Battery cell, battery device, energy storage device, energy storage system and charging network

Abstract

The utility model provides a battery cell, a battery device, an energy storage device, an energy storage system and a charging network. A battery cell is included. A housing, an electrode assembly, and a first electrode terminal; the shell is provided with a first wall which is provided with a first lead-out hole; the electrode assembly is accommodated in the shell; the first electrode terminal is arranged on the first wall and comprises a first limiting piece and a terminal body which are arranged in a split mode and connected, the first limiting piece is located on the side, away from the electrode assembly, of the first wall, the terminal body penetrates through the first lead-out hole and is connected with the first limiting piece, and the terminal body is electrically connected with the electrode assembly; wherein the minimum over-current area S of the terminal body is 63mm < 2 >-491mm < 2 >, and the capacitance C of the single battery is 500Ah-1500Ah. According to the battery monomer, the material consumption of the terminal body can be reduced, the overcurrent capability of the terminal body can be improved, the manufacturing cost of the battery monomer is reduced, and the energy conversion efficiency of the battery monomer is improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery cell, a battery device, an energy storage device, an energy storage system and a charging network. Background Art

[0002] Energy conservation and emission reduction are the key to the sustainable development of the automobile industry. Electric vehicles have become an important part of the sustainable development of the automobile industry due to their advantages in energy conservation and environmental protection. For electric vehicles, battery technology is an important factor in their development.

[0003] Battery devices are widely used in portable electronic devices, electric vehicles, electric tools, drones, energy storage devices and other fields. In addition to considering the manufacturing cost of battery cells, the performance of battery cells is also an issue that cannot be ignored. Therefore, how to improve the performance of battery cells is a technical problem that needs to be solved urgently in battery technology. Utility Model Content

[0004] The embodiments of the present application provide a battery cell, a battery device, an energy storage device, an energy storage system and a charging network, which can improve the performance of the battery cell.

[0005] In a first aspect, an embodiment of the present application provides a battery cell, comprising a shell, an electrode assembly and a first electrode terminal; the shell has a first wall, and the first wall is provided with a first lead-out hole; the electrode assembly is accommodated in the shell; the first electrode terminal is provided on the first wall, and the first electrode terminal comprises a first limiter and a terminal body which are separately provided and connected, the first limiter is located on a side of the first wall away from the electrode assembly, the terminal body is passed through the first lead-out hole and connected to the first limiter, and the terminal body is electrically connected to the electrode assembly; wherein the minimum flow area S of the terminal body is 63 mm 2 -491mm 2 , the capacity C of the battery cell is 500Ah-1500Ah.

[0006] In the above technical solution, when the capacity of the battery cell is 500Ah-1500Ah and the minimum flow area of ​​the terminal body is greater than or equal to 63mm 2 When the capacity is 500Ah-1500Ah and the minimum flow area of ​​the terminal body is less than or equal to 491mm 2 When the terminal body is used, the material usage can be reduced, saving the manufacturing cost of the battery cell; therefore, when the capacity of the battery cell is 500Ah-1500Ah and the minimum flow area S of the terminal body is 63mm 2-491 mm 2 When it is [the above situation], it can take into account reducing the material usage of the terminal body and improving the overcurrent capacity of the terminal body, reducing the manufacturing cost of the battery cell and improving the energy conversion efficiency of the battery cell, and improving the service performance of the battery cell.

[0007] In some embodiments, the capacitance C of the battery cell and the minimum overcurrent area S of the terminal body satisfy any one of the following conditions: (1) 500 Ah ≤ C < 800 Ah, and 63 mm 2 ≤ S ≤ 283 mm 2 ; (2) 800 Ah ≤ C < 1200 Ah, and 95 mm 2 ≤ S ≤ 415 mm 2 ; (3) 1200 Ah ≤ C ≤ 1500 Ah, and 177 mm 2 ≤ S ≤ 491 mm 2 . In this way, different ranges of the capacitance of the battery cell correspond to different ranges of the minimum overcurrent area of the terminal body, and the larger the value of the capacitance range of the battery cell, the larger the value of the minimum overcurrent area range of the terminal body, so that the minimum overcurrent area of the terminal body has better overcurrent capacity at the corresponding capacitance, which helps to reduce the internal resistance of the battery cell and improve the energy conversion efficiency of the battery cell.

[0008] In some embodiments, the internal resistance R of the battery cell is 0.03 mΩ - 0.13 mΩ. In this way, when the minimum overcurrent area of the terminal body is 63 mm 2 -491 mm 2 , the capacitance of the battery cell is 500 Ah - 1500 Ah and the internal resistance of the battery cell is 0.03 mΩ - 0.13 mΩ, the battery cell can have a high energy conversion efficiency and improve the service performance of the battery cell.

[0009] In some embodiments, the first limiting member includes a first part and a second part. The materials of the first part and the second part are different. The first part is used to connect with an external component, the second part has the same material as the terminal body, and the second part is welded to the terminal body. The second part has the same material as the terminal body, so as to facilitate the welding connection between the terminal body and the second part, thereby improving the overcurrent capacity between the terminal body and the first limiting member, further reducing the internal resistance of the battery cell, and improving the energy conversion efficiency of the battery cell.

[0010] In some embodiments, the material of the first part is aluminum. In this way, the manufacturing cost of the first limiting member can be reduced.

[0011] In some embodiments, the material of the second part is copper. In this way, the conductivity of the second part and the terminal body can be improved, and the internal resistance of the first electrode terminal can be reduced.

[0012] In some embodiments, the material of the first part is aluminum and the material of the second part is copper. In this way, it is possible to balance the improvement of the conductivity of the first electrode terminal and the reduction of the manufacturing cost, and improve the energy conversion efficiency of the battery cell.

[0013] In some embodiments, the first limiting member is provided with a mounting hole. The terminal body includes a first current guiding portion and a second current guiding portion. The first current guiding portion passes through the mounting hole and is connected to the first limiting member. The second current guiding portion passes through the first lead-out hole. The first current guiding portion protrudes from one end of the second current guiding portion facing away from the electrode assembly. The position with the smallest current-carrying area of the terminal body is located at the first current guiding portion. By setting the position with the smallest current-carrying area of the terminal body at the first current guiding portion, the minimum current-carrying area of the first current guiding portion is 63 mm 2 -491 mm 2 , so that the first current guiding portion has a strong current-carrying capacity, thereby reducing the current-carrying internal resistance of the first electrode terminal, further reducing the internal resistance of the battery cell, and improving the energy conversion efficiency of the battery cell.

[0014] In some embodiments, the second current guiding portion has a first abutting surface. The first current guiding portion protrudes from the first abutting surface. The first current guiding portion has a second abutting surface facing the first abutting surface. The first abutting surface and the second abutting surface cooperate to clamp a part of the first limiting member to limit the movement of the first limiting member relative to the terminal body in the thickness direction of the first wall. In this way, the first current guiding portion and the second current guiding portion cooperate to clamp a part of the first limiting member to realize the connection between the terminal body and the first limiting member, reduce the risk of the first limiting member detaching from the terminal body, and improve the structural stability of the first electrode terminal.

[0015] In some embodiments, the first current guiding portion includes a first current guiding section and a second current guiding section. The first current guiding section protrudes from the first abutting surface. The first current guiding section connects the second current guiding section and the second current guiding portion. One end of the second current guiding section close to the first current guiding section forms the second abutting surface. The diameter of the first current guiding section is smaller than that of the second current guiding section. The position with the smallest current-carrying area of the terminal body is located at the first current guiding section. In this way, a part of the first limiting member extends between the first abutting surface of the second current guiding portion and the second abutting surface of the second current guiding section and is arranged close to the first current guiding section, so that the second current guiding section and the second current guiding portion cooperate to clamp a part of the first limiting member, making the connection between the first limiting member and the terminal body more stable; the minimum current-carrying area of the first current guiding section is the minimum current-carrying area of the terminal body, and the minimum current-carrying area of the first current guiding section is 63 mm 2 -491 mm 2 , so that the terminal body has a high current-carrying capacity, reduces the internal resistance of the battery cell, and improves the energy conversion efficiency of the battery cell.

[0016] In some embodiments, the difference between the diameter of the second diversion section and the diameter of the first diversion section is D1, where 1 mm ≤ D1 ≤ 10 mm. When D1 ≥ 1 mm, the second abutting surface of the second diversion section can have a larger area in contact with the first limiting member, thereby enhancing the limiting effect of the first abutting surface and the second abutting surface on the first limiting member, and enhancing the connection stability between the first limiting member and the terminal body; when D1 ≤ 10 mm, the material usage of the second diversion section can be reduced, the installation difficulty of the terminal body and the first limiting member can be reduced, and the setting cost of the second diversion section can be reduced; therefore, when 1 mm ≤ D1 ≤ 10 mm, the connection stability between the first limiting member and the terminal body can be enhanced while reducing the setting cost of the second diversion section.

[0017] In some embodiments, the first limiting member includes a first part and a second part. The materials of the first part and the second part are different. The first part is used for connecting with an external component, and the material of the second part is the same as that of the terminal body; the mounting hole includes a first hole section located in the first part and a second hole section located in the second part. The first hole section is closer to the electrode assembly than the second hole section. The part of the first diversion part located in the second hole section is welded to the second part. By setting the part of the first diversion part located in the second hole section to be welded to the second part, on the one hand, the connection strength between the first diversion part and the first limiting member can be enhanced; on the other hand, the welding connection between the first diversion part and the second part can improve the diversion ability of the first diversion part and the second part, thereby enhancing the diversion ability of the first electrode terminal, reducing the internal resistance of the first electrode terminal, thereby reducing the internal resistance of the battery cell, and enhancing the energy conversion efficiency of the battery cell.

[0018] In some embodiments, the minimum distance between the outer peripheral surface of the second part and the hole wall surface of the second hole section is D2, where 1 mm ≤ D2 ≤ 10 mm. When D2 ≥ 1 mm, the second part can have a larger size, which is convenient for welding the second part to the first diversion part, and is also convenient for increasing the contact area between the second part and the first part, and enhancing the diversion ability of the first limiting member; when D2 ≤ 10 mm, the material usage of the second part can be reduced, and the setting cost of the second part can be saved; therefore, when 1 mm ≤ D2 ≤ 10 mm, the diversion ability of the first limiting member can be enhanced while reducing the setting cost of the second part.

[0019] In some embodiments, along a first direction perpendicular to the thickness direction of the first wall, the minimum width of the second part is 14 mm - 30 mm. When the minimum width of the second part is greater than or equal to 14 mm, the contact area between the second part and the first part can be increased, enhancing the flow guiding ability between the first part and the second part; when the minimum width of the second part is less than or equal to 30 mm, the material usage of the second part can be reduced, saving the installation cost of the second part. Therefore, when the minimum width of the second part is 14 mm - 30 mm, it is possible to balance enhancing the flow guiding ability between the first part and the second part and saving the installation cost of the second part.

[0020] In some embodiments, the battery cell further includes a second electrode terminal having a polarity opposite to that of the first electrode terminal. The second electrode terminal is disposed on the first wall and is spaced apart from the first electrode terminal along a first direction perpendicular to the thickness direction of the first wall; the first part has a first surface facing away from the electrode assembly, and the first surface is located on a side of the second part facing away from the second electrode terminal. Along the first direction, the width of the first surface is 10 mm - 100 mm. When the width of the first surface is greater than or equal to 10 mm, the first part has a sufficient size to contact external components, facilitating the input or output of electrical energy of the battery cell through the external components and reducing the installation difficulty of the battery cell; when the width of the first surface is less than or equal to 100 mm, the material usage of the first part can be reduced, saving the installation cost of the first part; therefore, when the width of the first surface is 10 mm - 100 mm, it is possible to balance reducing the installation difficulty of the battery cell and saving the installation cost of the first part.

[0021] In some embodiments, a receiving groove is provided on a side of the first part facing away from the electrode assembly. One end of the first hole section away from the electrode assembly extends to the bottom surface of the receiving groove, and at least a part of the second part is received in the receiving groove. In this way, the first hole section communicates with the receiving groove, facilitating the first flow guiding portion to pass through the first hole section and extend into the receiving groove to connect with the second part, reducing the installation difficulty of the first flow guiding portion. At least a part of the second part is received in the receiving groove, which can increase the contact area between the second part and the wall surface of the receiving groove, thereby increasing the flow guiding area between the second part and the first part and enhancing the flow guiding ability between the first part and the second part.

[0022] In some embodiments, in a projection plane perpendicular to the thickness direction of the first wall, the sum of the projected areas of the orthographic projection of the second part and the orthographic projection of the first flow guiding portion is less than or equal to the projected area of the orthographic projection of the second flow guiding portion. In this way, the second flow guiding portion can have a larger flow-through area, reducing the influence of the second flow guiding portion on the flow-through ability of the first electrode terminal.

