Battery monomer, battery and electric device

Abstract

A battery cell (20), a battery (100) and a power utilization device, the battery cell (20) comprising: a housing component (21) comprising a housing body (24), the housing body (24) internally defining a receiving cavity (204), the housing body (24) being provided with an opening (241) and a first housing wall (242) surrounding the circumferential edge of the opening (241), the first housing wall (242) comprising at least two sections, the section close to the opening (241) in the at least two sections being a first section (2421), the section close to the opening (241) being a second section (2421), and the section close to the first section (2421) being a second section (2422); the thickness of the first section (2421) is greater than that of the other sections; the cover plate (22) covers the opening (241) and is connected with the first section (2421); and the battery core component (23) is arranged in the accommodating cavity (204).

Description

Battery cells, batteries and electrical devices Technical Field

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

[0002] In recent years, new energy vehicles have experienced rapid development. In the field of electric vehicles, the power battery, as the power source, plays an irreplaceable and crucial role. A battery consists of a casing and multiple individual battery cells housed within it. As a core component of new energy vehicles, the battery has high requirements in terms of both safety and lifespan. However, some current battery cells have insufficient casing strength, potentially leading to problems such as fatigue cracking.

[0003] Summary of the Invention

[0004] This application provides a battery cell, a battery, and an electrical device. The battery cell's casing and cover are less prone to breathing fatigue cracking, and it has high energy density and good reliability.

[0005] In a first aspect, embodiments of this application provide a battery cell, comprising: a housing component including a housing body, the interior of which defines a receiving cavity, the housing body having an opening and a first housing wall surrounding the circumferential edge of the opening, the first housing wall including at least two sections, of which the section closest to the opening is the first section, the thickness of the first section being greater than the thickness of the other sections; a cover plate covering the opening and connected to the first section; and a cell component disposed within the receiving cavity.

[0006] In the above technical solution, by setting a thicker first section on the first shell wall, and placing the first section close to the opening, when the cover plate is connected to the first shell wall to form the shell, the cover plate is connected to the thickest first section. The thickest first section has higher structural strength and is less prone to deformation under external forces, thus reducing the risk of fatigue cracking due to repeated deformation. Furthermore, because the first section is thicker, the connection area between the cover plate and the shell is also larger. Therefore, the cover plate and the first section are less likely to separate, resulting in better connection stability and better overall fatigue resistance of the shell, reducing the risk of fatigue cracking. Simultaneously, the portion of the first shell wall away from the opening includes the remaining sections, which mainly define the cavity for accommodating the battery cell components. Therefore, the thickness of the remaining sections can be smaller, allowing for a sufficiently large cavity to accommodate larger battery cell components without excessively increasing the mass of the shell components or significantly reducing the battery's energy density. Thus, the battery cell of this application possesses both good structural strength and high fatigue life, offering better safety in use, and also boasts a higher energy density.

[0007] In some embodiments, at least two sections are multiple sections, and the thickness of the multiple sections decreases sequentially in the direction from the opening to the inside of the shell.

[0008] The above-mentioned technical solution can reduce the possibility of shell cracking during molding and stretching, and has strong manufacturability. At the same time, the section farthest from the opening has the thinnest thickness, which is beneficial to increasing the volume of the cavity, reducing the weight of the shell components, and improving the energy density of the battery.

[0009] In some embodiments, the thickness difference between any two adjacent segments is T, where 0 mm < T ≤ 0.2 mm.

[0010] In the above technical solution, the thickness difference between two adjacent sections will not be too large, the thickness will not change abruptly, the connection between two connected sections is not easy to break after being bent, and the structural strength of the shell is good.

[0011] In some embodiments, the second segment is the one furthest from the opening among at least two segments. The second segment has a starting edge close to the first segment, and the first segment has a terminal edge close to the starting edge. The distance between the terminal edge and the starting edge is L, where 6mm ≤ L ≤ 20mm.

[0012] In the above technical solution, the distance between the terminal edge and the starting edge is within this range, which can define a sufficient space for accommodating the base plate and the insulating sheet.

[0013] In some embodiments, 6mm ≤ L ≤ 10mm.

[0014] In the above technical solution, the distance between the terminal edge and the starting edge is within this range, which can define a sufficient space for accommodating the base plate and the insulating sheet.

[0015] In some embodiments, an opening is formed at one end of the shell body at the opposite ends, and a second shell wall is formed at the other end; the second segment is the one furthest from the opening among at least two segments, the thickness of the second segment is less than the thickness of the other segments, and the end of the second segment furthest from the opening extends to the second shell wall.

