Battery monomer, battery and electric device

Abstract

The utility model provides a battery monomer, a battery and a power utilization device, and belongs to the technical field of batteries. Wherein the battery monomer comprises a shell, a first pole and a second pole, the first pole comprises a first penetrating part penetrating through the shell, and a first inner fixing part and a first outer fixing part which are connected with the first penetrating part and are respectively arranged on the inner side and the outer side of the shell, and the second pole comprises a second penetrating part penetrating through the shell; the second inner fixing part and the second outer fixing part are connected with the second penetrating part and arranged on the inner side and the outer side of the shell respectively, the material strength of the first inner fixing part is smaller than that of the second inner fixing part, and the wall thickness of the first inner fixing part is larger than that of the second inner fixing part. According to the single battery, on the premise that the capacity of the single battery and the voltage withstanding level of the second pole are not influenced, the wall thickness of the second inner fixing part with relatively high material strength is reduced, so that the material cost and the weight of the second pole are reduced.

Description

Technical Field

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

[0002] In recent years, new energy vehicles have developed by leaps and bounds. In the field of electric vehicles, power batteries, as the power source of electric vehicles, play an irreplaceable and important role. Among them, power batteries include several battery cells. However, it is difficult to balance the reliability and cost of battery cells. Utility Model Content

[0003] The embodiments of the present application provide a battery cell, a battery, and an electrical device, which can take into account both the reliability and low cost of the battery cell.

[0004] In a first aspect, an embodiment of the present application provides a battery cell, comprising: a shell, a first pole and a second pole, the first pole comprising a first penetration portion passing through the shell, and a first inner fixing portion and a first outer fixing portion connected to the first penetration portion and respectively arranged on the inner and outer sides of the shell, the second pole comprising a second penetration portion passing through the shell, and a second inner fixing portion and a second outer fixing portion connected to the second penetration portion and respectively arranged on the inner and outer sides of the shell, the material strength of the first inner fixing portion is less than the material strength of the second inner fixing portion, and the wall thickness of the first inner fixing portion is greater than the wall thickness of the second inner fixing portion.

[0005] In the above technical solution, since the capacity of the battery cell can be determined by the wall thickness of the first fixing part with relatively weak material strength, the present application sets the wall thickness of the second inner fixing part with relatively strong material strength to be smaller than the wall thickness of the first inner fixing part with relatively weak material strength, so as to reduce the material cost and weight of the second pole without affecting the capacity of the battery cell and the withstand voltage level of the second pole, thereby facilitating the reduction of the material cost and weight of the second pole. At the same time, since the wall thickness of the first inner fixing part with relatively weak material strength is greater than the wall thickness of the second inner fixing part with relatively strong material strength, the withstand voltage level of the first pole also meets the requirements.

[0006] In some embodiments, the first penetration portion defines a first accommodating groove, which is open toward the inner side or the outer side of the shell, and the first penetration portion includes a first end wall portion arranged opposite to the opening of the first accommodating groove, the first internal fixing portion is made of the same main body material as the first end wall portion, and the wall thickness of the first end wall portion is greater than the wall thickness of the first internal fixing portion.

[0007] In the above technical solution, by setting the wall thickness of the first end wall of the first pole to be greater than the wall thickness of the first inner fixing part, it is equivalent to increasing the wall thickness of the center of the first pole while meeting the pressure resistance level at the edge of the first pole, so that the center of the first pole can show better structural strength when the area is large, thereby improving the reliability of the first pole. In other words, by setting the wall thickness of the first inner fixing part to be less than the wall thickness of the first end wall of the first pole, it is equivalent to reducing the wall thickness of the edge of the first pole while meeting the structural strength at the center of the first pole, thereby saving materials, reducing costs, and reducing the height space occupied by the edge of the first pole in the shell, thereby improving the capacity of the battery cell.

[0008] In some embodiments, a first through hole connecting the inner side of the shell and the first receiving groove is formed on the first end wall portion, and the battery cell assembly of the battery cell includes a first conductive portion electrically connected to the first pole, the first conductive portion is passed through the first through hole, and includes a first connecting section received in the first receiving groove, the first connecting section is overlapped on the first end wall portion and welded to the first end wall portion.

[0009] In the above technical solution, the first through hole is provided so that the first conductive part extends into the first accommodating groove, and the first accommodating groove can accommodate the first conductive part, thereby reducing the height space occupied by the first conductive part in the accommodating cavity and improving the capacity of the battery cell. Moreover, by setting the wall thickness of the first internal fixed part to be smaller than the wall thickness of the first end wall, the relatively thick first end wall can be strengthened to meet the welding penetration and structural strength. At the same time, the relatively thin first internal fixed part is thinned relative to the first end wall. On the premise of meeting the pressure resistance level, the capacity of the battery cell is improved and the material cost is reduced.

[0010] In some embodiments, the first end wall portion is arranged close to the inner side of the shell relative to the first accommodating groove, and the inner end surface of the first inner fixing portion is flush with the inner end surface of the first end wall portion.

[0011] In the above technical solution, by setting the side surface of the first inner fixing portion close to the accommodating cavity to be flush with the side surface of the first end wall portion close to the accommodating cavity, the processing of the first pole can be simplified, the processing difficulty can be reduced, and the production cost can be reduced. Moreover, since the inner end surface of the first end wall portion does not protrude from the inner end surface of the first inner fixing portion in the direction of the accommodating cavity, the height space occupied by the center of the first pole in the shell is reduced, thereby reducing the risk of short circuit between the first pole and the battery cell assembly.

[0012] In some embodiments, the first end wall portion is made of aluminum and has a wall thickness of 2.2 mm to 0.8 mm, and the wall thickness of the first inner fixing portion is 2 mm to 0.8 mm.

[0013] In the above technical solution, the wall thickness of the first end wall portion is not too large, so that the volume of the first accommodating groove is not too small, meeting the storage requirement for the first conductive part; the wall thickness of the first end wall portion is not too small, so that the first end wall portion can meet the welding penetration requirement with the first conductive part and the structural strength requirement of the first end wall portion; the wall thickness of the first internal fixed portion is not too large, so as to reduce the height space occupied by the first internal fixed portion to the accommodating cavity, increase the capacity of the battery cell, and reduce the material cost; the wall thickness of the first internal fixed portion is not too small, so as to meet the pressure resistance level of the first pole, and improve the problem of the first pole escaping from the shell due to the high pressure in the shell.

[0014] In some embodiments, the wall thickness of the first end wall portion is 2.2 mm, and the wall thickness of the first inner fixing portion is 2 mm.

[0015] In the above technical solution, by setting the wall thickness of the first end wall portion to 2.2 mm and the wall thickness of the first inner fixed portion to 2 mm, the storage requirement for the first conductive portion can be better met, and the first end wall portion can meet the welding penetration requirement with the first conductive portion and the structural strength requirement of the first end wall portion, and the first inner fixed portion occupies a small height space of the accommodating cavity, thereby increasing the capacity of the battery cell and reducing the material cost. It can also meet the pressure resistance level of the first pole and improve the problem of the first pole escaping from the shell due to the high pressure inside the shell.

[0016] In some embodiments, the second penetration portion defines a second accommodating groove, which is open toward the inner side or the outer side of the shell, and the second penetration portion includes a second end wall portion arranged opposite to the opening of the second accommodating groove, the second inner fixing portion is made of the same main body material as the second end wall portion, and the wall thickness of the second end wall portion is smaller than the wall thickness of the second inner fixing portion.

[0017] In the above technical solution, by setting the wall thickness of the second end wall of the second pole to be smaller than the wall thickness of the second inner fixing part, it is equivalent to reducing the wall thickness of the second end wall with relatively large material strength under the premise of meeting the pressure resistance level at the edge of the second pole, and reducing the material cost of the second pole under the premise of meeting the structural strength of the second end wall, and increasing the volume of the second receiving groove. In other words, by setting the wall thickness of the second inner fixing part to be larger than the wall thickness of the second end wall of the second pole, it is equivalent to increasing the wall thickness of the second inner fixing part under the premise of meeting the structural strength of the second end wall, thereby improving the pressure resistance level of the second pole, and at the same time, because the wall thickness of the second inner fixing part is smaller than the wall thickness of the first inner fixing part, even if the wall thickness of the second inner fixing part is increased, it will not increase the height space occupied in the shell, so that the capacity of the battery cell can be guaranteed.

[0018] In some embodiments, a second through hole connecting the inner side of the shell and the second receiving groove is formed on the second end wall portion, and the battery cell assembly of the battery cell includes a second conductive portion connected to the second pole, the second conductive portion is passed through the second through hole, and includes a second connecting section received in the second receiving groove, and the second connecting section is overlapped on the second end wall portion and welded to the second end wall portion.

[0019] In the above technical solution, by providing the second through hole so that the second conductive part extends into the second receiving groove, the second receiving groove can play the role of receiving the second conductive part, reducing the height space occupied by the second conductive part in the receiving cavity, and improving the capacity of the battery cell. And because the wall thickness of the second end wall of the second pole is less than the wall thickness of the second inner fixing part, the volume of the second receiving groove can be increased under the premise that the pressure resistance level of the second pole at the edge is sufficient, so as to facilitate receiving the second conductive part to a greater extent and facilitate welding of the second connecting section and the second end wall.

[0020] In some embodiments, the second end wall portion is arranged close to the inner side of the shell relative to the second accommodating groove, and the inner end surface of the second inner fixing portion is flush with the inner end surface of the second end wall portion.

[0021] In the above technical solution, by setting the side surface of the second inner fixing portion close to the accommodating cavity to be flush with the side surface of the second end wall portion close to the accommodating cavity, the processing of the second pole can be simplified, the processing difficulty can be reduced, and the production cost can be reduced. Moreover, since the inner end surface of the second end wall portion does not protrude from the inner end surface of the second inner fixing portion in the direction of the accommodating cavity, the height space occupied by the center of the second pole in the shell is reduced, thereby reducing the risk of short circuit between the second pole and the battery cell assembly.

[0022] In some embodiments, the second end wall portion is made of copper and has a wall thickness of 1.3 mm to 0.8 mm, and the wall thickness of the second inner fixing portion is 1.6 mm to 0.8 mm.