[0023] In some embodiments, the terminal body further includes a third current guiding portion located on the side of the first wall facing the electrode assembly. The second current guiding portion connects the third current guiding portion and the first current guiding portion. The third current guiding portion and the first limiting member cooperate to clamp the first wall. In this way, the third current guiding portion and the first limiting member cooperate to clamp the first wall, improving the connection stability between the first electrode terminal and the first wall.

[0024] In some embodiments, the first current guiding portion, the second current guiding portion, and the third current guiding portion are integrally formed. In this way, the difficulty of arranging the first current guiding portion, the second current guiding portion, and the third current guiding portion is reduced, and the arrangement cost of the first current guiding portion, the second current guiding portion, and the third current guiding portion is reduced.

[0025] In some embodiments, the ratio of the capacitance C of the battery cell to the minimum current-carrying area S of the terminal body is 2 Ah / mm 2 -7 Ah / mm 2 . In this way, the battery cell corresponding to the capacitance can have a relatively large minimum current-carrying area of the terminal body, thereby improving the current-carrying capacity of the first electrode terminal, reducing the internal resistance of the battery cell, and improving the energy conversion efficiency of the battery cell.

[0026] In some embodiments, the battery cell further includes a second electrode terminal having a polarity opposite to that of the first electrode terminal. The first wall is provided with a second lead-out hole, and the second lead-out hole and the first lead-out hole are spaced apart in a first direction. The second electrode terminal passes through the second lead-out hole, and the first direction is perpendicular to the thickness direction of the first wall; along the first direction, the ratio of the center distance between the second lead-out hole and the first lead-out hole to the size of the electrode assembly is 0.35-0.8. In this way, the distance between the first electrode terminal and the second electrode terminal is relatively close, so that the internal resistance between the first electrode terminal and the second electrode terminal can be reduced, and the energy conversion efficiency of the battery cell is improved.

[0027] In some embodiments, the battery cell further includes a connecting member. The electrode assembly is provided with a tab. At least a part of the connecting member is located between the tab and the terminal body. The tab, the connecting member, and the terminal body are welded to form a first connecting portion, and the first connecting portion connects the connecting member, the tab, and the terminal body. In this way, the connection between the tab and the terminal body is more stable, improving the connection stability between the tab and the terminal body.

[0028] In some embodiments, the cross-section of the terminal body where the minimum current-carrying area S is located is a circular surface, the diameter of the circular surface is 9 mm - 25 mm, and the cross-section is perpendicular to the thickness direction of the first wall. When the diameter of the circular surface is greater than or equal to 9 mm, the first electrode terminal can have a larger current-carrying area, reducing the internal resistance of the battery cell and improving the energy conversion efficiency of the battery cell; when the diameter of the circular surface is less than or equal to 25 mm, the setting cost of the terminal body can be saved; therefore, when the diameter of the circular surface is 9 mm - 25 mm, both the energy conversion efficiency of the battery cell can be improved and the setting cost of the terminal body can be saved.

[0029] In a second aspect, an embodiment of the present application provides a battery device, including the battery cell provided in any one of the embodiments of the first aspect.

[0030] In some embodiments, the battery device includes a busbar component and a plurality of battery cells. The busbar component is electrically connected to the plurality of battery cells. The first limiting member of the first electrode terminal of at least one battery cell is connected to the busbar component, and in the projection plane perpendicular to the thickness direction of the first wall, the area of the overlapping portion of the positive projection of the first limiting member and the positive projection of the busbar component connected to the first limiting member is 300 mm 2 -3000 mm 2 . In this way, the busbar component and the first limiting member can have a larger contact area, thereby improving the current-carrying capacity of the busbar component and the first limiting member, and facilitating the input or output of electric energy of the battery cell.

[0031] In a third aspect, an embodiment of the present application provides an energy storage device, including the battery cell provided in any one of the embodiments of the first aspect or the battery device provided in any one of the embodiments of the second aspect.

[0032] In a fourth aspect, an embodiment of the present application provides an energy storage system, including a power conversion device and the energy storage device provided in any one of the embodiments of the third aspect. The power conversion device is used to electrically connect a power generation device and the energy storage device.

[0033] In a fifth aspect, an embodiment of the present application provides a charging network, including a charging pile and the energy storage device provided in any one of the embodiments of the third aspect. The energy storage device is used to provide electric energy for the charging pile. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0035] Figure 1Schematic structural diagram of a vehicle provided by some embodiments of the present application;

[0036] Figure 2 Explosion diagram of a battery device provided by some embodiments of the present application;

[0037] Figure 3 Explosion diagram of a battery cell provided by some embodiments of the present application;

[0038] Figure 4 Schematic structural diagram of a battery cell provided by some embodiments of the present application;

[0039] Figure 5 is Figure 4 A - A cross - sectional view of;

[0040] Figure 6 is Figure 5 Partial enlarged view of area A in;

[0041] Figure 7 Assembly schematic diagram of a first electrode terminal and a first wall provided by some embodiments of the present application;

[0042] Figure 8 Explosion diagram of a first limiting member provided by some embodiments of the present application;

[0043] Figure 9 is Figure 7 Explosion diagram of the first electrode terminal and the first wall in;

[0044] Figure 10 is Figure 7 Partial enlarged view of area B in;

[0045] Figure 11 is Figure 9 Partial enlarged view of area C in;

[0046] Figure 12 is Figure 4 Partial enlarged view of area E in;

[0047] Figure 13 Schematic structural diagram of a first electrode terminal provided by some embodiments of the present application;

[0048] Figure 14 is Figure 8 Partial enlarged view of area F in;

[0049] Figure 15 Schematic structural diagram of a terminal body provided by some embodiments of the present application;

[0050] Figure 16 Assembly schematic diagram of an electrode terminal and a first wall provided by some embodiments of the present application;

[0051] Figure 17 Assembly schematic diagram of a terminal body and an electrode assembly provided by some embodiments of the present application;

[0052] Figure 18 Assembly schematic diagram of a battery cell and a bus bar component provided by some embodiments of the present application.

[0053] Icons: 1 - housing; 11 - shell; 12 - end cap; 13 - first wall; 131 - first lead-out hole; 132 - second lead-out hole;

[0054] 2 - electrode assembly; 21 - tab;

[0055] 3 - first electrode terminal; 31 - terminal body; 311 - first current-carrying part; 3111 - second abutting surface; 3112 - first current-carrying section; 3113 - second current-carrying section; 312 - second current-carrying part; 3121 - first abutting surface; 313 - third current-carrying part; 32 - first limiting part; 321 - first part; 3211 - receiving groove; 3212 - first surface; 322 - second part; 323 - mounting hole; 3231 - first hole section; 3232 - second hole section; 3a - electrode terminal; 3b - second electrode terminal;

[0056] 4 - connecting piece; 41 - first connecting part;

[0057] 10 - battery cell; 20 - box body; 201 - first box body; 202 - second box body; 30 - bus bar component; 100 - battery device; 200 - controller; 300 - motor; 1000 - vehicle; X - first direction; Y - second direction; Z - thickness direction of the first wall. Detailed implementation manners

[0058] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0059] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by those skilled in the technical field to which this application belongs; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification, claims and drawings of this application are intended to cover non-exclusive inclusion. The terms "first", "second", etc. in the specification, claims or drawings of this application are used to distinguish different objects and not to describe a specific order or primary-secondary relationship.

[0060] Reference to "embodiment" in this application means that a particular feature, structure or characteristic described in connection with the embodiment can be included in at least one embodiment of this application. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments.

[0061] The term "and / or" in this application is merely a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally represents an "or" relationship between the associated objects before and after.

[0062] In the embodiments of this application, the same reference numerals represent the same components, and for the sake of brevity, in different embodiments, the detailed description of the same components is omitted. It should be understood that the thickness, length, width and other dimensions of various components shown in the drawings of the embodiments of this application, as well as the overall thickness, length, width and other dimensions of the integrated device, are only for illustrative purposes and should not constitute any limitation to this application.

[0063] The "plurality" mentioned in this application refers to two or more (including two).

[0064] In the embodiments of this application, the battery cell can be a secondary battery, which refers to a battery cell that can activate the active material through charging and continue to be used after the battery cell discharges.

[0065] The battery cell includes but is not limited to lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium-metal batteries, sodium-metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-metal hydride batteries, nickel-cadmium batteries, lead-acid batteries, etc.

[0066] The battery cell generally includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode and a separator. During the charge and discharge process of the battery cell, active ions (such as lithium ions) are embedded and extracted back and forth between the positive electrode and the negative electrode. The separator is disposed between the positive electrode and the negative electrode, which can reduce the risk of short circuit between the positive and negative electrodes and at the same time allow the active ions to pass through.

[0067] In some embodiments, the positive electrode may be a positive electrode tab, and the positive electrode tab may include a positive electrode current collector and a positive electrode active material provided on at least one surface of the positive electrode current collector.

[0068] As an example, the positive electrode current collector has two surfaces opposite to each other in its own thickness direction, and the positive electrode active material is provided on any one or both of the two opposite surfaces of the positive electrode current collector.

[0069] As an example, the positive electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, or titanium, etc. may be used. The composite current collector may include a polymer material substrate layer and a metal layer. The composite current collector may be formed by forming a metal material (such as aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0070] As an example, the positive electrode active material may include at least one of the following materials: lithium-containing phosphate, lithium transition metal oxide, and their respective modified compounds. However, the present application is not limited to these materials, and other conventional materials that can be used as the positive electrode active material of the battery monomer may also be used. These positive electrode active materials may be used alone or in combination of two or more. Among them, examples of lithium-containing phosphate may include, but are not limited to, lithium iron phosphate (such as LiFePO4 (which may also be abbreviated as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium manganese iron phosphate, and a composite material of lithium manganese iron phosphate and carbon. Examples of lithium transition metal oxides may include, but are not limited to, lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi 1 / 3 Co 1 / 3Mn 1 / 3 O2 (which may also be abbreviated as NCM 333 ), LiNi 0.5 Co 0.2 Mn 0.3 O2 (which may also be abbreviated as NCM 523 ), LiNi 0.5 Co 0.25 Mn 0.25 O2 (which may also be abbreviated as NCM 211 ), LiNi 0.6 Co 0.2Mn 0.2 O2 (which can also be abbreviated as NCM 622 ), LiNi 0.8 Co 0.1 Mn 0.1 O2 (which can also be abbreviated as NCM 811 ), lithium nickel cobalt aluminum oxide (such as LiNi 0.85 Co 0.15 Al 0.05 O2), and at least one of its modified compounds, etc.

[0071] In some embodiments, the positive electrode can adopt porous metal. The porous metal can be porous nickel, porous copper, porous aluminum, porous alloy, etc. When the porous metal is used as the positive electrode, the positive electrode active material may not be provided on the surface of the porous metal, and of course, the positive electrode active material can also be provided. As an example, a lithium source material, potassium metal or sodium metal can also be filled and / or deposited in the porous metal, and the lithium source material is lithium metal and / or lithium-rich material.

[0072] In some embodiments, the negative electrode can be a negative electrode plate, and the negative electrode plate can include a negative electrode current collector.

[0073] As an example, the negative electrode current collector can adopt a metal foil, porous metal or composite current collector. For example, as the metal foil, aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel or titanium, etc. can be adopted. The porous metal can be porous nickel, porous copper, porous aluminum, porous alloy, etc. The composite current collector can include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (such as copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0074] As an example, the negative electrode plate can include a negative electrode current collector and a negative electrode active material provided on at least one surface of the negative electrode current collector.

[0075] As an example, the negative electrode current collector has two surfaces opposite to each other in its own thickness direction, and the negative electrode active material is provided on any one or both of the two opposite surfaces of the negative electrode current collector.

[0076] As an example, the negative electrode active material can be the negative electrode active material for battery cells known in the art. As an example, the negative electrode active material can include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. The silicon-based materials can be selected from at least one of elemental silicon, silicon oxides, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The tin-based materials can be selected from at least one of elemental tin, tin oxides, and tin alloys. However, the present application is not limited to these materials, and other conventional materials that can be used as the negative electrode active material of battery cells can also be used. These negative electrode active materials can be used alone or in combination of two or more.

[0077] In some embodiments, the material of the positive electrode current collector can be aluminum, and the material of the negative electrode current collector can be copper.

[0078] In some embodiments, the separator is a separator membrane. The separator membrane can be any known porous structure separator membrane with good chemical stability and mechanical stability.

[0079] As an example, the material of the separator membrane can include at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator membrane can be a single-layer film or a multi-layer composite film. When the separator membrane is a multi-layer composite film, the materials of each layer can be the same or different. The separator can be a separate component located between the positive and negative electrodes, or can be attached to the surfaces of the positive and negative electrodes.

[0080] In some embodiments, the separator is a solid electrolyte. The solid electrolyte is disposed between the positive electrode and the negative electrode, and simultaneously functions to transport ions and isolate the positive and negative electrodes.

[0081] In some embodiments, the battery cell further includes an electrolyte, and the electrolyte functions to conduct ions between the positive and negative electrodes. The electrolyte can be liquid, gel, or solid. Among them, the liquid electrolyte includes electrolyte salts and solvents.

