Battery monomer, battery and electric device

Abstract

The utility model provides a battery monomer, a battery and a power utilization device, and relates to the technical field of batteries, the battery monomer comprises an electrode assembly and a shell, the electrode assembly is provided with a first tab and a second tab, and the first tab and the second tab are opposite in polarity; the shell is provided with a containing cavity used for containing the electrode assembly and comprises a frame body and a first plate body, openings are formed in the two sides of the frame body in the second direction, the first plate body is arranged at one opening of the frame body, a containing cavity is defined by the first plate body and the frame body, the frame body is electrically connected with the first tab, and the first plate body is electrically connected with the second tab; an insulating part is arranged between the frame body and the first plate body, the insulating part is in sealed connection with the frame body, the first plate body is provided with a vertical edge structure facing the insulating part, the vertical edge structure extends in the second direction, and the insulating part is in sealed connection with the vertical edge structure. After brazing, the vertical edge structure can release welding stress generated due to different thermal expansion coefficients through small deformation, and the stress at the welding position is eliminated. Therefore, the welding quality is improved, and the welding position is not prone to falling off.

Description

Battery cells, batteries and electrical devices Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a battery cell, a battery, and an electrical device. Background Technology

[0002] In related technologies, if the battery cell casing serves as both the positive and negative terminals, the positive and negative terminals of the casing need to be insulated to avoid short circuits. Common insulation connection methods in existing technologies include nano-injection molding sealing, sealing ring sealing, or ceramic brazing sealing. Compared to these three methods, ceramic brazing sealing has a simpler structure and requires less casing wall thickness.

[0003] However, in ceramic brazing, due to the difference in thermal expansion coefficients between the metal casing and the ceramic material, the internal stress of the component cannot be eliminated after welding. Under long-term stress, cracks easily form at the weld interface, making the component prone to detachment. To alleviate the problem of unresolved stress, the weld width needs to be increased to resist the post-weld stress and prevent the component from detaching. However, increasing the weld width increases the thickness and size of the entire casing, which does not meet the requirements of battery miniaturization and weight reduction. Therefore, how to provide a casing structure suitable for carrying both positive and negative charges is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0004] The purpose of this application is to provide a battery cell, a battery, and an electrical device to solve the technical problem in the prior art where the stress at the weld between the battery cell casing and the ceramic cannot be eliminated, leading to easy detachment of the weld.

[0005] To achieve the above objectives, the technical solution adopted in this application is as follows:

[0006] In a first aspect, this application provides a battery cell, comprising: an electrode assembly and a housing, the electrode assembly having a first tab and a second tab, the first tab and the second tab having opposite polarities; the housing having a receiving cavity for accommodating the electrode assembly, the housing comprising a frame and a first plate, the frame having openings on both sides along a second direction, the first plate being disposed at one of the openings of the frame and defining the receiving cavity therewith, the frame being electrically connected to the first tab, the first plate being electrically connected to the second tab, an insulating member being provided between the frame and the first plate, the insulating member being sealed to the frame, the first plate having a vertical edge structure facing the insulating member, the vertical edge structure extending along the second direction, the insulating member being sealed to the vertical edge structure.

[0007] In one or more embodiments of this application, an insulating member covers the end face of the vertical edge structure, and a first solder layer is provided between the insulating member and the vertical edge structure.

[0008] In one or more embodiments of this application, the thickness of the insulating element is greater than the thickness of the vertical edge structure along a direction perpendicular to the second direction.

[0009] In one or more embodiments of this application, the thickness of the standing edge structure is t1, which satisfies 0.1mm≤t1≤1.2mm.

[0010] In one or more embodiments of this application, the height of the vertical side structure along the second direction is H1, which satisfies H1≥1.5mm.

[0011] In one or more embodiments of this application, an insulating member covers the open end face of the frame, and a second solder layer is provided between the insulating member and the frame.

[0012] In one or more embodiments of this application, the thickness of the insulating element is greater than the thickness of the frame in a direction perpendicular to the second direction.

[0013] In one or more embodiments of this application, the thickness of the frame is t2, which satisfies 0.1mm≤t2≤1.2mm.

[0014] In one or more embodiments of this application, the thickness of the insulating member is t3 along the direction perpendicular to the second direction, satisfying 2mm≤t3≤10mm, and / or the height of the insulating member is H2 along the second direction, satisfying 2mm≤H2≤10mm.

