 are arranged on the same side of the shell 121, specifically, the positive pole 14 and the negative pole 15 can be arranged together on the top plate 1211, or arranged together on the bottom plate 1212. In the battery cell 12 of the present application, as shown in Figure 2 and Figure 4 As shown, the positive pole 14 and the negative pole 15 can be located on the same side of the battery cell 12. Figure 6 Another schematic diagram of the battery cell provided in the embodiments of the present application is shown. As shown in Figure 6 As shown, the positive pole 14 and the negative pole 15 can also be located on the two sides of the battery cell 12.

[0069] Please continue to refer to Figure 2 and Figure 4 , taking the example that the positive pole 14 and the negative pole 15 are located on the top plate 1211. The core pack 122 has two oppositely arranged end faces, as shown in Figure 2 and Figure 4 , the left end face S1 of the core pack 122 and the right end face S2 of the core pack 122, wherein the left end face S1 is oppositely arranged with one of the four side plates 1213, and the left end face S1 is provided with the positive electrode tab 1221. The right end face S2 is oppositely arranged with another one of the four side plates 1213, and the right end face S2 is provided with the negative electrode tab 1222. In this embodiment, the aforementioned one side plate 1213 and the other side plate 1213 can be oppositely arranged, as shown in Figure 2 and Figure 4 . Alternatively, the aforementioned one side plate 1213 and the other side plate 1213 can also be adjacently arranged.

[0070] In one embodiment, the tabs of the core pack 122 can be full-tab structure. Taking the example of a wound core pack, as shown in Figure 3As shown, the manufacturing process of the full-electrode ear structure includes: cutting one side of the positive electrode sheet 1223 into multiple positive electrode ear sheets 12211, and cutting one side of the negative electrode sheet 1225 into multiple negative electrode ear sheets 12221; stacking the positive electrode sheet 1223, the separator 1224 and the negative electrode sheet 1225 in sequence and winding them into a cylindrical core package, wherein the aforementioned multiple positive electrode ear sheets 12211 and the aforementioned multiple negative electrode ear sheets 12221 are relatively located on both sides of the separator 1224. The plurality of positive electrode tabs 12211 are bent and flattened toward the left end surface S1 of the core package 122, where the positive electrode tab 12211 is located, thereby forming a full-tab structure (i.e., positive electrode tab 1221) covering the left end surface S1. Furthermore, the plurality of negative electrode tabs 12221 are bent and flattened toward the right end surface S2 of the core package 122, where the negative electrode tab 12221 is located, thereby forming a full-tab structure (i.e., negative electrode tab 1222) covering the right end surface S2. The positive and negative electrode tabs 1221 and 1222 of the full-tab structure of the wound core package are located on either side of the core package 122. That is, the positive electrode tab 1221 covers the surface of the left end surface S1 of the core package 122, and the negative electrode tab 1222 covers the surface of the right end surface S2 of the core package 122. In another embodiment, the core package 122 is a laminated core package. The positive electrode tab and the negative electrode tab of the core package 122 can be located on opposite sides of the core package 122 , or the positive electrode tab and the negative electrode tab can also be located on adjacent sides of the core package 122 .

[0071] It should be noted that, in the core package 122, the surface of the core package 122 covered by the tab refers to the surface of the tab on the core package 122, not the plane where the tab is located. Taking a wound core package as an example, in one embodiment, the positive electrode sheet 1223, the separator 1224, and the negative electrode sheet 1225 are wound to form a solid cylindrical core package, and the positive tab 1221 can completely cover one end surface of the core package 122, and the negative tab 1222 can completely cover the other end surface of the core package 122. In another embodiment, the positive electrode sheet 1223, the separator 1224, and the negative electrode sheet 1225 are wound to form a hollow cylindrical core package, and the positive tab 1221 can cover the surface of one end surface of the core package 122, and the negative tab 1222 can completely cover the surface of the other end surface of the core package 122, that is, the full positive electrode tab and the full negative electrode tab do not cover the hollow area.