[0082] In some embodiments, the electrolyte salts can include at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalate borate, lithium bis(oxalate) borate, lithium difluoro bis(oxalate) phosphate, and lithium tetrafluorooxalate phosphate.

[0083] In some embodiments, the solvent may include at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone and diethyl sulfone. The solvent may also be an ether solvent. The ether solvent may include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyltetrahydrofuran, diphenyl ether and crown ether.

[0084] Among them, the gel electrolyte includes a polymer as the skeletal network of the electrolyte, combined with an ionic liquid-lithium salt.

[0085] Among them, the solid electrolyte includes a polymer solid electrolyte, an inorganic solid electrolyte, and a composite solid electrolyte.

[0086] As an example, the polymer solid electrolyte may be polyether (polyethylene oxide), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, single-ion polymer, polyionic liquid-lithium salt, cellulose, etc.

[0087] As an example, the inorganic solid electrolyte may include oxide solid electrolytes (crystalline perovskite, sodium superionic conductor, garnet, amorphous LiPON film), sulfide solid electrolytes (crystalline lithium superionic conductor (lithium germanium phosphorus sulfur, argyrodite), amorphous sulfide), and one or more of halide solid electrolytes, nitride solid electrolytes and hydride solid electrolytes.

[0088] As an example, the composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to the polymer solid electrolyte.

[0089] In some embodiments, the electrode assembly is a wound structure. The positive electrode sheet and the negative electrode sheet are wound into a wound structure.

[0090] In some embodiments, the electrode assembly is a stacked structure.

[0091] As an example, multiple positive electrode sheets and multiple negative electrode sheets may be provided respectively, and the multiple positive electrode sheets and the multiple negative electrode sheets are alternately stacked.

[0092] As an example, multiple positive electrode sheets may be provided, and the negative electrode sheet is folded to form multiple folded segments stacked on each other, and a positive electrode sheet is clamped between adjacent folded segments.

[0093] As an example, both the positive electrode sheet and the negative electrode sheet are folded to form multiple folded segments stacked on each other.

[0094] As an example, a plurality of separator members may be provided and respectively disposed between any adjacent positive electrode plates or negative electrode plates.

[0095] As an example, the separator members may be continuously provided and disposed between any adjacent positive electrode plates or negative electrode plates by folding or winding.

[0096] In some embodiments, the shape of the electrode assembly may be cylindrical, flat, prismatic, or the like.

[0097] In some embodiments, the electrode assembly is provided with tabs, and the tabs can conduct current out of the electrode assembly. The tabs include a positive tab and a negative tab.

[0098] In some embodiments, the battery cell may include a housing. The housing is used to encapsulate components such as the electrode assembly and the electrolyte. The housing can be a steel shell, an aluminum shell, a plastic shell (such as polypropylene), a composite metal shell (such as a copper-aluminum composite shell), or an aluminum plastic film, etc.

[0099] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell of other shapes. The prismatic battery cell includes a square shell battery cell, a blade-shaped battery cell, a multi-prismatic battery cell, and the multi-prismatic battery cell is, for example, a hexagonal prismatic battery cell, etc.

[0100] The battery device mentioned in the embodiments of the present application may include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly may include a plurality of battery cells, and the plurality of battery cells are connected in series, parallel, or in a hybrid connection through a bus bar component.

[0101] In some embodiments, the battery cell assembly is generally formed by arranging a plurality of battery cells; as an example, the battery cell assembly can be a battery module, and the battery module is formed by arranging and fixing a plurality of battery cells to form an independent module.

[0102] As an example, the battery module can be formed by bundling a plurality of battery cells with cable ties.

[0103] In some embodiments, the battery device can be a battery pack, and the battery pack can include a box body and one or more battery cell assemblies, and the battery cell assemblies are accommodated in the box body.

[0104] As an example, the battery cell assembly can be a battery module, and the battery cell assembly can be accommodated in the box body by fixing the battery module in the box body.

[0105] As an example, the battery cell assembly can also be accommodated in the box body by directly fixing a plurality of battery cells to the box body.

[0106] As an example, the box may include a first box and a second box. The first box and the second box are buckled together to form a closed space inside the box to accommodate the battery cell assembly. The closed here means covered or closed, which can be sealed or unsealed. The first box can be a top cover or a bottom plate.

[0107] As an example, the box body may include a top cover, a frame and a bottom plate. The top cover and the bottom plate are respectively connected to the frame, so that a closed space is formed inside the box body to accommodate the battery cell assembly.

[0108] As an example, the box body can be used as a part of the chassis structure of the vehicle. For example, the top cover of the box body can become at least a part of the floor of the vehicle, or the frame of the box body can become at least a part of the cross beam and longitudinal beam of the vehicle.

[0109] In some embodiments, the battery device refers to an energy storage device, which includes a box body, at least one side of which is provided with a door. The energy storage device includes an energy storage container, an energy storage cabinet, and the like.

[0110] In the production and manufacturing of battery cells, the energy conversion efficiency of battery cells is an important indicator of battery performance. The higher the energy conversion efficiency of battery cells, the less energy loss of battery cells during charging and discharging. The internal resistance of battery cells is an important indicator affecting the energy conversion efficiency of battery cells. When charging and discharging battery cells, the internal resistance of battery cells will consume energy by generating heat, thereby affecting the energy conversion efficiency of battery cells.

[0111] In view of this, in order to reduce the internal resistance of the battery cell and improve the energy conversion efficiency of the battery cell, an embodiment of the present application provides a battery cell, including a shell, an electrode assembly and a first electrode terminal. The shell has a first wall, and the first wall is provided with a first lead-out hole. The electrode assembly is accommodated in the shell. The first electrode terminal is arranged on the first wall, and the first electrode terminal includes a first limiter and a terminal body that are separately arranged and connected. The first limiter is located on the side of the first wall away from the electrode assembly. The terminal body is passed through the first lead-out hole and connected to the first limiter. The terminal body is electrically connected to the electrode assembly. Among them, the minimum flow area S of the terminal body is 63mm 2 -491mm 2 , the capacity C of the battery cell is 500Ah-1500Ah.

[0112] In such a battery cell, when the capacity of the battery cell is 500Ah-1500Ah and the minimum flow area of ​​the terminal body is greater than or equal to 63mm 2When the time comes, the terminal body can have a large overcurrent area, thereby improving the overcurrent capacity of the electrode terminal, reducing the internal resistance of the battery cell, reducing the energy consumption of the battery cell during charging and discharging, and improving the energy conversion efficiency of the battery cell; when the capacitance is 500Ah - 1500Ah and the minimum overcurrent area of the terminal body is less than or equal to 491mm 2 When the time comes, it is possible to reduce the material usage of the terminal body and save the manufacturing cost of the battery cell; therefore, when the capacitance of the battery cell is 500Ah - 1500Ah and the minimum overcurrent area S of the terminal body is 63mm 2 -491mm 2 When the time comes, it is possible to balance reducing the material usage of the terminal body and improving the overcurrent capacity of the terminal body, reducing the manufacturing cost of the battery cell and improving the energy conversion efficiency of the battery cell, and improving the performance of the battery cell.

[0113] The technical solutions described in the embodiments of the present application are applicable to various electrical devices using battery cells and battery devices, such as mobile phones, portable devices, laptop computers, battery cars, electric toys, electric tools, vehicles, ships, and spacecrafts, etc. For example, spacecrafts include airplanes, rockets, space shuttles, and spaceships, etc.

[0114] For the convenience of description, the following embodiments take the electrical device as a vehicle as an example for description.

[0115] Please refer to Figure 1 , Figure 1 which is a schematic structural diagram of a vehicle 1000 provided by some embodiments of the present application. A battery device 100 is arranged inside the vehicle 1000, and the battery device 100 can be arranged at the bottom, head, or tail of the vehicle 1000. The battery device 100 can be used for power supply of the vehicle 1000. For example, the battery device 100 can be used as the operating power source of the vehicle 1000.

[0116] The vehicle 1000 may further include a controller 200 and a motor 300. The controller 200 is used to control the battery device 100 to supply power to the motor 300. For example, it is used for the working power requirements during the start, navigation, and driving of the vehicle 1000.

[0117] In some embodiments of the present application, the battery device 100 can not only be used as the operating power source of the vehicle 1000, but also be used as the driving power source of the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0118] Please refer to Figure 2 , Figure 2 which is an exploded view of a battery device 100 provided by some embodiments of the present application. The battery device 100 may include a box body 20 and battery cells 10, and the box body 20 is used to accommodate the battery cells 10.

[0119] Among them, a closed space for accommodating the battery cells 10 is formed inside the box body 20. The box body 20 can adopt various structures. In some embodiments, the box body 20 may include a first box body 201 and a second box body 202, and the first box body 201 and the second box body 202 are buckled with each other. The first box body 201 and the second box body 202 can be of various shapes, such as a cuboid, a cylinder, etc. The first box body 201 can be a hollow structure with one side open, and the second box body 202 can also be a hollow structure with one side open. The open side of the second box body 202 and the open side of the first box body 201 are buckled with each other, thus forming the box body 20 with a closed space. It can also be that the first box body 201 is a hollow structure with one side open, and the second box body 202 is a plate-like structure. The second box body 202 is buckled on the open side of the first box body 201, thus forming the box body 20 with an accommodation cavity.

[0120] In the battery device 100, the battery cells 10 can be one or multiple. If there are multiple battery cells 10, the multiple battery cells 10 can be connected in series, in parallel, or in a mixed connection. A mixed connection means that there are both series and parallel connections among the multiple battery cells 10. It can be that multiple battery cells 10 are first connected in series, in parallel, or in a mixed connection to form a battery module, and then multiple battery modules are connected in series, in parallel, or in a mixed connection to form a whole and are accommodated in the box body 20. It can also be that all the battery cells 10 are directly connected in series, in parallel, or in a mixed connection together, and then the whole formed by all the battery cells 10 is accommodated in the box body 20.

[0121] In some embodiments, the battery device 100 may further include a busbar component 30. The multiple battery cells 10 can be electrically connected through the busbar component 30 to achieve series, parallel, or mixed connection of the multiple battery cells 10. The busbar component 30 can be a metal conductor, such as copper, iron, aluminum, stainless steel, aluminum alloy, etc.

[0122] Please refer to Figure 3 , Figure 3 , which is an exploded view of the battery cell 10 provided by some embodiments of the present application. The battery cell 10 may include a housing 1 and an electrode assembly 2, and the electrode assembly 2 is accommodated in the housing 1.

[0123] In some embodiments, the housing 1 may include a shell 11 and an end cap 12. The shell 11 has an opening, and the end cap 12 closes the opening of the shell 11. Here, "closing" means covering or closing, which can be sealing or non-sealing.

[0124] The housing 11 is a component for accommodating the electrode assembly 2. The housing 11 can be a hollow structure with an opening formed at one end, or a hollow structure with openings formed at opposite ends. The housing 11 can be of various shapes, such as cylindrical, cuboid, etc. The material of the housing 11 can be various, such as copper, iron, aluminum, steel, aluminum alloy, etc. The electrode assembly 2 can be partially located inside the housing 11 or entirely located inside the housing 11.

[0125] The end cap 12 and the housing 11 together define a receiving space for accommodating the electrode assembly 2 and other components. The end cap 12 can be connected to the housing 11 by means such as welding, crimping, etc. to close the opening of the housing 11. The shape of the end cap 12 can be adapted to the shape of the housing 11. For example, if the housing 11 is a cuboid structure, the end cap 12 is a rectangular plate-like structure adapted to the housing 11. Another example is that if the housing 11 is a cylindrical structure, the end cap 12 is a circular plate-like structure adapted to the housing 11. The material of the end cap 12 can also be various, such as copper, iron, aluminum, steel, aluminum alloy, etc. The material of the end cap 12 and the housing 11 can be the same or different.

[0126] In an embodiment where the housing 11 has an opening formed at one end, one end cap 12 can be correspondingly provided. In an embodiment where the housing 11 has openings formed at opposite ends, two end caps 12 can be correspondingly provided. The two end caps 12 respectively close the two openings of the housing 11, and the two end caps 12 and the housing 11 together define the receiving space.

[0127] In some embodiments, the battery cell 10 may further include electrode terminals 3a. The electrode terminals 3a are provided on the outer shell 1 and are used to electrically connect to the tab 21 of the electrode assembly 2 to input or output the electrical energy of the battery cell 10. The electrode terminals 3a can be provided on the housing 11 of the outer shell 1 or on the end cap 12 of the outer shell 1. The electrode terminals 3a and the tab 21 can be directly connected. For example, the electrode terminals 3a and the tab 21 are welded. The electrode terminals 3a and the tab 21 can also be indirectly connected. For example, the electrode terminals 3a and the tab 21 are indirectly connected through a current collector member. The current collector member can be a metal conductor, such as copper, iron, aluminum, steel, aluminum alloy, etc.