[0016] In the above technical solution, the first shell wall and the second shell wall have better integrity, are less prone to cracking, and have better sealing performance. There is no need to consider the problem of adapting to the connection process. Therefore, the thickness of the second section can be set to the thinnest, and the weight of the first section can be as light as possible to improve the energy density of the battery.

[0017] In some embodiments, the thickness of the first segment is H1, wherein 0.5 mm < H1 ≤ 0.9 mm.

[0018] In the above technical solution, on the one hand, the connection difficulty between the first section and the cover plate is reduced, which can better meet the connection strength requirements between the first section and the cover plate, and the structure has good strength. The connection area between the first section and the cover plate is larger, the fatigue resistance of the shell is better, and it is not easy to produce openings and cracks. On the other hand, the thickness of the first section will not be too large, and the weight of the shell will not be too heavy, which is conducive to obtaining a higher battery energy density.

[0019] In some embodiments, the second segment is the one furthest from the opening among at least two segments, and the thickness of the second segment is H2, wherein 0.1 mm ≤ H2 < 0.5 mm.

[0020] In the above technical solution, on the one hand, the thickness of the second section is not too small, which can meet the structural strength requirements of the second section, making the second section less prone to deformation and damage, and with good fatigue aging resistance; on the other hand, the thickness of the second section is not too thick, so that the second section is lighter in weight, which is conducive to the battery obtaining a higher energy density.

[0021] In some embodiments, at least two segments are three, and the segment located in the middle position of the three is the third segment, the thickness of the third segment is H3, wherein 0.3mm < H3 ≤ 0.7mm.

[0022] In the above technical solution, the thickness variation between the first and third sections and between the second and third sections will not be too large, the connection between the first and third sections and the connection between the third and second sections are not prone to breakage, and the structural strength of the third section is also high.

[0023] In some embodiments, a first transition chamfer or a first transition fillet is provided between any two adjacent segments.

[0024] In the above technical solution, on the one hand, there is no sudden change in thickness between two adjacent sections, and the connection between two adjacent sections is not prone to breakage; on the other hand, the shell does not have sharp edges, so it is not easy to scratch the insulating sheet in the cavity, the shell is not easy to wear, and the shell is also more manufacturable.

[0025] In some embodiments, a step is formed between any two adjacent segments, the inner wall surface of the first shell wall located inside the receiving cavity is provided with a step, and the outer wall surface of the first shell wall located outside the receiving cavity is a plane.

[0026] In the above technical solution, the risk of the sheet metal being stretched and cracking during the manufacturing of the shell is low, and the yield rate is high; at the same time, the volume of the cavity is large, and there is a large expansion space when the battery cell expands, so the shell is not easily squeezed and deformed.

[0027] In some embodiments, a step is formed between any two adjacent segments, the outer wall of the first shell wall located outside the receiving cavity is provided with a step, and the inner wall of the first shell wall located inside the receiving cavity is a plane.

[0028] In the above technical solutions, the manufacturing process is relatively simple, which can reduce the manufacturing cost.

[0029] In some embodiments, a stepped portion is formed between any two adjacent segments, the outer wall of the first shell wall located outside the receiving cavity is provided with a stepped portion, and the inner wall of the first shell wall located inside the receiving cavity is provided with a stepped portion.

[0030] In the above technical solution, the risk of the sheet metal breaking due to stretching is low when manufacturing the shell of this embodiment, and the yield rate is high; at the same time, the manufacturing process is relatively simple, which can reduce the manufacturing cost.

[0031] In some embodiments, the first section has a groove located inside the receiving cavity, and the cover plate has a protrusion at its side end near the edge of the opening, the protrusion being located inside the groove.

[0032] In the above technical solution, on the one hand, the connection is simple, and the connection method between the cover plate and the first section is more flexible. For example, welding or fastener connection can be used. After using the above connection methods, welding or fastener connection is performed, resulting in higher connection strength and better connection effect. The structure is simple, the connection cost is low, and the sealing performance of the cover plate sealing the opening is also good.

[0033] In some embodiments, a second transition chamfer or a second transition fillet is formed at the end of the opening away from the receiving cavity.

[0034] In the above technical solution, the open edge is less likely to scratch the battery cell component during the process of loading the battery cell component into the receiving cavity.