[0072] like Figure 5 As shown, in another embodiment, the tabs of the core pack 122 can also be a multi-tab structure. Taking a laminated core pack as an example, the core pack 122 includes multiple positive electrode sheets 1223, multiple separators 1224, and multiple negative electrode sheets 1225, which are stacked in this order. The positive electrode sheets 1223 are provided with multiple positive tabs 12211, and the negative electrode sheets 1225 are provided with multiple negative tabs 12221.

[0073] likeFigure 2 and Figure 4 As shown in FIGS. 12, 13, 14 and 15, the battery cell 12 further comprises a positive electrode pin 1231, a positive electrode heat-conducting insulation layer 1232, a negative electrode pin 1241 and a negative electrode heat-conducting insulation layer 1242. Figure 7 FIGS. 16 and 17 are schematic diagrams of the positive electrode pin and the positive electrode heat-conducting insulation layer provided in the embodiments of the present application. As shown in FIGS. 16 and 17, the positive electrode pin 1231 and the positive electrode heat-conducting insulation layer 1232 form a positive electrode connecting piece 123. Specifically, the positive electrode pin 1231 electrically connects the positive electrode tab 1221 and the positive electrode post 14. The positive electrode heat-conducting insulation layer 1232 is connected to a side surface of the positive electrode pin 1231 away from the positive electrode tab 1221, and the positive electrode heat-conducting insulation layer 1232 is in contact with the one side plate 1213. Figure 2 , Figure 4 and Figure 7 As shown in FIGS. 16 and 17, the positive electrode pin 1231 and the positive electrode heat-conducting insulation layer 1232 form a positive electrode connecting piece 123. Specifically, the positive electrode pin 1231 electrically connects the positive electrode tab 1221 and the positive electrode post 14. The positive electrode heat-conducting insulation layer 1232 is connected to a side surface of the positive electrode pin 1231 away from the positive electrode tab 1221, and the positive electrode heat-conducting insulation layer 1232 is in contact with the one side plate 1213. Figure 8 FIGS. 18 and 19 are schematic diagrams of the negative electrode pin and the negative electrode heat-conducting insulation layer provided in the embodiments of the present application. As shown in FIGS. 18 and 19, the negative electrode pin 1241 and the negative electrode heat-conducting insulation layer 1242 form a negative electrode connecting piece 124. The negative electrode pin 1241 electrically connects the negative electrode tab 1222 and the negative electrode post 15. The negative electrode heat-conducting insulation layer 1242 is connected to a side surface of the negative electrode pin 1241 away from the negative electrode tab 1222, and the negative electrode heat-conducting insulation layer 1242 is in contact with the other side plate 1213. Figure 2 , Figure 4 and Figure 8 As shown in FIGS. 18 and 19, the negative electrode pin 1241 and the negative electrode heat-conducting insulation layer 1242 form a negative electrode connecting piece 124. The negative electrode pin 1241 electrically connects the negative electrode tab 1222 and the negative electrode post 15. The negative electrode heat-conducting insulation layer 1242 is connected to a side surface of the negative electrode pin 1241 away from the negative electrode tab 1222, and the negative electrode heat-conducting insulation layer 1242 is in contact with the other side plate 1213.

[0074] In the battery cell 12 of the present application, the positive electrode pin 1231 electrically connects the positive electrode tab 1221 and the positive electrode post 14, and the positive electrode heat-conducting insulation layer 1232 can transfer the heat of the positive electrode tab 1221 to the shell 121. The negative electrode pin 1241 electrically connects the negative electrode tab 1222 and the negative electrode post 15, and the negative electrode heat-conducting insulation layer 1242 can transfer the heat of the negative electrode tab 1222 to the shell 121. Thus, the heat of the cell pack 122 can be transferred to the shell 121, the heat dissipation efficiency of the cell pack 122 is improved, the uniform heat dissipation of the battery cell 12 is achieved, and the heat dissipation efficiency and the service life of the battery pack 10 are improved.