[0015] In one or more embodiments of this application, the insulating member has a sloping structure formed on the outer side away from the receiving cavity, and the sloping structure is disposed closer to the vertical edge structure relative to the frame. The sloping structure is inclined from the outer side of the insulating member away from the receiving cavity toward the receiving cavity.

[0016] In one or more embodiments of this application, the housing further includes: a second plate, the second plate being disposed at another opening of the frame away from the first plate, the second plate having a first positioning portion on the outer edge of the side facing the receiving cavity, the first positioning portion being recessed inward from the surface of the second plate, and the opening end of the frame away from the insulating member being limited to the first positioning portion.

[0017] Secondly, this application also provides a battery comprising at least one battery cell as described in any of the first aspects above.

[0018] In one or more embodiments of this application, at least two battery cells are included. A second positioning part is provided on the outer edge of the side of the first plate away from the receiving cavity. The second positioning part is recessed inward from the surface of the first plate. The frame of one of the two adjacent battery cells is located at the second positioning part of the first plate of the other battery cell away from the open end of the insulating member.

[0019] Thirdly, this application also provides an electrical device, including the battery described in the second aspect.

[0020] Based on the above technical solutions, the battery cell, battery, and power device of this application have at least the following beneficial technical effects:

[0021] The battery cell provided in this application has a casing comprising a frame and a first plate. The first plate is located at one of the openings of the frame and defines a cavity for accommodating an electrode assembly. The first tab of the electrode assembly is electrically connected to the frame, and the second tab is electrically connected to the first plate. Since the first and second tabs have opposite polarities, the frame and the first plate can serve as the positive and negative electrodes, respectively. To avoid short circuits, insulation is required between the frame and the first plate. Therefore, an insulating element is provided between the frame and the first plate, and the insulating element is sealed to both the frame and the first plate. This achieves the requirement of the casing simultaneously carrying positive and negative charges, eliminates the structure of the terminals and adapters in the battery cell, simplifies the casing structure, and increases the space utilization of the battery cell. By setting a vertical edge structure facing the insulating element on the first plate, and brazing the vertical edge structure to the surface of the insulating element, compared to large-area contact welding, the welding surface width of the vertical edge structure is smaller. After brazing, the vertical edge structure can release the welding stress caused by the difference in thermal expansion coefficients through small deformation, eliminating the stress at the weld. Simultaneously, the frame and the insulating parts are brazed together. The frame can be regarded as a vertical edge structure. The welding surface of the frame is relatively narrow. After brazing, the frame can release the welding stress caused by the difference in thermal expansion coefficients through small deformation, thereby eliminating the stress at the weld and improving the welding quality, making the weld less likely to fall off. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 is a three-dimensional structural diagram of a battery cell provided in an embodiment of this application.

[0024] Figure 2 is a schematic diagram of the exploded decomposition structure of a battery cell provided in an embodiment of this application.

[0025] Figure 3 is a side view of a battery cell provided in an embodiment of this application.

[0026] Figure 4 is a cross-sectional view of section AA in Figure 3.

[0027] Figure 5 is an enlarged view of point A in Figure 4.

[0028] Figure 6 is an enlarged view of point A in Figure 4.

[0029] Figure 7 is a three-dimensional structural diagram of multiple battery cells provided in an embodiment of this application.

[0030] Figure 8 is a cross-sectional view of multiple battery cells provided in an embodiment of this application.

[0031] In the figure: 1-Battery cell; 10-Electrode assembly; 11-First tab; 12-Second tab; 20-Housing; 21-Frame; 22-Insulating component; 23-First plate; 24-Second plate; 30-Explosion-proof valve; 31-Insulating film; 221-Sloping structure; 231-Vertical edge structure; 232-Second positioning part; 242-First positioning part. Detailed Implementation

[0032] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0033] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0034] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0035] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0036] In related technologies, for battery cells with a terminal block design, the cell casing needs to function as both the positive and negative electrodes for conduction. Therefore, the casing must carry both positive and negative charges simultaneously. To prevent short circuits, the positive and negative electrodes need to be insulated and sealed. Ceramic brazing sealing structures are relatively simple and have lower requirements for casing wall thickness, making it one of the methods considered in battery cell structural design. However, in ceramic brazing, the welding surfaces of two workpieces are usually directly contacted. After brazing, the difference in thermal expansion coefficients between the metal casing and the ceramic material causes welding stress to remain inside the workpiece and cannot be released. Under long-term stress, cracks can easily form at the welding interface, making the component prone to detachment and affecting the welding quality. To improve welding quality, related technologies typically increase the width of the welding surface to prevent workpiece detachment after brazing. The welding width usually needs to be greater than or equal to 2mm. However, increasing the welding width increases the overall thickness and size of the casing, which does not meet the requirements for battery miniaturization and lightweighting.