[0035] In some embodiments, one end of the shell has an opening and the other end has a second shell wall. The battery cell also includes a terminal post component, and the cell component is connected to the terminal post component.

[0036] The second shell wall has mounting holes, and the pole piece is mounted on the second shell wall and covers the mounting holes; or, the cover plate has mounting holes, and the pole piece is mounted on the cover plate and covers the mounting holes.

[0037] In the above technical solution, the terminal component is installed on the second shell wall and covers the mounting hole, which can effectively reduce the probability of cracking at the weld of the shell and cover plate during battery use and improve the reliability of the battery cell; the terminal component is installed on the cover plate and covers the mounting hole, making assembly easier.

[0038] In some embodiments, the electrode component includes an electrode body, the surface of the electrode body facing the cell component is the inner end face of the electrode body, and the cell component is connected to the inner end face of the electrode body through a conductive part.

[0039] The above technical solution can reduce the difficulty of assembling and connecting the conductive part and the electrode body, improve processing efficiency, and help shorten the length of the conductive part, saving materials and costs.

[0040] In some embodiments, the battery cell component includes an active material coating portion housed in a receiving cavity and an electrode portion connected to the active material coating portion. The electrode portion includes a gathering portion formed by stacking and connecting multiple layers of electrode tabs. At least a portion of the gathering portion is laid on the inner end face of the electrode body and connected to the inner end face of the electrode body.

[0041] In the above technical solution, by laying the folding part on the inner end face of the pole body, the folding part is laid flat and flat. At least part of the folding part falls on the inner end face of the pole body, so that the pole ear will not be damaged due to bending of the folding part, thus improving the conductivity. Moreover, it is convenient to weld the clamping nozzle to press the folding part, thereby improving the connection reliability between the folding part and the pole body.

[0042] In some embodiments, the electrode component includes an electrode body, and the battery cell component includes an active material coating portion housed in a receiving cavity, and an electrode tab portion connected to the active material coating portion, the electrode tab portion being connected to the electrode body via a conductive element.

[0043] In the above technical solution, the conductive component can be connected to the inner end face of the electrode body, thereby shortening the length of the conductive component.

[0044] In some embodiments, the conductive element includes a first connecting segment, the first connecting segment includes two clamping portions, and the electrode portion includes an electrode end, which is clamped between the two clamping portions and connected to the clamping portions.

[0045] In the above technical solution, two clamping parts can be used to limit the end of the electrode tab, thereby improving the connection reliability of the multi-layer electrode tabs in the end of the electrode tab.

[0046] In some embodiments, the surface of the electrode body facing the cell component is the inner end face of the electrode body. The conductive element includes a second connecting segment, which is laid on the inner end face of the electrode body and connected to the inner end face of the electrode body. The conductive element is bent at the connection position between the first connecting segment and the second connecting segment so that the first connecting segment is located on the side of the second connecting segment away from the electrode body. One of the clamping portions is supported on the side of the tab end away from the electrode body.

[0047] In the above technical solution, the support of the tabs by the clamping part can improve the redundancy of the tabs and reduce the risk of short circuits caused by the tabs being inserted into the active material coating part. Moreover, the bent conductive parts can act as a buffer support, reducing the risk of the cell components colliding with the casing components and improving the reliability of the battery cells.

[0048] In some embodiments, the tab portion includes a folded portion formed by stacking and connecting multiple tab sheets, and the conductive element includes a first connecting segment, the folded portion being stacked on one side of the first connecting segment in the thickness direction and connected to the first connecting segment.

[0049] In the above technical solution, the first connecting section is in the form of a plate. The thickness direction of the first connecting section is consistent with that of the gathering part. The two are stacked along the thickness direction of the first connecting section, so the way the gathering part and the conductive part are matched is simple, which is conducive to improving production efficiency.

[0050] In some embodiments, the surface of the electrode body facing the cell component is the inner end face of the electrode body, and the first connecting section is supported on the side of the folding portion away from the electrode body, so that the folding portion is sandwiched between the inner end face of the electrode body and the first connecting section.

[0051] In the above technical solution, the support of the gathering part by the first connecting section can improve the redundancy of the electrode tab and reduce the risk of short circuit caused by the electrode tab being inserted into the active material coating part.

[0052] In some embodiments, the electrode component includes an electrode body, a transition structure, and an insulating sealing structure. The transition structure surrounds the electrode body and is connected to a cover plate or housing. The insulating sealing structure is insulating and sealingly fitted between the transition structure and the electrode body.