[0075] In the present application, since the positive electrode tab 1221 does not face the positive electrode post 14 and the negative electrode tab 1222 does not face the negative electrode post 15, the positive electrode pin 1231 and the negative electrode pin 1241 need to be arranged in a bent shape. As shown in FIGS. 16 and 18, the positive electrode pin 1231 can be in an L shape. That is, one end of the positive electrode pin 1231 is located between the positive electrode tab 1221 and the positive electrode heat-conducting insulation layer 1232, that is, one side surface is connected to the positive electrode tab 1221 and the other side surface is connected to the positive electrode heat-conducting insulation layer 1232. The other end of the positive electrode pin 1231 is connected to the positive electrode post 14. The side surface of the positive electrode heat-conducting insulation layer 1232 away from the positive electrode pin 1231 is in contact with the one side plate 1213. Figure 7 As shown in FIGS. 18 and 19, the negative electrode pin 1241 and the negative electrode heat-conducting insulation layer 1242 form a negative electrode connecting piece 124. The negative electrode pin 1241 electrically connects the negative electrode tab 1222 and the negative electrode post 15. The negative electrode heat-conducting insulation layer 1242 is connected to a side surface of the negative electrode pin 1241 away from the negative electrode tab 1222, and the negative electrode heat-conducting insulation layer 1242 is in contact with the other side plate 1213. Figure 8As shown, similarly, the negative electrode pin 1241 can also be L-shaped. That is, one end of the negative electrode pin 1241 is located between the negative electrode tab 1222 and the negative electrode thermally conductive insulating layer 1242, that is, one side surface is connected with the negative electrode tab 1222, and the other side surface is connected with the negative electrode thermally conductive insulating layer 1242. The other end of the negative electrode pin 1241 is connected with the negative electrode post 15. The side surface of the negative electrode thermally conductive insulating layer 1242 away from the negative electrode pin 1241 is in contact with the other side plate 1213.

[0076] In the full-tab structure of the core package 122, the positive electrode pin 1231 can be fully welded with the positive electrode tab 1221, and the negative electrode pin 1241 can be fully welded with the negative electrode tab 1222, so that large-area connection can be achieved, and the transmission distance of the current can be reduced, so as to improve the uniformity of the power transmission performance in the core package 122. In addition, the positive electrode thermally conductive insulating layer 1232 can cover the part where the positive electrode pin 1231 is connected with the positive electrode tab 1221, and the negative electrode thermally conductive insulating layer 1242 can cover the part where the negative electrode pin 1241 is connected with the negative electrode tab 1222, so as to increase the heat transfer area between the positive electrode thermally conductive insulating layer 1232 and the positive electrode tab 1221, and between the negative electrode thermally conductive insulating layer 1242 and the negative electrode tab 1222, so as to improve the heat dissipation efficiency of the core package 122. In the multi-tab structure of the core package 122, the plurality of positive electrode tab pieces 12211 are respectively connected with the positive electrode pin 1231, and the plurality of negative electrode tab pieces 12221 are respectively connected with the negative electrode pin 1241.

[0077] In one embodiment, the area of the part where the positive electrode pin 1231 is located between the positive electrode thermally conductive insulating layer 1232 and the positive electrode tab 1221 is less than or equal to the area of the positive electrode thermally conductive insulating layer 1232. The area of the part where the negative electrode pin 1241 is located between the negative electrode thermally conductive insulating layer 1242 and the negative electrode tab 1222 is less than or equal to the area of the negative electrode thermally conductive insulating layer 1242. Therefore, the positive electrode thermally conductive insulating layer 1232 can increase the heat transfer area between the positive electrode pin 1231 and the positive electrode tab 1221, and the negative electrode thermally conductive insulating layer 1242 can increase the heat transfer area between the negative electrode pin 1241 and the negative electrode tab 1222, so as to increase the heat dissipation efficiency of the core package 122. In addition, the positive electrode thermally conductive insulating layer 1232 can insulate and isolate the positive electrode pin 1231 from the shell 121, and the negative electrode thermally conductive insulating layer 1242 can insulate and isolate the negative electrode pin 1241 from the shell 121, so as to avoid the conduction between the core package 122 and the shell 121.