[0023] In the above technical solution, the wall thickness of the second end wall portion is not too large, so that the volume of the second accommodating groove is larger, the storage requirement for the second conductive part is improved, and the material cost is low. The wall thickness of the second end wall portion is not too small, so that the second end wall portion can meet the welding penetration requirement with the second conductive part and the structural strength requirement of the second end wall portion. The wall thickness of the second inner fixed portion is not too large, so as to reduce the height space occupied by the second inner fixed portion to the accommodating cavity, increase the capacity of the battery cell, and reduce the material cost. The wall thickness of the second inner fixed portion is not too small, so as to meet the pressure resistance level of the second pole and improve the problem of the second pole escaping from the shell due to the high pressure in the shell.

[0024] In some embodiments, the wall thickness of the second end wall portion is 1.2 mm, and the wall thickness of the second inner fixing portion is 1.5 mm.

[0025] In the above technical scheme, the storage requirements for the second conductive part can be better met, and the second end wall can meet the welding penetration requirements with the second conductive part and the structural strength requirements of the second end wall, and reduce the material cost of the second end wall, and make the second internal fixed part occupy a small height space of the accommodating cavity, thereby increasing the capacity of the battery cell and reducing the material cost. It can also meet the pressure resistance level of the second pole and improve the problem of the second pole escaping from the shell due to the high pressure inside the shell.

[0026] In some embodiments, the first penetration portion defines a first accommodating groove, the first accommodating groove is open toward the inner side or the outer side of the shell, the first penetration portion includes a first end wall portion arranged opposite to the opening of the first accommodating groove, and the second penetration portion defines a second accommodating groove, the second accommodating groove is open toward the inner side or the outer side of the shell, and the second penetration portion includes a second end wall portion arranged opposite to the opening of the second accommodating groove, wherein the material strength of the first end wall portion is less than the material strength of the second end wall portion, and the wall thickness of the first end wall portion is greater than the wall thickness of the second end wall portion.

[0027] In the above technical solution, since the material strength of the first end wall portion is less than that of the second end wall portion, if the inflation process is simulated, the first end wall portion is not easily deformed, and the wall thickness of the second end wall portion of the second pole is smaller than the wall thickness of the first end wall portion of the first pole and is not easily deformed. Therefore, the wall thickness of the second end wall portion is set to be smaller than the wall thickness of the first end wall portion, which can effectively increase the volume of the second accommodating groove and reduce the material cost and weight of the second pole.

[0028] In some embodiments, the material strength of the first external fixing portion is smaller than the material strength of the second external fixing portion, and the wall thickness of the first external fixing portion is larger than the wall thickness of the second external fixing portion.

[0029] In the above technical solution, since the material strength of the first external fixing part is less than the material strength of the second external fixing part, when the wall thickness of the first external fixing part makes the structural strength of the first external fixing part meet the requirements, the structural strength requirements of the second external fixing part can also be met by setting the wall thickness of the second external fixing part to be smaller than the wall thickness of the first external fixing part. Therefore, by thinning the second external fixing part relative to the first external fixing part, the material cost and weight of the second pole can be reduced while meeting the structural strength requirements.

[0030] In some embodiments, the shell has a first mounting hole for the first penetration portion to penetrate, the first penetration portion includes a first surrounding wall portion extending along the circumference of the first mounting hole, and a first accommodating groove is formed in the first surrounding wall portion; the shell has a second mounting hole for the second penetration portion to penetrate, the second penetration portion includes a second surrounding wall portion extending along the circumference of the second mounting hole, and a second accommodating groove is formed in the second surrounding wall portion; wherein the material strength of the first surrounding wall portion is less than the material strength of the second surrounding wall portion, and the wall thickness of the first surrounding wall portion is greater than the wall thickness of the second surrounding wall portion.

[0031] In the above technical solution, since the material strength of the first surrounding wall portion is less than the material strength of the second surrounding wall portion, when the wall thickness of the first surrounding wall portion makes the structural strength of the first surrounding wall portion meet the requirements, the structural strength of the second surrounding wall portion can also meet the requirements by setting the wall thickness of the second surrounding wall portion to be smaller than the wall thickness of the first surrounding wall portion. Therefore, by thinning the second surrounding wall portion relative to the first surrounding wall portion, the material cost and weight of the second pole can be reduced while meeting the structural strength requirements, and the volume of the second accommodating groove can be increased.

[0032] In some embodiments, the first pole is an integral part with the same main body material at all locations, and the second pole is an integral part with the same main body material at all locations, and the material strength of the second pole is greater than the material strength of the first pole.

[0033] In the above technical solution, the processing difficulty and manufacturing cost of the first pole and the second pole can be reduced, and the material strength of the second pole at each location is greater than the material strength of the first pole at each location, so that the wall thickness of the second pole can be reduced to a greater extent, which is more conducive to reducing the material cost and weight of the second pole.

[0034] In some embodiments, the first pole is a positive pole, and a main material of the first pole is aluminum; the second pole is a negative pole, and a main material of the second pole is copper.

[0035] In the above technical solution, since the material strength of aluminum is lower than that of copper, or in other words, the material strength of copper is higher than that of aluminum, the requirement that the material strength of the negative electrode column is greater than that of the positive electrode column can be met, which is beneficial to reducing the material cost and weight of the negative electrode column.

[0036] In some embodiments, a first pole cover is welded to the outside of the first pole, the first pole cover is an aluminum cover and is suitable for welding to a collector component, a second pole cover is welded to the outside of the second pole, the second pole cover is a copper-aluminum composite cover and is welded to the second pole through a copper portion, and the aluminum portion of the second pole cover is suitable for welding to a collector component.

[0037] In the above technical solution, it is beneficial to weld the pole cover plate with the pole and the current collecting component.

[0038] In some embodiments, the shell includes a first shell wall, and the first pole and the second pole are both arranged on the first shell wall.

[0039] In the above technical solution, by installing the first pole and the second pole on the shell wall on the same side, the processing can be simplified, the processing difficulty can be reduced, the processing efficiency can be improved, and the height space occupied in the shell can be reduced, thereby increasing the capacity of the battery cell.

[0040] In a second aspect, an embodiment of the present application further provides a battery, comprising a battery cell of any of the above-mentioned solutions.

[0041] In the above technical solution, since the reliability and low cost of the battery cell according to the embodiment of the present application can be taken into account, it is beneficial to improve the performance of the battery and reduce the cost of the battery.

[0042] In a third aspect, an embodiment of the present application further provides an electrical device, comprising a battery according to any of the above solutions.

[0043] In the above technical solution, since the performance of the battery is improved and the cost is reduced, it is beneficial to improve the working power performance of the electrical device and reduce the cost of the electrical device. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1 A schematic diagram of the structure of a vehicle provided in some embodiments of the present application;

[0046] Figure 2 An exploded view of the structure of a battery provided in some embodiments of the present application;

[0047] Figure 3 A schematic diagram of the structure of a battery cell provided in some embodiments of the present application;

[0048] Figure 4 for Figure 3 The structural explosion diagram of the battery cell shown in;

[0049] Figure 5 A schematic diagram of an orthographic projection of a battery cell provided in some embodiments of the present application;

[0050] Figure 6 For along Figure 5 Sectional view along line AA;

[0051] Figure 7 for Figure 6 A partial enlarged view of the B part circled in the middle;

[0052] Figure 8 for Figure 6 A partial enlarged view of the C section circled in the middle;

[0053] Fig. 9 For along Figure 5 Sectional view along line EE;

[0054] Fig.10 for Figure 6 A partial enlarged view of the D portion indicated by the middle circle;

[0055] Fig.11 For along Figure 5 Cross-sectional view along line FF.

[0056] Figures: vehicle 1000; first direction X; second direction Y; third direction Z; battery 100; controller 200; motor 300; box 101; first box body 1011; second box body 1012; battery cell 102; shell 1; accommodating chamber 10; first mounting hole 111; second mounting hole 112; first shell wall 11; second shell wall 12; third shell wall 13; pole 2; first pole 21; first through-set portion 211; first inner fixing portion 212; first outer fixing portion 213; first accommodating groove 2111; first end wall portion 2112; first surrounding wall portion 2113; first through-hole 2114; second pole 22; second through-set portion Part 221; second inner fixing part 222; second outer fixing part 223; second accommodating groove 2211; second end wall part 2212; second surrounding wall part 2213; second through hole 2214; sealing insulation component 3; first insulating part 31; second insulating part 32; sealing ring 33; battery cell assembly 4; active material coating part 41; conductive part 42; first conductive part 421; first connecting section 4211; second conductive part 422; second connecting section 4221; first pole cover 51; injection hole 511; second pole cover 52; copper part 521; aluminum part 522; sealing structure 6; first sealing member 61; second sealing member 62; pressure relief structure 7. DETAILED DESCRIPTION

[0057] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0058] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as those commonly understood by technicians in the technical field of this application; 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" in the specification and claims of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary and secondary relationship.

[0059] Reference to "embodiment" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments.

[0060] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "attached" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be a communication between the inner sides of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0061] The term "and / or" in this application is only 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 at the same time, and B exists alone. In addition, the character " / " in this application generally indicates that the associated objects before and after are in an "or" relationship.

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

[0063] The term "plurality" used in the present application refers to two or more (including two).

[0064] In the present application, battery cells may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries or magnesium-ion batteries, etc., and the embodiments of the present application do not limit this. Battery cells may be cylindrical, flat, rectangular or other shapes, etc., and the embodiments of the present application do not limit this. Battery cells are generally divided into three types according to the packaging method: cylindrical battery cells, square battery cells and soft-pack battery cells, and the embodiments of the present application do not limit this.

[0065] The battery mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells to provide higher voltage and capacity. For example, the battery mentioned in the present application may include a battery module or a battery pack. A battery module generally includes a plurality of battery cells. A battery pack generally includes a box for encapsulating one or more battery cells or one or more battery modules. The box can prevent liquid or other foreign matter from affecting the charging or discharging of the battery cells.