[0128] As an example, as Figure 3 shown, one end of the housing 11 forms an opening, and there is one end cap 12 in the outer shell 1. One end cap 12 closes one opening of the housing 11. Two electrode terminals 3a are provided on the end cap 12. The two electrode terminals 3a are respectively a positive electrode terminal and a negative electrode terminal. One end of the electrode assembly 2 facing the end cap 12 forms a positive tab and a negative tab. The positive electrode terminal is electrically connected to the positive tab, and the negative electrode terminal is electrically connected to the negative tab.

[0129] Please refer to Figures 4 - 6 ,Figure 4 A schematic diagram of the structure of a battery cell 10 provided in some embodiments of the present application; Figure 5 for Figure 4 AA section view; Figure 6 for Figure 5 A partial enlarged view of the A area in the middle. The embodiment of the present application provides a battery cell 10, including a shell 1, an electrode assembly 2 and a first electrode terminal 3. The shell 1 has a first wall 13, and the first wall 13 is provided with a first lead-out hole 131. The electrode assembly 2 is accommodated in the shell 1. The first electrode terminal 3 is arranged on the first wall 13, and the first electrode terminal 3 includes a first limiter 32 and a terminal body 31 which are separately arranged and connected. The first limiter 32 is located on the side of the first wall 13 away from the electrode assembly 2. The terminal body 31 is penetrated by the first lead-out hole 131 and connected to the first limiter 32. The terminal body 31 is electrically connected to the electrode assembly 2. Among them, the minimum flow area S of the terminal body 31 is 63mm 2 -491mm 2 , the capacity C of the battery cell 10 is 500Ah-1500Ah.

[0130] The first wall 13 may be a wall of the housing 11, or may be the end cover 12. The first lead-out hole 131 is provided on the first wall 13, and penetrates the first wall 13 along the thickness direction Z of the first wall.

[0131] The first stopper 32 is located on the side of the first wall 13 away from the electrode assembly 2, so that the first stopper 32 is located outside the housing 1. The first stopper 32 is connected to the terminal body 31 to set the first electrode terminal 3 on the first wall 13. The first stopper 32 and the terminal body 31 may be riveted, welded, clamped, etc. The terminal body 31 may be directly connected to the electrode assembly 2 to achieve electrical connection between the terminal body 31 and the electrode assembly 2; or the terminal body 31 and the electrode assembly 2 may be connected through an intermediate piece, one end of the intermediate piece is connected to the terminal body 31, and the other end is connected to the electrode assembly 2; wherein the intermediate piece may be a transition piece.

[0132] The electrode assembly 2 is electrically connected to an external component through the first electrode terminal 3 to realize the input or output of electric energy of the battery cell 10. It can be that only the terminal body 31 is connected to the external component to realize the electrical connection between the electrode assembly 2 and the external component; it can also be that only the first stopper 32 is connected to the external component, and the electrode assembly 2 and the external component are connected through the terminal body 31 and the first stopper 32 to realize the electrical connection between the electrode assembly 2 and the external component; it can also be that both the terminal body 31 and the first stopper 32 are connected to the external component to realize the electrical connection between the electrode assembly 2 and the external component. Among them, the external component can be a busbar component 30.

[0133] The plane where the minimum current-carrying area of the terminal body 31 is located is perpendicular to the current-carrying path of the terminal body 31. The cross-section where the minimum current-carrying area of the terminal body 31 is located is the cross-section with the smallest area on the current-carrying path of the terminal body 31. The plane where the minimum current-carrying area of the terminal body 31 is located can be circular, polygonal, etc.

[0134] The minimum current-carrying area S of the terminal body 31 can be 63 mm 2 , 63.6 mm 2 , 70 mm 2 , 78.5 mm 2 , 80 mm 2 , 95 mm 2 , 100 mm 2 , 110 mm 2 , 113.1 mm 2 , 120 mm 2 , 132.7 mm 2 , 140 mm 2 , 153.9 mm 2 , 160 mm 2 , 176.7 mm 2 , 177 mm 2 , 180 mm 2 , 201.1 mm 2 , 210 mm 2 , 226.9 mm 2 , 240 mm 2 , 254.5 mm 2 , 270 mm 2 , 283 mm 2 , 283.5 mm 2 , 300 mm 2 , 314.2 mm 2 , 320 mm 2 , 346.4 mm 2 , 360 mm 2 , 380.1 mm 2 , 415 mm 2 , 415.5 mm 2 , 420 mm 2 , 452.4 mm 2 , 480 mm 2 , 490.9 mm 2 , 491 mm 2 Any point value among them or the point value between any two of them.

[0135] The capacitance of the battery cell 10 can be a point value of any one of 500 Ah, 530 Ah, 550 Ah, 580 Ah, 600 Ah, 630 Ah, 650 Ah, 680 Ah, 700 Ah, 730 Ah, 750 Ah, 780 Ah, 800 Ah, 830 Ah, 850 Ah, 880 Ah, 900 Ah, 930 Ah, 950 Ah, 980 Ah, 1000 Ah, 1030 Ah, 1050 Ah, 1080 Ah, 1100 Ah, 1130 Ah, 1150 Ah, 1180 Ah, 1200 Ah, 1230 Ah, 1250 Ah, 1280 Ah, 1300 Ah, 1330 Ah, 1350 Ah, 1380 Ah, 1400 Ah, 1430 Ah, 1450 Ah, 1480 Ah, 1500 Ah or a range value between any two of them.

[0136] In the embodiments of the present application, when the capacitance of the battery cell 10 is 500 Ah - 1500 Ah and the minimum current-carrying area of the terminal body 31 is greater than or equal to 63 mm 2 the terminal body 31 can have a relatively large current-carrying area, thereby improving the current-carrying capacity of the electrode terminal 3a, reducing the internal resistance of the battery cell 10, thereby reducing the energy consumption of the battery cell 10 during charging and discharging, and improving the energy conversion efficiency of the battery cell 10; when the capacitance is 500 Ah - 1500 Ah and the minimum current-carrying area of the terminal body 31 is less than or equal to 491 mm 2 it is possible to reduce the material usage of the terminal body 31 and save the manufacturing cost of the battery cell 10; therefore, when the capacitance of the battery cell 10 is 500 Ah - 1500 Ah and the minimum current-carrying area S of the terminal body 31 is 63 mm 2 - 491 mm 2 it is possible to balance reducing the material usage of the terminal body 31 and improving the current-carrying capacity of the terminal body 31, reducing the manufacturing cost of the battery cell 10 and improving the energy conversion efficiency of the battery cell 10, and improving the service performance of the battery cell 10.

[0137] In some embodiments, the capacitance C of the battery cell 10 and the minimum current-carrying area S of the terminal body 31 satisfy any one of the following conditions: (1) 500 Ah ≤ C < 800 Ah, and 63 mm 2 ≤ S ≤ 283 mm 2 ; (2) 800 Ah ≤ C < 1200 Ah, and 95 mm 2 ≤ S ≤ 415 mm 2 ; (3) 1200 Ah ≤ C ≤ 1500 Ah, and 177 mm 2 ≤ S ≤ 491 mm 2 .

[0138] When 500 Ah ≤ C < 800 Ah, the minimum overcurrent area of the terminal body 31 can be 63 mm 2 , 63.6 mm 2 , 70 mm 2 , 78.5 mm 2 , 80 mm 2 , 95 mm 2 , 100 mm 2 , 110 mm 2 , 113.1 mm 2 , 120 mm 2 , 132.7 mm 2 , 140 mm 2 , 153.9 mm 2 , 160 mm 2 , 176.7 mm 2 , 177 mm 2 , 180 mm 2 , 201.1 mm 2 , 210 mm 2 , 226.9 mm 2 , 240 mm 2 , 254.5 mm 2 , 270 mm 2 , 283 mm 2 The point value of any one of them or the point value between any two of them.

[0139] When 800 Ah ≤ C < 1200 Ah, the minimum overcurrent area of the terminal body 31 can be 95 mm 2 , 100 mm 2 , 110 mm 2 , 113.1 mm 2 , 120 mm 2 , 132.7 mm 2 , 140 mm 2 , 153.9 mm 2 , 160 mm 2 , 176.7 mm 2 , 177 mm 2 , 180 mm 2 , 201.1 mm 2 , 210 mm 2 , 226.9 mm 2 , 240 mm 2 , 254.5 mm 2 , 270 mm 2 , 283 mm 2 , 283.5 mm 2 , 300 mm 2 , 314.2 mm2 , 320 mm 2 , 346.4 mm 2 , 360 mm 2 , 380.1 mm 2 , 415 mm 2 The point value of any one of them or the point value between any two of them.

[0140] When 1200 Ah ≤ C ≤ 1500 Ah, the minimum overcurrent area of the terminal body 31 can be 177 mm 2 , 180 mm 2 , 201.1 mm 2 , 210 mm 2 , 226.9 mm 2 , 240 mm 2 , 254.5 mm 2 , 270 mm 2 , 283 mm 2 , 283.5 mm 2 , 300 mm 2 , 314.2 mm 2 , 320 mm 2 , 346.4 mm 2 , 360 mm 2 , 380.1 mm 2 , 415 mm 2 , 415.5 mm 2 , 420 mm 2 , 452.4 mm 2 , 480 mm 2 , 490.9 mm 2 , 491 mm 2 The point value of any one of them or the point value between any two of them.

[0141] In this embodiment, different ranges of the capacitance of the battery cell 10 correspond to different ranges of the minimum overcurrent area of the terminal body 31, and the larger the value range of the capacitance of the battery cell 10, the larger the value range of the minimum overcurrent area of the terminal body 31, so that the minimum overcurrent area of the terminal body 31 has better overcurrent capacity at the corresponding capacitance, which helps to reduce the internal resistance of the battery cell 10 and improve the energy conversion efficiency of the battery cell 10.

[0142] In some embodiments, the internal resistance R of the battery cell 10 is 0.03 mΩ - 0.13 mΩ.

[0143] The internal resistance of the battery cell 10 can be a point value of any one of 0.03 mΩ, 0.035 mΩ, 0.04 mΩ, 0.045 mΩ, 0.05 mΩ, 0.055 mΩ, 0.06 mΩ, 0.065 mΩ, 0.07 mΩ, 0.075 mΩ, 0.08 mΩ, 0.085 mΩ, 0.09 mΩ, 0.095 mΩ, 0.10 mΩ, 0.105 mΩ, 0.11 mΩ, 0.115 mΩ, 0.12 mΩ, 0.125 mΩ, 0.13 mΩ or a range value between any two of them.

[0144] In this embodiment, when the minimum current-carrying area of the terminal body 31 is 63 mm 2 - 491 mm 2 , when the capacitance of the battery cell 10 is 500 Ah - 1500 Ah and the internal resistance of the battery cell 10 is 0.03 mΩ - 0.13 mΩ, the battery cell 10 can have a high energy conversion efficiency, improving the performance of the battery cell 10.

[0145] In some embodiments, please refer to Figure 7 and Figure 8 , Figure 7 is an assembly schematic diagram of the first electrode terminal 3 and the first wall 13 provided in some embodiments of the present application; Figure 8 is an exploded view of the first limiting member 32 provided in some embodiments of the present application. The first limiting member 32 includes a first part 321 and a second part 322. The materials of the first part 321 and the second part 322 are different. The first part 321 is used to connect with external components. The material of the second part 322 is the same as that of the terminal body 31, and the second part 322 is welded to the terminal body 31.

[0146] The materials of the first part 321 and the second part 322 are different, and the first part 321 and the second part 322 can be connected by ultrasonic welding, friction welding, brazing, rolling composite, etc. The material of the second part 322 is the same as that of the terminal body 31, which is beneficial to the welding connection between the second part 322 and the terminal body 31, reducing the connection difficulty between the second part 322 and the terminal body 31, improving the connection strength between the second part 322 and the terminal body 31, and also improving the current-carrying capacity between the second part 322 and the terminal body 31.

[0147] In this embodiment, when current passes through the first limiting member 32 and the terminal body 31, current will pass through both the abutting portion of the first limiting member 32 and the terminal body 31 and the welded portion between the first limiting member 32 and the terminal body 31. However, the welded portion can make the connection between the first limiting member 32 and the terminal body 31 tighter, so that the current guiding ability of the welded portion is stronger than that of the abutting portion. The second portion 322 is made of the same material as the terminal body 31 to facilitate the welded connection between the terminal body 31 and the second portion 322, thereby improving the over-current capacity between the terminal body 31 and the first limiting member 32, further reducing the internal resistance of the battery cell 10, and improving the energy conversion efficiency of the battery cell 10.

[0148] In some embodiments, the first portion 321 is made of aluminum.

[0149] The second portion 322 can be made of copper, nickel, stainless steel, titanium, etc.

[0150] Aluminum has good electrical conductivity, low price, and good plasticity, which is beneficial to the production and processing of the first portion 321.

[0151] In this embodiment, the first portion 321 is made of aluminum, which can reduce the manufacturing cost of the first limiting member 32.

[0152] In some embodiments, the second portion 322 is made of copper.