[0078] In the above embodiment, the positive electrode heat-conducting insulation layer 1232 and the positive electrode pin 1231 can be fixedly connected by bonding. Alternatively, the positive electrode heat-conducting insulation layer 1232 can also be directly made on the surface of the positive electrode pin 1231 by a vapor deposition process. Similarly, the negative electrode heat-conducting insulation layer 1242 and the negative electrode pin 1241 can be fixedly connected by bonding. Alternatively, the negative electrode heat-conducting insulation layer 1242 can also be directly made on the surface of the negative electrode pin 1241 by a vapor deposition process. Therefore, the positive electrode heat-conducting insulation layer 1232 insulates the positive electrode pin 1231 from the shell 121 and can exchange heat, and the negative electrode heat-conducting insulation layer 1242 insulates the negative electrode pin 1241 from the shell 121 and can exchange heat.

[0079] In one embodiment, the positive electrode heat-conducting insulation layer 1232 can cover the above-mentioned one side plate 1213, and the negative electrode heat-conducting insulation layer 1242 can cover the above-mentioned another side plate 1213, so as to realize large-area heat transfer between the shell 121 and the heat-conducting insulation layer, and further improve the heat dissipation efficiency of the core package 122.

[0080] Figure 9 Another schematic view of the battery cell provided in the embodiment of the present application, Figure 10 Another schematic view of the battery cell provided in the embodiment of the present application, Figure 11 A schematic view of the first heat dissipation plate and the second heat dissipation plate provided in the embodiment of the present application. As shown in Figure 9 、 Figure 10 and Figure 11 mentioned one side plate 1213 away from the positive electrode heat-conducting insulation layer 1232 is provided with a first heat dissipation plate 125, and / or the above-mentioned another side plate 1213 away from the negative electrode heat-conducting insulation layer 1242 is provided with a second heat dissipation plate 126. The first heat dissipation plate 125 and the second heat dissipation plate 126 are used for heat transfer with the liquid cooling plate 13 in the battery pack 10, so as to transfer the heat of the shell 121 to the liquid cooling plate 13, and realize heat dissipation.

[0081] When the core package 122 is installed in the shell 11, one plate of the shell 121 not provided with any one pole can be in contact with the liquid cooling plate 13. Therefore, the battery cell 12 is installed on the liquid cooling plate 13, so as to dissipate the heat of the battery cell 12 through the liquid cooling plate 13.