[0066] The battery cell includes a shell, a battery cell assembly and an electrolyte. The shell is used to contain the battery cell assembly and the electrolyte. The battery cell assembly includes at least one electrode assembly, which is composed of a positive electrode sheet, a negative electrode sheet and a separator. The electrode assembly can be a wound structure or a stacked structure. The battery cell mainly works by the movement of metal ions between the positive electrode sheet and the negative electrode sheet.

[0067] The positive electrode sheet can generally include a positive electrode current collector and a positive electrode active material layer, the positive electrode active material layer is directly or indirectly coated on the positive electrode current collector, the positive electrode current collector not coated with the positive electrode active material layer protrudes from the positive electrode current collector coated with the positive electrode active material layer, and the positive electrode current collector not coated with the positive electrode active material layer serves as a positive electrode tab. Taking lithium-ion batteries as an example, the material of the positive electrode current collector can be aluminum, and the material of the positive electrode active material layer can be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganese oxide, etc.

[0068] The negative electrode sheet may generally include a negative electrode current collector and a negative electrode active material layer, wherein the negative electrode active material layer is directly or indirectly coated on the negative electrode current collector, and the negative electrode current collector not coated with the negative electrode active material layer protrudes from the negative electrode current collector coated with the negative electrode active material layer, and the negative electrode current collector not coated with the negative electrode active material layer serves as a negative electrode tab. The material of the negative electrode current collector may be copper, and the material of the negative electrode active material layer may be carbon or silicon, etc.

[0069] In order to ensure that a large current can pass without melting, the number of positive pole ears is multiple and stacked together to form the positive pole ear portion, and the number of negative pole ears is multiple and stacked together to form the negative pole ear portion. A pole column is provided on the shell, and the positive pole ear portion is electrically connected to the positive pole column, and the negative pole ear portion is electrically connected to the negative pole column. For example, the pole ear portion can be connected to the pole column to form a direct electrical connection between the pole ear portion and the pole column. For another example, the battery cell assembly may include a transfer plate, the pole ear portion is connected to the transfer plate, and the transfer plate is connected to the pole column to form an indirect electrical connection between the pole ear portion and the pole column.

[0070] The material of the isolation film is not limited, for example, it can be polypropylene or polyethylene.

[0071] In the battery cell in the related art, the pole is installed in the shell. If the pole has insufficient pressure resistance, when the pressure in the shell is high, the pole is easily squeezed out, and when the area of ​​the pole is large, the pole has a lower pressure resistance, and is more likely to be squeezed out by the gas in the shell. To this end, in the embodiment of the present application, different wall thickness designs are performed for poles with different material strengths, so that the wall thickness of the inner fixing part of the pole with relatively weak material strength is relatively thick, thereby improving its pressure resistance and reducing the risk of it escaping from the shell, while the wall thickness of the inner fixing part of the pole with relatively strong material strength is relatively thin, so that the material cost and weight can be reduced while meeting its pressure resistance, and the space occupied by it in the shell can be saved, thereby improving the reliability of the battery cell and reducing the production cost of the battery cell.

[0072] Material strength is a physical property of the material itself, which refers to the yield strength of the material. It can be obtained by looking up a table or testing, for example, there are at least two ways to obtain it. For example, method one can use the inductively coupled plasma reflection spectroscopy method to analyze the trace elements of the material, and then use the table lookup method to determine the strength of the material. For example, aluminum materials can be checked in GB / T 3880 "Aluminum and aluminum alloy plates, strips, and foils" standard; copper materials can be checked in GB / T 5231 "Processing copper and copper alloy grades and chemical composition" standard. For example, method two uses GB228-87 "Metal Tensile Test Method" to test the yield strength of the material.

[0073] The embodiment of the present application provides an electric device using a battery as a power source, and the electric device may be, but is not limited to, a mobile phone, a tablet, a laptop, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft, etc. Among them, the electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, etc., and the spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0074] For the convenience of description, the following embodiments are described by taking a vehicle 1000 as an example of an electrical device according to an embodiment of the present application.

[0075] Please refer to Figure 1 , Figure 1 A schematic diagram of the structure of a vehicle 1000 provided for some embodiments of the present application. The vehicle 1000 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 100 is provided on the inner side of the vehicle 1000, and the battery 100 may be provided at the bottom, head or tail of the vehicle 1000. The battery 100 may be used to power the vehicle 1000, for example, the battery 100 may be used as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300, and the controller 200 is used to control the battery 100 to power the motor 300, for example, for starting, navigating and driving the vehicle 1000.

[0076] In some embodiments of the present application, the battery 100 can not only serve as an operating power source for the vehicle 1000, but also serve as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0077] Please refer to Figure 2 , Figure 2 An exploded view of the structure of a battery 100 provided for some embodiments of the present application. The battery 100 includes a case 101 and a plurality of battery cells 102, and the battery cells 102 are accommodated in the case 101. Among them, the case 101 is used to provide an assembly space for the battery cells 102, and the case 101 can adopt a variety of structures. In some embodiments, the case 101 may include a first case body 1011 and a second case body 1012, and the first case body 1011 and the second case body 1012 cover each other, and the first case body 1011 and the second case body 1012 jointly define an assembly space for accommodating the battery cells 102. The second box body 1012 may be a hollow structure with one end open, the first box body 1011 may be a plate-like structure, and the first box body 1011 covers the open side of the second box body 1012, so that the first box body 1011 and the second box body 1012 jointly define an assembly space; the first box body 1011 and the second box body 1012 may also be hollow structures with one side open, and the open side of the first box body 1011 covers the open side of the second box body 1012. Of course, the box body 101 formed by the first box body 1011 and the second box body 1012 may be in various shapes, such as a cylinder, a cuboid, etc.

[0078] In the battery 100, multiple battery cells 102 can be connected in series, in parallel, or in a hybrid connection. A hybrid connection means that multiple battery cells 102 are connected in series and in parallel. Multiple battery cells 102 can be directly connected in series, in parallel, or in a hybrid connection, and then the whole formed by multiple battery cells 102 is accommodated in the box 101; of course, the battery 100 can also be a battery module formed by multiple battery cells 102 connected in series, in parallel, or in a hybrid connection, and then multiple battery modules are connected in series, in parallel, or in a hybrid connection to form a whole, and accommodated in the box 101. The battery 100 may also include other structures, for example, the battery 100 may also include a busbar component for realizing electrical connection between multiple battery cells 102.

[0079] Each battery cell 102 may be a secondary battery or a primary battery; it may also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto. The battery cell 102 may be cylindrical, flat, or rectangular. For example, Figure 3 The schematic diagram of the structure of the battery cell provided in some embodiments of the present application is shown in FIG. Figure 3 In the illustrated embodiment, the length direction of the battery cell 102 is the first direction X, the width direction of the battery cell 102 is the second direction Y, and the height direction of the battery cell 102 is the third direction Z. The first direction X, the second direction Y and the third direction Z are perpendicular to each other.

[0080] Figure 4 for Figure 3 The structural explosion diagram of the battery cell 102 shown in FIG. Figure 5 This is a schematic diagram of an orthographic projection of a battery cell 102 provided in some embodiments of the present application. Figure 6 For along Figure 5 The cross-sectional view along the AA line. Figure 7 for Figure 6 The enlarged view of the part B shown in the circle. In some embodiments of the present application, Figure 3-Figure 7 The battery cell 102 includes: a shell 1 and a pole 2, the pole 2 is arranged in the shell 1, and a receiving cavity 10 is formed on the inner side of the shell 1. Exemplarily, the battery cell 102 includes a battery cell assembly 4, and the battery cell assembly 4 may include an active material coating part 41 and a conductive part 42 connected to the active material coating part 41, the active material coating part 41 is received in the receiving cavity 10, and the conductive part 42 is welded to the pole 2, so that the conductive part 42 is electrically connected between the active material coating part 41 and the pole 2. It can be understood that the active material coating part 41 may include a current collector coated with an active material layer, and the conductive part 42 may include only a pole ear part, or may also include a pole ear part and a transition piece electrically connected to the pole ear part, etc., which is not limited here.

[0081] Combination Figure 3-Figure 6, the pole 2 arranged on the shell 1 includes a first pole 21 and a second pole 22. Exemplarily, the shell 1 may include a plurality of shell walls, and the first pole 21 and the second pole 22 may be arranged on the same shell wall, or may be arranged on different shell walls respectively. For example, the shell 1 may include a first shell wall 11, a second shell wall 12, and a third shell wall 13, the first shell wall 11 and the second shell wall 12 are opposite, the third shell wall 13 is connected between the first shell wall 11 and the second shell wall 12, and the cross-sectional shape of the third shell wall 13 is consistent with the contour shape of any one of the first shell wall 11 and the second shell wall 12, wherein the first pole 21 and the second pole 22 are both arranged on the first shell wall 11; or, the first pole 21 and the second pole 22 are both arranged on the same side surface of the third shell wall 13; or, the first pole 21 is arranged on the first shell wall 11, and the second pole 22 is arranged on the second shell wall 12 or the third shell wall 13; or, the first pole 21 and the second pole 22 are respectively arranged on different side surfaces of the third shell wall 13, and so on. To simplify the description, the following text mainly uses an example in which both the first pole 21 and the second pole 22 are arranged on the first shell wall 11. After reading the technical solutions in the following text, those skilled in the art can obviously understand other technical solutions in which the first pole 21 and the second pole 22 are not arranged on the first shell wall 11 at the same time.

[0082] Combination Figure 7 and Figure 8 The first pole 21 includes a first penetration portion 211 penetrated through the shell 1 , and a first inner fixing portion 212 and a first outer fixing portion 213 connected to the first penetration portion 211 and respectively disposed on the inner and outer sides of the shell 1 .

[0083] Exemplarily, the first pole 21 includes a first penetration portion 211, a first inner fixing portion 212 and a first outer fixing portion 213. The first shell wall 11 has a first mounting hole 111, and the first penetration portion 211 is penetrated in the first mounting hole 111, that is, at least part of the first penetration portion 211 is located in the first mounting hole 111, and the axial direction of the first mounting hole 111 is taken as the projection direction, and the plane perpendicular to the axial direction of the first mounting hole 111 is taken as the projection plane, and the orthographic projection of the first penetration portion 211 on the projection plane falls within the orthographic projection range of the first mounting hole 111 on the projection plane, so that the first penetration portion 211 can be penetrated in the first mounting hole 111.

