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. The battery monomer comprises a shell and an end cover, a containing cavity is formed in the shell and used for containing the electrode assembly, an opening is formed in one end, in the first direction, of the shell, and the opening communicates with the containing cavity. The end cover covers the opening and is provided with a connecting part inserted into the containing cavity in the first direction. One of the cavity wall surface of the accommodating cavity and the peripheral surface of the connecting part is provided with a clamping groove, and the other one is convexly provided with a clamping bulge which is clamped in the clamping groove. According to the battery monomer, on one hand, the assembly between the end cover and the shell is conveniently realized, the assembly difficulty between the end cover and the shell is favorably reduced, and on the other hand, the end cover can be prevented from being separated from the shell along the first direction through the clamping matching of the clamping bulge and the clamping groove, so that the connection reliability and the structural strength between the end cover and the shell can be improved; therefore, the phenomenon of connection failure of the end cover and the shell in the use process of the single battery is 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. With the vigorous promotion of new energy vehicles, the demand for power battery products is also growing. Among them, batteries, as core components of new energy vehicles, have high requirements in terms of reliability and service life.

[0003] In battery technology, the outer shell of a battery cell usually includes a shell and an end cap, wherein the shell is used to accommodate the electrode assembly, and the end cap is covered on the shell, so that the shell and the end cap together form a closed space for accommodating the electrode assembly. However, due to the complex use environment of the battery, the connection between the end cap and the shell of the existing battery cell is prone to failure during use, resulting in the risk of leakage of the battery cell, which is not conducive to improving the service life and reliability of the battery cell. Utility Model Content

[0004] The embodiments of the present application provide a battery cell, a battery, and an electrical device, which can effectively improve the service life and reliability of the battery cell.

[0005] In a first aspect, an embodiment of the present application provides a battery cell, comprising a shell and an end cover; a accommodating cavity is formed inside the shell, the accommodating cavity is used to accommodate an electrode assembly, and an opening is formed at one end of the shell in a first direction, the opening is connected to the accommodating cavity; the end cover covers the opening, and the end cover has a connecting portion inserted into the accommodating cavity along the first direction; wherein one of the cavity wall surface of the accommodating cavity and the outer peripheral surface of the connecting portion is provided with a snap-fit ​​groove, and the other is convexly provided with a snap-fit ​​protrusion, and the snap-fit ​​protrusion is snapped into the snap-fit ​​groove.

[0006] In the above technical scheme, the battery cell is provided with a shell and an end cover, the end cover is covered at the opening of the shell, and the end cover has a connecting portion inserted into the accommodating cavity along a first direction, and a snap groove is provided on one of the cavity wall surface of the accommodating cavity and the outer peripheral surface of the connecting portion, and a snap protrusion is convexly provided on the other, so that the snap protrusion can be snapped into the snap groove after the end cover and the shell are assembled with each other. On the one hand, the battery cell adopting this structure is convenient for assembling the end cover and the shell, which is conducive to reducing the difficulty of assembling the end cover and the shell, thereby effectively improving the production efficiency of the battery cell. On the other hand, the snap-fitting of the snap protrusion and the snap groove can limit the end cover from detaching from the shell along the first direction, thereby improving the connection reliability and structural strength between the end cover and the shell, so as to reduce the phenomenon of failure of the connection between the end cover and the shell during use of the battery cell, thereby effectively reducing the risk of leakage of the battery cell, and helping to improve the reliability and service life of the battery cell.

[0007] In some embodiments, the snap-in groove is provided on the outer peripheral surface of the connecting portion, and the snap-in protrusion is convexly provided on the cavity wall surface of the accommodating cavity.

[0008] In the above technical solution, by arranging the snap-fit ​​groove on the outer peripheral surface of the connecting portion and correspondingly arranging the snap-fitting protrusion on the cavity wall surface of the accommodating cavity of the shell, the snap-fitting protrusion can be snapped into the snap-fit ​​groove when the connecting portion of the end cover is inserted into the accommodating cavity from the opening along the first direction. The battery cell adopting this structure can reduce the difficulty of respectively arranging the snap-fitting groove and the snap-fitting protrusion on the end cover and the shell, and there is no need to increase the wall thickness of the shell by arranging the snap-fitting groove on the shell, which is beneficial to reduce the manufacturing difficulty and manufacturing cost of the battery cell.

[0009] In some embodiments, a groove is provided on the outer peripheral surface of the shell and corresponds to the position of the locking protrusion.

[0010] In the above technical solution, a groove is provided on the outer circumferential surface of the shell at a position corresponding to the latching protrusion, so that a groove is formed on the side of the shell away from the latching protrusion and in an area corresponding to the latching protrusion, so that a groove can be formed on the outer circumferential surface of the shell by a processing technique such as rolling or stamping, and a latching protrusion can be formed on the cavity wall surface of the accommodating cavity of the shell at a position corresponding to the groove, which is conducive to reducing the difficulty of setting the latching protrusion on the shell, so as to improve the production efficiency of the battery cell.

[0011] In some embodiments, the engaging groove is an annular groove extending along the circumference of the connecting portion.

[0012] In the above technical solution, by setting the snap-in groove as an annular groove structure arranged around the circumference of the connecting part, the snap-in groove can be used for snapping in any position of the snap-in protrusion when the connecting part of the end cover is inserted into the accommodating cavity, and the snap-in cooperation between the snap-in protrusion and the snap-in groove can be achieved without positioning and matching the snap-in protrusion and the snap-in groove, so that the assembly between the end cover and the shell can be achieved without rotating and adjusting the end cover when the end cover and the shell are assembled with each other, which is beneficial to reducing the difficulty of assembly between the end cover and the shell, and can improve the assembly efficiency between the end cover and the shell.

[0013] In some embodiments, the latching protrusion is an annular structure extending along the circumference of the connecting portion.

[0014] In the above technical solution, by setting the latching protrusion as an annular structure arranged around the circumference of the connecting part, the latching protrusion can match with the snap-fitting groove of the annular structure. On the one hand, it is convenient for the latching protrusion and the snap-fitting groove to engage with each other, which is beneficial to reduce the difficulty of assembly between the end cover and the shell. On the other hand, it can further improve the connection stability and reliability between the end cover and the shell, so as to reduce the phenomenon of connection failure between the end cover and the shell during the use of the battery cell, and can improve the balance of mutual force constraints between the end cover and the shell.

[0015] In some embodiments, a cross section of an outer surface of a portion of the latching protrusion that is latched in the latching groove is arc-shaped, and the cross section is perpendicular to an extending direction of the latching protrusion.

[0016] In the above technical solution, the cross-section of the outer surface of the part of the card protrusion that is engaged in the engaging groove is set to an arc shape perpendicular to the extension direction of the card protrusion, so that the outer surface of the part of the card protrusion that is engaged in the engaging groove is a smooth arc surface, so that when the connecting part of the end cover is inserted into the accommodating cavity along the first direction, the card protrusion is convenient for being engaged in the engaging groove under the guidance of its outer surface, which is beneficial to improving the smoothness of the engaging of the card protrusion into the engaging groove, so as to reduce the difficulty of the card protrusion being engaged in the engaging groove, and can reduce the phenomenon of mutual locking between the connecting part of the end cover and the shell.

[0017] In some embodiments, a groove wall surface of the engaging groove matches an outer surface of a portion of the engaging protrusion engaged in the engaging groove.

[0018] In the above technical solution, by setting the groove wall surface of the snap-in groove to a structure that fits with the outer surface of the part of the snap-in protrusion located in the snap-in groove, the shape of the snap-in groove is the same as the shape of the part of the snap-in protrusion that is snapped in the snap-in groove. On the one hand, the smoothness of the snap-in protrusion being snapped into the snap-in groove can be further improved to reduce the difficulty of the snap-in protrusion being snapped into the snap-in groove. On the other hand, the structural stability of the mutual snapping of the snap-in protrusion and the snap-in groove can be improved to improve the reliability of the connection between the end cover and the shell, thereby further reducing the risk of failure of the connection between the end cover and the shell during use of the battery cell.

[0019] In some embodiments, there are a plurality of the latching protrusions, and the plurality of the latching protrusions are arranged at intervals along the first direction, and the latching protrusions and the latching grooves are arranged in a one-to-one correspondence.

[0020] In the above technical solution, by providing a plurality of latching protrusions, the plurality of latching protrusions are arranged at intervals along the first direction, and the latching grooves correspond to the latching protrusions one by one, so that there are also a plurality of latching grooves, the plurality of latching grooves are arranged at intervals along the first direction, and each latching protrusion is latched in a latching groove, the battery cell adopting this structure can further improve the ability of the latching protrusion and the latching groove to cooperate to limit the end cover from separating from the shell along the first direction, thereby further improving the connection reliability and structural strength between the end cover and the shell, so as to further reduce the phenomenon of failure of the connection between the end cover and the shell during the use of the battery cell, and further reduce the risk of leakage of the battery cell, so as to improve the reliability and service life of the battery cell.

[0021] In some embodiments, along the first direction, the shell has a first end and a second end opposite to each other, the opening is arranged at the first end, and along the direction pointing from the first end to the second end, the sizes of the plurality of protrusions protruding in the radial direction of the connecting portion gradually increase.

[0022] In the above technical solution, among the multiple latching protrusions arranged at intervals along the first direction, the radial dimensions of the multiple latching protrusions gradually increase in the direction from the first end of the shell to the second end of the shell, that is, the latching protrusion closest to the opening in the first direction among the multiple latching protrusions has the smallest radial protrusion size in the connecting portion, while the latching protrusion farthest from the opening in the first direction has the largest radial protrusion size in the connecting portion, which is conducive to reducing the difficulty of inserting the end cover from the opening into the accommodating cavity along the first direction, and can reduce the difficulty of respectively engaging the multiple latching protrusions with the multiple engaging grooves, so as to reduce the difficulty of assembling the end cover and the shell.

[0023] In some embodiments, along the first direction, a avoidance groove is formed on a side of the connecting portion facing the accommodating cavity.