[0082] When the battery pack 10 adopts a bottom cooling direction, the bottom of the battery cell 12 can be in contact with the liquid cooling plate 13. As shown in Figure 11As shown, specifically, in one embodiment, a first heat sink 125 covers one of the side plates 1213, and an end of the first heat sink 125 near the bottom plate 1212 can be bent between the battery cells 12 and the liquid cooling plate 13. In other words, the first heat sink 125 is L-shaped, wherein a portion 125a of the first heat sink 125 covers the outer surface of the side plate 1213, and another portion 125b of the first heat sink 125 is located between the bottom plate 1212 and the liquid cooling plate 13, i.e., one side surface of the other portion 125b contacts the bottom plate 1212, and the other side surface of the other portion 125b contacts the liquid cooling plate 13. Alternatively, a second heat sink 126 covers the other side plate 1213, and an end of the second heat sink 126 near the bottom plate 1212 is bent between the battery cells 12 and the liquid cooling plate 13. In other words, the second heat sink 126 is L-shaped, wherein a portion 126a of the second heat sink 126 covers the outer surface of the other side plate 1213, and another portion 126b of the second heat sink 126 is located between the bottom plate 1212 and the liquid cooling plate 13, that is, one side surface of the other portion 126b is in contact with the bottom plate 1212, and the other side surface of the other portion 126b is in contact with the liquid cooling plate 13. Figure 12 This is another schematic diagram of the battery cell provided in the embodiment of the present application. Figure 12 As shown, in another embodiment, a first heat sink 125 covers one of the side plates 1213. The end of the first heat sink 125 near the bottom plate 1212 bends to the side surface of the liquid cooling plate 13 facing the battery cells 12, and extends on the liquid cooling plate 13 away from the battery cells 12. In other words, the first heat sink 125 is L-shaped, wherein a portion 125a of the first heat sink 125 covers the outer surface of the side plate 1213, and another portion 125b of the first heat sink 125 is located on the side surface of the liquid cooling plate 13 facing the battery cells 12. That is, one surface of the other portion 125b contacts the liquid cooling plate 13, while the other surface does not contact the battery cells 12. Alternatively, a second heat sink 126 covers the other side plate 1213. The end of the second heat sink 126 near the bottom plate 1212 bends to the side surface of the liquid cooling plate 13 facing the battery cells 12, and extends on the liquid cooling plate 13 away from the battery cells 12. In other words, the second heat sink 126 is L-shaped, wherein a portion 126a of the second heat sink 126 covers the outer surface of the other side plate 1213, and another portion 126b of the second heat sink 126 is located on the side surface of the liquid-cooling plate 13 facing the battery cells 12. That is, one side surface of the second heat sink 126b is in contact with the liquid-cooling plate 13, while the other side surface is not in contact with the battery cells 12. In the above technical solution, the other portion 125b of the first heat sink 125 and the other portion 126b of the second heat sink 126 are used to contact and transfer heat with the liquid-cooling plate 13, thereby transferring the internal heat of the battery cells 12 to the liquid-cooling plate 13 through the heat sinks.

[0083] In the above embodiment, the portion of the first heat dissipation plate 125 in contact with the side plate 1213 completely covers the side plate 1213, and the portion of the second heat dissipation plate 126 in contact with the side plate 1213 completely covers the side plate 1213. In other words, the area of ​​the portion of the first heat dissipation plate 125 in contact with the side plate 1213 is equal to the area of ​​the side plate 1213, and the area of ​​the portion of the second heat dissipation plate 126 in contact with the side plate 1213 is equal to the area of ​​the side plate 1213.

[0084] Of course, in other embodiments, the portion of the first heat dissipation plate 125 that contacts the one side plate 1213 may also cover at least a portion of the one side plate 1213, and the portion of the second heat dissipation plate 126 that contacts the other side plate 1213 may also cover at least a portion of the other side plate 1213. In other words, the area of ​​the portion of the first heat dissipation plate 125 that contacts the one side plate 1213 is smaller than the area of ​​the one side plate 1213, and the area of ​​the portion of the second heat dissipation plate 126 that contacts the other side plate 1213 is smaller than the area of ​​the other side plate 1213.

[0085] like Figure 11 As shown, the first heat sink 125 and the second heat sink 126 are respectively provided with a flow channel 127, into which a liquid cooling medium (such as water or oil) can be injected. The heat on the surface of the shell 121 of the battery cell 12 is taken away by the circulation of the cooling medium in the flow channel 127, thereby achieving the purpose of heat dissipation. Specifically, the positive electrode thermal insulation layer 1232 and the negative electrode thermal insulation layer 1242 transfer the heat of the core package 122 to the shell 121, and then transfer it to the first heat sink 125 and the second heat sink 126. After the liquid cooling medium in the first heat sink 125 and the second heat sink 126 absorbs heat, a high-temperature area is formed. Subsequently, the cooling medium after absorbing heat flows toward the low-temperature area in the flow channel 127, that is, flows toward the bottom of the battery cell 12, and exchanges heat with the liquid cooling plate 13 at the bottom of the battery cell 12. By absorbing and releasing heat of the cooling medium, the heat of the shell 121 can be brought from the high-temperature area to the low-temperature area for dissipation, thereby improving the heat dissipation performance inside the battery cell 12 and achieving temperature consistency inside the battery cell 12.