[0084] The orthographic projection of the first inner fixing portion 212 on the projection plane and the orthographic projection of the first shell wall 11 on the projection plane have an intersection area, so that the portion of the first inner fixing portion 212 corresponding to the intersection area is directly opposite to the first shell wall 11, so that at least a portion of the first inner fixing portion 212 is directly opposite to the first shell wall 11, thereby preventing the first pole 21 from moving relative to the first shell wall 11 in the direction toward the first outer fixing portion 213 (i.e., moving outside the first shell wall 11). The orthographic projection of the first outer fixing portion 213 on the projection plane and the orthographic projection of the first shell wall 11 on the projection plane have an intersection area, so that the portion of the first outer fixing portion 213 corresponding to the intersection area is directly opposite to the first shell wall 11, so that at least a portion of the first outer fixing portion 213 is directly opposite to the first shell wall 11, thereby preventing the first pole 21 from moving relative to the first shell wall 11 in the direction toward the first inner fixing portion 212 (i.e., moving inside the first shell wall 11).

[0085] Combination Figure 7 and Figure 8 The second pole 22 includes a second penetration portion 221 penetrated through the shell 1 , and a second inner fixing portion 222 and a second outer fixing portion 223 connected to the second penetration portion 221 and respectively disposed on the inner and outer sides of the shell 1 .

[0086] Exemplarily, the second pole 22 includes a second penetration portion 221, a second inner fixing portion 222, and a second outer fixing portion 223. The first shell wall 11 has a second mounting hole 112, and the second penetration portion 221 is penetrated in the second mounting hole 112, that is, at least part of the second penetration portion 221 is located in the second mounting hole 112, and the axial direction of the second mounting hole 112 is used as the projection direction, and the plane perpendicular to the axial direction of the second mounting hole 112 is used as the projection plane. The orthographic projection of the second penetration portion 221 on the projection plane falls within the orthographic projection range of the second mounting hole 112 on the projection plane, so that the second penetration portion 221 can be penetrated in the second mounting hole 112.

[0087] The orthographic projection of the second inner fixing portion 222 on the projection plane and the orthographic projection of the first shell wall 11 on the projection plane have an intersection area, so that the portion of the second inner fixing portion 222 corresponding to the intersection area is directly opposite to the first shell wall 11, so that at least a portion of the second inner fixing portion 222 is directly opposite to the first shell wall 11, thereby preventing the second pole 22 from moving relative to the first shell wall 11 in the direction toward the second outer fixing portion 223 (i.e., moving outside the first shell wall 11). The orthographic projection of the second outer fixing portion 223 on the projection plane and the orthographic projection of the first shell wall 11 on the projection plane have an intersection area, so that the portion of the second outer fixing portion 223 corresponding to the intersection area is directly opposite to the first shell wall 11, so that at least a portion of the second outer fixing portion 223 is directly opposite to the first shell wall 11, thereby preventing the second pole 22 from moving relative to the first shell wall 11 in the direction toward the second inner fixing portion 222 (i.e., moving inside the first shell wall 11).

[0088] Combination Figure 7 and Figure 8 , the material strength of the first inner fixing portion 212 is less than the material strength of the second inner fixing portion 222, and the wall thickness t1 of the first inner fixing portion 212 is greater than the wall thickness t2 of the second inner fixing portion 222. That is to say, of the first inner fixing portion 212 and the second inner fixing portion 222, the material strength of the first inner fixing portion 212 is relatively small, and the material strength of the second inner fixing portion 222 is relatively large. At the same time, of the first inner fixing portion 212 and the second inner fixing portion 222, the wall thickness t1 of the first inner fixing portion 212 is relatively large, and the wall thickness t2 of the second inner fixing portion 222 is relatively small. Therefore, compared with the first inner fixing portion 212 and the second inner fixing portion 222, the first inner fixing portion 212 has a relatively small material strength and a relatively large wall thickness t1, while the second inner fixing portion 222 has a relatively large material strength and a relatively small wall thickness t2.

[0089] In this way, when the pressure inside the housing 1 is relatively high, the first inner fixing portion 212 with relatively low material strength and relatively large wall thickness t1 can reliably abut against the housing 1 to prevent the first pole 21 from slipping out of the first mounting hole 111, that is, the pressure resistance requirement of the first pole 21 is met, so that the first pole 21 can be reliably connected to the housing 1. At the same time, since the material strength of the second inner fixing portion 222 is greater than the material strength of the first inner fixing portion 212, when the wall thickness t2 of the second inner fixing portion 222 is relatively small compared to the wall thickness t1 of the first inner fixing portion 212, the requirement of reliably abutting the second inner fixing portion 222 against the housing 1 can be met, that is, the pressure resistance requirement of the second pole 22 is met, so that the second pole 22 can be reliably connected to the housing 1. At the same time, since the wall thickness t2 of the second inner fixing portion 222 is thinner than the wall thickness t1 of the first inner fixing portion 212, the material cost of the second inner fixing portion 222 can be reduced.

[0090] As described above, according to the battery cell 102 of the embodiment of the present application, under the premise of satisfying the pressure resistance requirements of the first pole 21 and the second pole 22, respectively, the wall thickness of the second inner fixing part 222 is thinner than the wall thickness of the first inner fixing part 212, thereby reducing the material cost and weight of the second inner fixing part 222. Moreover, since the wall thickness of the second inner fixing part 222 is thinner than the wall thickness of the first inner fixing part 212, the space inside the second inner fixing part 222 can be released, that is, the space occupied by the second inner fixing part 222 in the housing 1 is reduced, and the saved space can be used to increase the injection amount of the electrolyte, or to increase the degree of accommodation of the gas generated during the operation of the battery cell 102, thereby improving the performance of the battery cell 102.

[0091] For the battery cell 102, the pressure inside the shell 1 is relatively high, and the pole 2 is easily squeezed out, especially when the area of ​​the pole 2 is large, the pole 2 has a low pressure resistance level, and is more likely to be squeezed out by the air pressure inside the shell 1. In the embodiment of the present application, by setting the wall thickness of the inner fixing part with weaker material strength to be thicker, the shell improves its pressure resistance level, and the wall thickness of the inner fixing part with stronger material strength is thinner, which can reduce material costs.

[0092] For a battery cell, if the thickness of the inner fixing portion of the pole 2 located on the inner side of the shell 1 is relatively thick, then in the axial direction of the pole 2, it will occupy more height space of the accommodating cavity 10, so that the height of the battery cell assembly 4 in the shell 1 is reduced, affecting the capacity of the battery cell 102. If the first inner fixing portion 212 with relatively weak material strength can meet the pressure resistance level, the second inner fixing portion 222 with relatively strong material strength can also meet the pressure resistance level when it is equal to or less than the wall thickness of the first inner fixing portion 212. Therefore, the capacity of the battery cell 102 can be determined by the wall thickness of the first inner fixing portion 212 with relatively weak material strength. In the embodiment of the present application, by setting the wall thickness of the second inner fixing portion 222 to be smaller than the wall thickness of the first inner fixing portion 212, the material cost and weight of the second pole 22 can be reduced by thinning the second inner fixing portion 222 without affecting the capacity of the battery cell 102 and the pressure resistance level of the second pole 22.

[0093] In some embodiments of the present application, Figure 6 and Figure 8 As shown, the first penetration portion 211 defines a first receiving groove 2111, and the first receiving groove 2111 is open toward the inside or outside of the housing 1, and the first penetration portion 211 includes a first end wall portion 2112 arranged opposite to the opening of the first receiving groove 2111. It can be understood that if the first receiving groove 2111 is open toward the inside of the housing 1, the first end wall portion 2112 is located on the side of the first receiving groove 2111 away from the receiving cavity 10. For example, when the first receiving groove 2111 is open toward the lower side, the first end wall portion 2112 constitutes the top wall of the first receiving groove 2111; and if the first receiving groove 2111 is open toward the outside of the housing 1, the first end wall portion 2112 is located on the side of the first receiving groove 2111 close to the receiving cavity 10. For example, when the first receiving groove 2111 is open toward the upper side, the first end wall portion 2112 constitutes the bottom wall of the first receiving groove 2111. In addition, the first penetration portion 211 can also define two first accommodating grooves 2111 arranged back to back, and one of the two first accommodating grooves 2111 that is relatively close to the accommodating cavity 10 is open toward the inner side of the shell 1, and one of the two first accommodating grooves 2111 that is relatively far from the accommodating cavity 10 is open toward the outer side of the shell 1.

[0094] Thus, since the first receiving groove 2111 is provided on the first penetration portion 211 of the first pole 21, the first pole 21 is hollow, so that the material usage of the first pole 21 can be reduced, and the material cost and weight of the first pole 21 can be reduced while increasing the surface area of ​​the first pole 21. Moreover, it can be understood that the pole 2 is electrically connected between the conductive portion 42 and the current collecting component. When the surface area of ​​the first pole 21 increases, it is beneficial to increase the electrical connection area between the first pole 21 and the first conductive portion 421, thereby facilitating the improvement of the current passing efficiency.

[0095] For example, in combination Figure 8 , the main body material of the first inner fixing part 212 and the first end wall part 2112 is the same, and the wall thickness t3 of the first end wall part 2112 is greater than the wall thickness t1 of the first inner fixing part 212. In this way, since the material strength of the first inner fixing part 212 is relatively weak, the material strength of the first end wall part 2112 is also relatively weak. Since the first end wall part 2112 is opposite to the first receiving groove 2111, by setting the wall thickness t3 of the first end wall part 2112 to be greater than the wall thickness t1 of the first inner fixing part 212, the structural strength and pressure resistance level of the first end wall part 2112 can be improved. For example, the main body material of the first inner fixing part 212 and the first end wall part 2112 are both aluminum. Among them, the "main body material" described in this article can be understood as: when it is composed of only one material, the material is the main body material; when it is an alloy, or composed of multiple materials, the component with the largest content is the main body material.