[0024] In the above technical solution, an avoidance groove is provided on the side of the connecting portion facing the accommodating cavity along the first direction. On the one hand, the avoidance groove can avoid other components inside the battery cell, which is beneficial to improving the internal space utilization of the battery cell, so as to improve the energy density of the battery cell. On the other hand, it can effectively improve the ability of the connecting portion to undergo elastic deformation along its radial direction, so that the connecting portion can be elastically deformed during the process of being inserted into the accommodating cavity, so that the cam can be snapped into the snap-in groove, thereby reducing the difficulty of assembly between the end cover and the shell.

[0025] In some embodiments, a radial dimension of the avoidance groove gradually increases from a groove bottom surface of the avoidance groove to a groove opening of the avoidance groove.

[0026] In the above technical solution, by setting the avoidance groove as a structure in which the radial dimension gradually increases from the bottom surface of the avoidance groove to the notch of the avoidance groove, the groove side of the avoidance groove is an outwardly inclined slope or arc surface, which can reduce the collision between the connecting part and other components inside the battery cell on the one hand, and on the other hand, make the end of the connecting part close to the notch of the avoidance groove in the first direction more capable of elastic deformation, so that it can further facilitate the elastic deformation of the connecting part during the insertion process of the accommodating cavity so that the cam is inserted into the snap-in groove, so as to further reduce the difficulty of assembly between the end cover and the shell.

[0027] In some embodiments, the outer peripheral surface of the connecting portion abuts against the cavity wall surface of the accommodating cavity.

[0028] In the above technical solution, the outer peripheral surface of the connecting portion of the end cover and the cavity wall surface of the accommodating cavity of the shell are arranged to abut against each other to reduce the gap size between the shell and the connecting portion, thereby alleviating the phenomenon of accidental disengagement of the latching protrusion and the latching groove, further improving the latching effect between the latching protrusion and the latching groove, and thus effectively improving the connection reliability and structural strength between the end cover and the shell, which is beneficial to reducing the phenomenon of connection failure between the end cover and the shell during use of the battery cell.

[0029] In some embodiments, the battery cell further includes a sealant; the sealant is disposed between the latch protrusion and a groove wall surface of the latch groove, and the sealant is configured to seal a gap between the latch protrusion and the groove wall surface of the latch groove.

[0030] In the above technical solution, a seal is also provided between the latch protrusion and the groove wall of the latch groove, and the seal can seal the gap between the latch protrusion and the groove wall of the latch groove, thereby improving the sealing effect between the end cover and the shell to reduce the risk of leakage of the battery cell.

[0031] In some embodiments, the sealing member is a sealant disposed between the latch protrusion and the groove wall surface of the latch groove.

[0032] In the above technical solution, the seal is a sealant arranged between the protrusion and the groove wall of the snap-fit ​​groove. The seal with this structure can better fill the gap between the protrusion and the groove wall of the snap-fit ​​groove to improve the sealing effect between the end cover and the shell.

[0033] In some embodiments, an overflow glue space is formed between the cavity wall of the accommodating cavity and the outer peripheral surface of the connecting portion. Along the first direction, the overflow glue space is located on at least one side of the latch protrusion, and the overflow glue space is configured to accommodate sealant overflowing between the latch protrusion and the groove wall of the snap-in groove.

[0034] In the above technical solution, an overflow glue space is also formed between the cavity wall surface of the accommodating cavity and the outer peripheral surface of the connecting portion, and the overflow glue space is arranged on at least one side of the latching protrusion in the first direction, so that the overflow glue space can accommodate excess and overflowed sealant between the latching protrusion and the groove wall surface of the latching groove when the latching protrusion is latched in the latching groove. On the one hand, the battery cell adopting this structure does not need to further process the overflowed sealant, which is beneficial to improving the assembly efficiency of the battery cell. On the other hand, surplus sealant can be arranged between the latching protrusion and the groove wall surface of the latching groove to improve the sealing effect between the latching protrusion and the groove wall surface of the latching groove.

[0035] In some embodiments, the sealing member is a sealing ring disposed between the latching protrusion and a groove wall surface of the latching groove.

[0036] In the above technical solution, the seal is a sealing ring arranged between the latch protrusion and the groove wall of the latch groove. The seal with this structure is convenient for arranging the seal between the latch protrusion and the groove wall of the latch groove, which is beneficial to reduce the difficulty of assembling the seal, thereby improving the assembly efficiency of the battery cell.

[0037] In some embodiments, the end cover also includes a cover body; along the first direction, the cover body abuts against one end of the shell provided with the opening, and the cover body covers the opening, and the connecting portion protrudes from the side of the cover body facing the accommodating cavity.

[0038] In the above technical solution, the end cover also includes a cover body, the connecting portion is protruding on the side of the cover body facing the accommodating cavity, and the cover body abuts against one end of the shell provided with an opening along a first direction and covers the opening. The end cover adopting such a structure can, on the one hand, play a certain limiting and positioning role on the end cover through the structure in which the cover body and the shell abut each other, so as to reduce the phenomenon that the connecting portion of the end cover is over-inserted into the accommodating cavity, and on the other hand, can further enhance the effect of the end cover covering the opening of the shell, so as to enhance the connection reliability and stability between the end cover and the shell.

[0039] In some embodiments, the battery cell is cylindrical, and a central axis of the battery cell extends along the first direction.

[0040] In the above technical solution, by setting the battery cell to a cylindrical shape, it is convenient to process and form a battery cell with a cylindrical structure. On the one hand, the battery cell has the advantages of high capacity, long cycle life, and a wide range of operating environment temperature. On the other hand, it is convenient to insert the connecting portion of the end cover into the accommodating cavity along the first direction, and can further reduce the difficulty of assembling the mutual engagement of the clamping protrusion and the clamping groove, which is beneficial to reduce the manufacturing difficulty of the battery cell and improve the production efficiency of the battery cell.

[0041] In a second aspect, an embodiment of the present application further provides a battery, comprising the above-mentioned battery cell.

[0042] In a third aspect, an embodiment of the present application further provides an electrical device, comprising the above-mentioned battery cell, wherein the battery cell is used to provide electrical energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] 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.

[0044] Figure 1 A schematic diagram of the structure of a vehicle provided in some embodiments of the present application;

[0045] Figure 2 An exploded view of the structure of a battery provided in some embodiments of the present application;

[0046] Figure 3 A schematic diagram of the structure of a battery cell provided in some embodiments of the present application;

[0047] Figure 4 A cross-sectional view of a battery cell provided for some embodiments of the present application;

[0048] Figure 5 for Figure 4 A partial enlarged view of the battery cell at A shown;

[0049] Figure 6 An isometric view of a battery cell provided for some embodiments of the present application.

[0050] Icons: 1000-vehicle; 100-battery; 10-box; 11-first box body; 12-second box body; 20-battery cell; 21-shell; 211-accommodating chamber; 212-opening; 213-clamping protrusion; 214-first end; 215-second end; 216-groove; 22-end cover; 221-connecting part; 2211-clamping groove; 2212-avoidance groove; 222-cover body; 2221-sinking groove; 23-electrode assembly; 231-ear; 24-electrode terminal; 25-pressure relief mechanism; 26-seal; 27-overflow glue space; 200-controller; 300-motor; X-first direction. DETAILED DESCRIPTION

[0051] 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.

[0052] 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.

[0053] 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.

[0054] 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 the internal communication 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.

[0055] 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.

[0056] 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.

[0057] The term "plurality" used in the present application refers to two or more (including two).

[0058] In the embodiment of the present application, the battery cell may be a secondary battery. A secondary battery refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0059] The battery cell can be a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel hydrogen battery, a nickel cadmium battery, a lead storage battery, etc., which is not limited in the embodiments of the present application.

[0060] A battery cell generally includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charge and discharge process of the battery cell, active ions (such as lithium ions) are embedded and removed between the positive electrode and the negative electrode. The separator is set between the positive electrode and the negative electrode to prevent the positive and negative electrodes from short-circuiting, while allowing active ions to pass through.

[0061] In some embodiments, the positive electrode may be a positive electrode sheet, and the positive electrode sheet may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0062] As an example, the positive electrode current collector has two surfaces facing each other in its thickness direction, and the positive electrode active material is disposed on either or both of the two facing surfaces of the positive electrode current collector.

[0063] As an example, the positive electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel or titanium, etc. may be used. The composite current collector may include a polymer material base and a metal layer. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0064] As an example, the positive electrode active material may include at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides and their respective modified compounds. However, the present application is not limited to these materials, and other traditional materials that can be used as positive electrode active materials for batteries can also be used. These positive electrode active materials can be used alone or in combination of two or more. Among them, examples of lithium-containing phosphates may include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and a composite material of lithium iron manganese phosphate and carbon. Examples of lithium transition metal oxides may include, but are not limited to, lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also referred to as NCM 333 )、LiNi 0.5 Co 0.2 Mn 0.3 O2 (also referred to as NCM 523 )、LiNi 0.5 Co 0.25 Mn 0.25 O2 (also referred to as NCM 211 )、LiNi 0.6 Co 0.2 Mn 0.2 O2 (also referred to as NCM 622 )、LiNi 0.8 Co 0.1 Mn 0.1 O2 (also referred to as NCM 811 ), lithium nickel cobalt aluminum oxide (such as LiNi 0.85 Co 0.15 Al 0.05 O2) and its modified compounds, etc.

[0065] In some embodiments, the positive electrode may be a foamed metal. The foamed metal may be a nickel foam, a copper foam, an aluminum foam, an alloy foam, etc. When the foamed metal is used as the positive electrode, the positive electrode active material may not be provided on the surface of the foamed metal, but of course, the positive electrode active material may also be provided. As an example, a lithium source material, potassium metal or sodium metal may also be filled or / and deposited in the foamed metal, and the lithium source material is lithium metal and / or a lithium-rich material.