[0086] In the present application, the material for making the heat dissipation plate is not limited, for example, the first heat dissipation plate 125 can include a metal heat dissipation plate or a metal matrix composite heat dissipation plate, and the second heat dissipation plate 126 can include a metal heat dissipation plate or a metal matrix composite heat dissipation plate. Specifically, the heat dissipation plate can be a metal heat dissipation plate, such as an aluminum heat dissipation plate or a copper heat dissipation plate. Alternatively, the heat dissipation plate can be a metal matrix composite heat dissipation plate. The metal matrix composite heat dissipation plate uses a metal with high thermal conductivity as a matrix, and uses inorganic non-metallic fibers, whiskers, particles or nanoparticles with high thermal conductivity as reinforcing bodies. The matrix and the reinforcing bodies are combined and made into a metal matrix composite heat dissipation plate. The matrix can include copper-based, magnesium-based or aluminum-based, etc.

[0087] The positive electrode heat-conducting insulating layer 1232 can include at least one of an epoxy resin heat-conducting insulating layer, a silicone rubber heat-conducting insulating layer, a silicone grease heat-conducting insulating layer, and an insulating ceramic heat-conducting insulating layer, and the negative electrode heat-conducting insulating layer 1242 can include at least one of an epoxy resin heat-conducting insulating layer, a silicone rubber heat-conducting insulating layer, a silicone grease heat-conducting insulating layer, and an insulating ceramic heat-conducting insulating layer, which are not specifically limited here.

[0088] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed in the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A battery cell, characterized in that: It includes a shell, a core package, a positive electrode pin, a positive electrode thermal insulation layer, a negative electrode pin and a negative electrode thermal insulation layer, wherein: The shell includes a plurality of side panels, the plurality of side panels enclose an accommodating cavity, and the core package is located in the accommodating cavity; The housing is provided with a positive electrode column and a negative electrode column, and any one of the positive electrode column and the negative electrode column is located on any one of the multiple side plates; The core pack has a positive electrode tab and a negative electrode tab, the positive electrode tab faces one of the plurality of side plates where none of the poles is provided, and the negative electrode tab faces another of the plurality of side plates where none of the poles is provided; The positive electrode pin is electrically connected to the positive electrode tab and the positive electrode column, the positive electrode thermally conductive insulating layer is provided on a side of the positive electrode pin away from the positive electrode tab, and the positive electrode thermally conductive insulating layer is in contact with the one side plate; The negative electrode pin is electrically connected to the negative electrode ear and the negative electrode column. The negative electrode thermally conductive insulating layer is arranged on a side of the negative electrode pin away from the negative electrode ear. The negative electrode thermally conductive insulating layer is in contact with the other side plate.

2. The battery cell according to claim 1, wherein: The area of ​​the portion of the positive electrode pin located between the positive electrode thermally conductive insulating layer and the positive electrode tab is less than or equal to the area of ​​the positive electrode thermally conductive insulating layer; The area of ​​a portion of the negative electrode pin located between the negative electrode thermally conductive insulating layer and the negative electrode tab is smaller than or equal to the area of ​​the negative electrode thermally conductive insulating layer.

3. The battery cell according to claim 1 or 2, characterized in that: The positive electrode pin is L-shaped, one end of the positive electrode pin is located between the positive electrode thermal insulation layer and the positive electrode tab, the other end of the positive electrode pin is located between the positive electrode column and the core package, and the positive electrode thermal insulation layer is located between the one side plate and the one end of the positive electrode pin; The negative electrode pin is L-shaped, one end of the negative electrode pin is located between the negative electrode thermal insulation layer and the negative electrode ear, the other end of the negative electrode pin is located between the negative electrode column and the core package, and the negative electrode thermal insulation layer is located between the other side plate and the one end of the negative electrode pin.