[0096] Exemplarily, when the axial direction of the first mounting hole 111 is taken as the projection direction, and the plane perpendicular to the axial direction of the first mounting hole 111 is taken as the projection plane, and the orthographic projection area of ​​the first internal fixing portion 212 on the projection plane is smaller than the orthographic projection area of ​​the first end wall portion 2112 on the projection plane, by setting the wall thickness of the first end wall portion 2112 to be larger than the wall thickness of the first internal fixing portion 212, the structural strength of the first end wall portion 2112 with a relatively larger area can be improved.

[0097] In short, by setting the wall thickness of the first end wall portion 2112 (the center of the first pole 21 in short) of the first pole 21 to be greater than the wall thickness of the first inner fixing portion 212 (the edge of the first pole 21 in short), it is equivalent to increasing the wall thickness of the center of the first pole 21 under the premise of meeting the withstand voltage level of the edge of the first pole 21, so that the center of the first pole 21 can show better structural strength in the case of a large area, thereby improving the reliability of the first pole 21. In other words, by setting the wall thickness of the first inner fixing portion 212 (i.e., the edge of the first pole 21) to be less than the wall thickness of the first end wall portion 2112 (i.e., the center of the first pole 21) of the first pole 21, it is equivalent to reducing the wall thickness of the edge of the first pole 21 under the premise of meeting the structural strength of the center of the first pole 21, thereby saving materials, reducing costs and weight, and reducing the height space occupied by the edge of the first pole 21 in the housing 1, thereby improving the capacity of the battery cell 102.

[0098] For example, Figure 8 and Fig. 9 As shown, a first through hole 2114 is formed on the first end wall 2112, which communicates with the inner side of the housing 1 (i.e., the accommodating chamber 10) and the first accommodating groove 2111. The battery cell assembly 4 of the battery cell 102 includes a first conductive portion 421 electrically connected to the first pole 21, the first conductive portion 421 is passed through the first through hole 2114, and includes a first connecting segment 4211 received in the first accommodating groove 2111, the first connecting segment 4211 overlaps the first end wall 2112 and is welded to the first end wall 2112. The welding method is not limited, for example, it can be laser welding, etc.

[0099] Thus, by providing the first through hole 2114, the first conductive portion 421 extends into the first receiving groove 2111, and the first receiving groove 2111 can receive the first conductive portion 421, thereby reducing the height space occupied by the first conductive portion 421 in the receiving cavity 10 and increasing the capacity of the battery cell 102. In addition, when the first receiving groove 2111 is open toward the outside of the housing 1, it is convenient to weld the first connecting section 4211 and the first end wall portion 2112 from the outside of the housing 1, thereby reducing the difficulty of processing.

[0100] In the above technical solution, since the wall thickness of the first end wall portion 2112 of the first pole 21 is greater than the wall thickness of the first internal fixed portion 212, the pressure resistance level of the first pole 21 at the edge is sufficient, and the welding penetration depth between the first connecting section 4211 and the first end wall portion 2112 meets the requirements, which is beneficial to improve the welding connection strength between the first end wall portion 2112 and the first connecting section 4211, thereby improving the reliability and stability of the electrical connection between the first pole 21 and the first conductive portion 421.

[0101] If the thickness of the inner fixing portion of the pole 2 located inside the shell 1 is relatively thick, then in the axial direction of the pole 2, it will occupy more height space of the accommodating cavity 10, so that the height of the battery cell assembly 4 in the shell 1 needs to be reduced, affecting the capacity of the battery cell 102. For the first pole 21 with weaker material strength, by setting the edge and the center of the first pole 21 with unequal thickness, the wall thickness of the first inner fixing portion 212 is set to be smaller than the wall thickness of the first end wall 2112, so that the relatively thick first end wall 2112 can be strengthened to meet the welding penetration and structural strength, and at the same time, the relatively thin first inner fixing portion 212 is thinned relative to the first end wall 2112, and the height space occupied by the accommodating cavity 10 is reduced while meeting the pressure resistance level, the capacity of the battery cell 102 is increased, and the material cost and weight are reduced.

[0102] In some embodiments, Figure 8 and Fig. 9 As shown, the first end wall portion 2112 is arranged relative to the first receiving groove 2111 close to the inner side of the housing 1 (i.e., the receiving chamber 10), and the inner end surface of the first inner fixing portion 212 (i.e., the side surface close to the receiving chamber 10) is flush with the inner end surface of the first end wall portion 2112 (i.e., the side surface close to the receiving chamber 10). For example, the first pole 21 is arranged at the top of the housing 1, the first receiving groove 2111 is open upward, the first end wall portion 2112 constitutes the bottom wall of the first receiving groove 2111, and the lower surface of the first inner fixing portion 212 is flush with the lower surface of the first end wall portion 2112.

[0103] In the above technical solution, by setting the side surface of the first inner fixing portion 212 close to the accommodating cavity 10 to be flush with the side surface of the first end wall portion 2112 close to the accommodating cavity 10, the processing of the first pole 21 can be simplified, the processing difficulty can be reduced, and the production cost can be reduced. Moreover, since the inner end surface of the first end wall portion 2112 does not protrude from the inner end surface of the first inner fixing portion 212 in the direction of the accommodating cavity 10, the height space occupied by the center of the first pole 21 in the shell 1 is reduced, thereby reducing the risk of short circuit between the first pole 21 and the battery cell assembly 4.

[0104] In some embodiments, in combination Figure 8On the premise that the wall thickness t3 of the first end wall portion 2112 is greater than the wall thickness t1 of the first inner fixed portion 212, the first end wall portion 2112 and the first inner fixed portion 212 are both made of aluminum, and the wall thickness t3 of the first end wall portion 2112 can range from 2.2mm to 0.8mm, for example, 2.2mm, 2.0mm, 1.8mm, 1.6mm, 1.4mm, 1.2mm, 1.0mm, 0.8mm, etc., and the wall thickness t1 of the first inner fixed portion 212 can range from 2mm to 0.8mm, for example, 2.0mm, 1.8mm, 1.6mm, 1.4mm, 1.2mm, 1.0mm, 0.8mm, etc.

[0105] Therefore, the wall thickness t3 of the first end wall portion 2112 is not too large, so that the volume of the first accommodating groove 2111 is not too small, which meets the storage requirement of the first conductive part 421. The wall thickness t3 of the first end wall portion 2112 is not too small, so that the first end wall portion 2112 can meet the welding penetration requirement with the first conductive part 421 and the structural strength requirement of the first end wall portion 2112. The wall thickness t1 of the first inner fixed portion 212 is not too large, thereby reducing the height space occupied by the first inner fixed portion 212 in the accommodating cavity 10, increasing the capacity of the battery cell 102, and reducing the material cost and weight. The wall thickness t1 of the first inner fixed portion 212 is not too small, thereby meeting the pressure resistance level of the first pole 21 and improving the problem of the first pole 21 escaping from the shell 1 due to the high pressure in the shell 1.

[0106] Specifically, the wall thickness of the first end wall 2112 and the first inner fixing part 212 can be specifically set and selected according to the system capacity of the battery cell 102. Exemplarily, the wall thickness of the first end wall 2112 is 2.2 mm, and the wall thickness of the first inner fixing part 212 is 2 mm, thereby better meeting the storage requirements for the first conductive part 421, and the first end wall 2112 can meet the welding penetration requirements with the first conductive part 421, as well as the structural strength requirements of the first end wall 2112, and the first inner fixing part 212 occupies less height space of the accommodating cavity 10, thereby increasing the capacity of the battery cell 102, and reducing the material cost and weight, and meeting the pressure resistance level of the first pole 21, and improving the problem that the first pole 21 is detached from the shell 1 due to the high pressure in the shell 1.

[0107] In some embodiments of the present application, Figure 6 and Fig.10As shown, the second penetration portion 221 defines a second receiving groove 2211, and the second receiving groove 2211 is open toward the inside or outside of the housing 1, and the second penetration portion 221 includes a second end wall portion 2212 arranged opposite to the opening of the second receiving groove 2211. It can be understood that if the second receiving groove 2211 is open toward the inside of the housing 1, the second end wall portion 2212 is located on the side of the second receiving groove 2211 away from the receiving cavity 10. For example, when the second receiving groove 2211 is open toward the lower side, the second end wall portion 2212 constitutes the top wall of the second receiving groove 2211; and if the second receiving groove 2211 is open toward the outside of the housing 1, the second end wall portion 2212 is located on the side of the second receiving groove 2211 close to the receiving cavity 10. For example, when the second receiving groove 2211 is open toward the upper side, the second end wall portion 2212 constitutes the bottom wall of the second receiving groove 2211. In addition, the second penetration portion 221 can also define two second accommodating grooves 2211 arranged back to back, and one of the two second accommodating grooves 2211 that is relatively close to the accommodating cavity 10 is open toward the inner side of the shell 1, and one of the two second accommodating grooves 2211 that is relatively far from the accommodating cavity 10 is open toward the outer side of the shell 1.

[0108] Thus, since the second receiving groove 2211 is provided on the second penetration portion 221 of the second pole 22, the second pole 22 is hollow, so that the material usage of the second pole 22 can be reduced, and the material cost and weight of the second pole 22 can be reduced under the premise of increasing the surface area of ​​the second pole 22. Moreover, it can be understood that the pole 2 is electrically connected between the conductive portion 42 and the current collecting component. When the surface area of ​​the second pole 22 is increased, it is beneficial to increase the electrical connection area between the second pole 22 and the second conductive portion 422, thereby facilitating the improvement of the current passing efficiency.

[0109] For example, in combination Fig.10 , the main body material of the second inner fixing portion 222 and the second end wall portion 2212 is the same, and the wall thickness t4 of the second end wall portion 2212 is less than the wall thickness t2 of the second inner fixing portion 222. In this way, since the material strength of the second inner fixing portion 222 is relatively strong, the material strength of the second end wall portion 2212 is also relatively strong. By setting the wall thickness t4 of the second end wall portion 2212 to be less than the wall thickness t2 of the second inner fixing portion 222, the wall thickness of the second inner fixing portion 222 is relatively large to meet the pressure resistance level of the second pole 22, and the wall thickness of the second end wall portion 2212 is relatively small to increase the volume of the second receiving groove 2211, thereby reducing the material cost and weight of the second pole 22. For example, the main body material of the second inner fixing portion 222 and the second end wall portion 2212 are both copper.