[0066] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0067] As an example, the negative electrode current collector may be a metal foil, a foamed metal or a composite current collector. For example, as the metal foil, aluminum or stainless steel treated with silver, stainless steel, copper, aluminum, nickel, carbon electrode, nickel or titanium, etc. may be used. The foamed metal may be a nickel foam, a copper foam, an aluminum foam, an alloy foam, etc. The composite current collector may include a polymer material base and a metal layer. The composite current collector may be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0068] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0069] As an example, the negative electrode current collector has two surfaces facing each other in its thickness direction, and the negative electrode active material is disposed on either or both of the two facing surfaces of the negative electrode current collector.

[0070] As an example, the negative electrode active material may adopt the negative electrode active material for battery cells known in the art. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, lithium titanate, etc. The silicon-based material may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The tin-based material may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, the present application is not limited to these materials, and other traditional materials that can be used as negative electrode active materials for batteries may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0071] In some embodiments, the material of the positive electrode current collector may be aluminum, and the material of the negative electrode current collector may be copper.

[0072] In some embodiments, the electrode assembly further includes a separator disposed between the positive electrode and the negative electrode.

[0073] In some embodiments, the separator is a separator membrane. There may be many types of separator membranes, and any known porous separator membrane with good chemical stability and mechanical stability may be selected.

[0074] As an example, the material of the separator may include at least one of glass fiber, non-woven fabric, polyethylene, polypropylene and polyvinylidene fluoride. The separator may be a single-layer film or a multi-layer composite film. When the separator is a multi-layer composite film, the materials of each layer may be the same or different. The separator may be a separate component located between the positive and negative electrodes, or may be attached to the surface of the positive and negative electrodes.

[0075] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive electrode and the negative electrode and serves to transmit ions and isolate the positive and negative electrodes.

[0076] In some embodiments, the battery cell further includes an electrolyte, which plays a role in conducting ions between the positive and negative electrodes. The electrolyte can be liquid, gel or solid. Among them, the liquid electrolyte includes an electrolyte salt and a solvent.

[0077] In some embodiments, the electrolyte salt may include at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bisfluorosulfonyl imide, lithium bistrifluoromethanesulfonyl imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalatoborate, lithium dioxalatoborate, lithium difluorodioxalatophosphate, and lithium tetrafluorooxalatophosphate.

[0078] In some embodiments, the solvent may include at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, cyclopentane, dimethyl sulfone, methyl ethyl sulfone and diethyl sulfone. The solvent may also be an ether solvent. The ether solvent may include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyltetrahydrofuran, diphenyl ether and crown ether.

[0079] Among them, the gel electrolyte includes a skeleton network with a polymer as the electrolyte, combined with an ionic liquid-lithium salt.

[0080] Among them, solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0081] As an example, the polymer solid electrolyte may be polyether (polyethylene oxide), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, a single ion polymer, polyionic liquid-lithium salt, cellulose, and the like.

[0082] As an example, the inorganic solid electrolyte may include an oxide solid electrolyte (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON film), a sulfide solid electrolyte (crystalline lithium superion conductor (lithium germanium phosphosulfide, silver germanium sulfide), amorphous sulfide) and one or more of a halide solid electrolyte, a nitride solid electrolyte and a hydride solid electrolyte.

[0083] As an example, the composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to a polymer solid electrolyte.

[0084] In some embodiments, the electrode assembly is a wound structure, wherein the positive electrode sheet and the negative electrode sheet are wound into the wound structure.

[0085] In some embodiments, the electrode assembly is a laminate structure.

[0086] As an example, a plurality of positive electrode sheets and a plurality of negative electrode sheets may be provided respectively, and the plurality of positive electrode sheets and the plurality of negative electrode sheets may be alternately stacked.

[0087] As an example, a plurality of positive electrode sheets may be provided, and the negative electrode sheet may be folded to form a plurality of stacked folded segments, with a positive electrode sheet being sandwiched between adjacent folded segments.

[0088] As an example, both the positive electrode sheet and the negative electrode sheet are folded to form a plurality of folded sections that are stacked.

[0089] As an example, a plurality of separators may be provided, each of which is provided between any adjacent positive electrode sheets or negative electrode sheets.

[0090] As an example, the separator may be disposed continuously, and may be disposed between any adjacent positive electrode sheets or negative electrode sheets by folding or winding.

[0091] In some embodiments, the shape of the electrode assembly can be cylindrical, flat, or polygonal.

[0092] In some embodiments, the electrode assembly is provided with tabs, which can lead current out of the electrode assembly. The tabs include a positive tab and a negative tab.

[0093] In some embodiments, the battery cell may include a housing. The housing is used to encapsulate components such as the electrode assembly and the electrolyte. The housing may be a steel housing, an aluminum housing, a plastic housing (such as polypropylene), a composite metal housing (such as a copper-aluminum composite housing), or the like.

[0094] As an example, the battery cell may be a cylindrical battery cell, a prismatic battery cell, a soft-pack battery cell or a battery cell of other shapes. The prismatic battery cell includes but is not limited to a square-shell battery cell, a blade-shaped battery cell, a polygonal battery, such as a hexagonal battery, etc.

[0095] 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.

[0096] In some embodiments, the battery may be a battery module. When there are multiple battery cells, the multiple battery cells are arranged and fixed to form a battery module.

[0097] In some embodiments, the battery may be a battery pack, which includes a case and battery cells, wherein the battery cells or battery modules are accommodated in the case.

[0098] In some embodiments, the box body can be used as a part of the chassis structure of the vehicle. For example, part of the box body can become at least a part of the floor of the vehicle, or part of the box body can become at least a part of the cross beam and longitudinal beam of the vehicle.

[0099] In some embodiments, the battery may be an energy storage device, which includes an energy storage container, an energy storage cabinet, and the like.

[0100] Batteries have outstanding advantages such as high energy density, low environmental pollution, high power density, long service life, wide adaptability, and low self-discharge coefficient. They are an important part of the development of new energy today. The development of battery technology must consider many design factors at the same time, such as energy density, cycle life, discharge capacity, charge and discharge rate and other performance parameters. In addition, the safety of the battery also needs to be considered.

[0101] For a general battery cell, the battery cell usually includes an outer shell and an electrode assembly, the electrode assembly is accommodated in the outer shell, the outer shell includes a shell and an end cover, and the end cover covers the opening of the shell. In order to improve the safety of the battery cell, in the related technology, the end cover is usually welded to the opening of the shell or the connection between the end cover and the shell is achieved through a flanging process. However, the assembly process of the battery cell of this structure is relatively complicated, and the assembly of the end cover and the shell is difficult, which is not conducive to improving the production efficiency of the battery cell. In addition, the use environment of the battery cell is relatively complicated, which makes it very easy for the connection between the end cover and the shell to fail during use of the battery cell, resulting in risks such as leakage of the battery cell, which is not conducive to improving the service life and reliability of the battery cell.

[0102] Based on the above considerations, in order to solve the problem that the connection between the end cap and the shell is prone to failure during use of the battery cell, an embodiment of the present application provides a battery cell, which includes a shell and an end cap. A housing cavity is formed inside the shell, and the housing cavity is used to accommodate the electrode assembly. The shell is formed with an opening at one end in the first direction, and the opening is connected to the housing cavity. The end cap covers the opening, and the end cap has a connecting portion inserted into the housing cavity along the first direction. One of the cavity wall surface of the housing cavity and the outer peripheral surface of the connecting portion is provided with a snap-in groove, and the other is convexly provided with a snap-in protrusion, which is snapped into the snap-in groove.

[0103] In a battery cell of this structure, the battery cell is provided with a shell and an end cover, the end cover is covered at the opening of the shell, and the end cover has a connecting portion inserted into the accommodating cavity along a first direction, and a snap groove is provided on one of the cavity wall surface of the accommodating cavity and the outer peripheral surface of the connecting portion, and a snap protrusion is convexly provided on the other, so that the snap protrusion can be snapped into the snap groove after the end cover and the shell are assembled with each other. On the one hand, a battery cell adopting this structure facilitates the assembly between the end cover and the shell, which is conducive to reducing the difficulty of assembly between the end cover and the shell, thereby effectively improving the production efficiency of the battery cell; on the other hand, the snap fit between the snap protrusion and the snap groove can limit the end cover from detaching from the shell along the first direction, thereby improving the connection reliability and structural strength between the end cover and the shell, so as to reduce the phenomenon of failure of the connection between the end cover and the shell during use of the battery cell, thereby effectively reducing the risk of leakage of the battery cell, and helping to improve the reliability and service life of the battery cell.

[0104] The battery cells disclosed in the embodiments of the present application can be used, but not limited to, in electrical devices such as vehicles, ships or aircraft. A power supply system comprising the battery cells and batteries disclosed in the present application can be used to form the electrical device, which is helpful to alleviate the problem of failure of the connection between the end cap and the housing of the battery cell during use, thereby improving the service life and reliability of the battery cell.

[0105] 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.

[0106] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device in an embodiment of the present application.

[0107] Please refer to Figure 1 , Figure 1A 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 inside the vehicle 1000, and the battery 100 may be provided at the bottom of the vehicle 1000, or at the head of the vehicle 1000, or at the 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 or a power source for the vehicle 1000, etc. 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 the starting, navigation and working power requirements of the vehicle 1000 during driving.

[0108] In some embodiments of the present application, the battery 100 can not only serve as an operating power source or a use 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.

[0109] Please refer to Figure 2 and Figure 3 , Figure 2 The structure explosion diagram of the battery 100 provided in some embodiments of the present application is shown in FIG. Figure 3 The schematic diagram of the structure of the battery cell 20 provided in some embodiments of the present application is as follows. The battery 100 comprises a box body 10 and a battery cell 20 , and the battery cell 20 is used to be accommodated in the box body 10 .

[0110] The box body 10 is used to provide an assembly space for the battery cell 20, and the box body 10 can adopt a variety of structures. In some embodiments, the box body 10 may include a first box body 11 and a second box body 12, the first box body 11 and the second box body 12 cover each other, and the first box body 11 and the second box body 12 jointly define an assembly space for accommodating the battery cell 20. The second box body 12 may be a hollow structure with one end open, and the first box body 11 may be a plate-like structure, and the first box body 11 covers the open side of the second box body 12, so that the first box body 11 and the second box body 12 jointly define an assembly space; the first box body 11 and the second box body 12 may also be hollow structures with one side open, and the open side of the first box body 11 covers the open side of the second box body 12.