[0037] Based on the above considerations, in order to solve the technical problem in the prior art where the stress at the weld between the battery cell casing and the ceramic cannot be eliminated, leading to easy detachment of the weld, this application provides a battery cell, including: an electrode assembly and a casing. The electrode assembly has a first tab and a second tab, the first tab and the second tab having opposite polarities; the casing has a receiving cavity for accommodating the electrode assembly, the casing includes a frame and a first plate, the frame has openings on both sides along a second direction, the first plate is disposed at one of the openings of the frame and defines the receiving cavity with the frame, the frame is electrically connected to the first tab, the first plate is electrically connected to the second tab, an insulating member is provided between the frame and the first plate, the insulating member is sealed to the frame, the first plate has a vertical edge structure facing the insulating member, the vertical edge structure extends along the second direction, and the insulating member is sealed to the vertical edge structure.

[0038] In the technical solution of this application embodiment, the housing is configured to include a frame and a first plate, with the first plate located at one of the openings of the frame and defining a cavity for accommodating the electrode assembly. The first tab of the electrode assembly is electrically connected to the frame, and the second tab of the electrode assembly is electrically connected to the first plate. Since the first and second tabs have opposite polarities, the frame and the first plate can serve as the positive and negative electrodes, respectively. To avoid short circuits, insulation is required between the frame and the first plate. Therefore, an insulating member is provided between the frame and the first plate, and the insulating member is sealed to both the frame and the first plate. This achieves the requirement that the housing can simultaneously carry both positive and negative charges, eliminates the terminal post structure in the battery cell, simplifies the housing structure, and increases the space utilization of the battery cell. By setting a vertical edge structure facing the insulating member on the first plate, and brazing the vertical edge structure to the surface of the insulating member, compared to large-area contact welding, the welding surface width of the vertical edge structure is smaller. After brazing, the vertical edge structure can release the welding stress caused by the difference in thermal expansion coefficients through small deformation, eliminating the stress at the weld. Simultaneously, the frame and the insulating parts are brazed together. The frame can be regarded as a vertical edge structure. The welding surface of the frame is relatively narrow. After brazing, the frame can release the welding stress caused by the difference in thermal expansion coefficients through small deformation, thereby eliminating the stress at the weld and improving the welding quality, making the weld less likely to fall off.

[0039] The battery cells described in this application embodiment may include lithium-ion battery cells, lithium-sulfur battery cells, sodium-lithium-ion battery cells, sodium-ion battery cells, or magnesium-ion battery cells, etc. The shape of the battery cell may be cylindrical, flat, cuboid, or other shapes.

[0040] The technical solution of this application will now be described in detail with reference to the accompanying drawings.

[0041] Please refer to Figures 1 and 2. Figure 1 is a three-dimensional structural diagram of a battery cell provided in an embodiment of this application, and Figure 2 is an exploded decomposition structural diagram of a battery cell provided in an embodiment of this application. The battery cell includes an electrode assembly 10 and a housing 20. The electrode assembly 10 has a first tab 11 and a second tab 12, which have opposite polarities. The housing 20 has a receiving cavity for accommodating the electrode assembly 10. The housing 20 includes a frame 21 and a first plate 23. The frame 21 has openings on both sides along the second direction Y. The first plate 23 is located at one of the openings of the frame 21 and defines the receiving cavity with the frame 21. The frame 21 is electrically connected to the first tab 11, and the first plate 23 is electrically connected to the second tab 12. An insulating member 22 is provided between the frame 21 and the first plate 23. The insulating member 22 is sealed to the frame 21. The first plate 23 has a vertical edge structure 231 facing the insulating member 22. The vertical edge structure 231 extends along the second direction Y, and the insulating member 22 is sealed to the vertical edge structure 231.