[0110] In short, by setting the wall thickness of the second end wall portion 2212 (in short, the center of the second pole 22) of the second pole 22 to be smaller than the wall thickness of the second inner fixing portion 222 (in short, the edge of the second pole 22), it is equivalent to reducing the wall thickness of the center of the second pole 22 with relatively large material strength under the premise of meeting the withstand voltage level at the edge of the second pole 22, and reducing the material cost and weight of the second pole 22 under the premise of meeting the structural strength at the center of the second pole 22, and increasing the volume of the second receiving groove 2211. In other words, by setting the wall thickness of the second inner fixing portion 222 (i.e., the edge of the second pole 22) to be larger than the wall thickness of the second end wall portion 2212 (i.e., the center of the second pole 22), it is equivalent to increasing the wall thickness of the edge of the second pole 22 under the premise of meeting the structural strength at the center of the second pole 22, thereby improving the withstand voltage level of the second pole 22.

[0111] When the first pole 21 and the second pole 22 are arranged on the same side wall of the shell 1, even if the wall thickness of the second inner fixing part 222 is increased, since the wall thickness of the second inner fixing part 222 is smaller than the wall thickness of the first inner fixing part 212, the height space occupied in the shell 1 will not be increased, thereby ensuring the capacity of the battery cell 102.

[0112] For example, Fig.10 and Fig.11 As shown, a second through hole 2214 is formed on the second end wall 2212, which communicates with the inner side of the housing 1 (i.e., the accommodating chamber 10) and the second accommodating groove 2211. The battery cell assembly 4 of the battery cell 102 includes a second conductive portion 422 connected to the second pole 22, the second conductive portion 422 is inserted through the second through hole 2214, and includes a second connecting segment 4221 received in the second accommodating groove 2211, and the second connecting segment 4221 is overlapped on the second end wall 2212 and welded to the second end wall 2212. The welding method is not limited, for example, it can be laser welding.

[0113] Thus, by providing the second through hole 2214, the second conductive portion 422 is extended into the second receiving groove 2211, and the second receiving groove 2211 can receive the second conductive portion 422, thereby reducing the height space occupied by the second conductive portion 422 in the receiving cavity 10 and increasing the capacity of the battery cell 102. In addition, when the second receiving groove 2211 is open toward the outside of the housing 1, it is convenient to weld the second connecting section 4221 and the second end wall portion 2212 from the outside of the housing 1, thereby reducing the difficulty of processing.

[0114] In the above technical solution, since the wall thickness of the second end wall portion 2212 of the second pole 22 is smaller than the wall thickness of the second inner fixing portion 222, the volume of the second accommodating groove 2211 at the center of the second pole 22 can be increased under the premise that the pressure resistance level of the second pole 22 at the edge is sufficient, so as to accommodate the second conductive portion 422 to a greater extent and facilitate the welding of the second connecting section 4221 and the second end wall portion 2212.

[0115] If the thickness of the inner fixing portion of the pole 2 located inside the shell 1 is relatively thick, then in the axial direction of the pole 2, it will occupy more height space of the accommodating cavity 10, so that the height of the battery cell assembly 4 in the shell 1 needs to be reduced, affecting the capacity of the battery cell 102. For the second pole 22 with relatively strong material strength, the capacity of the battery cell 102 can be determined by the first pole 21 with relatively weak material strength. Therefore, by setting the edge and the center of the second pole 22 with unequal thickness, the wall thickness of the second inner fixing portion 222 is set to be greater than the wall thickness of the second end wall 2212 and less than the wall thickness of the first inner fixing portion 212. Therefore, under the premise of ensuring the capacity of the battery cell 102, by thickening the second inner fixing portion 222 relative to the second end wall 2212, the pressure resistance level of the second pole 22 can be improved, and by thinning the second end wall 2212 relative to the second inner fixing portion 222, while ensuring the structural strength of the second end wall 2212, it is beneficial to increase the volume of the second accommodating groove 2211 and reduce the material cost.

[0116] If the second end wall portion 2212 and the second inner fixed portion 222 are of equal thickness and are both relatively thin, during simulated inflation, the second inner fixed portion 222 is equivalent to a cantilever beam, with a large bending moment and obvious deformation. By setting the wall thickness of the second inner fixed portion 222 to be greater than the wall thickness of the second end wall portion 2212, the thickened second fixed portion can be used to improve the pressure resistance level of the second pole 22.

[0117] In some embodiments, Fig.10 and Fig.11 As shown, the second end wall portion 2212 is arranged relative to the second receiving groove 2211 close to the inner side of the housing 1 (i.e., the receiving chamber 10), and the inner end surface of the second inner fixing portion 222 (i.e., the side surface close to the receiving chamber 10) is flush with the inner end surface of the second end wall portion 2212 (i.e., the side surface close to the receiving chamber 10). For example, the second pole 22 is arranged at the top of the housing 1, the second receiving groove 2211 is open upward, the second end wall portion 2212 constitutes the bottom wall of the second receiving groove 2211, and the lower surface of the second inner fixing portion 222 is flush with the lower surface of the second end wall portion 2212.

[0118] In the above technical solution, by setting the side surface of the second inner fixing portion 222 close to the accommodating cavity 10 to be flush with the side surface of the second end wall portion 2212 close to the accommodating cavity 10, the processing of the second pole 22 can be simplified, the processing difficulty can be reduced, and the production cost can be reduced. Moreover, since the inner end surface of the second end wall portion 2212 does not protrude from the inner end surface of the second inner fixing portion 222 in the direction of the accommodating cavity 10, the height space occupied by the center of the second pole 22 in the shell 1 is reduced, thereby reducing the risk of short-circuiting the second pole 22 and the battery cell assembly 4.

[0119] In some embodiments, in combination Fig.10 On the premise that the wall thickness t4 of the second end wall portion 2212 is less than the wall thickness t2 of the second inner fixed portion 222, the second end wall portion 2212 and the second inner fixed portion 222 are both made of copper, and the wall thickness t4 of the second end wall portion 2212 can range from 1.3mm to 0.8mm, for example, 1.3mm, 1.2mm, 1.1mm, 1.0mm, 0.9mm, 0.8mm, etc., and the wall thickness t2 of the second inner fixed portion 222 can range from 1.6mm to 0.8mm, for example, 1.6mm, 1.5mm, 1.4mm, 1.3mm, 1.2mm, 1.1mm, 1.0mm, 0.9mm, 0.8mm, etc.

[0120] Therefore, the wall thickness t4 of the second end wall portion 2212 is not too large, so that the volume of the second accommodating groove 2211 is larger, the storage requirement for the second conductive portion 422 is improved, and the material cost is low. The wall thickness t4 of the second end wall portion 2212 is not too small, so that the second end wall portion 2212 can meet the welding penetration requirement with the second conductive portion 422 and the structural strength requirement of the second end wall portion 2212. The wall thickness t2 of the second inner fixed portion 222 is not too large, thereby reducing the height space occupied by the second inner fixed portion 222 in the accommodating cavity 10, increasing the capacity of the battery cell 102, and reducing the material cost and weight. The wall thickness t2 of the second inner fixed portion 222 is not too small, thereby meeting the pressure resistance level of the second pole 22 and improving the problem of the second pole 22 escaping from the shell 1 due to the high pressure in the shell 1.

[0121] Specifically, the wall thickness of the second end wall 2212 and the second inner fixing portion 222 can be specifically set and selected according to the system capacity of the battery cell 102. Exemplarily, the wall thickness t4 of the second end wall 2212 is 1.2 mm, and the wall thickness t2 of the second inner fixing portion 222 is 1.5 mm, thereby, the storage requirements for the second conductive portion 422 can be better met, and the second end wall 2212 can meet the welding penetration requirements with the second conductive portion 422, as well as the structural strength requirements of the second end wall 2212, and reduce the material cost and weight of the second end wall 2212, and make the second inner fixing portion 222 occupy less height space of the accommodating cavity 10, increase the capacity of the battery cell 102, and reduce the material cost, and meet the pressure resistance level of the second pole 22, and improve the problem that the second pole 22 is detached from the shell 1 due to the high pressure in the shell 1.

[0122] In some embodiments, Figure 7 , Figure 8 and Fig.10 As shown, the first penetration portion 211 defines a first accommodating groove 2111, which is open toward the inner side or the outer side of the shell body 1, and the first penetration portion 211 includes a first end wall portion 2112 arranged opposite to the opening of the first accommodating groove 2111; the second penetration portion 221 defines a second accommodating groove 2211, which is open toward the inner side or the outer side of the shell body 1, and the second penetration portion 221 includes a second end wall portion 2212 arranged opposite to the opening of the second accommodating groove 2211, wherein the relative position relationship between the first accommodating groove 2111 and the first end wall portion 2112 can refer to the above introduction, and the relative position relationship between the second accommodating groove 2211 and the second end wall portion 2212 can refer to the above introduction, and no further details are given here.

[0123] In this embodiment, the material strength of the first end wall portion 2112 is less than that of the second end wall portion 2212, and the wall thickness t3 of the first end wall portion 2112 is greater than the wall thickness t4 of the second end wall portion 2212. In this way, since the material strength of the first end wall portion 2112 is less than that of the second end wall portion 2212, if the first end wall portion 2112 is not easily deformed during the simulated inflation process, the wall thickness of the second end wall portion 2212 is smaller than that of the first end wall portion 2112 and is not easily deformed. Therefore, setting the wall thickness of the second end wall portion 2212 to be smaller than that of the first end wall portion 2112 can effectively increase the volume of the second receiving groove 2211 and reduce the material cost and weight of the second pole 22.

[0124] In some embodiments, Figure 6 and Figure 7As shown, the material strength of the first external fixing portion 213 is less than the material strength of the second external fixing portion 223, and the wall thickness t5 of the first external fixing portion 213 is greater than the wall thickness t6 of the second external fixing portion 223. In this way, since the material strength of the first external fixing portion 213 is less than the material strength of the second external fixing portion 223, when the wall thickness of the first external fixing portion 213 makes the structural strength of the first external fixing portion 213 meet the requirements, the structural strength of the second external fixing portion 223 can also be met by setting the wall thickness of the second external fixing portion 223 smaller than the wall thickness of the first external fixing portion 213. Therefore, by thinning the second external fixing portion 223 relative to the first external fixing portion 213, the material cost and weight of the second pole 22 can be reduced while meeting the structural strength requirements.