[0111] Of course, the box body 10 formed by the first box body 11 and the second box body 12 can be in various shapes, such as a cylinder, a cuboid or a cube. Figure 2 In the embodiment, the box body 10 is in the shape of a rectangular parallelepiped.

[0112] In the battery 100, the battery cell 20 disposed in the box 10 may be one or more. When there are more than one battery cell 20 disposed in the box 10, the multiple battery cells 20 may be connected in series, in parallel, or in mixed connection. Mixed connection means that the multiple battery cells 20 are both connected in series and in parallel. The multiple battery cells 20 may be directly connected in series, in parallel, or in mixed connection, and then the whole formed by the multiple battery cells 20 may be accommodated in the box 10; of course, the battery 100 may also be a battery module formed by connecting multiple battery cells 20 in series, in parallel, or in mixed connection, and then the multiple battery modules may be connected in series, in parallel, or in mixed connection to form a whole, and then the whole may be accommodated in the box 10.

[0113] In some embodiments, the battery 100 may further include other structures. For example, the battery 100 may further include a busbar component, which is used to connect the plurality of battery cells 20 to achieve electrical connection between the plurality of battery cells 20 .

[0114] Each battery cell 20 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 20 may be in a rectangular parallelepiped, a cylinder, a prism or other shapes. For example, Figure 2 and Figure 3 In the figure, the battery cell 20 is a cylindrical structure.

[0115] According to some embodiments of the present application, referring to Figure 3 , and please refer to Figure 4 and Figure 5 , Figure 4 A cross-sectional view of a battery cell 20 provided in some embodiments of the present application, Figure 5 for Figure 4 A partial enlarged view of the battery cell 20 at A shown in the figure. The present application provides a battery cell 20, which includes a shell 21 and an end cover 22. A housing chamber 211 is formed inside the shell 21, and the housing chamber 211 is used to accommodate the electrode assembly 23. An opening 212 is formed at one end of the shell 21 in the first direction X, and the opening 212 is connected to the housing chamber 211. The end cover 22 covers the opening 212, and the end cover 22 has a connecting portion 221 inserted into the housing chamber 211 along the first direction X. One of the cavity wall surface of the housing chamber 211 and the outer peripheral surface of the connecting portion 221 is provided with a snap-in groove 2211, and the other is convexly provided with a snap-in protrusion 213, and the snap-in protrusion 213 is snapped in the snap-in groove 2211.

[0116] The shell 21 serves to accommodate the electrode assembly 23 . A receiving cavity 211 is formed inside the shell 21 , and an opening 212 of the shell 21 is connected to the receiving cavity 211 . That is, the shell 21 is a hollow structure with an opening 212 formed at at least one end.

[0117] The accommodating cavity 211 is formed with an opening 212 at at least one end in the first direction X. That is, the housing 21 is a hollow structure with an opening 212 at at least one end in the first direction X. The housing 21 may be formed with an opening 212 at only one end in the first direction X, or may be formed with openings 212 at both ends in the first direction X. For example, Figure 3 and Figure 4 In the figure, the shell 21 has a first end 214 and a second end 215 opposite to each other in the first direction X, the first end 214 of the shell 21 is provided with an opening 212, and the second end 215 of the shell 21 is a bottom wall of the shell 21 and the end cover 22 arranged opposite to each other, that is, only one end of the shell 21 in the first direction X is formed with an opening 212, and the end cover 22 covers the opening 212 of the shell 21 and forms a sealed connection to form a sealed space for accommodating the electrode assembly 23 and the electrolyte.

[0118] The end cap 22 serves to cover the opening 212 of the housing 21 and seal the opening 212 of the housing 21. Figure 4 and Figure 5 In the figure, the end cover 22 includes a cover body 222 and a connecting portion 221. Along the first direction X, the cover body 222 is used to abut against one end of the shell 21 provided with an opening 212 and cover the opening 212, so that the end cover 22 can cover the opening 212 of the shell 21. The connecting portion 221 is protruding from the side of the cover body 222 facing the accommodating cavity 211 of the shell 21.

[0119] For example, in Figure 5 In the embodiment, the cover body 222 extends from the outer circumference of the shell 21 in the radial direction of the battery cell 20, that is, the cover body 222 covers the shell 21 in the first direction X, that is, the projection of the shell 21 in the first direction X is located inside the cover body 222. The radial direction of the battery cell 20 is perpendicular to the first direction X.

[0120] The end cover 22 has a connecting portion 221 inserted into the accommodating cavity 211 along the first direction X, that is, the connecting portion 221 is a portion of the end cover 22 accommodated in the accommodating cavity 211 of the housing 21 .

[0121] One of the cavity wall surface of the accommodating cavity 211 and the outer peripheral surface of the connecting portion 221 is provided with a snap-fitting groove 2211, and the other is provided with a convex snap-fitting protrusion 213, and the convex snap-fitting protrusion 213 is snapped into the snap-fitting groove 2211. In other words, the cavity wall surface of the accommodating cavity 211 may be provided with a snap-fitting groove 2211, and correspondingly, the outer peripheral surface of the connecting portion 221 is provided with a convex snap-fitting protrusion 213, and the convex snap-fitting protrusion 213 is used to be snapped into the snap-fitting groove 2211. Of course, the outer peripheral surface of the connecting portion 221 may also be provided with a snap-fitting groove 2211, and correspondingly, the cavity wall surface of the accommodating cavity 211 is provided with a convex snap-fitting protrusion 213, and the convex snap-fitting protrusion 213 is used to be snapped into the snap-fitting groove 2211.

[0122] In some embodiments, see Figure 4 As shown, the battery cell 20 also includes an electrode assembly 23, which is accommodated in the accommodating cavity 211 of the shell 21. The electrode assembly 23 is a component in the battery cell 20 where electrochemical reactions occur. The structure of the electrode assembly 23 can be various. For example, the electrode assembly 23 can be a wound structure formed by winding a positive electrode sheet, an isolation member, and a negative electrode sheet, or it can be a stacked structure formed by stacking a positive electrode sheet, an isolation member, and a negative electrode sheet.

[0123] For example, in Figure 4 In the embodiment, the electrode assembly 23 is a wound structure formed by winding a positive electrode sheet, a separator and a negative electrode sheet, and the electrode assembly 23 is cylindrical, and the central axis of the electrode assembly 23 extends along the first direction X.

[0124] Exemplarily, the isolation member is an isolation membrane, and a main material of the isolation membrane may be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene and polyvinylidene fluoride.

[0125] Optionally, the electrode assembly 23 accommodated in the accommodation cavity 211 of the housing 21 may be one or more. Figure 4 In the embodiment, an electrode assembly 23 is disposed in the housing 21 of the battery cell 20. Of course, in other embodiments, the number of electrode assemblies 23 contained in the housing cavity 211 of the housing 21 may be two, three, four, five, six, seven or eight.

[0126] Optionally, the shell formed by the shell 21 and the end cap 22 can also be used to contain electrolytes, such as electrolytes, etc. The shell formed by the shell 21 and the end cap 22 can be in various structural forms, such as a cylinder or a cuboid, etc. Similarly, the material of the shell 21 can also be various, such as aluminum or aluminum alloy, etc.

[0127] When assembling the battery cell 20 , the electrode assembly 23 can be placed in the shell 21 first, and the electrolyte can be filled into the shell 21 . Then, the end cover 22 is covered on the opening 212 of the shell 21 , and the protrusion 213 and the snap-fit ​​groove 2211 are snap-fitted to complete the assembly of the battery cell 20 .

[0128] The shell 21 can be in various shapes, such as a cylinder, a cuboid, or a prism structure. The shape of the shell 21 can be determined according to the specific shape of the electrode assembly 23. For example, if the electrode assembly 23 is a cylindrical structure, a shell 21 with a cylindrical structure can be selected; if the electrode assembly 23 is a cuboid structure, a shell 21 with a cuboid structure can be selected. Of course, the structure of the end cap 22 can also be various, such as the end cap 22 being a plate-like structure or a hollow structure with one end open. For example, in Figure 4In the figure, the shell 21 is a cylindrical structure, and correspondingly, the projections of the cover body 222 and the connecting portion 221 of the end cover 22 in the first direction X are both circular, that is, the battery cell 20 is a cylindrical structure, and the central axis of the battery cell 20 extends along the first direction X, that is, the first direction X is the axial direction of the battery cell 20, and the first direction X is also the thickness direction of the end cover 22.

[0129] Of course, it is understandable that the battery cell 20 is not limited to the above structure, and the battery cell 20 may also be other structures. For example, the battery cell 20 may include a shell 21 and two end covers 22. The shell 21 is a hollow structure with openings 212 on both opposite sides in the first direction X. One end cover 22 corresponds to an opening 212 of the shell 21 and forms a sealed connection to form a sealed space for accommodating the electrode assembly 23 and the electrolyte. That is, the shell 21 is formed with openings 212 on both opposite sides, and the two end covers 22 are respectively covered on both sides of the shell 21 to close the corresponding openings 212.

[0130] In some embodiments, see Figure 3 and Figure 4 As shown, the battery cell 20 may further include an electrode terminal 24 , which is insulated and mounted on the housing, and is electrically connected to the electrode assembly 23 to output or input electrical energy of the battery cell 20 .

[0131] Exemplarily, the electrode terminal 24 is insulated and mounted on the bottom wall of the housing 21 that is disposed opposite to the end cap 22 in the first direction X, that is, the electrode terminal 24 is insulated and mounted on the second end 215 of the housing 21, and no electrical connection is formed between the electrode terminal 24 and the housing 21. Of course, in other embodiments, the electrode terminal 24 may also be disposed on the end cap 22.

[0132] Exemplarily, the electrode terminal 24 may be made of various materials, for example, the electrode terminal 24 may be made of copper, iron, aluminum, steel, or aluminum alloy.