[0053] In the above technical solution, since the pole component includes not only the pole body but also a transition structure connected to the housing, and an insulating and sealing structure is provided between the transition structure and the pole body to provide insulation and sealing, when installing the pole component to the housing and connecting the transition structure to the housing, there is no need to provide a seal between the transition structure and the housing, and there is no need to apply a large sealing pressure to meet the compression degree of the seal. This can reduce the stress on the second housing wall or cover plate, protect the housing, and thus help reduce the wall thickness of the housing and reduce material costs.

[0054] In some embodiments, the transition structure is formed as an elongated strip extending along the length direction of the first shell wall, and the outline shape of the pole body matches the outline shape of the transition structure; or, the transition structure is formed as an elongated strip extending along the length direction of the first shell wall, and the pole body is located at the length center of the transition structure and is circular.

[0055] In the above technical solution, the connection position between the adapter structure and the pole body is subjected to uniform force, and the compression of the insulation and sealing structure can be easily controlled to improve the reliability of the sealing fit between the two.

[0056] In some embodiments, the battery cell further includes: a terminal post component disposed on the housing component, the terminal post component including a terminal post body, the cell component including an electrode assembly, the tabs of the electrode assembly being connected to form a folded portion, the folded portion being connected to the terminal post body; and a pressure relief device disposed on the housing component and located on the same side or opposite side to the terminal post component.

[0057] In the above technical solution, the pressure relief device and the terminal post are located on the same side. This simplifies the design of the other shell walls besides the second shell wall, and simplifies the structure and processing of the battery cell. Alternatively, if the pressure relief device and the terminal post are located on opposite sides, there is no need to consider reducing the volume of the terminal post by occupying space in the second shell wall, thus allowing for flexible design of the shape and volume of the terminal post as needed.

[0058] Secondly, embodiments of this application also provide a battery, including the aforementioned battery cell.

[0059] In the above technical solution, the probability of cracking between the battery cell cover and the battery body during use is relatively low, which improves the reliability of the battery and helps to improve the performance of the electrical device.

[0060] In some embodiments, the battery includes a housing assembly, multiple battery cells are housed in the housing assembly, the bottom of the housing assembly is a housing bottom plate, the opening of the housing body faces the housing bottom plate, and a cover plate is disposed on the bottom of the housing body; or, the opening of the housing body faces away from the housing bottom plate, and a cover plate is disposed on the top of the housing body.

[0061] In the above technical solution, once a battery cell experiences thermal runaway, the battery cell can be depressurized from the bottom, eliminating the need for a central exhaust channel design and freeing up more space for the battery cell, which is beneficial for improving battery energy density. At the same time, it can quickly achieve directional depressurization, and the ejected material can be discharged rapidly in a specified direction through the optimal channel, making it less likely to spread to surrounding cells.

[0062] Thirdly, embodiments of this application also provide an electrical device, including the battery described above; the battery is used to provide electrical energy.

[0063] In the above technical solution, the probability of cracking between the battery cell cover and the battery body during use is relatively low, which improves the reliability of the battery and helps to improve the performance of the electrical device. Attached Figure Description

[0064] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0065] Figure 1 is a structural schematic diagram of a vehicle provided in some embodiments of this application;

[0066] Figure 2 is an exploded view of the battery structure provided in some embodiments of this application;

[0067] Figure 3 is a first cross-sectional view of the casing component in a battery cell provided in some embodiments of this application;

[0068] Figure 4 is a second cross-sectional view of the casing component in a battery cell provided in some embodiments of this application;

[0069] Figure 5 is a magnified view of part A in Figure 4;

[0070] Figure 6 is a cross-sectional view of the casing component in a battery cell provided in some other embodiments of this application;

[0071] Figure 7 is a magnified view of part B in Figure 6;

[0072] Figure 8 is a cross-sectional view of the housing component in a battery cell provided in some embodiments of this application;

[0073] Figure 9 is a magnified view of part C in Figure 8;

[0074] Figure 10 is a cross-sectional view of the housing component in a battery cell provided in some embodiments of this application;

[0075] Figure 11 is a magnified view of part D in Figure 10;

[0076] Figure 12 is a cross-sectional view of the housing component in a battery cell provided in some further embodiments of this application;

[0077] Figure 13 is a magnified view of part E in Figure 12;

[0078] Figure 14 is a cross-sectional view of the casing component in a battery cell provided in some embodiments of this application;

[0079] Figure 15 is a magnified view of part F in Figure 14;