[0125] Exemplarily, the second external fixing portion 223 and the first external fixing portion 213 can both be fixed to the shell 1 by riveting, that is, the shape of the first external fixing portion 213 is different before and after riveting. Before riveting, the first external fixing portion 213 is set corresponding to the first mounting hole 111, but after riveting, the first external fixing portion 213 extends in a direction away from the central axis of the first mounting hole 111 and abuts against the outer side of the shell 1. Similarly, the shape of the second external fixing portion 223 is different before and after riveting. Before riveting, the second external fixing portion 223 is set corresponding to the second mounting hole 112, but after riveting, the second external fixing portion 223 extends in a direction away from the central axis of the second mounting hole 112 and abuts against the outer side of the shell 1.

[0126] When the material strength of the first external fixing part 213 is set to be smaller than the material strength of the second external fixing part 223, the wall thickness t5 of the first external fixing part 213 is greater than the wall thickness t6 of the second external fixing part 223, and when the wall thickness of the first external fixing part 213 makes the abutment reliability of the first external fixing part 213 meet the requirements, the abutment reliability of the second external fixing part 223 can also meet the requirements by setting the wall thickness of the second external fixing part 223 to be smaller than the wall thickness of the first external fixing part 213, and at the same time, the material cost and weight of the second pole 22 can be reduced.

[0127] In some embodiments, Figure 4 , Figure 7 , Figure 8 and Fig.10As shown, the housing 1 has a first mounting hole 111 for the first penetration portion 211 to penetrate, the first penetration portion 211 includes a first surrounding wall portion 2113 extending along the circumference of the first mounting hole 111, and a first receiving groove 2111 is formed in the first surrounding wall portion 2113, that is, the first surrounding wall portion 2113 and the first end wall portion 2112 jointly define the first receiving groove 2111. The housing 1 has a second mounting hole 112 for the second penetration portion 221 to penetrate, the second penetration portion 221 includes a second surrounding wall portion 2213 extending along the circumference of the second mounting hole 112, and a second receiving groove 2211 is formed in the second surrounding wall portion 2213, that is, the second surrounding wall portion 2213 and the second end wall portion 2212 jointly define the second receiving groove 2211. The material strength of the first surrounding wall portion 2113 is smaller than the material strength of the second surrounding wall portion 2213 , and the wall thickness t7 of the first surrounding wall portion 2113 is larger than the wall thickness t8 of the second surrounding wall portion 2213 .

[0128] In this way, since the material strength of the first surrounding wall portion 2113 is less than the material strength of the second surrounding wall portion 2213, when the wall thickness of the first surrounding wall portion 2113 makes the structural strength of the first surrounding wall portion 2113 meet the requirements, the structural strength of the second surrounding wall portion 2213 can also meet the requirements by setting the wall thickness of the second surrounding wall portion 2213 to be smaller than the wall thickness of the first surrounding wall portion 2113. Therefore, by thinning the second surrounding wall portion 2213 relative to the first surrounding wall portion 2113, the material cost and weight of the second pole 22 can be reduced while meeting the structural strength requirements, and the volume of the second accommodating groove 2211 can be increased, as well as the area of ​​the second end wall portion 2212, which is beneficial to increase the welding area between the second end wall portion 2212 and the second conductive portion 422, thereby improving the current carrying capacity.

[0129] In some embodiments, the first pole 21 is an integral part with the same main body material at all locations, and the second pole 22 is an integral part with the same main body material at all locations, and the material strength of the second pole 22 is greater than the material strength of the first pole 21. The processing difficulty and manufacturing cost of the first pole 21 can be reduced, the processing difficulty and manufacturing cost of the second pole 22 can be reduced, and it can be easily achieved that the material strength of the second pole 22 at all locations is greater than the material strength of the first pole 21 at all locations, so that the wall thickness of the second pole 22 can be reduced to a greater extent, which is more conducive to reducing the material cost and weight of the second pole 22.

[0130] Exemplarily, the first pole 21 is a positive pole, and the main material of the first pole 21 is aluminum, and the second pole 22 is a negative pole, and the main material of the second pole 22 is copper. That is, the main material of the positive pole can be aluminum, and the main material of the negative pole can be copper. Since the material strength of aluminum is lower than that of copper, or in other words, the material strength of copper is higher than that of aluminum, the requirement that the material strength of the negative pole is greater than that of the positive pole can be met, which is conducive to reducing the material cost and weight of the negative pole.

[0131] For example, when the first pole 21 is a positive pole, the main material of the first pole 21 is aluminum, and the second pole 22 is a negative pole, the main material of the second pole 22 is copper, during the simulation of inflation, the first end wall portion 2112 of the positive pole with weaker material strength corresponds to the first accommodating groove 2111, and the thickness of the first end wall portion 2112 cannot be too small, and the penetration depth of the welding between the first end wall portion 2112 and the first conductive portion 421 needs to be large to meet the welding requirements, but the material strength of the negative pole is relatively strong. The strength is relatively strong, and the second end wall portion 2212 of the negative electrode column is not easy to deform even if the wall thickness is smaller than the wall thickness of the first end wall portion 2112 of the positive electrode column, and the second end wall portion 2212 can also meet the welding requirements with the second conductive portion 422. In addition, the thickness of the first internal fixed portion 212 of the positive electrode column with weaker material strength needs to be larger to meet the voltage resistance level. Therefore, the thickness of the first internal fixed portion 212 will directly determine the capacity of the battery cell 102, so the thickness of the first internal fixed portion 212 cannot be too large. Based on the above considerations, some embodiments of the present application set the wall thickness of the first end wall portion 2112 of the positive electrode column to be greater than the wall thickness of the first internal fixed portion 212, thereby reducing the deformation of the first end wall portion 2112 and increasing the welding depth between the first end wall portion 2112 and the first conductive portion 421, and reducing the thickness of the first internal fixed portion 212 to increase the capacity of the battery cell 102 and reduce the cost. Moreover, by setting the wall thickness of the second end wall portion 2212 of the negative electrode column to be smaller than the wall thickness of the second internal fixed portion 222, and the wall thickness of the second internal fixed portion 222 is smaller than the wall thickness of the first internal fixed portion 212, the material cost and weight of the second electrode column 22 can be reduced and the volume of the second accommodating groove 2211 can be increased while ensuring the structural strength and pressure resistance level of the second electrode column 22.

[0132] In some embodiments, Figure 8 and Fig.10 As shown, a first pole cover plate 51 is welded to the outside of the first pole 21, the first pole cover plate 51 is an aluminum cover plate and is suitable for welding with a busbar component, a second pole cover plate 52 is welded to the outside of the second pole 22, the second pole cover plate 52 is a copper-aluminum composite cover plate and is welded to the second pole 22 through a copper portion 521, and the aluminum portion 522 of the second pole cover plate 52 is suitable for welding with a busbar component.

[0133] In the above technical solution, the first pole cover plate 51 and the first pole 21 can be welded with aluminum and aluminum, which is conducive to the welding of the first pole cover plate 51 and the first pole 21, and the second pole cover plate 52 and the second pole 22 can be welded with copper and copper, which is conducive to the welding of the second pole cover plate 52 and the second pole 22, and the busbar component is usually made of aluminum, so the first pole cover plate 51 and the busbar component can be welded with aluminum and aluminum, which is conducive to the welding of the first pole cover plate 51 and the busbar component, and the second pole cover plate 52 and the busbar component can also be welded with aluminum and aluminum, which is conducive to the welding of the second pole cover plate 52 and the busbar component.

[0134] In some embodiments, Figure 3-Figure 5 As shown, the shell 1 includes a first shell wall 11, and the first pole 21 and the second pole 22 are both arranged on the first shell wall 11. In this way, the processing can be simplified, the processing difficulty can be reduced, and the processing efficiency can be improved. In addition, the axial directions of the first pole 21 and the second pole 22 are consistent with the height direction of the battery cell 102, and the first internal fixing portion 212 and the second internal fixing portion 222 both occupy the height space on the same side of the shell 1. The height space occupied by the two has an overlapping part. Compared with arranging the first pole 21 and the second pole 22 on opposite sides respectively, the occupation of the height space in the shell 1 can be reduced, which is conducive to increasing the capacity of the battery.

[0135] According to the second aspect of the present application, the present application also provides a battery 100, including a battery cell 102 of any of the above solutions. It is worth noting that the battery 100 according to the embodiment of the present application may include a box body 101, or may not include a box body 101. Therefore, since the reliability of the battery cell 102 according to the embodiment of the present application is improved and the cost is reduced, it is beneficial to improve the performance of the battery 100 and reduce the cost of the battery 100.

[0136] Exemplarily, the battery may further include a busbar component, and the battery cells 102 are multiple and at least two are electrically connected through the busbar component. Thus, multiple battery cells 102 can be connected in series and / or in parallel. For example, when multiple battery cells 102 are connected in series, the pole cover of the anode of one battery cell 102 is connected to the pole cover of the cathode of the next battery cell 102 through a busbar component, and the pole cover of the cathode of the battery cell 102 is connected to the pole cover of the anode of the previous battery cell 102 through another busbar component.

[0137] According to the third aspect of the present application, the present application also provides an electric device, including the battery 100 of any of the above solutions, and the battery 100 is used to provide electric energy for the electric device. The electric device can be any of the above-mentioned devices or systems using the battery, such as a vehicle 1000. Since the performance of the battery 100 is improved, it is beneficial to improve the working power performance of the electric device, and since the cost of the battery 100 is reduced, it is beneficial to reduce the cost of the electric device.

[0138] Next, a battery cell 102 according to a specific embodiment of the present application is described.

[0139] The battery cell 102 includes a shell 1, a first pole 21 and a second pole 22. The shell 1 includes a first shell wall 11. The first pole 21 and the second pole 22 are both arranged on the first shell wall 11. The first pole 21 is a positive pole made of aluminum, and the second pole 22 is a negative pole made of copper. In addition, a pressure relief structure 7 located between the first pole 21 and the second pole 22 is also provided on the first shell wall 11. A sealed insulating assembly 3 is respectively provided between the first pole 21, the second pole 22 and the first shell wall 11. The sealed insulating assembly 3 includes: a first insulating member 31 located on the inner side of the first shell wall 11, a second insulating member 32 located on the outer side of the first shell wall 11, and a sealing ring 33 located on the inner side of the first shell wall 11.