[0133] Among them, Figure 4In the embodiment, the electrode assembly 23 has two pole ears 231 with opposite polarities, and the two pole ears 231 are both arranged at one end of the electrode assembly 23 away from the end cover 22 in the first direction X, and the two pole ears 231 are arranged at intervals, one of the two pole ears 231 is electrically connected to the electrode terminal 24, and the other pole ear 231 is electrically connected to the shell 21, so as to realize the input or output of the positive and negative electrodes of the battery cell 20. Of course, in other embodiments, two electrode terminals 24 may be arranged on the shell, and the two pole ears 231 are electrically connected to the two electrode terminals 24 respectively, or the two pole ears 231 may be respectively arranged at the two ends of the electrode assembly 23 in the first direction X, one of the two pole ears 231 is electrically connected to the electrode terminal 24, and the other pole ear 231 is electrically connected to the end cover 22, so as to realize the input or output of the positive and negative electrodes of the battery cell 20.

[0134] It should be noted that the tab 231 of the electrode assembly 23 is a component formed by mutually stacking and connecting the regions on the positive electrode sheet that are not coated with the positive electrode active material layer, or a component formed by mutually stacking and connecting the regions on the negative electrode sheet that are not coated with the negative electrode active material layer. If the tab 231 is used to output the positive electrode of the electrode assembly 23, the tab 231 is a component formed by mutually stacking and connecting the regions on the positive electrode sheet that are not coated with the positive electrode active material layer; if the tab 231 is used to output the negative electrode of the electrode assembly 23, the tab 231 is a component formed by mutually stacking and connecting the regions on the negative electrode sheet that are not coated with the negative electrode active material layer.

[0135] In some embodiments, the battery cell 20 may also include a current collecting component, which is disposed in the accommodating cavity 211 of the shell 21. The current collecting component connects the electrode terminal 24 and the pole ear 231 of the electrode assembly 23 or connects the shell 21 and the pole ear 231 of the electrode assembly 23 to achieve electrical connection between the electrode assembly 23 and the electrode terminal 24 or between the electrode assembly 23 and the shell 21, thereby reducing the difficulty of assembling the battery cell 20.

[0136] Exemplarily, the material of the current collecting component can be various, for example, the material of the current collecting component can be copper, iron, aluminum, steel or aluminum alloy.

[0137] In some embodiments, reference Figure 5 , and please refer to Figure 6 , Figure 6 The axial side view of the battery cell 20 provided in some embodiments of the present application. The battery cell 20 may also include a pressure relief mechanism 25, which is disposed on the end cover 22. The pressure relief mechanism 25 is used to release the pressure inside the battery cell 20 when the internal pressure or temperature of the battery cell 20 reaches a predetermined value. Of course, in other embodiments, the pressure relief mechanism 25 may also be disposed on the housing 21.

[0138] Optionally, the pressure relief mechanism 25 and the end cover 22 may be an integrally formed structure or a separately arranged structure. Figure 6 In the embodiment, the pressure relief mechanism 25 and the end cover 22 are an integrally formed structure, and the pressure relief mechanism 25 is a region where a weak structure is formed on the end cover 22. For example, a notch groove is provided on the end cover 22, and the region where the notch groove is provided on the end cover 22 forms the pressure relief mechanism 25. Of course, in other embodiments, the pressure relief mechanism 25 and the end cover 22 may also be a split structure, and the pressure relief mechanism 25 may be connected to the end cover 22 by welding or the like. Correspondingly, the pressure relief mechanism 25 may be a pressure relief component such as an explosion-proof valve, an explosion-proof disk, an air valve, a pressure relief valve, or a safety valve.

[0139] For example, see Figure 4 , Figure 5 and Figure 6 As shown, along the first direction X, a groove 2221 is further provided on the side of the cover body 222 of the end cover 22 away from the accommodating cavity 211, that is, a groove 2221 is provided on the side of the cover body 222 away from the connecting portion 221, and the pressure relief mechanism 25 is arranged on the bottom surface of the groove 2221, that is, the notched groove is arranged on the bottom surface of the groove 2221, so that the pressure relief mechanism 25 can be protected to a certain extent, so as to reduce the friction or collision between the area of ​​the end cover 22 where the pressure relief mechanism 25 is arranged and the external environment, thereby helping to reduce the risk of wear or damage of the pressure relief mechanism 25, so as to improve the reliability and service life of the battery cell 20.

[0140] In this embodiment, the battery cell 20 is provided with a shell 21 and an end cover 22, the end cover 22 covers the opening 212 of the shell 21, and the end cover 22 has a connecting portion 221 inserted into the accommodating cavity 211 along the first direction X, and a clamping groove 2211 is provided on one of the cavity wall surface of the accommodating cavity 211 and the outer peripheral surface of the connecting portion 221, and a clamping protrusion 213 is convexly provided on the other, so that the clamping protrusion 213 can be clamped in the clamping groove 2211 after the end cover 22 and the shell 21 are assembled with each other. The battery cell 20 with such a structure is convenient for assembling the end cover 22 and the shell 21. , which is conducive to reducing the difficulty of assembling the end cover 22 and the shell 21, thereby effectively improving the production efficiency of the battery cell 20. On the other hand, the snap-fitting of the snap-fitting protrusion 213 and the snap-fitting groove 2211 can limit the end cover 22 from being separated from the shell 21 along the first direction X, thereby improving the connection reliability and structural strength between the end cover 22 and the shell 21, so as to reduce the phenomenon of connection failure between the end cover 22 and the shell 21 during the use of the battery cell 20, thereby effectively reducing the risk of leakage of the battery cell 20, which is conducive to improving the reliability and service life of the battery cell 20.

[0141] In some embodiments, see Figure 4 and Figure 5As shown, a snap-fit ​​groove 2211 is provided on the outer circumference of the connecting portion 221, and a snap-fit ​​protrusion 213 is convexly provided on the cavity wall surface of the accommodating cavity 211. Of course, in other embodiments, the snap-fit ​​protrusion 213 may be convexly provided on the outer circumference of the connecting portion 221, and correspondingly, the snap-fit ​​groove 2211 is provided on the cavity wall surface of the accommodating cavity 211.

[0142] In the present embodiment, the engaging groove 2211 is provided on the outer peripheral surface of the connecting portion 221, and correspondingly, the engaging protrusion 213 is provided on the cavity wall surface of the accommodating cavity 211 of the shell 21, so that when the connecting portion 221 of the end cover 22 is inserted into the accommodating cavity 211 from the opening 212 along the first direction X, the engaging protrusion 213 can be engaged in the engaging groove 2211. The battery cell 20 adopting such a structure can reduce the difficulty of respectively providing the engaging groove 2211 and the engaging protrusion 213 on the end cover 22 and the shell 21, and there is no need to provide the engaging groove 2211 on the shell 21 to increase the wall thickness of the shell 21, thereby facilitating reducing the manufacturing difficulty and manufacturing cost of the battery cell 20.

[0143] According to some embodiments of the present application, see Figure 5 and Figure 6 As shown, a groove 216 is provided on the outer peripheral surface of the housing 21 and at a position corresponding to the protrusion 213 .

[0144] Exemplarily, the groove 216 disposed on the outer circumferential surface of the housing 21 is formed by a rolling process, so as to form the groove 216 on the outer circumferential surface of the housing 21, and form a cam 213 on the cavity wall surface of the accommodating cavity 211 of the housing 21 and at a position corresponding to the groove 216. Of course, the processing method of the cam 213 disposed on the cavity wall surface of the accommodating cavity 211 of the housing 21 is not limited to this. In other embodiments, the cam 213 disposed on the cavity wall surface of the accommodating cavity 211 of the housing 21 can also be formed by a processing process such as casting or welding.

[0145] In this embodiment, a groove 216 is provided on the outer circumferential surface of the shell 21 and at a position corresponding to the protrusion 213, so that a groove 216 is formed on the side of the shell 21 away from the protrusion 213 and in an area corresponding to the protrusion 213, so that the groove 216 can be formed on the outer circumferential surface of the shell 21 by a processing technology such as rolling or stamping, and the protrusion 213 is formed on the cavity wall surface of the accommodating cavity 211 of the shell 21 and at a position corresponding to the groove 216, which helps to reduce the difficulty of setting the protrusion 213 on the shell 21, thereby improving the production efficiency of the battery cell 20.

[0146] According to some embodiments of the present application, see Figure 4 and Figure 5As shown, the clamping groove 2211 is an annular groove extending along the circumference of the connecting portion 221. That is, in the embodiment where the clamping groove 2211 is arranged on the outer circumference of the connecting portion 221, the clamping groove 2211 is an annular groove structure arranged around the connecting portion 221, and the clamping groove 2211 is connected end to end.

[0147] In this embodiment, by setting the snap-fit ​​groove 2211 as an annular groove structure arranged around the circumference of the connecting portion 221, the snap-fit ​​groove 2211 can allow the snap-fitting protrusion 213 at any position to be snapped into when the connecting portion 221 of the end cover 22 is inserted into the accommodating cavity 211, and the snap-fitting of the snap-fitting protrusion 213 and the snap-fitting groove 2211 can be achieved without positioning and matching the snap-fitting protrusion 213 and the snap-fitting groove 2211, so that when the end cover 22 and the shell 21 are assembled with each other, there is no need to rotate the end cover 22 to achieve the assembly between the end cover 22 and the shell 21, which is beneficial to reducing the assembly difficulty between the end cover 22 and the shell 21, and can improve the assembly efficiency between the end cover 22 and the shell 21.

[0148] In some embodiments, see Figure 4 , Figure 5 and Figure 6 As shown, the clamping protrusion 213 is an annular structure extending along the circumference of the connecting portion 221. That is, in the embodiment where the clamping protrusion 213 is arranged on the cavity wall surface of the accommodating cavity 211 of the housing 21, the clamping protrusion 213 is an annular structure arranged around the connecting portion 221, that is, the clamping protrusion 213 extends along the inner circumference of the housing 21 and is connected end to end. Of course, in other embodiments, the clamping protrusion 213 can also be an intermittent structure arranged in sequence along the circumference of the connecting portion 221.