[0042] The electrode assembly 10 consists of a positive electrode, a negative electrode, and a separator. The battery cell primarily functions by the movement of metal ions between the positive and negative electrodes. The current collector in the positive electrode without a positive active material layer serves as the positive electrode tab, and the current collector in the negative electrode without a negative active material layer serves as the negative electrode tab. It is understood that the first tab 11 of the electrode assembly 10 can be either a positive or negative tab, while the second tab 12 is a tab with the opposite polarity to the first tab 11.

[0043] The housing 20 is a component used to house the electrode assembly 10, thereby isolating the electrode assembly 10 from the outside environment. It is understood that the frame 21 can be a square frame structure with openings on both sides along the second direction Y, and sequentially connected end-to-end along the first direction X and the third direction Z. Here, the first direction X can be the height direction of the battery cell, the second direction Y can be the thickness or width direction of the battery cell, and the third direction Z can be the length direction of the battery cell. The first plate 23 can be a plate-like structure located at one of the openings of the frame 21, defining the receiving cavity together with the frame 21. In this case, the inner surface of the frame 21 facing the receiving cavity and the inner surface of the first plate 23 facing the receiving cavity are both perpendicular. The frame 21 is electrically connected to the first tab 11, and the first plate 23 is electrically connected to the second tab 12; therefore, the electrical connection surface between the first tab 11 and the frame 21 is perpendicular to the electrical connection surface between the second tab 12 and the first plate 23.

[0044] Both the frame 21 and the first plate 23 can be metal. The material of the frame 21 can be the same as the material of the first electrode tab 11. For example, when the first electrode tab 11 is a positive electrode tab, it can be made of aluminum, and the frame 21 can be made of aluminum or an aluminum alloy. Using the same material makes the welding process easier and improves the welding strength when the first electrode tab 11 and the frame 21 are welded together. Of course, in other embodiments, the frame 21 can also be made of steel.

[0045] The material of the first plate 23 can be the same as that of the second tab 12. Using the same material makes the welding process easier and improves the welding strength when the second tab 12 is welded to the first plate 23. In some embodiments, the material of the first plate 23 is the same as that of the frame 21. For example, in a sodium-ion battery cell, both the first tab 11 and the second tab 12 can be made of aluminum. In this case, both the first plate 23 and the frame 21 can be made of aluminum or an aluminum alloy. Since the materials of the first plate 23 and the frame 21 are the same, the brazing temperature between the frame 21 and the insulating component 22 is the same as the brazing temperature between the first plate 23 and the insulating component 22 during assembly, requiring only one brazing process and simplifying the assembly process. Of course, in some embodiments, the first plate 23 can also be made of steel. The material of the first plate 23 can also be different from that of the frame 21.

[0046] The standing edge structure 231 of the first plate 23 can be understood as a structure that is folded over at the outer edge of the first plate 23 toward the insulating member 22. The standing edge structure 231 extends along the second direction Y, that is, the standing edge structure 231 is arranged along the thickness or width direction of the battery cell, so that the standing edge structure 231 can contact the surface of the insulating member 22 for welding.

[0047] The insulating component 22 is a structural component used to insulate the frame 21 and the first plate 23 to prevent short circuits caused by direct electrical connection between the frame 21 and the first plate 23. The insulating component 22 can be a ceramic component. That is, the frame 21 and the first plate 23 can be insulated by a ceramic component. In this embodiment, the insulating component 22 is sealed to the frame 21 and to the first plate 23 through ceramic brazing. This improves the sealing strength between the insulating component 22 and the metal frame 21 and the metal first plate 23, while requiring less thickness for the frame 21, which can increase the space utilization rate inside the battery cell casing.

[0048] Brazing is a welding method that uses a filler metal with a lower melting point than the workpiece as a filler metal. Appropriate heating melts the filler metal, while the workpiece remains unmelted. The filler metal, through wetting and capillary action, fills the weld seam, and the molten filler metal undergoes a good metallurgical bond with the solid base material of the workpiece, forming a joint. Furthermore, brazing involves relatively high welding temperatures, and the sealing performance is less affected by high temperatures, thus improving the sealing effect.