[0153] The first portion 321 can be made of aluminum, nickel, stainless steel, titanium, etc.

[0154] Copper has better electrical conductivity than aluminum. Copper can enhance the electrical conductivity of the first electrode terminal 3, and both the second portion 322 and the terminal body 31 are made of copper, which is beneficial to improving the overall electrical conductivity of the first electrode terminal 3, and is also beneficial to improving the connection strength between the second portion 322 and the terminal body 31, and enhancing the connection strength between the first limiting member 32 and the terminal body 31.

[0155] In this embodiment, the second portion 322 is made of copper, which can improve the electrical conductivity of the second portion 322 and the terminal body 31 and reduce the internal resistance of the first electrode terminal 3.

[0156] In some embodiments, the first portion 321 is made of aluminum and the second portion 322 is made of copper.

[0157] In this embodiment, the first portion 321 is made of aluminum and the second portion 322 is made of copper, which can balance the improvement of the electrical conductivity of the first electrode terminal 3 and the reduction of the manufacturing cost, and improve the energy conversion efficiency of the battery cell 10.

[0158] In some embodiments, please continue to refer toFigures 7 - 9 , Figure 9 is Figure 7 An exploded view of the first electrode terminal 3 and the first wall 13 in. The first limiting member 32 is provided with a mounting hole 323. The terminal body 31 includes a first current guiding portion 311 and a second current guiding portion 312. The first current guiding portion 311 passes through the mounting hole 323 and is connected to the first limiting member 32. The second current guiding portion 312 passes through the first lead-out hole 131. The first current guiding portion 311 protrudes from one end of the second current guiding portion 312 facing away from the electrode assembly 2. The position with the smallest current-carrying area of the terminal body 31 is located at the first current guiding portion 311.

[0159] It can be that all of the first current guiding portion 311 is located within the mounting hole 323; it can also be that only a part of the first current guiding portion 311 is located within the mounting hole 323. It can be that the part of the first current guiding portion 311 located within the mounting hole 323 is connected to the hole wall surface of the mounting hole 323 to realize the connection between the first current guiding portion 311 and the first limiting member 32.

[0160] It can be that all of the second current guiding portion 312 is located within the first lead-out hole 131; it can also be that only a part of the second current guiding portion 312 is located within the first lead-out hole 131. The first current guiding portion 311 protrudes from one end of the second current guiding portion 312 facing away from the electrode assembly 2, so that the smallest current-carrying area of the first current guiding portion 311 is smaller than the current-carrying area of the second current guiding portion 312.

[0161] The first current guiding portion 311 is connected to the first limiting member 32. When the battery cell 10 discharges, the current can be conducted to the external component after passing through the second current guiding portion 312, the first current guiding portion 311 and the first limiting member 32 in sequence. The position with the smallest current-carrying area of the terminal body 31 is the first current guiding portion 311 within the mounting hole 323.

[0162] In this embodiment, by setting the position with the smallest current-carrying area of the terminal body 31 at the first current guiding portion 311, the smallest current-carrying area of the first current guiding portion 311 is 63 mm 2 -491 mm 2 , so that the first current guiding portion 311 has a strong current-carrying capacity, thereby reducing the current-carrying internal resistance of the first electrode terminal 3, and further reducing the internal resistance of the battery cell 10 and improving the energy conversion efficiency of the battery cell 10.

[0163] In some embodiments, the mounting hole 323 can be provided in the second part 322; it can also be that a part of the mounting hole 323 is provided in the second part 322 and the other part is provided in the first part 321. The mounting hole 323 penetrates through the first limiting member 32 along the thickness direction Z of the first wall.

[0164] In some embodiments, please continue to refer to Figure 7 and Figure 10, Figure 10 is Figure 7 a partial enlarged view of region B in [description of the overall figure or context]. The second diversion portion 312 has a first abutting surface 3121, the first diversion portion 311 protrudes from the first abutting surface 3121, the first diversion portion 311 has a second abutting surface 3111 facing the first abutting surface 3121, and the first abutting surface 3121 and the second abutting surface 3111 cooperate to clamp a part of the first limiting member 32 to restrict the movement of the first limiting member 32 relative to the terminal body 31 along the thickness direction Z of the first wall.

[0165] The second abutting surface 3111 faces the first abutting surface 3121 so that the first abutting surface 3121 and the second abutting surface 3111 are disposed opposite to each other along the thickness direction Z of the first wall. The first abutting surface 3121 and the second abutting surface 3111 cooperate to clamp a part of the first limiting member 32 so that a part of the first limiting member 32 extends between the first abutting surface 3121 and the second abutting surface 3111, thereby making the minimum flow-through area of the part of the first diversion portion 311 located between the first abutting surface 3121 and the second abutting surface 3111 smaller than the flow-through area of the second diversion portion 312 and smaller than the flow-through area of the part of the first diversion portion 311 where the first abutting surface 3121 faces away from the second abutting surface 3111.

[0166] In this embodiment, the first diversion portion 311 and the second diversion portion 312 cooperate to clamp a part of the first limiting member 32 to achieve the connection between the terminal body 31 and the first limiting member 32, reducing the risk of the first limiting member 32 detaching from the terminal body 31 and improving the structural stability of the first electrode terminal 3.

[0167] In some embodiments, please continue to refer to Figures 7 - 10 . The first diversion portion 311 includes a first diversion section 3112 and a second diversion section 3113. The first diversion section 3112 protrudes from the first abutting surface 3121. The first diversion section 3112 connects the second diversion section 3113 and the second diversion portion 312. One end of the second diversion section 3113 close to the first diversion section 3112 forms the second abutting surface 3111. The diameter of the first diversion section 3112 is smaller than the diameter of the second diversion section 3113. The position with the smallest flow-through area of the terminal body 31 is located at the first diversion section 3112.

[0168] In the projection plane perpendicular to the first wall 13, the first diversion section 3112 protrudes from the first abutting surface 3121 so that the minimum projected area of the first diversion section 3112 is smaller than the projected area of the part surrounded by the outer edge of the first abutting surface 3121. One end of the second diversion section 3113 close to the first diversion section 3112 forms the second abutting surface 3111 so that the minimum projected area of the first diversion section 3112 is smaller than the projected area of the part surrounded by the outer edge of the second abutting surface 3111.

[0169] The cross-sectional area of ​​the terminal body 31 along the thickness direction Z of the first wall is smaller than the second guide section 3113 and the second guide portion 312 , so that the position where the flow area of ​​the terminal body 31 is the smallest is located in the first guide section 3112 .

[0170] The first guide section 3112 is located between the first abutting surface 3121 and the second abutting surface 3111. The cross sections of the first guide section 3112 and the second guide section 3113 along the thickness direction Z of the first wall are both circular.

[0171] In this embodiment, a portion of the first limiter 32 extends between the first abutment surface 3121 of the second guide portion 312 and the second abutment surface 3111 of the second guide section 3113, so as to be arranged close to the first guide section 3112, so that the second guide section 3113 and the second guide portion 312 cooperate to clamp a portion of the first limiter 32, so that the connection between the first limiter 32 and the terminal body 31 is more stable; the minimum flow area of ​​the first guide section 3112 is the minimum flow area of ​​the terminal body 31, and the minimum flow area of ​​the first guide section 3112 is 63mm 2 -491mm 2 , so that the terminal body 31 has a higher current carrying capacity, reduces the internal resistance of the battery cell 10, and improves the energy conversion efficiency of the battery cell 10.

[0172] In some embodiments, the terminal body 31 is riveted to the first stopper 32 , and one end of the terminal body 31 away from the electrode assembly 2 is riveted toward the electrode terminal 3 a to form a first guide section 3112 .

[0173] In some embodiments, please refer to Figure 10 The difference between the diameter of the second flow guiding section 3113 and the diameter of the first flow guiding section 3112 is D1 ( Figure 10 Not shown), 1mm≤D1≤10mm.

[0174] The difference D1 between the diameters of the first guide section 3112 and the second guide section 3113 is twice the difference R1 between their radii. Figure 10 The difference R1 between the radius of the first guide section 3112 and the radius of the second guide section 3113 is shown in FIG.

[0175] The diameter of the second guide section 3113 is greater than the diameter of the first guide section 3112. D1 can be any point value among 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9mm, 9.5mm, 10mm or any point value between any two.

[0176] In this embodiment, when D1 ≥ 1 mm, the second abutting surface 3111 of the second diversion section 3113 can have a larger area in contact with the first limiting member 32, thereby enhancing the limiting effect of the first abutting surface 3121 and the second abutting surface 3111 on the first limiting member 32 and improving the connection stability between the first limiting member 32 and the terminal body 31; when D1 ≤ 10 mm, the material usage of the second diversion section 3113 can be reduced, the installation difficulty between the terminal body 31 and the first limiting member 32 can be lowered, and the setting cost of the second diversion section 3113 can be reduced; therefore, when 1 mm ≤ D1 ≤ 10 mm, it is possible to balance the improvement of the connection stability between the first limiting member 32 and the terminal body 31 and the reduction of the setting cost of the second diversion section 3113.

[0177] In some embodiments, please continue to refer to Figures 7 - 11 , Figure 11 which is Figure 9 a partial enlarged view of region C in . The first limiting member 32 includes a first portion 321 and a second portion 322. The materials of the first portion 321 and the second portion 322 are different. The first portion 321 is used for connecting with an external component, and the second portion 322 has the same material as the terminal body 31; the mounting hole 323 includes a first hole section 3231 located in the first portion 321 and a second hole section 3232 located in the second portion 322. The first hole section 3231 is closer to the electrode assembly 2 than the second hole section 3232. The portion of the first diversion section 311 located in the second hole section 3232 is welded to the second portion 322.

[0178] The portion of the first diversion section 311 located in the second hole section 3232 is welded to the second portion 322. In the embodiment where the first diversion section 311 includes the second hole section 3232, it can be that the entire second diversion section 3113 is located in the second hole section 3232; or it can be that only a part of the second diversion section 3113 is located in the second hole section 3232. The second diversion section 3113 is welded to the second portion 322 to improve the diversion ability of the second diversion section 3113 and the second portion 322, so that when current flows between the first electrode terminal 3 and the first limiting member 32, for example, when the battery cell 10 discharges, the current mainly flows through the second diversion portion 312, through the first diversion section 3112 to the second diversion section 3113, and then flows from the second diversion section 3113 to the second portion 322; in such a diversion path, the cross-sectional area of the first diversion section 3112 directly affects the current-carrying capacity of the entire current-carrying path. Therefore, when the cross-sectional area S of the first diversion section 3112 is 63 mm 2 -491 mm 2 , it is possible to improve the current-carrying capacity of the first electrode terminal 3, reduce the internal resistance of the battery cell 10, thereby enhancing the energy conversion efficiency of the battery cell 10 and improving the performance of the battery cell 10.

[0179] In this embodiment, by arranging that the part of the first diversion part 311 located in the second hole section 3232 is welded to the second part 322, on the one hand, the connection strength between the first diversion part 311 and the first limiting part 32 can be enhanced; on the other hand, the welded connection between the first diversion part 311 and the second part 322 can improve the diversion ability of the first diversion part 311 and the second part 322, thereby improving the diversion ability of the first electrode terminal 3, reducing the internal resistance of the first electrode terminal 3, thereby reducing the internal resistance of the battery cell 10, and improving the energy conversion efficiency of the battery cell 10.

[0180] In some embodiments, please refer to FIG. Figure 11 and 12 , Figure 12 is Figure 4 a partial enlarged view of region E in. The minimum distance between the outer peripheral surface of the second part 322 and the hole wall surface of the second hole section 3232 is D2, and 1 mm ≤ D2 ≤ 10 mm.

[0181] D2 can be any point value among 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm, 8.5 mm, 9 mm, 9.5 mm, 10 mm or any point value between any two of them.

[0182] In this embodiment, when D2 ≥ 1 mm, the second part 322 can have a larger size, so as to facilitate the welding of the second part 322 and the first diversion part 311, and also facilitate improving the contact area between the second part 322 and the first part 321, and improving the diversion ability of the first limiting part 32; when D2 ≤ 10 mm, the material usage of the second part 322 can be reduced, and the setting cost of the second part 322 can be saved; therefore, when 1 mm ≤ D2 ≤ 10 mm, it is possible to balance improving the diversion ability of the first limiting part 32 and reducing the setting cost of the second part 322.

[0183] In some embodiments, please continue to refer to Figure 12 . Along the first direction X, the minimum width of the second part 322 is 14 mm - 30 mm, and the first direction X is perpendicular to the thickness direction Z of the first wall.

[0184] The first direction X is perpendicular to the thickness direction Z of the first wall. There may be two electrode terminals 3a provided on the first wall 13. The two electrode terminals 3a include a first electrode terminal 3. The two electrode terminals 3a are arranged along the first direction X. The first direction X is the direction where the minimum width of the second part 322 is located. The minimum width of the second part 322 is the minimum width of the second part 322 along the first direction X. The second part 322 may be square, diamond-shaped, oval, circular, etc. In the embodiment where the second part 322 is circular, the minimum width of the second part 322 refers to the diameter of the second part 322.