[0149] It should be noted that see Figure 6 As shown, in an embodiment in which a groove 216 is formed on the outer surface of the shell 21 at a position corresponding to the protrusion 213, the protrusion 213 is an annular structure extending along the circumference of the connecting portion 221, and correspondingly, the groove 216 is also an annular groove structure arranged around the circumference of the connecting portion 221.

[0150] In this embodiment, by setting the latching protrusion 213 as an annular structure arranged around the circumference of the connecting portion 221, the latching protrusion 213 can match with the latching groove 2211 of the annular structure. On the one hand, it is convenient for the latching protrusion 213 and the latching groove 2211 to be engaged with each other, which is beneficial to reduce the difficulty of assembling the end cover 22 and the shell 21. On the other hand, it can further improve the connection stability and reliability between the end cover 22 and the shell 21, so as to reduce the phenomenon of connection failure between the end cover 22 and the shell 21 during the use of the battery cell 20, and can improve the balance of mutual force constraints between the end cover 22 and the shell 21.

[0151] According to some embodiments of the present application, see Figure 5As shown, the cross section of the outer surface of the portion of the clamping protrusion 213 clamped in the clamping groove 2211 is arc-shaped, and the cross section is perpendicular to the extension direction of the clamping protrusion 213. In other words, the portion of the clamping protrusion 213 in the cross section perpendicular to the extension direction thereof accommodated in the clamping groove 2211 and facing the groove wall surface of the clamping groove 2211 is an arc-shaped structure.

[0152] Exemplarily, the cross section of the protrusion 213 perpendicular to its extension direction is semicircular.

[0153] It should be noted that the groove wall surface of the clamping groove 2211 is the inner surface of the entire groove of the clamping groove 2211 .

[0154] In the present embodiment, the cross section of the outer surface of the portion of the latching protrusion 213 that is latched in the latching groove 2211 is set to an arc shape perpendicular to the extension direction of the latching protrusion 213, so that the outer surface of the portion of the latching protrusion 213 that is latched in the latching groove 2211 is a smooth arc surface, so that when the connecting portion 221 of the end cover 22 is inserted into the accommodating cavity 211 along the first direction X, the latching protrusion 213 is conveniently latched into the latching groove 2211 under the guidance of its outer surface, which is conducive to improving the smoothness of the latching protrusion 213 being latched in the latching groove 2211, thereby reducing the difficulty of the latching protrusion 213 being latched in the latching groove 2211, and can reduce the phenomenon of mutual locking between the connecting portion 221 of the end cover 22 and the shell 21.

[0155] In some embodiments, see Figure 5 As shown, the groove wall surface of the clamping groove 2211 matches the outer surface of the portion of the clamping protrusion 213 clamped in the clamping groove 2211. That is, the clamping protrusion 213 can fit the groove wall surface of the clamping groove 2211, that is, the shape of the cross section of the groove wall surface of the clamping groove 2211 perpendicular to the extension direction of the clamping groove 2211 is the same as the shape of the cross section of the outer surface of the portion of the clamping protrusion 213 clamped in the clamping groove 2211 perpendicular to the extension direction of the clamping protrusion 213.

[0156] Exemplarily, the cross section of the engaging groove 2211 perpendicular to its extending direction is semicircular.

[0157] In this embodiment, by setting the groove wall surface of the snap-in groove 2211 to a structure that fits with the outer surface of the portion of the snap-in groove 2211 located in the snap-in groove 2211, the shape of the snap-in groove 2211 is made to be the same as the shape of the portion of the snap-in groove 2211 that is snapped into the snap-in groove 2211. On the one hand, the smoothness of the snap-in of the snap-in groove 2211 can be further improved to reduce the difficulty of the snap-in of the snap-in groove 2211. On the other hand, the structural stability of the mutual snap-in of the snap-in groove 2211 with the snap-in groove 2211 can be improved to improve the reliability of the mutual connection between the end cover 22 and the shell 21, thereby further reducing the risk of failure of the connection between the end cover 22 and the shell 21 during use of the battery cell 20.

[0158] According to some embodiments of the present application, see Figure 4 and Figure 5 As shown, there are a plurality of locking protrusions 213 , and the plurality of locking protrusions 213 are arranged at intervals along the first direction X, and the locking grooves 2211 of the locking protrusions 213 are arranged one by one correspondingly.

[0159] The locking protrusions 213 and the locking grooves 2211 are arranged one by one, that is, there are multiple locking grooves 2211, and the multiple locking grooves 2211 are arranged at intervals along the first direction X, and each locking groove 2211 is for a locking protrusion 213 to be locked in.

[0160] For example, in Figure 5 In the embodiment, two locking protrusions 213 arranged at intervals along the first direction X are convexly provided on the wall surface of the accommodating cavity 211, and correspondingly, two clamping grooves 2211 arranged at intervals along the first direction X are provided on the outer peripheral surface of the connecting portion 221, and the two locking protrusions 213 are respectively clamped in the two clamping grooves 2211. Of course, in other embodiments, the number of the locking protrusions 213 and the clamping grooves 2211 can also be three, four, five or six.

[0161] It should be noted that in the embodiment where a groove 216 is provided on the outer circumferential surface of the shell 21 at a position corresponding to the protrusion 213, when there are multiple protrusions 213, there are also multiple grooves 216, and the multiple grooves 216 are arranged at intervals along the first direction X, and each groove 216 is provided corresponding to a protrusion 213.

[0162] For example, in Figure 5 In the embodiment, the dimension of the locking protrusion 213 protruding from the cavity wall of the accommodating cavity 211 is equal to the groove depth of the corresponding locking groove 2211 .

[0163] In the present embodiment, by providing a plurality of latching protrusions 213, the plurality of latching protrusions 213 are arranged at intervals along the first direction X, and the latching grooves 2211 correspond to the latching protrusions 213 one by one, so that there are also a plurality of latching grooves 2211, the plurality of latching grooves 2211 are arranged at intervals along the first direction X, and each latching protrusion 213 is latched in one latching groove 2211, the battery cell 20 adopting such a structure can further improve the ability of the latching protrusion 213 and the latching groove 2211 to cooperate in limiting the end cover 22 from being separated from the shell 21 along the first direction X, thereby further improving the connection reliability and structural strength between the end cover 22 and the shell 21, so as to further reduce the phenomenon of failure of the connection between the end cover 22 and the shell 21 during the use of the battery cell 20, and further reduce the risk of leakage of the battery cell 20, so as to improve the reliability and service life of the battery cell 20.

[0164] According to some embodiments of the present application, see Figure 5As shown, along the first direction X, the shell 21 has a first end 214 and a second end 215 opposite to each other, the opening 212 is arranged at the first end 214, and along the direction from the first end 214 to the second end 215, the radial protrusions 213 of the connecting portion 221 gradually increase in size.

[0165] In the direction from the first end 214 to the second end 215, the protruding dimensions of the plurality of protrusions 213 in the radial direction of the connection portion 221 gradually increase, that is, the protrusion 213 closest to the opening 212 in the first direction X among the plurality of protrusions 213 has the smallest protruding dimension in the radial direction of the connection portion 221, and the protrusion 213 farthest from the opening 212 in the first direction X has the largest protruding dimension in the radial direction of the connection portion 221. The radial direction of the connection portion 221 is perpendicular to the first direction X.

[0166] For example, in Figure 5 In the embodiment, two latching protrusions 213 are protruding from the cavity wall surface of the accommodating cavity 211, and the dimension of the latching protrusion 213 closer to the opening 212 in the first direction X protruding from the cavity wall surface of the accommodating cavity 211 is smaller than the dimension of the latching protrusion 213 farther from the opening 212 in the first direction X protruding from the cavity wall surface of the accommodating cavity 211.

[0167] In this embodiment, among the multiple latching protrusions 213 arranged at intervals along the first direction X, the radial dimensions of the multiple latching protrusions 213 gradually increase in the direction from the first end 214 of the shell 21 to the second end 215 of the shell 21, which is conducive to reducing the difficulty of inserting the end cover 22 from the opening 212 into the accommodating cavity 211 along the first direction X, and can reduce the difficulty of respectively engaging the multiple latching protrusions 213 with the multiple engaging grooves 2211, so as to reduce the difficulty of assembling the end cover 22 and the shell 21.

[0168] According to some embodiments of the present application, see Figure 4 and Figure 5 As shown, along the first direction X, a side of the connection portion 221 facing the accommodating cavity 211 is formed with an avoidance groove 2212. That is, the notch of the avoidance groove 2212 provided on the connection portion 221 is provided facing the electrode assembly 23 in the first direction X, and the avoidance groove 2212 is connected to the accommodating cavity 211, so that the accommodating cavity 211 and components such as the electrode assembly 23 in the accommodating cavity 211 can extend into the avoidance groove 2212.

[0169] In this embodiment, an avoidance groove 2212 is provided on the side of the connecting portion 221 facing the accommodating cavity 211 along the first direction X. On the one hand, the avoidance groove 2212 can avoid other components inside the battery cell 20, which is beneficial to improving the internal space utilization of the battery cell 20, so as to improve the energy density of the battery cell 20. On the other hand, it can effectively improve the ability of the connecting portion 221 to undergo elastic deformation along its radial direction, so that the connecting portion 221 undergoes elastic deformation during the process of being inserted into the accommodating cavity 211, so that the latching protrusion 213 is latched into the latching groove 2211, thereby reducing the difficulty of assembling the end cover 22 and the shell 21.

[0170] In some embodiments, see Figure 4 and Figure 5 As shown, the radial dimension of the avoidance groove 2212 gradually increases from the groove bottom surface of the avoidance groove 2212 to the notch of the avoidance groove 2212. That is to say, the end of the groove side surface of the avoidance groove 2212 close to the notch of the avoidance groove 2212 is closer to the cavity wall surface of the accommodating cavity 211 of the housing 21 in the radial direction of the avoidance groove 2212 than the end of the groove side surface of the avoidance groove 2212 close to the groove bottom surface of the avoidance groove 2212, so that the groove side surface of the avoidance groove 2212 is an arc surface or an inclined surface that gradually tilts outward from one end of the groove bottom surface of the avoidance groove 2212 to one end of the notch of the avoidance groove 2212.