[0049] In this embodiment, the housing 20 is configured to include a frame 21 and a first plate 23, with the first plate 23 located at one opening of the frame 21 and defining a cavity for accommodating the electrode assembly 10. The first tab 11 of the electrode assembly 10 is electrically connected to the frame 21, and the second tab 12 of the electrode assembly 10 is electrically connected to the first plate 23. Since the first tab 11 and the second tab 12 have opposite polarities, the frame 21 and the first plate 23 can serve as the positive and negative electrodes, respectively. To avoid short circuits, insulation is required between the frame 21 and the first plate 23. Therefore, an insulating member 22 is provided between the frame 21 and the first plate 23, and is sealed to both the frame 21 and the first plate 23 through the insulating member 22. This achieves the requirement that the housing 20 can simultaneously carry both positive and negative charges, eliminates the terminal post structure in the battery cell, simplifies the housing structure, and increases the space utilization of the battery cell. By setting a vertical edge structure 231 facing the insulating component 22, the vertical edge structure 231 is brazed to the surface of the insulating component 22. Compared with large-area contact welding, the welding surface width of the vertical edge structure 231 is smaller. After brazing, the vertical edge structure 231 can release the welding stress caused by the difference in thermal expansion coefficients through small deformation, eliminating the stress at the weld and improving the welding quality. At the same time, the frame 21 is brazed to the surface of the insulating component 22. The frame 21 can be regarded as a vertical edge structure. The welding surface width of the frame 21 is smaller. After brazing, the frame 21 can release the welding stress caused by the difference in thermal expansion coefficients through small deformation, eliminating the stress at the weld and thus improving the welding quality, making the weld less likely to fall off.

[0050] Referring to Figure 2, in some embodiments, the insulating member 22 covers the end face of the vertical edge structure 231, and a first solder layer is provided between the insulating member 22 and the vertical edge structure 231.

[0051] The insulating member 22 can be a ring-shaped structure with its end face covering the open end face of the frame 21. At the same time, the insulating member 22 covers the end face of the vertical edge structure 231. The first solder layer is a solder used to seal the gap between the end face of the insulating member 22 and the vertical edge structure 231 and to connect the insulating member 22 and the vertical edge structure 231. The first solder layer is a layered structure that uses a material with a melting point lower than that of the first plate 23 and the insulating member 22 as a filler metal and fills the joint surface of the insulating member 22 and the vertical edge structure 231 of the first plate 23.

[0052] In this embodiment, a first brazing layer is provided between the insulating component 22 and the vertical edge structure 231 so as to achieve a sealed connection between the insulating component 22 and the first plate 23 through brazing process. Compared with other sealing connection processes, the first brazing layer has a smaller requirement for the wall thickness of the shell 20, which can improve the space utilization rate inside the cavity of the shell 20, reduce the weight of the shell, and increase the energy density of the battery cell.

[0053] Referring to Figure 2, in some embodiments, the thickness of the insulating member 22 is greater than the thickness of the standing edge structure 231 along a direction perpendicular to the second direction Y.

[0054] It is understandable that the thickness of the insulating element 22 is greater than the thickness of the vertical side structure 231 along the direction perpendicular to the second direction Y, that is, along the first direction X and along the third direction Z.

[0055] In this embodiment, the thickness of the insulating component 22 is greater than the thickness of the vertical edge structure 231. The vertical edge structure 231 is welded to the surface of the insulating component 22. The welding width of the vertical edge structure 231 is small, allowing for blade welding between the vertical edge structure 231 and the surface of the insulating component 22. This allows for the release of welding stress caused by the difference in thermal expansion coefficients through the small deformation of the vertical edge structure 231. Blade welding is a high-precision welding technique for thin sheets, blades, or delicate metal parts. By controlling the welding heat input and welding area, it achieves a small-area, high-strength, and low-heat-affected zone connection.

[0056] Referring to Figures 3, 4, and 6, in some embodiments, the thickness of the vertical edge structure 231 is t1, satisfying 0.1mm ≤ t1 ≤ 1.2mm. For example, t1 can be 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.1mm, or 1.2mm. In some embodiments, for example when the first plate 23 is made of aluminum alloy, the thickness t1 of the vertical edge structure 231 satisfies: 0.3mm ≤ t1 ≤ 1.2mm. For example, t1 can be 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.1mm, or 1.2mm. In some other embodiments, when the first plate 23 is made of copper, the copper material has greater strength, and the thickness t1 of the vertical edge structure 231 satisfies: 0.1mm≤t1≤0.3mm, for example, t1 can be 0.1mm, 0.2mm or 0.3mm.

[0057] In this embodiment, the above-mentioned arrangement allows the thickness of the vertical edge structure 231 to be smaller and the welding width to be smaller. This allows for blade welding when it comes into contact with the surface of the insulating component 22. As a result, the welding stress caused by the difference in thermal expansion coefficients can be released through the small deformation of the vertical edge structure 231 after welding, thereby improving the welding quality of the weld.