[0140] The first pole 21 includes a first penetration portion 211 penetrated through the housing 1, and a first inner fixing portion 212 and a first outer fixing portion 213 connected to the first penetration portion 211 and respectively disposed on the inner and outer sides of the housing 1. The housing 1 has a first mounting hole 111 for the first penetration portion 211 to penetrate, the first penetration portion 211 includes a first surrounding wall portion 2113 extending along the circumference of the first mounting hole 111, the first penetration portion 211 includes a first end wall portion 2112 disposed on the first surrounding wall portion 2113 and close to the inner side of the housing 1, and a first receiving groove 2111 opened toward the outer side of the housing 1 is formed between the first surrounding wall portion 2113 and the first end wall portion 2112.

[0141] The second pole 22 includes a second penetration portion 221 penetrated through the housing 1, and a second inner fixing portion 222 and a second outer fixing portion 223 connected to the second penetration portion 221 and respectively disposed on the inner and outer sides of the housing 1. The housing 1 has a second mounting hole 112 for the second penetration portion 221 to penetrate, the second penetration portion 221 includes a second surrounding wall portion 2213 extending along the circumference of the second mounting hole 112, the second penetration portion 221 includes a second end wall portion 2212 disposed on the second surrounding wall portion 2213 and close to the inner side of the housing 1, and a second receiving groove 2211 open toward the outer side of the housing 1 is formed between the second surrounding wall portion 2213 and the second end wall portion 2212.

[0142] The wall thickness t1 of the first inner fixed portion 212 is greater than the wall thickness t2 of the second inner fixed portion 222 (i.e., t1>t2), the wall thickness t3 of the first end wall portion 2112 is greater than the wall thickness t1 of the first inner fixed portion 212 (i.e., t3>t1), the wall thickness t4 of the second end wall portion 2212 is less than the wall thickness t2 of the second inner fixed portion 222 (i.e., t2>t4), the wall thickness t3 of the first end wall portion 2112 is greater than the wall thickness t4 of the second end wall portion 2212 (i.e., t3>t4), i.e., t3>t1>t2>t4.

[0143] During the simulated inflation process, the first end wall portion 2112 of the positive electrode column with weaker material strength is easily deformed at the corresponding first accommodating groove 2111, the thickness of the first end wall portion 2112 cannot be too small, and the welding depth of the first end wall portion 2112 and the first conductive portion 421 needs to be larger to meet the welding requirements, but the material strength of the negative electrode column is stronger, and the wall thickness of the second end wall portion 2212 of the negative electrode column is not easy to deform even if it is smaller than the wall thickness of the first end wall portion 2112 of the positive electrode column, and the second end wall portion 2212 can also meet the welding requirements with the second conductive portion 422. In addition, the thickness of the first inner fixed portion 212 of the positive electrode column with weaker material strength needs to be larger to meet the pressure resistance level, so the thickness of the first inner fixed portion 212 will directly determine the capacity of the battery cell 102, and the thickness of the first inner fixed portion 212 cannot be too large. Based on the above considerations, some embodiments of the present application set the wall thickness of the first end wall portion 2112 of the positive electrode column to be greater than the wall thickness of the first internal fixed portion 212, thereby reducing the deformation of the first end wall portion 2112 and increasing the welding depth between the first end wall portion 2112 and the first conductive portion 421, and reducing the thickness of the first internal fixed portion 212 to increase the capacity of the battery cell 102 and reduce the cost. Moreover, by setting the wall thickness of the second end wall portion 2212 of the negative electrode column to be smaller than the wall thickness of the second internal fixed portion 222, and the wall thickness of the second internal fixed portion 222 is smaller than the wall thickness of the first internal fixed portion 212, the material cost and weight of the second electrode column 22 can be reduced and the volume of the second accommodating groove 2211 can be increased while ensuring the structural strength and pressure resistance level of the second electrode column 22.

[0144] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

[0145] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A battery cell, characterized in that: include: case; A first pole, comprising a first penetration portion penetrated through the shell, and a first inner fixing portion and a first outer fixing portion connected to the first penetration portion and respectively disposed on inner and outer sides of the shell; A second pole, comprising a second penetration portion penetrated through the shell, and a second inner fixing portion and a second outer fixing portion connected to the second penetration portion and respectively disposed on inner and outer sides of the shell; The material strength of the first inner fixing portion is smaller than the material strength of the second inner fixing portion, and the wall thickness of the first inner fixing portion is larger than the wall thickness of the second inner fixing portion.

2. The battery cell according to claim 1, characterized in that: The first penetration portion defines a first accommodating groove, which is open toward the inner side or the outer side of the shell. The first penetration portion includes a first end wall portion arranged opposite to the opening of the first accommodating groove. The first internal fixing portion is made of the same main body material as the first end wall portion, and the wall thickness of the first end wall portion is greater than the wall thickness of the first internal fixing portion.

3. The battery cell according to claim 2, characterized in that: A first through hole connecting the inner side of the shell and the first receiving groove is formed on the first end wall portion, and the battery cell assembly of the battery cell includes a first conductive portion electrically connected to the first pole, the first conductive portion is passed through the first through hole, and includes a first connecting section received in the first receiving groove, the first connecting section is overlapped on the first end wall portion and welded to the first end wall portion.

4. The battery cell according to claim 2 or 3, characterized in that: The first end wall portion is arranged relative to the first accommodating groove and close to the inner side of the shell, and the inner end surface of the first inner fixing portion is flush with the inner end surface of the first end wall portion.

5. The battery cell according to any one of claims 2 to 4, characterized in that: The first end wall portion is made of aluminum and has a wall thickness of 2.2 mm to 0.8 mm, and the first inner fixing portion has a wall thickness of 2 mm to 0.8 mm.

6. The battery cell according to claim 5, characterized in that: The wall thickness of the first end wall portion is 2.2 mm, and the wall thickness of the first inner fixing portion is 2 mm.

7. The battery cell according to any one of claims 1 to 6, characterized in that: The second penetration portion defines a second accommodating groove, which is open toward the inner side or the outer side of the shell. The second penetration portion includes a second end wall portion arranged opposite to the opening of the second accommodating groove. The second internal fixing portion is made of the same main material as the second end wall portion, and the wall thickness of the second end wall portion is smaller than the wall thickness of the second internal fixing portion.

8. The battery cell according to claim 7, characterized in that: A second through hole connecting the inner side of the shell and the second receiving groove is formed on the second end wall portion, and the battery cell assembly of the battery cell includes a second conductive portion connected to the second pole, the second conductive portion is passed through the second through hole, and includes a second connecting section received in the second receiving groove, and the second connecting section is overlapped on the second end wall portion and welded to the second end wall portion.

9. The battery cell according to claim 7 or 8, characterized in that: The second end wall portion is arranged relative to the second accommodating groove and close to the inner side of the shell, and the inner end surface of the second inner fixing portion is flush with the inner end surface of the second end wall portion.

10. The battery cell according to any one of claims 7 to 9, characterized in that: The second end wall portion is made of copper and has a wall thickness of 1.3 mm to 0.8 mm, and the second inner fixing portion has a wall thickness of 1.6 mm to 0.8 mm.

11. The battery cell according to claim 10, characterized in that: The wall thickness of the second end wall portion is 1.2 mm, and the wall thickness of the second inner fixing portion is 1.5 mm.

12. The battery cell according to any one of claims 1 to 11, characterized in that: The first penetration portion defines a first accommodating groove, which is open toward the inner side or the outer side of the shell, and the first penetration portion includes a first end wall portion arranged opposite to the opening of the first accommodating groove. The second penetration portion defines a second accommodating groove, which is open toward the inner side or the outer side of the shell, and the second penetration portion includes a second end wall portion arranged opposite to the opening of the second accommodating groove, wherein the material strength of the first end wall portion is less than the material strength of the second end wall portion, and the wall thickness of the first end wall portion is greater than the wall thickness of the second end wall portion.

13. The battery cell according to any one of claims 1 to 12, characterized in that: The material strength of the first external fixing portion is smaller than the material strength of the second external fixing portion, and the wall thickness of the first external fixing portion is larger than the wall thickness of the second external fixing portion.

14. The battery cell according to any one of claims 1 to 13, characterized in that: The shell has a first mounting hole for the first penetration portion to penetrate, the first penetration portion includes a first surrounding wall portion extending along the circumference of the first mounting hole, and a first accommodating groove is formed in the first surrounding wall portion; the shell has a second mounting hole for the second penetration portion to penetrate, the second penetration portion includes a second surrounding wall portion extending along the circumference of the second mounting hole, and a second accommodating groove is formed in the second surrounding wall portion; wherein, the material strength of the first surrounding wall portion is less than the material strength of the second surrounding wall portion, and the wall thickness of the first surrounding wall portion is greater than the wall thickness of the second surrounding wall portion.

15. The battery cell according to any one of claims 1 to 14, characterized in that: The first pole is an integral part with the same main body material at all locations, and the second pole is an integral part with the same main body material at all locations, and the material strength of the second pole is greater than the material strength of the first pole.

16. The battery cell according to claim 15, characterized in that: The first pole is a positive pole, and a main material of the first pole is aluminum. The second pole is a negative pole, and a main material of the second pole is copper.

17. The battery cell according to claim 16, characterized in that: A first pole cover is welded to the outside of the first pole, the first pole cover is an aluminum cover and is suitable for welding to a busbar component, a second pole cover is welded to the outside of the second pole, the second pole cover is a copper-aluminum composite cover and is welded to the second pole through a copper portion, and the aluminum portion of the second pole cover is suitable for welding to a busbar component.

18. The battery cell according to any one of claims 1 to 17, characterized in that: The shell includes a first shell wall, and the first pole and the second pole are both arranged on the first shell wall.

19. A battery, characterized in that: The invention comprises a battery cell according to any one of claims 1 to 18.

20. An electrical device, characterized in that: Comprising a battery according to claim 19.

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