[0171] The radial direction of the avoidance groove 2212 is perpendicular to the first direction X.

[0172] For example, in Figure 5 In the embodiment, the side surface of the avoidance groove 2212 is an arc surface.

[0173] In this embodiment, by setting the avoidance groove 2212 as a structure in which the radial dimension gradually increases from the bottom surface of the avoidance groove 2212 to the notch of the avoidance groove 2212, on the one hand, the collision between the connecting part 221 and other components inside the battery cell 20 can be reduced, and on the other hand, the end of the connecting part 221 close to the notch of the avoidance groove 2212 in the first direction X can be more capable of elastic deformation, so that the connecting part 221 can be further facilitated to elastically deform during the insertion process of the accommodating cavity 211, so that the protrusion 213 is inserted into the snap-in groove 2211, so as to further reduce the difficulty of assembly between the end cover 22 and the shell 21.

[0174] According to some embodiments of the present application, see Figure 5 As shown, the outer peripheral surface of the connecting portion 221 abuts against the cavity wall surface of the accommodating cavity 211. In other words, the outer peripheral surface of the connecting portion 221 and the cavity wall surface of the accommodating cavity 211 fit each other.

[0175] In this embodiment, the outer peripheral surface of the connecting portion 221 of the end cover 22 and the cavity wall surface of the accommodating cavity 211 of the shell 21 are set to a mutually abutting structure to reduce the gap size between the shell 21 and the connecting portion 221, thereby alleviating the phenomenon of accidental separation of the latching protrusion 213 and the latching groove 2211, and further improving the latching effect between the latching protrusion 213 and the latching groove 2211, thereby effectively improving the connection reliability and structural strength between the end cover 22 and the shell 21, which is beneficial to reducing the phenomenon of connection failure between the end cover 22 and the shell 21 during use of the battery cell 20.

[0176] According to some embodiments of this application, please continue to refer to Figure 5 As shown, the battery cell 20 may further include a seal 26 disposed between the locking protrusion 213 and the groove wall of the locking groove 2211 , and the seal 26 is configured to seal the gap between the locking protrusion 213 and the groove wall of the locking groove 2211 .

[0177] Among them, the seal 26 is arranged between the protrusion 213 and the groove wall of the snap-in groove 2211, that is, at least part of the seal 26 is arranged in the snap-in groove 2211, and the seal 26 plays a role in sealing the gap between the protrusion 213 and the groove wall of the snap-in groove 2211.

[0178] Optionally, the structure of the seal 26 can be various. For example, the seal 26 can be a sealant arranged between the protrusion 213 and the groove wall of the snap-in groove 2211, or it can be a sealing ring arranged between the protrusion 213 and the groove wall of the snap-in groove 2211.

[0179] It should be noted that in the embodiment where there are multiple locking protrusions 213 and multiple locking grooves 2211 , there are also multiple sealing members 26 , and a sealing member 26 is disposed between each locking protrusion 213 and the groove wall surface of the locking groove 2211 .

[0180] In this embodiment, a seal 26 is further provided between the latch protrusion 213 and the groove wall of the latch groove 2211. The seal 26 can seal the gap between the latch protrusion 213 and the groove wall of the latch groove 2211, thereby improving the sealing effect between the end cover 22 and the shell 21 to reduce the risk of leakage of the battery cell 20.

[0181] According to some embodiments of this application, see Figure 5 As shown, the sealing member 26 is a sealant disposed between the clamping protrusion 213 and the groove wall surface of the clamping groove 2211. In other words, the sealing member 26 is a sealant filled between the clamping protrusion 213 and the groove wall surface of the clamping groove 2211.

[0182] For example, the sealing member 26 may be polyvinyl chloride sealant or polyurethane sealant.

[0183] In this embodiment, the seal 26 is a sealant arranged between the protrusion 213 and the groove wall of the snap-in groove 2211. The seal 26 with this structure can better fill the gap between the protrusion 213 and the groove wall of the snap-in groove 2211 to improve the sealing effect between the end cover 22 and the shell 21.

[0184] In some embodiments, see Figure 5 As shown, an overflow glue space 27 is formed between the cavity wall surface of the accommodating cavity 211 and the outer peripheral surface of the connecting portion 221. Along the first direction X, the overflow glue space 27 is located on at least one side of the protrusion 213. The overflow glue space 27 is configured to accommodate the sealant overflowed between the protrusion 213 and the groove wall surface of the snap-in groove 2211.

[0185] A glue overflow space 27 is formed between the cavity wall surface of the accommodating cavity 211 and the outer peripheral surface of the connecting portion 221 , that is, the cavity wall surface of the accommodating cavity 211 and the outer peripheral surface of the connecting portion 221 jointly define the glue overflow space 27 .

[0186] The glue overflow space 27 is located at least on one side of the protrusion 213 , that is, the protrusion 213 in the first direction X may be provided with the glue overflow space 27 on only one side, or on both sides.

[0187] For example, in Figure 5 In the embodiment, two locking protrusions 213 arranged at intervals along the first direction X are arranged on the wall surface of the accommodating cavity 211 , and the glue overflow space 27 is located between the two locking protrusions 213 in the first direction X.

[0188] The overflow glue space 27 is configured to accommodate the sealant overflowing between the latch protrusion 213 and the groove wall of the latching groove 2211. That is, the overflow glue space 27 is connected to the gap between the latch protrusion 213 and the groove wall of the latching groove 2211, and the sealant is accommodated in the latching groove 2211, so that when the latch protrusion 213 is latched into the latching groove 2211, the sealant squeezed out of the latching groove 2211 by the latch protrusion 213 can enter the overflow glue space 27.

[0189] In the present embodiment, an overflow glue space 27 is further formed between the cavity wall surface of the accommodating cavity 211 and the outer peripheral surface of the connecting portion 221, and the overflow glue space 27 is arranged on at least one side of the latching protrusion 213 in the first direction X, so that the overflow glue space 27 can accommodate the excess and overflowed sealant between the latching protrusion 213 and the groove wall surface of the latching groove 2211 when the latching protrusion 213 is latched in the latching groove 2211. On the one hand, the battery cell 20 adopting this structure does not need to further process the overflowed sealant, which is beneficial to improving the assembly efficiency of the battery cell 20. On the other hand, surplus sealant can be arranged between the latching protrusion 213 and the groove wall surface of the latching groove 2211 to improve the sealing effect between the latching protrusion 213 and the groove wall surface of the latching groove 2211.

[0190] Of course, the structure of the sealing member 26 is not limited thereto. In some embodiments, the sealing member 26 may also be a sealing ring disposed between the locking protrusion 213 and the groove wall surface of the locking groove 2211 .

[0191] Exemplarily, the material of the sealing member 26 may be rubber, silicone or plastic.

[0192] In this embodiment, the seal 26 is a sealing ring arranged between the latch protrusion 213 and the groove wall of the latch groove 2211. The seal 26 with this structure is convenient for arranging the seal 26 between the latch protrusion 213 and the groove wall of the latch groove 2211, which is beneficial to reduce the difficulty of assembling the seal 26, thereby improving the assembly efficiency of the battery cell 20.

[0193] According to some embodiments of the present application, see Figure 4 and Figure 5 As shown, the end cover 22 may further include a cover body 222 , along the first direction X, the cover body 222 abuts against one end of the shell 21 provided with an opening 212 , and the cover body 222 covers the opening 212 , and the connecting portion 221 is protruded on one side of the cover body 222 facing the accommodating cavity 211 .

[0194] In which, the shell 21 has a first end 214 and a second end 215 relative to each other in the first direction X, the opening 212 is arranged at the first end 214 of the shell 21, and the cover body 222 abuts against the end of the shell 21 where the opening 212 is arranged, that is, the cover body 222 of the end cover 22 abuts against the first end 214 of the shell 21 along the first direction X.

[0195] The cover body 222 covers the opening 212 , that is, the cover body 222 covers the opening 212 in the first direction X, that is, the projection of the opening 212 in the first direction X is located inside the cover body 222 .

[0196] Exemplarily, the cover body 222 and the connecting portion 221 of the end cover 22 are integrally formed structures, which can be formed by casting, stamping or milling. Of course, in other embodiments, the cover body 222 and the connecting portion 221 of the end cover 22 can also be separately arranged structures, and the connecting portion 221 can be connected to the side of the cover body 222 facing the accommodating cavity 211 by welding, bonding or clamping.

[0197] In this embodiment, the end cover 22 also includes a cover body 222, a connecting portion 221 protrudes from a side of the cover body 222 facing the accommodating cavity 211, and the cover body 222 abuts against one end of the shell 21 provided with an opening 212 along the first direction X and covers the opening 212. The end cover 22 with such a structure can, on the one hand, play a certain limiting and positioning role on the end cover 22 through the structure in which the cover body 222 and the shell 21 abut against each other, so as to reduce the phenomenon that the connecting portion 221 of the end cover 22 is over-inserted into the accommodating cavity 211, and on the other hand, can further enhance the effect of the end cover 22 covering the opening 212 of the shell 21, so as to enhance the connection reliability and stability between the end cover 22 and the shell 21.

[0198] According to some embodiments of the present application, see Figure 3 and Figure 4 As shown, the battery cell 20 is cylindrical, and the central axis of the battery cell 20 extends along the first direction X. In other words, the axial direction of the battery cell 20 is the first direction X.

[0199] In the present embodiment, the battery cell 20 is set to be cylindrical so as to facilitate processing to form the battery cell 20 with a cylindrical structure. On the one hand, the battery cell 20 has the advantages of high capacity, long cycle life, and a wide range of operating environment temperature. On the other hand, it is convenient for the connection portion 221 of the end cover 22 to be inserted into the accommodating cavity 211 along the first direction X, and can further reduce the assembly difficulty of the mutual engagement between the locking protrusion 213 and the locking groove 2211, which is beneficial to reducing the manufacturing difficulty of the battery cell 20 and improving the production efficiency of the battery cell 20.

[0200] According to some embodiments of the present application, the present application further provides a battery 100, and the battery 100 includes a battery cell 20 of any of the above schemes.