[0058] Referring to Figure 6, in some embodiments, the height of the vertical side structure 231 along the second direction Y is H1, satisfying H1≥1.5mm. For example, H1 can be 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm or 5.5mm.

[0059] It is understandable that the height of the vertical side structure 231 along the second direction Y is also the height of the vertical side structure 231 protruding along the second direction Y.

[0060] In this embodiment, the height H1 of the vertical edge structure 231 is greater than or equal to 1.5mm, so that the height of the vertical edge structure 231 can allow the vertical edge structure 231 to deform and release the stress after brazing. If the height of the vertical edge structure 231 is less than 1.5mm, the height is too small and it is not easy to release the stress after brazing through deformation, which will lead to poor welding quality.

[0061] Referring to Figure 2, in some embodiments, the insulating member 22 covers the open end face of the frame 21, and a second solder layer is provided between the insulating member 22 and the frame 21.

[0062] The second solder layer is a solder used to seal the gap between the end face of the insulator 22 and the open end face of the frame 21, and to connect the insulator 22 and the frame 21. The second solder layer is a layered structure that uses a material with a lower melting point than the frame 21 and the insulator 22 as a filler metal and fills the mating surface of the insulator 22 and the frame 21.

[0063] In this embodiment, a second brazing layer is provided between the insulating component 22 and the frame 21 to achieve a sealed connection between the insulating component 22 and the frame 21 through brazing. Compared with other sealing connection processes, the second brazing layer requires less wall thickness of the housing 20, which can improve the space utilization rate inside the housing 20's cavity, reduce the weight of the housing, and increase the energy density of the battery cell. At the same time, the brazing process has a high welding temperature, and the sealing performance is less affected by high temperature, which can improve the sealing effect.

[0064] In some embodiments, the thickness of the insulating member 22 is greater than the thickness of the frame 21 along a direction perpendicular to the second direction Y.

[0065] It is understandable that the thickness of the insulating element 22 is greater than the thickness of the frame 21 along the direction perpendicular to the second direction Y, that is, along the first direction X and the third direction Z.

[0066] In this embodiment, the thickness of the insulating component 22 is greater than the thickness of the frame 21. The frame 21 and the surface of the insulating component 22 are contact welded. The welding width of the frame 21 is small, which allows the frame 21 and the surface of the insulating component 22 to be contacted for blade welding. In this way, the welding stress caused by the difference in thermal expansion coefficients can be released through the small deformation of the frame 21, thereby improving the welding quality of the weld.

[0067] Referring to Figure 6, in some embodiments, the thickness of the frame 21 is t2, satisfying 0.1mm ≤ t2 ≤ 1.2mm. For example, t2 can be 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.1mm, or 1.2mm. In some embodiments, such as when the frame 21 is made of aluminum alloy, the thickness t2 of the frame 21 satisfies: 0.3mm ≤ t2 ≤ 1.2mm. For example, t2 can be 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.1mm, or 1.2mm. In some other embodiments, when the frame 21 is made of copper, the copper material has greater strength, and the thickness t2 of the frame 21 satisfies: 0.1mm≤t2≤0.3mm, for example, t2 can be 0.1mm, 0.2mm or 0.3mm.

[0068] In this embodiment, by setting the thickness of the frame 21 within the above-mentioned range, the thickness of the frame 21 is smaller and the welding width is smaller. The frame 21 can contact the surface of the insulating component 22 for blade welding, thereby releasing the welding stress caused by the difference in thermal expansion coefficients through the small deformation of the frame 21 after welding, and improving the welding quality of the weld.

[0069] Referring to Figures 3, 4, and 5, in some embodiments, the thickness of the insulating member 22 along the direction perpendicular to the second direction Y is t3, satisfying 2mm ≤ t3 ≤ 10mm. For example, t3 can be 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, or 10mm.

[0070] In some embodiments, the height of the insulating member 22 along the second direction Y is H2, satisfying 2mm≤H2≤10mm. For example, H2 can be 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm or 10mm.

[0071] In this embodiment, the thickness of the insulating component 22 is set within the aforementioned range to ensure its strength during processing while also taking into account the weight of the battery cell. In some embodiments, the insulating component 22 is a ceramic component. Since ceramics are relatively hard and brittle, when it is machined, its thickness can be between 5 and 10 mm to avoid cracking during processing. When it is molded, its thickness can be between 2 and 5 mm, thereby reducing the weight of the battery cell.