[0185] The minimum width of the second part 322 is a point value of any one of 14mm, 14.5mm, 15mm, 15.5mm, 16mm, 16.5mm, 17mm, 17.5mm, 18mm, 18.5mm, 19mm, 19.5mm, 20mm, 20.5mm, 21mm, 21.5mm, 22mm, 22.5mm, 23mm, 23.5mm, 24mm, 24.5mm, 25mm, 25.5mm, 26mm, 26.5mm, 27mm, 27.5mm, 28mm, 28.5mm, 29mm, 29.5mm, 30mm or a point value between any two of them.

[0186] In this embodiment, when the minimum width of the second part 322 is greater than or equal to 14mm, the contact area between the second part 322 and the first part 321 can be increased, and the current guiding ability between the first part 321 and the second part 322 can be improved; when the minimum width of the second part 322 is less than or equal to 30mm, the material usage of the second part 322 can be reduced, and the setting cost of the second part 322 can be saved. Therefore, when the minimum width of the second part 322 is 14mm - 30mm, it is possible to balance the improvement of the current guiding ability between the first part 321 and the second part 322 and the saving of the setting cost of the second part 322.

[0187] In some embodiments, please refer to Figure 4 and Figure 13 , Figure 13 is a schematic structural diagram of the first electrode terminal 3 provided in some embodiments of the present application. The battery cell 10 further includes a second electrode terminal 3b (shown in Figure 4 ) having a polarity opposite to that of the first electrode terminal 3. The second electrode terminal 3b is provided on the first wall 13 and is spaced apart from the first electrode terminal 3 along the first direction X. The first direction X is perpendicular to the thickness direction Z of the first wall. The first part 321 has a first surface 3212 facing away from the electrode assembly 2. The first surface 3212 is located on the side of the second part 322 facing away from the second electrode terminal 3b. Along the first direction X, the width of the first surface 3212 is 10mm - 100mm.

[0188] The first surface 3212 is located on the side of the second part 322 facing away from the second electrode terminal 3b, so as to facilitate the electrical connection between the first surface 3212 and an external component.

[0189] The width of the first surface 3212 is D3, and D3 can be any value among 10mm, 12mm, 15mm, 17mm, 20mm, 22mm, 25mm, 27mm, 30mm, 32mm, 35mm, 37mm, 40mm, 42mm, 45mm, 47mm, 50mm, 52mm, 55mm, 57mm, 60mm, 62mm, 65mm, 67mm, 70mm, 72mm, 75mm, 77mm, 80mm, 82mm, 85mm, 87mm, 90mm, 92mm, 95mm, 97mm, 100mm or any value between any two of them.

[0190] In this embodiment, when the width of the first surface 3212 is greater than or equal to 10mm, the first part 321 has sufficient dimensions to contact an external component, facilitating the input or output of electrical energy of the battery cell 10 through the external component and reducing the difficulty of setting the battery cell 10; when the width of the first surface 3212 is less than or equal to 100mm, the material usage of the first part 321 can be reduced, saving the setting cost of the first part 321; therefore, when the width of the first surface 3212 is 10mm - 100mm, it is possible to balance reducing the difficulty of setting the battery cell 10 and saving the setting cost of the first part 321.

[0191] In some embodiments, please refer to Figure 14 , Figure 14 is Figure 8 a partial enlarged view of the F region in

[0192] One end of the first hole section 3231 away from the electrode assembly 2 extends to the bottom surface of the accommodating groove 3211, and at least a part of the second part 322 is accommodated in the accommodating groove 3211.

[0193] In this embodiment, the first hole section 3231 communicates with the accommodation groove 3211, so that the first diversion part 311 can pass through the first hole section 3231 and extend into the accommodation groove 3211 to connect with the second part 322, reducing the difficulty of arranging the first diversion part 311. At least part of the second part 322 is accommodated in the accommodation groove 3211, which can increase the contact area between the second part 322 and the groove wall surface of the accommodation groove 3211, thereby increasing the diversion area between the second part 322 and the first part 321 and enhancing the diversion capacity of the first part 321 and the second part 322.

[0194] In some embodiments, in the projection plane perpendicular to the thickness direction Z of the first wall, the sum of the projected areas of the orthographic projection of the second part 322 and the orthographic projection of the first diversion part 311 is less than or equal to the projected area of the orthographic projection of the second diversion part 312.

[0195] In the projection plane perpendicular to the thickness direction Z of the first wall, it may be that the orthographic projection of the second part 322 does not overlap with the orthographic projection of the first diversion part 311, and the sum of the projected areas of the orthographic projection of the second part 322 and the orthographic projection of the first diversion part 311 is the area of the orthographic projection of the second part 322 plus the area of the orthographic projection of the first diversion part 311.

[0196] In this embodiment, the second diversion part 312 can have a larger flow-through area, reducing the influence of the second diversion part 312 on the current-carrying capacity of the first electrode terminal 3.

[0197] In some embodiments, please refer to Figure 15 , Figure 15 is a schematic structural diagram of the terminal body 31 provided in some embodiments of the present application. The terminal body 31 further includes a third diversion part 313. The third diversion part 313 is located on the side of the first wall 13 facing the electrode assembly 2. The second diversion part 312 connects the third diversion part 313 and the first diversion part 311, and the third diversion part 313 and the first limiting part 32 cooperate to clamp the first wall 13.

[0198] The first limiting part 32 is connected to the first diversion part 311, so that the third diversion part 313 and the first limiting part 32 are indirectly connected. A part of the first wall 13 is located between the third diversion part 313 and the first limiting part 32, so that the third diversion part 313 and the first limiting part 32 cooperate to clamp the first wall 13.

[0199] In this embodiment, the third diversion part 313 and the first limiting part 32 cooperate to clamp the first wall 13, improving the connection stability between the first electrode terminal 3 and the first wall 13.

[0200] In some embodiments, the first diversion part 311, the second diversion part 312 and the third diversion part 313 are integrally formed.

[0201] In this embodiment, the first diversion part 311, the second diversion part 312, and the third diversion part 313 are integrally formed, which reduces the difficulty of arranging the first diversion part 311, the second diversion part 312, and the third diversion part 313 and reduces the arrangement cost of the first diversion part 311, the second diversion part 312, and the third diversion part 313.

[0202] In some embodiments, the first diversion part 311, the second diversion part 312, and the third diversion part 313 are separately arranged and connected; for example, the second diversion part 312 is respectively welded to the first diversion part 311 and the third diversion part 313.

[0203] In some embodiments, the ratio of the capacitance C of the battery cell 10 to the minimum overcurrent area S of the terminal body 31 is 2 Ah / mm 2 -7 Ah / mm 2 .

[0204] The ratio of the capacitance C of the battery cell 10 to the minimum overcurrent area S of the terminal body 31 can be 2 Ah / mm 2 , 2.1 Ah / mm 2 , 2.2 Ah / mm 2 , 2.3 Ah / mm 2 , 2.4 Ah / mm 2 , 2.5 Ah / mm 2 , 2.6 Ah / mm 2 , 2.7 Ah / mm 2 , 2.8 Ah / mm 2 , 2.9 Ah / mm 2 , 3 Ah / mm 2 , 3.1 Ah / mm 2 , 3.2 Ah / mm 2 , 3.3 Ah / mm 2 , 3.4 Ah / mm 2 , 3.5 Ah / mm 2 , 3.6 Ah / mm 2 , 3.7 Ah / mm 2 , 3.8 Ah / mm 2 , 3.9 Ah / mm 2 , 4 Ah / mm 2 , 4.1 Ah / mm 2 , 4.2 Ah / mm 2 , 4.3 Ah / mm 2 , 4.4 Ah / mm 2 , 4.5 Ah / mm 2 , 4.6 Ah / mm 2 , 4.7 Ah / mm 2, 4.8 Ah / mm 2 , 4.9 Ah / mm 2 , 5 Ah / mm 2 , 5.1 Ah / mm 2 , 5.2 Ah / mm 2 , 5.3 Ah / mm 2 , 5.4 Ah / mm 2 , 5.5 Ah / mm 2 , 5.6 Ah / mm 2 , 5.7 Ah / mm 2 , 5.8 Ah / mm 2 , 5.9 Ah / mm 2 , 6 Ah / mm 2 , 6.1 Ah / mm 2 , 6.2 Ah / mm 2 , 6.3 Ah / mm 2 , 6.4 Ah / mm 2 , 6.5 Ah / mm 2 , 6.6 Ah / mm 2 , 6.7 Ah / mm 2 , 6.8 Ah / mm 2 , 6.9 Ah / mm 2 , 7 Ah / mm 2 The point value of any one of them or the point value between any two of them.

[0205] In this embodiment, the battery cell 10 corresponding to the capacitance can have a relatively large minimum over-current area of the terminal body 31, thereby improving the over-current capacity of the first electrode terminal 3, reducing the internal resistance of the battery cell 10, and improving the energy conversion efficiency of the battery cell 10.

[0206] In some embodiments, please refer to Figure 16 , Figure 16 is an assembly schematic diagram of the electrode terminal 3a and the first wall 13 provided in some embodiments of the present application. The battery cell 10 further includes a second electrode terminal 3b with a polarity opposite to that of the first electrode terminal 3. The first wall 13 is provided with a second lead-out hole 132. The second lead-out hole 132 and the first lead-out hole 131 are spaced apart along the first direction X. The second electrode terminal 3b passes through the second lead-out hole 132. The first direction X is perpendicular to the thickness direction Z of the first wall; along the first direction X, the ratio of the center distance between the second lead-out hole 132 and the first lead-out hole 131 to the size of the electrode assembly 2 is 0.2 - 0.75.

[0207] The first lead hole 131 and the second lead hole 132 may be arranged at intervals. The center distance between the first lead hole 131 and the first lead hole 131 is D4, and the dimension of the electrode assembly 2 in the first direction X is D5. The ratio of D4 to D5 may be any point value among 0.35, 0.38, 0.41, 0.44, 0.47, 0.5, 0.53, 0.56, 0.59, 0.62, 0.65, 0.68, 0.71, 0.74, 0.75, 0.76, 0.77, 0.78, 0.8 or a point value between any two of them.

[0208] In this embodiment, the distance between the first electrode terminal 3 and the second electrode terminal 3b is relatively close, so that the internal resistance between the first electrode terminal 3 and the second electrode terminal 3b can be reduced, and the energy conversion efficiency of the battery cell 10 can be improved.

[0209] In some embodiments, the terminal body 31 is welded to the tab 21.

[0210] In some embodiments, please refer to Figure 17 , Figure 17 is an assembly schematic diagram of the terminal body 31 and the electrode assembly 2 provided in some embodiments of the present application. The battery cell 10 further includes a connecting member 4. The electrode assembly 2 is provided with a tab 21. At least a part of the connecting member 4 is located between the tab 21 and the terminal body 31. The tab 21, the connecting member 4 and the terminal body 31 are welded to form a first connecting portion 41, and the first connecting portion 41 connects the connecting member 4, the tab 21 and the terminal body 31.

[0211] The first connecting portion 41 may be a weld mark formed by welding the tab 21, the connecting member 4 and the terminal body 31, and the tab 21, the connecting member 4 and the terminal body 31 are all connected to the first connecting portion 41.

[0212] In this embodiment, the connection between the tab 21 and the terminal body 31 is more stable, and the connection stability between the tab 21 and the terminal body 31 is improved.

[0213] In some embodiments, the cross-section of the minimum current-carrying area S of the terminal body 31 is a circular surface, the diameter of the circular surface is 9 mm - 25 mm, and the cross-section is perpendicular to the thickness direction of the first wall.

[0214] The diameter of the cross-section where the minimum current-carrying area of the terminal body 31 is located can be any point value among 9mm, 9.5mm, 10mm, 10.5mm, 11mm, 11.5mm, 12mm, 12.5mm, 13mm, 13.5mm, 14mm, 14.5mm, 15mm, 15.5mm, 16mm, 16.5mm, 17mm, 17.5mm, 18mm, 18.5mm, 19mm, 19.5mm, 20mm, 20.5mm, 21mm, 21.5mm, 22mm, 22.5mm, 23mm, 23.5mm, 24mm, 24.5mm, 25mm or any point value between any two of them.

[0215] In this embodiment, when the diameter of the circular surface is greater than or equal to 9mm, the first electrode terminal 3 can have a relatively large current-carrying area, reducing the internal resistance of the battery cell 10 and improving the energy conversion efficiency of the battery cell 10; when the diameter of the circular surface is less than or equal to 25mm, the setting cost of the terminal body 31 can be saved; therefore, when the diameter of the circular surface is 9mm - 25mm, the improvement of the energy conversion efficiency of the battery cell 10 and the saving of the setting cost of the terminal body 31 can be taken into account.

[0216] The embodiment of the present application provides a battery device 100, including the battery cell 10 provided in any one of the above embodiments.