[0201] Among them, see Figure 2 As shown, the battery 100 may further include a housing 10 , in which the battery cells 20 are accommodated.

[0202] In some embodiments, the box body 10 may include a first box body 11 and a second box body 12 . The first box body 11 and the second box body 12 cover each other, and the first box body 11 and the second box body 12 jointly define an assembly space for accommodating the battery cells 20 .

[0203] Optionally, the second box body 12 can be a hollow structure with one end open, and the first box body 11 can be a plate-like structure. The first box body 11 covers the open side of the second box body 12, so that the first box body 11 and the second box body 12 jointly define an assembly space; the first box body 11 and the second box body 12 can also be hollow structures both with one side open, and the open side of the first box body 11 covers the open side of the second box body 12.

[0204] Of course, the box body 10 formed by the first box body 11 and the second box body 12 can be in various shapes, such as a cylinder or a cuboid. Figure 2 In the embodiment, the box body 10 is a rectangular parallelepiped structure.

[0205] Optionally, the number of battery cells 20 disposed in the box body 10 may be one or more. Figure 2 In the embodiment, a plurality of battery cells 20 are arranged in the box 10 of the battery 100, and the plurality of battery cells 20 can be connected in series, in parallel or in a mixed connection. The mixed connection means that the plurality of battery cells 20 are both connected in series and in parallel. The plurality of battery cells 20 can be directly connected in series, in parallel or in a mixed connection, and then the whole formed by the plurality of battery cells 20 is accommodated in the box 10; of course, the battery 100 can also be a battery module formed by first connecting the plurality of battery cells 20 in series, in parallel or in a mixed connection, and then the plurality of battery modules are connected in series, in parallel or in a mixed connection to form a whole, and then accommodated in the box 10.

[0206] The battery 100 may further include other structures. For example, the battery 100 may further include a busbar component, which connects the plurality of battery cells 20 to achieve electrical connection between the plurality of battery cells 20 .

[0207] It should be noted that, in some embodiments, the battery 100 may not be provided with a box 10, and the battery 100 includes a plurality of battery cells 20, and the battery 100 composed of a plurality of battery cells 20 may be directly assembled on an electrical device to provide electrical energy to the electrical device through the plurality of battery cells 20. In other words, the box 10 may be used as a part of the electrical device. Taking the vehicle 1000 as an example of the electrical device, the box 10 may be used as a part of the chassis structure of the vehicle 1000, for example, a part of the box 10 may become at least a part of the floor of the vehicle 1000, or a part of the box 10 may become at least a part of the crossbeam and longitudinal beam of the vehicle 1000.

[0208] According to some embodiments of the present application, the present application further provides an electrical device, which includes a battery cell 20 according to any of the above schemes, and the battery cell 20 is used to provide electrical energy to the electrical device.

[0209] The electrical device may be any of the aforementioned devices or systems using the battery cell 20 .

[0210] According to some embodiments of the present application, see Figures 3 to 6As shown, the present application provides a battery cell 20, which includes a shell 21, an end cover 22, an electrode assembly 23 and a seal 26. The battery cell 20 is cylindrical, and the central axis of the battery cell 20 extends along the first direction X. A housing cavity 211 is formed inside the shell 21, and the housing cavity 211 is used to accommodate the electrode assembly 23. Along the first direction X, the shell 21 has a first end 214 and a second end 215 opposite to each other, and the first end 214 is provided with an opening 212, and the opening 212 is connected to the housing cavity 211. The end cover 22 covers the opening 212, and the end cover 22 includes a cover body 222 and a connecting portion 221. Along the first direction X, the cover body 222 abuts against one end of the shell 21 provided with the opening 212, and the cover body 222 covers the opening 212, and the connecting portion 221 is convexly arranged on the side of the cover body 222 facing the housing cavity 211, and the connecting portion 221 is inserted into the housing cavity 211. A snap-fit ​​groove 2211 is provided on the outer circumferential surface of the connecting portion 221. The plurality of snap-fit ​​grooves 2211 are arranged at intervals along the first direction X, and the snap-fit ​​grooves 2211 are annular grooves extending along the circumferential direction of the connecting portion 221. A plurality of snap-fit ​​protrusions 213 are convexly provided on the cavity wall surface of the accommodating cavity 211. The plurality of snap-fit ​​protrusions 213 are arranged at intervals along the first direction X, and each snap-fit ​​protrusion 213 is clamped in a snap-fit ​​groove 2211, and the snap-fit ​​protrusion 213 is an annular structure extending along the circumferential direction of the connecting portion 221. From the direction from the first end 214 to the second end 215, the protruding size of the plurality of snap-fit ​​protrusions 213 in the radial direction of the connecting portion 221 gradually increases. A groove 216 is provided on the outer circumferential surface of the housing 21 and at the position corresponding to the snap-fit ​​protrusion 213. The cross section of the outer surface of the portion of the clamping protrusion 213 clamped in the clamping groove 2211 is arc-shaped, and the cross section is perpendicular to the extension direction of the clamping protrusion 213. The groove wall surface of the clamping groove 2211 matches the outer surface of the portion of the clamping protrusion 213 clamped in the clamping groove 2211. Along the first direction X, a side of the connecting portion 221 facing the accommodating cavity 211 is formed with an avoidance groove 2212, and the radial dimension of the avoidance groove 2212 gradually increases from the groove bottom surface of the avoidance groove 2212 to the groove opening of the avoidance groove 2212. The sealing member 26 is disposed between the clamping protrusion 213 and the groove wall surface of the clamping groove 2211, and the sealing member 26 is configured to seal the gap between the clamping protrusion 213 and the groove wall surface of the clamping groove 2211. The sealing member 26 is a sealant disposed between the latch protrusion 213 and the groove wall of the latch groove 2211, and an overflow space 27 is formed between the cavity wall of the accommodating cavity 211 and the outer peripheral surface of the connecting portion 221. Along the first direction X, the overflow space 27 is located on at least one side of the latch protrusion 213, and the overflow space 27 is configured to accommodate the sealant overflowing between the latch protrusion 213 and the groove wall of the latch groove 2211.

[0211] 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.

[0212] 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: A shell having a receiving cavity formed therein, the receiving cavity being used to receive the electrode assembly, and an opening being formed at one end of the shell in the first direction, the opening being communicated with the receiving cavity; as well as an end cover, covering the opening, the end cover having a connecting portion inserted into the accommodating cavity along the first direction; Wherein, one of the cavity wall surface of the accommodating cavity and the outer peripheral surface of the connecting portion is provided with a clamping groove, and the other is provided with a clamping protrusion, and the clamping protrusion is clamped in the clamping groove.

2. The battery cell according to claim 1, characterized in that: The clamping groove is arranged on the outer peripheral surface of the connecting portion, and the clamping protrusion is convexly arranged on the cavity wall surface of the accommodating cavity.

3. The battery cell according to claim 2, characterized in that: A groove is arranged on the outer peripheral surface of the shell and corresponds to the position of the locking protrusion.

4. The battery cell according to any one of claims 1 to 3, characterized in that: The clamping groove is an annular groove extending along the circumference of the connecting portion.

5. The battery cell according to claim 4, characterized in that: The clamping protrusion is an annular structure extending along the circumference of the connecting portion.

6. The battery cell according to claim 5, characterized in that: The cross section of the outer surface of the portion of the locking protrusion locked in the locking groove is arc-shaped, and the cross section is perpendicular to the extending direction of the locking protrusion.

7. The battery cell according to claim 6, characterized in that: The groove wall surface of the clamping groove matches with the outer surface of the portion of the clamping protrusion clamped in the clamping groove.

8. The battery cell according to any one of claims 1 to 3, characterized in that: There are a plurality of the clamping protrusions, and the plurality of the clamping protrusions are arranged at intervals along the first direction, and the clamping protrusions and the clamping grooves are arranged in a one-to-one correspondence.

9. The battery cell according to claim 8, characterized in that: Along the first direction, the shell has a first end and a second end opposite to each other, the opening is arranged at the first end, and along the direction from the first end to the second end, the sizes of the plurality of protrusions protruding in the radial direction of the connecting portion gradually increase.

10. The battery cell according to any one of claims 1 to 3, characterized in that: Along the first direction, a avoiding groove is formed on a side of the connecting portion facing the accommodating cavity.

11. The battery cell according to claim 10, characterized in that: The radial dimension of the avoidance groove gradually increases from the groove bottom surface of the avoidance groove to the groove opening of the avoidance groove.

12. The battery cell according to any one of claims 1 to 3, characterized in that: The outer peripheral surface of the connecting portion abuts against the cavity wall surface of the accommodating cavity.

13. The battery cell according to any one of claims 1 to 3, characterized in that: The battery cell further comprises: The sealing member is disposed between the clamping protrusion and the groove wall surface of the clamping groove, and the sealing member is configured to seal the gap between the clamping protrusion and the groove wall surface of the clamping groove.

14. The battery cell according to claim 13, characterized in that: The sealing member is a sealant arranged between the clamping protrusion and the groove wall surface of the clamping groove.

15. The battery cell according to claim 14, characterized in that: An overflow glue space is formed between the cavity wall of the accommodating cavity and the outer peripheral surface of the connecting portion. Along the first direction, the overflow glue space is located on at least one side of the clamping protrusion, and the overflow glue space is configured to accommodate the sealant overflowing between the clamping protrusion and the groove wall of the clamping groove.

16. The battery cell according to claim 13, characterized in that: The sealing member is a sealing ring arranged between the clamping protrusion and the groove wall surface of the clamping groove.

17. The battery cell according to any one of claims 1 to 3, characterized in that: The end cap also includes: The cover body is abutted against one end of the shell body provided with the opening along the first direction, and the cover body covers the opening, and the connecting portion is protruding on a side of the cover body facing the accommodating cavity.

18. The battery cell according to any one of claims 1 to 3, characterized in that: The battery cell is cylindrical, and a central axis of the battery cell extends along the first direction.

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

20. An electrical device, characterized in that: The invention comprises a battery cell according to any one of claims 1 to 18, wherein the battery cell is used to provide electrical energy.

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