[0072] In some embodiments, along a direction perpendicular to the second direction Y and away from the outside of the receiving cavity, the outer side of the insulating member 22 protrudes beyond the outer side of the standing edge structure 231, and the outer side of the insulating member 22 also protrudes beyond the outer side of the frame 21. In other embodiments, along a direction perpendicular to the second direction Y and towards the inside of the receiving cavity, the inner side of the insulating member 22 protrudes beyond the inner side of the standing edge structure 231, and the inner side of the insulating member 22 also protrudes beyond the inner side of the frame 21. In some embodiments, to reduce the space occupied by the insulating member 22 within the receiving cavity and to avoid the insulating member 22 obstructing the expansion of the electrode assembly 10 within the receiving cavity, the inner side of the insulating member 22 may also be flush with the inner sides of the frame 21 and the standing edge structure 231 when facing towards the inside of the receiving cavity; this is not limited here.

[0073] Referring to Figure 5, in some embodiments, the insulating member 22 has a sloping structure 221 formed on the outer side away from the receiving cavity, and the sloping structure 221 is disposed closer to the upright side structure 231 relative to the frame 21. The sloping structure 221 is inclined from the outer side of the insulating member 22 away from the receiving cavity toward the receiving cavity.

[0074] In this embodiment, by forming a sloping structure 221 on the outer side of the insulating member 22 away from the receiving cavity, the welding fixture during laser welding between the first plate 23 and the adjacent battery cell can be avoided, thus reducing the processing difficulty.

[0075] In some other embodiments, when the height H1 of the vertical edge structure 231 is large, for example, when H1 > 4 mm, the insulating member 22 may not have a sloped structure 221. For example, the cross-section of the insulating member 22 may be square, i.e., no slope is provided. Because the height H1 of the vertical edge structure 231 is relatively high, when the first plate 23 is laser welded to the adjacent battery cell using a laser welding fixture, the insulating member 22 will not obstruct the welding fixture.

[0076] Referring to Figures 2 and 5, in some embodiments, the housing 20 further includes a second plate 24, which is located at another opening of the frame 21 away from the first plate 23. The second plate 24 has a first positioning portion 242 on its outer edge facing the receiving cavity. The first positioning portion 242 is recessed inward from the surface of the second plate 24, and the open end of the frame 21 away from the insulating member 22 is limited to the first positioning portion 242.

[0077] The material of the second plate 24 can be the same as that of the frame 21. Using the same material makes the welding process easier and improves the welding strength when the frame 21 and the second plate 24 are welded together.

[0078] In this embodiment, by placing the second plate 24 at another opening of the frame 21 away from the first plate 23, and limiting the opening end of the frame 21 away from the first plate 23 to the first positioning part 242, a sealed connection between the frame 21 and the second plate 24 can be achieved by laser welding, thereby sealing the electrode assembly 10 inside the housing 20.

[0079] In some embodiments, referring to Figure 2, the frame 21 is provided with an explosion-proof valve 30 to promptly discharge thermal runaway gases from inside the battery cells, preventing the battery cells from exploding. In some embodiments, the frame 21 is provided with an injection hole to inject electrolyte into the battery cells. In some embodiments, the electrode assembly 10 is covered with an insulating film 31 to insulate the electrode assembly 10 from the frame 21, the first plate 23, and the second plate 24, preventing short circuits caused by direct contact between the electrode assembly 10 and the housing 20.

[0080] On the other hand, as shown in FIG7, this application also provides a battery, including at least one of the battery cells 1.

[0081] Referring to Figures 7 and 8, in some embodiments, the battery includes at least two battery cells 1. A second positioning portion 232 is provided on the outer edge of the first plate 23 opposite to the receiving cavity. The second positioning portion 232 is recessed inward from the surface of the first plate 23. The open end of the frame 21 of one of the adjacent battery cells, away from the insulating member 22, is confined to the second positioning portion 232 of the first plate 23 of the other battery cell. The open end of the frame 21 away from the insulating member 22 is laser-welded to the first plate 23.