[0217] In some embodiments, please refer to Figure 18 , Figure 18 is an assembly schematic diagram of the battery cell 10 and the busbar component 30 provided in some embodiments of the present application. The battery device 100 includes a busbar component 30 and a plurality of battery cells 10. The busbar component 30 is electrically connected to the plurality of battery cells 10, and the first limiting member 32 of the first electrode terminal 3 of at least one battery cell 10 is connected to the busbar component 30. And in the projection plane perpendicular to the thickness direction Z of the first wall, the area of the overlapping part of the orthographic projection of the first limiting member 32 and the orthographic projection of the busbar component 30 connected to the first limiting member 32 is 300mm 2 - 3000mm 2 .

[0218] The plurality of battery cells 10 are arranged along the second direction Y, and the second direction Y, the first direction X and the thickness direction Z of the first wall are perpendicular to each other in pairs.

[0219] The battery cell 10 includes two electrode terminals 3a with opposite polarities, and the two electrode terminals 3a are arranged at intervals along the first direction X. The two electrode terminals 3a include the first electrode terminal 3.

[0220] The busbar component 30 can be connected to the electrode terminals 3a of only two battery cells 10 arranged along the second direction Y, or can be connected to the electrode terminals 3a of three or more battery cells 10 arranged along the second direction Y.

[0221] It can be that the busbar component 30 is connected to the electrode terminals 3a of two battery cells 10, and the polarities of the two electrode terminals 3a are opposite so that the two battery cells 10 are connected in series; or the polarities of the two electrode terminals 3a are the same so that the two battery cells 10 are connected in parallel.

[0222] The area of the overlapping part of the orthographic projection of the first limiting member 32 and the orthographic projection of the busbar component 30 connected to the first limiting member 32 can be 300 mm 2 、400 mm 2 、500 mm 2 、600 mm 2 、700 mm 2 、800 mm 2 、900 mm 2 、1000 mm 2 、1100 mm 2 、1200 mm 2 、1300 mm 2 、1400 mm 2 、1500 mm 2 、1600 mm 2 、1700 mm 2 、1800 mm 2 、1900 mm 2 、2000 mm 2 、2100 mm 2 、2200 mm 2 、2300 mm 2 、2400 mm 2 、2500 mm 2 、2600 mm 2 、2700 mm 2 、2800 mm 2 、2900 mm 2 、3000 mm 2 Any value among them or any value between any two of them.

[0223] In this embodiment, the busbar component 30 and the first limiting member 32 can have a large contact area, thereby improving the current guiding ability of the busbar component 30 and the first limiting member 32 and facilitating the input or output of electric energy of the battery cell 10.

[0224] An embodiment of the present application provides an energy storage device, including the battery cell 10 provided in any one of the above embodiments or the battery device 100 provided in any one of the above embodiments.

[0225] An embodiment of the present application provides an energy storage system, including a power conversion device and the energy storage device provided in any one of the above embodiments. The power conversion device is used to electrically connect a power generation device and the energy storage device.

[0226] An embodiment of the present application provides a charging network, including a charging pile and the energy storage device provided in any one of the above embodiments. The energy storage device is used to provide electric energy for the charging pile.

[0227] An embodiment of the present application provides an electrical device, including the battery cell 10 provided in any one of the above embodiments or the battery device 100 provided in any one of the above embodiments. The battery cell 10 is used to provide electric energy for the electrical device.

[0228] Please continue to refer to Figures 4 - 13 , an embodiment of the present application provides a battery cell 10, including a housing 1, an electrode assembly 2, and a first electrode terminal 3. The housing 1 has a first wall 13, and the first wall 13 is provided with a first lead-out hole 131. The electrode assembly 2 is accommodated in the housing 1. The first electrode terminal 3 is disposed on the first wall 13. The first electrode terminal 3 includes a first limiting member 32 and a terminal body 31 that are separately arranged and connected. The first limiting member 32 is located on the side of the first wall 13 away from the electrode assembly 2. The terminal body 31 passes through the first lead-out hole 131 and is connected to the first limiting member 32. The terminal body 31 is electrically connected to the electrode assembly 2. Wherein, the minimum current-carrying area S of the terminal body 31 is 63 mm 2 -491 mm 2, the capacity C of the battery cell 10 is 500Ah-1500Ah. The first stopper 32 is provided with a mounting hole 323, and the terminal body 31 includes a first guide portion 311 and a second guide portion 312. The first guide portion 311 is inserted into the mounting hole 323 and connected to the first stopper 32, and the second guide portion 312 is inserted into the first lead-out hole 131. The first guide portion 311 is protruded from the end of the second guide portion 312 away from the electrode assembly 2. The first guide portion 311 includes a first guide section 3112 and a second guide section 3113. The first guide section 3112 is protruded from the first abutment surface 3121. The first guide section 3112 connects the second guide section 3113 and the second guide portion 312. The second guide section 3113 is close to one end of the first guide section 3112 to form a second abutment surface 3111. The diameter of the first guide section 3112 is smaller than the diameter of the second guide section 3113. The position where the flow area of ​​the terminal body 31 is the smallest is located in the first guide section 3112. The first limiting member 32 includes a first part 321 and a second part 322, the first part 321 and the second part 322 are made of different materials, the first part 321 is used to connect with external components, and the second part 322 is made of the same material as the terminal body 31; the mounting hole 323 includes a first hole section 3231 located in the first part 321 and a second hole section 3232 located in the second part 322, the first hole section 3231 is closer to the electrode assembly 2 than the second hole section 3232, and the part of the first guide portion 311 located in the second hole section 3232 is welded to the second part 322.

[0229] In such a battery cell 10, when the capacity of the battery cell 10 is 500Ah-1500Ah and the minimum flow area of ​​the terminal body 31 is greater than or equal to 63mm 2 When the capacity is 500Ah-1500Ah and the minimum flow area of ​​the terminal body 31 is less than or equal to 491mm, the terminal body 31 can have a larger flow area, thereby improving the flow capacity of the electrode terminal 3a, reducing the internal resistance of the battery cell 10, thereby reducing the energy consumption of the battery cell 10 during charging and discharging, and improving the energy conversion efficiency of the battery cell 10; when the capacity is 500Ah-1500Ah and the minimum flow area of ​​the terminal body 31 is less than or equal to 491mm 2 When the material usage of the terminal body 31 is reduced, the manufacturing cost of the battery cell 10 can be saved; therefore, when the capacity of the battery cell 10 is 500Ah-1500Ah and the minimum flow area S of the terminal body 31 is 63mm 2 -491mm 2When it is possible to balance the reduction of the material usage of the terminal body 31 and the improvement of the over-current capacity of the terminal body 31, the manufacturing cost of the battery cell 10 is reduced, the energy conversion efficiency of the battery cell 10 is improved, and the service performance of the battery cell 10 is enhanced. A part of the first limiting member 32 extends between the first abutting surface 3121 of the second diversion portion 312 and the second abutting surface 3111 of the second diversion section 3113, and is arranged to lean towards the first diversion section 3112, so that the second diversion section 3113 and the second diversion portion 312 cooperate to clamp a part of the first limiting member 32, making the connection between the first limiting member 32 and the terminal body 31 more stable; the minimum over-current area of the first diversion section 3112 is the minimum over-current area of the terminal body 31, and the minimum over-current area of the first diversion section 3112 is 63mm 2 -491mm 2 , so that the terminal body 31 has a high over-current capacity, reduces the internal resistance of the battery cell 10, and improves the energy conversion efficiency of the battery cell 10. By arranging that the part of the first diversion portion 311 located in the second hole section 3232 is welded to the second part 322, on the one hand, the connection strength between the first diversion portion 311 and the first limiting member 32 can be enhanced; on the other hand, the welding connection between the first diversion portion 311 and the second part 322 can improve the diversion capacity of the first diversion portion 311 and the second part 322, thereby improving the diversion capacity of the first electrode terminal 3, reducing the internal resistance of the first electrode terminal 3, thereby reducing the internal resistance of the battery cell 10, and improving the energy conversion efficiency of the battery cell 10.

[0230] Example 1

[0231] The battery cell 10 using the LFP system is used for experiments. The battery cell 10 includes a housing 1, an electrode assembly 2 and a first electrode terminal 3. The electrode assembly 2 is accommodated in the housing 1. The housing 1 includes a housing body 11 and an end cover 12, the end cover 12 is covered on the housing body 11, and a first lead-out hole 131 is provided on the end cover 12. The first electrode terminal 3 includes a terminal body 31 and a first limiting member 32, and the terminal body 31 passes through the first lead-out hole 131 and is riveted to the first limiting member 32. The terminal body 31 includes a second diversion section 3113, a first diversion section 3112, a second diversion portion 312 and a third diversion portion 313 connected in sequence. The second diversion section 3113 and the second diversion portion 312 cooperate to clamp the first limiting member 32, and the first limiting member 32 and the third diversion portion 313 cooperate to clamp the end cover 12. The first limiting member 32 includes a first part 321 made of aluminum and a second part 322 made of copper, and the second diversion section 3113 is welded to the second part 322. The position with the smallest over-current area of the terminal body 31 is located in the first diversion section 3112.

[0232] Among them, the minimum over-current area S of the terminal body 31 is 63mm 2 , and the capacitance C of the battery cell 10 is 500Ah.

[0233] Example 2

[0234] It is basically the same as Example 1, except that the minimum current-carrying area S of the terminal body 31 is 177 mm 2 .

[0235] Example 3

[0236] It is basically the same as Example 1, except that the minimum current-carrying area S of the terminal body 31 is 283 mm 2 .

[0237] Example 4

[0238] It is basically the same as Example 1, except that the minimum current-carrying area S of the terminal body 31 is 491 mm 2 .

[0239] Example 5

[0240] It is basically the same as Example 1, except that the capacitance C of the battery cell 10 is 800 Ah.

[0241] Example 6

[0242] It is basically the same as Example 5, except that the minimum current-carrying area S of the terminal body 31 is 95 mm 2 .

[0243] Example 7

[0244] It is basically the same as Example 5, except that the minimum current-carrying area S of the terminal body 31 is 177 mm 2 .

[0245] Example 8

[0246] It is basically the same as Example 5, except that the minimum current-carrying area S of the terminal body 31 is 183 mm 2 .

[0247] Example 9

[0248] It is basically the same as Example 5, except that the minimum current-carrying area S of the terminal body 31 is 415 mm 2 .

[0249] Example 10

[0250] It is basically the same as Example 5, except that the minimum current-carrying area S of the terminal body 31 is 491 mm 2 .

[0251] Example 11

[0252] It is basically the same as Example 1, except that the capacitance C of the battery cell 10 is 1200 Ah.

[0253] Example 12

[0254] It is basically the same as Example 11, except that the minimum current-carrying area S of the terminal body 31 is 95 mm 2 .

[0255] Example 13

[0256] It is basically the same as Example 11, except that the minimum current-carrying area S of the terminal body 31 is 177 mm 2 .

[0257] Example 14

[0258] It is basically the same as Example 11, except that the minimum current-carrying area S of the terminal body 31 is 283 mm 2 .

[0259] Example 15

[0260] It is basically the same as Example 11, except that the minimum current-carrying area S of the terminal body 31 is 415 mm 2 .

[0261] Example 16

[0262] It is basically the same as Example 11, except that the minimum current-carrying area S of the terminal body 31 is 491 mm 2 .

[0263] Example 17

[0264] It is basically the same as Example 1, except that the capacitance C of the battery cell 10 is 1500 Ah.

[0265] Example 18

[0266] It is basically the same as Example 17, except that the minimum current-carrying area S of the terminal body 31 is 95 mm 2 .

[0267] Example 19

[0268] It is basically the same as Example 17, except that the minimum current-carrying area S of the terminal body 31 is 177 mm 2 .

[0269] Example 20

[0270] It is basically the same as Example 17, except that the minimum current-carrying area S of the terminal body 31 is 283 mm 2 .

[0271] Example 21

[0272] It is basically the same as Example 17, except that the minimum current-carrying area S of the terminal body 31 is 415 mm 2 .

[0273] Example 22

[0274] It is basically the same as Example 17, except that the minimum current-carrying area S of the terminal body 31 is 491 mm 2 .

[0275] Comparative Example 1

[0276] It is basically the same as Example 1, except that the minimum current-carrying area S of the terminal body 31 is 38.5 mm 2 , and the capacitance C of the battery cell 10 is 1800 Ah.

[0277] The battery cells 10 in Comparative Example 1 and Examples 1-22 were respectively tested according to the following steps:

[0278] Among them, the minimum current-carrying area of the battery cell 10 can be obtained by testing according to the following method:

[0279] The first wall 13 provided with the first electrode terminal 3 was coated with hydrogel and embedded with epoxy resin. After fixing, it was polished to the cross-section where the axis of the terminal body is located. The cross-section was polished to a mirror surface. It was photographed through a metallographic microscope, and the value at the position with the smallest diameter of the terminal body 31 was measured, and the area at this place was calculated as the minimum current-carrying area of the terminal body 31.