4. The battery cell according to any one of claims 1 to 3, characterized in that The positive electrode heat-conducting insulating layer covers the one side plate, and the negative electrode heat-conducting insulating layer covers the other side plate.

5. The battery cell according to claim 4, wherein: The core package includes two surfaces, and the two surfaces are arranged opposite to each other or adjacent to each other; The positive electrode tab is provided on one of the two surfaces, and the negative electrode tab is provided on the other of the two surfaces; the positive electrode tab is bent toward and covers the one surface, and the negative electrode tab is bent toward and covers the other surface; or, The positive electrode tab includes a plurality of positive electrode tabs, and the plurality of positive electrode tabs are electrically connected to the positive electrode pins respectively; the negative electrode tab includes a plurality of negative electrode tabs, and the plurality of negative electrode tabs are electrically connected to the negative electrode pins respectively.

6. The battery cell according to any one of claims 1 to 5, characterized in that A first heat dissipation plate is provided on a side of the one side plate away from the positive electrode heat conductive insulation layer, and a second heat dissipation plate is provided on a side of the other side plate away from the negative electrode heat conductive insulation layer.

7. The battery cell according to claim 6, wherein: The first heat sink comprises a metal heat sink or a metal-based composite heat sink; The second heat dissipation plate includes a metal heat dissipation plate or a metal-based composite heat dissipation plate.

8. The battery cell according to any one of claims 1 to 7, characterized in that The positive electrode thermal insulation layer includes at least one of an epoxy resin thermal insulation layer, a silicone rubber thermal insulation layer, a silicone grease thermal insulation layer and an insulating ceramic thermal insulation layer; The negative electrode thermally conductive insulating layer includes at least one of an epoxy resin thermally conductive insulating layer, a silicone rubber thermally conductive insulating layer, a silicone grease thermally conductive insulating layer and an insulating ceramic thermally conductive insulating layer.

9. A battery pack, characterized in that: The invention comprises a housing and at least one battery cell according to any one of claims 1 to 8, wherein the at least one battery cell is located in the housing.

10. The battery pack according to claim 9, wherein: The battery pack further includes a liquid cooling plate, and at least one side plate of the plurality of side plates on which any of the poles is not provided is in contact with the liquid cooling plate.

11. The battery pack according to claim 10, wherein: A first heat dissipation plate is provided on a side of the one side plate facing away from the positive electrode heat conductive insulation layer, and a second heat dissipation plate is provided on a side of the other side plate facing away from the negative electrode heat conductive insulation layer; One end of the first heat dissipation plate is bent between the at least one side plate and the liquid cooling plate, and one end of the second heat dissipation plate is bent between the at least one side plate and the liquid cooling plate; or, one end of the first heat dissipation plate is bent to a side surface of the liquid cooling plate facing the battery cell, and extends on the liquid cooling plate in a direction away from the battery cell, and one end of the second heat dissipation plate is bent to a side surface of the liquid cooling plate facing the battery cell, and extends on the liquid cooling plate in a direction away from the battery cell.

12. The battery pack according to claim 10 or 11, wherein: The plurality of side panels include two side panels arranged opposite to each other, and four side panels connected in sequence, wherein the four side panels are located between the two side panels and are arranged perpendicular to the two side panels; The positive electrode column and the negative electrode column are arranged on one of the two side plates, and the other side plate of the two side plates is in contact with the liquid cooling plate; or the positive electrode column is arranged on one of the two side plates, the negative electrode column is arranged on the other side plate of the two side plates, and any one of the four side plates is in contact with the liquid cooling plate.

13. An energy storage system, characterized in that: The energy storage system includes a battery pack and a power converter according to any one of claims 9 to 12, wherein the power converter is used to convert the electric energy output by an external power source into power and output the converted electric energy to the battery pack.

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