[0082] At this point, the second plate 24 of the battery cell 1 located on the non-side side of the battery can be replaced by the first plate 23 of the previous battery cell, meaning that two adjacent battery cells 1 share a first plate 23. This allows multiple battery cells to be stacked along the thickness direction, and the frame 21 of the subsequent battery cell to be welded to the first plate 23 of the previous battery cell, thus achieving positive and negative electrical connection between adjacent battery cells. This eliminates the need for adapter plates and other adapter components, reduces the internal resistance of the battery, and improves the energy efficiency of battery charging and discharging.

[0083] On the other hand, this application also provides an electrical device, including the aforementioned battery. The electrical device can be a power source for the electrical device or an energy storage unit for the electrical device. The electrical device may include, but is not limited to, mobile devices (e.g., mobile phones, laptops, etc.), electric vehicles (e.g., pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, electric golf carts, electric trucks, etc.), electric trains, ships and satellites, energy storage systems, etc.

[0084] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery cell, characterized in that, include: An electrode assembly (10) has a first tab (11) and a second tab (12) with opposite polarities; a housing (20) has a receiving cavity for accommodating the electrode assembly (10), the housing (20) comprising a frame (21) and a first plate (23), the frame (21) having openings on both sides along a second direction (Y), the first plate (23) being disposed at one of the openings of the frame (21) and defining the receiving cavity with the frame (21). The frame (21) is electrically connected to the first tab (11), the first plate (23) is electrically connected to the second tab (12), an insulating member (22) is provided between the frame (21) and the first plate (23), the insulating member (22) is sealed to the frame (21), the first plate (23) is provided with a standing edge structure (231) facing the insulating member (22), the standing edge structure (231) extends along the second direction (Y), and the insulating member (22) is sealed to the standing edge structure (231).

2. The battery cell according to claim 1, characterized in that, The insulating component (22) covers the end face of the vertical edge structure (231), and a first solder layer is provided between the insulating component (22) and the vertical edge structure (231).

3. The battery cell according to claim 2, characterized in that, Along a direction perpendicular to the second direction (Y), the thickness of the insulating element (22) is greater than the thickness of the standing edge structure (231).

4. The battery cell according to claim 3, characterized in that, The thickness of the standing edge structure (231) is t1, which satisfies 0.1mm≤t1≤1.2mm.

5. The battery cell according to claim 2, characterized in that, Along the second direction (Y), the height of the standing edge structure (231) is H1, which satisfies H1≥1.5mm.

6. The battery cell according to claim 1, characterized in that, The insulating component (22) covers the open end face of the frame (21), and a second solder layer is provided between the insulating component (22) and the frame (21).

7. The battery cell according to claim 6, characterized in that, Along a direction perpendicular to the second direction (Y), the thickness of the insulating element (22) is greater than the thickness of the frame (21).

8. The battery cell according to claim 7, characterized in that, The thickness of the frame (21) is t2, which satisfies 0.1mm≤t2≤1.2mm.

9. The battery cell according to any one of claims 1 to 8, characterized in that, Along the direction perpendicular to the second direction (Y), the thickness of the insulating element (22) is t3, satisfying 2mm≤t3≤10mm, and / or, along the second direction (Y), the height of the insulating element (22) is H2, satisfying 2mm≤H2≤10mm.

10. The battery cell according to claim 1, characterized in that, The insulating member (22) has a sloping structure (221) formed on its outer side away from the receiving cavity, and the sloping structure (221) is set closer to the upright side structure (231) than the frame (21). The sloping structure (221) is inclined from the outer side of the insulating member (22) away from the receiving cavity toward the receiving cavity.

11. The battery cell according to claim 1, characterized in that, The housing (20) further includes a second plate (24), which is located at another opening of the frame (21) away from the first plate (23). The second plate (24) has a first positioning part (242) on its outer edge facing the receiving cavity. The first positioning part (242) is recessed inward from the surface of the second plate (24), and the opening end of the frame (21) away from the insulating member (22) is limited to the first positioning part (242).

12. A battery, characterized in that, It includes at least one battery cell as described in any one of claims 1 to 11.

13. The battery according to claim 12, characterized in that, The battery includes at least two battery cells. The outer edge of the first plate (23) opposite to the receiving cavity is provided with a second positioning part (232). The second positioning part (232) is recessed inward from the surface of the first plate. The frame (21) of one of the two adjacent battery cells is positioned at the second positioning part (232) of the first plate (23) of the other battery cell, away from the open end of the insulating member (22).

14. An electrical appliance, characterized in that, Includes the battery as described in claim 13.

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