[0280] The capacity of the battery cell 10 can be obtained by testing according to the following method:

[0281] At 25 °C, the battery cell was left standing for 5 min, and discharged at a constant current of 0.33C to the lower cut-off voltage: after standing for 5 min, it was charged at a constant current of 0.33C to the upper cut-off voltage, and then charged at a constant voltage at the upper cut-off voltage until the current was 0.05C: after standing for 5 min, it was discharged at a constant current of 0.33C to the lower cut-off voltage, and the discharge capacity at this time was recorded as the capacity of the battery cell. The upper cut-off voltage and the lower cut-off voltage can adopt the charge and discharge voltages recommended in the product specification of the battery cell. For example, when the positive electrode active material includes lithium iron phosphate and the negative electrode active material includes graphite, the upper cut-off voltage of the battery cell can be 3.65 V and the lower cut-off voltage can be 2.5 V.

[0282] The energy conversion efficiency value of the battery cell 10 can be obtained by testing according to the following method:

[0283] Under the 25°C initial charge and discharge performance test standard in GBT 36276-2023 Lithium-ion Batteries for Electric Energy Storage, the charge and discharge performance of battery cell 10 was tested:

[0284] Step 1: Initialize the discharge of the battery cell according to 6.2.4.2.1 in GBT 36276-2023 Lithium-ion Batteries for Electric Energy Storage.

[0285] Step 2: Charge at a constant power of P rc until the charge cut-off condition of the battery cell is reached, let it stand for 10 minutes, and record the power, time, voltage, temperature, and initial charge energy.

[0286] Step 3: Discharge at a constant power of P rd until the discharge cut-off condition of the battery cell is reached, let it stand for 10 minutes, and record the power, time, voltage, temperature, and initial discharge energy.

[0287] Step 4: Disconnect the test sample from the charge and discharge device, remove the data sampling line, and take out the test sample.

[0288] Step 5: Repeat Steps 1 to 4 until all test samples are completed.

[0289] Step 6: Calculate the initial charge and discharge energy efficiency of each test sample based on the initial charge energy in Step 2 and the initial discharge energy in Step 3; calculate the average value of the initial charge energy, the average value of the initial discharge energy, the average value of the initial charge and discharge energy efficiency, the range of the initial charge energy, and the range of the initial discharge energy of all test samples; among them, the ratio of the initial discharge energy to the initial charge energy of battery cell 10 is the energy conversion efficiency value of battery cell 10.

[0290] Table 1

[0291]

[0292] It can be seen from the comparison between Comparative Example 1 and Examples 1-22, between Examples 1-4, between Examples 5-10, between Examples 11-16, and between Examples 17-22 respectively that, compared with the minimum overcurrent area of terminal body 31 being 38.5 mm 2 and the capacitance of battery cell 10 being greater than 1500 Ah, when the minimum overcurrent area of terminal body 31 is greater than or equal to 63 mm 2 and the capacitance of battery cell 10 is between 500 Ah and 1500 Ah, the energy conversion efficiency of battery cell 10 is greater than or equal to 94.9%, which can effectively improve the energy conversion efficiency of battery cell 10; when the capacitance of battery cell 10 is certain, the larger the minimum overcurrent area of terminal body 31, the higher the energy conversion efficiency of battery cell 10.

[0293] When the minimum overcurrent area of the battery cell 10 is 63 mm 2 , the larger the capacitance of the battery cell 10, the lower the energy conversion efficiency of the battery cell 10. And when the capacitance of the battery cell is 1500 Ah, the energy conversion efficiency of the battery cell 10 reaches 94.9%. When the minimum overcurrent area of the battery cell 10 is 95 mm 2 , the larger the capacitance of the battery cell 10, the lower the energy conversion efficiency of the battery cell 10. And when the capacitance of the battery cell is 1500 Ah, the energy conversion efficiency of the battery cell 10 reaches 95%. When the minimum overcurrent area of the battery cell 10 is 177 mm 2 , the larger the capacitance of the battery cell 10, the lower the energy conversion efficiency of the battery cell 10. And when the capacitance of the battery cell is 1500 Ah, the energy conversion efficiency of the battery cell 10 reaches 95.1%. When the minimum overcurrent area of the battery cell 10 is 283 mm 2 , the larger the capacitance of the battery cell 10, the lower the energy conversion efficiency of the battery cell 10. And when the capacitance of the battery cell is 1500 Ah, the energy conversion efficiency of the battery cell 10 reaches 95.2%. When the minimum overcurrent area of the battery cell 10 is 415 mm 2 , the larger the capacitance of the battery cell 10, the lower the energy conversion efficiency of the battery cell 10. And when the capacitance of the battery cell is 1500 Ah, the energy conversion efficiency of the battery cell 10 reaches 95.25%. When the minimum overcurrent area of the battery cell 10 is 491 mm 2 , the larger the capacitance of the battery cell 10, the lower the energy conversion efficiency of the battery cell 10. And when the capacitance of the battery cell is 1500 Ah, the energy conversion efficiency of the battery cell 10 reaches 95.35%. Therefore, when the minimum overcurrent area of the battery cell 10 meets certain requirements, the smaller the capacitance of the battery cell 10, the higher the energy conversion efficiency of the battery cell 10.

[0294] It should be noted that, without conflict, the embodiments in this application and the features in the embodiments can be combined with each other.

[0295] The above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit this application. For those skilled in the art, this application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included within the protection scope of this application.

Claims

1. A battery cell, characterized in that, include: The housing has a first wall, wherein the first wall is provided with a first lead-out hole; an electrode assembly, contained in the housing; a first electrode terminal, arranged on the first wall, comprising a first stopper and a terminal body which are separately arranged and connected, the first stopper being located on a side of the first wall away from the electrode assembly, the terminal body being passed through the first lead-out hole and connected to the first stopper, and the terminal body being electrically connected to the electrode assembly; Among them, the minimum overcurrent area S of the terminal body is 63 mm 2 - 491 mm 2 , and the capacitance C of the battery cell is 500 Ah - 1500 Ah.

2. The battery cell according to claim 1, characterized in that, The capacity C of the battery cell and the minimum flow area S of the terminal body meet any of the following conditions: (1) 500 Ah ≤ C < 800 Ah, and 63 mm 2 ≤ S ≤ 283 mm 2 ; (2) 800 Ah ≤ C < 1200 Ah, and 95 mm 2 ≤ S ≤ 415 mm 2 ; (3) 1200 Ah ≤ C ≤ 1500 Ah, and 177 mm 2 ≤ S ≤ 491 mm 2 .

3. The battery cell according to claim 1, characterized in that, The internal resistance R of the battery cell is 0.03mΩ-0.13mΩ.

4. The battery cell according to claim 1, wherein, The first limiting member includes a first part and a second part, the first part and the second part are made of different materials, the first part is used to connect with an external component, the second part is made of the same material as the terminal body, and the second part is welded to the terminal body.

5. The battery cell according to claim 4, characterized in that, The material of the first part is aluminum; and / or the material of the second part is copper.

6. The battery cell according to any one of claims 1-5, characterized in that, The first limiting member is provided with a mounting hole, and the terminal body includes a first guide portion and a second guide portion, the first guide portion is passed through the mounting hole and is connected to the first limiting member, the second guide portion is passed through the first lead-out hole, the first guide portion is protruded at one end of the second guide portion away from the electrode assembly, and the position where the flow area of ​​the terminal body is the smallest is located at the first guide portion.

7. The battery cell according to claim 6, wherein The second guide portion has a first abutment surface, the first guide portion is protruded from the first abutment surface, the first guide portion has a second abutment surface facing the first abutment surface, the first abutment surface and the second abutment surface cooperate to clamp a part of the first limiting member to limit the movement of the first limiting member relative to the terminal body along the thickness direction of the first wall.

8. The battery cell according to claim 7, characterized in that, The first guide portion includes a first guide section and a second guide section, the first guide section is protruding from the first abutment surface, the first guide section connects the second guide section and the second guide portion, the second guide section is close to one end of the first guide section to form the second abutment surface, the diameter of the first guide section is smaller than the diameter of the second guide section, and the position where the flow area of ​​the terminal body is the smallest is located in the first guide section.

9. The battery cell according to claim 8, wherein, A difference between a diameter of the second guide section and a diameter of the first guide section is D1, and 1 mm ≤ D1 ≤ 10 mm.

10. The battery cell according to claim 6, wherein, The terminal body also includes a third guide portion, which is located on the side of the first wall facing the electrode assembly, the second guide portion connects the third guide portion and the first guide portion, and the third guide portion and the first limiting member cooperate to clamp the first wall.

11. The battery cell according to claim 10, wherein The first air guide portion, the second air guide portion and the third air guide portion are integrally formed.

12. The battery cell according to any one of claims 1-3, characterized in that, The first limiting member is provided with a mounting hole, the terminal body comprises a first guide portion and a second guide portion, the first guide portion is inserted into the mounting hole and connected to the first limiting member, the second guide portion is inserted into the first lead-out hole, the first guide portion is convexly arranged at an end of the second guide portion away from the electrode assembly, and the position of the terminal body with the smallest flow area is located at the first guide portion; The first stopper comprises a first part and a second part, the first part and the second part are made of different materials, the first part is used to connect with an external component, and the second part is made of the same material as the terminal body; The mounting hole includes a first hole segment located in the first part and a second hole segment located in the second part, the first hole segment is closer to the electrode assembly than the second hole segment, and the portion of the first guide portion located in the second hole segment is welded to the second part.

13. The battery cell according to claim 12, wherein The minimum distance between the outer circumference of the second portion and the hole wall of the second hole segment is D2, 1mm≤D2≤10mm.

14. The battery cell according to claim 12, wherein, Along a first direction, a minimum width of the second portion is 14 mm to 30 mm, and the first direction is perpendicular to a thickness direction of the first wall.

15. The battery cell according to claim 12, wherein The battery cell further includes a second electrode terminal having a polarity opposite to that of the first electrode terminal, the second electrode terminal being disposed on the first wall and spaced apart from the first electrode terminal along a first direction, the first direction being perpendicular to a thickness direction of the first wall; The first portion has a first surface facing away from the electrode assembly, the first surface is located on a side of the second portion facing away from the second electrode terminal, and along the first direction, a width of the first surface is 10 mm-100 mm.

16. The battery cell according to claim 12, wherein, A receiving groove is provided on a side of the first part away from the electrode assembly, the first hole section extends to the bottom surface of the receiving groove at one end away from the electrode assembly, and at least part of the second part is received in the receiving groove.

17. The battery cell according to claim 12, wherein In a projection plane perpendicular to the thickness direction of the first wall, a sum of a projection area of ​​an orthographic projection of the second portion and an orthographic projection of the first guide portion is less than or equal to a projection area of ​​an orthographic projection of the second guide portion.

18. The battery cell according to any one of claims 1-5, characterized in that, The ratio of the capacitance C of the battery cell to the minimum overcurrent area S of the terminal body is 2 Ah / mm 2 - 7 Ah / mm 2 .

19. The battery cell according to any one of claims 1-5, characterized in that, The battery cell further includes a second electrode terminal having a polarity opposite to that of the first electrode terminal, the first wall is provided with a second lead-out hole, the second lead-out hole is spaced apart from the first lead-out hole along a first direction, the second electrode terminal is passed through the second lead-out hole, and the first direction is perpendicular to a thickness direction of the first wall; Along the first direction, a ratio of a center distance between the second lead-out hole and the first lead-out hole to a size of the electrode assembly is 0.35-0.

8.

20. The battery cell according to any one of claims 1-5, characterized in that, The battery cell also includes a connector, the electrode assembly is provided with a tab, at least part of the connector is located between the tab and the terminal body, the tab, the connector and the terminal body are welded to form a first connection portion, and the first connection portion connects the connector, the tab and the terminal body.

21. The battery cell according to any one of claims 1-5, characterized in that, The cross-section where the minimum current-carrying area S of the terminal body is located is a circular surface, the diameter of the circular surface is 9 mm - 25 mm, and the cross-section is perpendicular to the thickness direction of the first wall.

22. A battery device, characterized in that, It includes a battery cell as described in any one of claims 1 - 21.

23. The battery device according to claim 22, wherein The battery device includes a busbar component and a plurality of the battery cells. The busbar component is electrically connected to the plurality of battery cells. The first limiting member of the first electrode terminal of at least one of the battery cells is connected to the busbar component. And in the projection plane perpendicular to the thickness direction of the first wall, the area of the overlapping portion of the orthographic projection of the first limiting member and the orthographic projection of the busbar component connected to the first limiting member is 300 mm 2 - 3000 mm 2 .

24. An energy storage device, characterized in that, It includes a battery cell as described in any one of claims 1 - 21 or a battery device as described in claim 22 or 23.

25. A energy storage system, characterized in that, It includes a power conversion device and a energy storage device as described in claim 24, and the power conversion device is used to electrically connect a power generation device and the energy storage device.

26. A charging network, characterized in that, It includes a charging pile and a energy storage device as described in claim 24, and the energy storage device is used to provide electric energy for the charging pile.

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