[0080] Figure 16 is a three-dimensional structural diagram of the casing component in a battery cell provided in some embodiments of this application;

[0081] Figure 17 is a schematic diagram of the shell processing in some embodiments of this application;

[0082] Figure 18 is a structural schematic diagram of the connection process between the cover plate and the first section in some embodiments of this application;

[0083] Figure 19 is a magnified view of part G in Figure 18;

[0084] Figure 20 is a top view of a battery cell provided in some embodiments of this application;

[0085] Figure 21 is a cross-sectional view along line AA in Figure 20;

[0086] Figure 22 is a cross-sectional view of a battery cell provided in some embodiments of this application;

[0087] Figure 23 is a magnified view of a portion of Figure 22;

[0088] Figure 24 is a magnified view of part H in Figure 23;

[0089] Figure 25 is a schematic diagram of the structure of a battery cell provided in some embodiments of this application;

[0090] Figure 26 is a schematic diagram of the structure of the cell component and the terminal component in a battery cell provided in some embodiments of this application.

[0091] Icons: Battery cell 20; Housing 2; Housing component 21; Cover plate 22; Cell component 23; Active material coating 231; Tab portion 232; Tab end 2321; Tab piece 233; Gathering portion 234; Stacked portion 237; Electrode assembly 235; Axial section of cell component 236; Shell body 24; Opening 241; First shell wall 242; First section 2421; Second section 2422; Third section 2423; Second shell wall 243; First transition chamfer 244; Step portion 245; Groove 246; Protrusion 247; Second transition fillet 248; Mounting hole 249; Receiving cavity 204; Terminal component 25; Terminal body 251; Inner end face of terminal body 2511; Adapter structure 252; Insulating sealing structure 253; Conductive part 26; Conductive component 261; First connecting section 2611; Clamping part 2612; Second connecting section 2613; Pressure relief device 27; Rolled aluminum plate 30; Aluminum shell punch 400; Aluminum shell die 500; Pressing ring 600; Battery 100; Box assembly 10; First part 101; Second part 102; Controller 200; Motor 300; Vehicle 1000. Detailed Implementation

[0092] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0093] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0094] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0095] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0096] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0097] In the embodiments of this application, the same reference numerals denote 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 this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0098] In this application, "multiple" means two or more (including two).

[0099] In this application, the battery cell may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries, magnesium-ion batteries, or solid-state batteries, etc., and the embodiments of this application are not limited thereto. The battery cell may be cylindrical, flat, cuboid, or other shapes, etc., and the embodiments of this application are not limited thereto.

[0100] A single battery cell includes a casing, cell components, and electrolyte. The casing houses the cell components and electrolyte (in solid-state batteries, this can be a solid electrolyte layer located between the positive and negative electrodes). The cell components include at least one electrode assembly, which consists of a positive electrode, a negative electrode, and a separator (this structure is omitted in solid-state batteries). The electrode assembly can be a wound structure or a stacked structure, etc. The battery cell primarily functions by the movement of metal ions between the positive and negative electrodes.

[0101] A positive electrode typically includes a positive current collector and a positive active material layer. The positive active material layer is directly or indirectly coated onto the positive current collector. The positive current collector without a positive active material layer protrudes from the one with a positive active material layer, and serves as the positive electrode tab. Taking a lithium-ion battery as an example, the material of the positive current collector can be aluminum, and the material of the positive active material layer can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc.

[0102] A negative electrode generally includes a negative current collector and a negative active material layer. The negative active material layer is directly or indirectly coated on the negative current collector. The negative current collector without a negative active material layer protrudes from the one with a negative active material layer, and the negative current collector without a negative active material layer serves as the negative electrode tab. The material of the negative current collector can be copper, and the material of the negative active material layer can be carbon or silicon, etc. The material of the separator is not limited; for example, it can be polypropylene or polyethylene, etc.

[0103] In recent years, new energy vehicles have experienced rapid development. In the field of electric vehicles, the power battery, as the power source, plays an irreplaceable and crucial role. A battery consists of a casing and multiple individual battery cells housed within it. As a core component of new energy vehicles, the battery faces high requirements in both safety and performance.

[0104] In related technologies, battery cells are manufactured by coating an active material layer onto a current collector and then cutting it to obtain an electrode assembly consisting of a current collector coated with the active material layer (referred to as the active material coated portion) and a current collector without the active material layer (referred to as the tab). The positive and negative electrode assemblies and a separator are then sequentially stacked or wound to obtain an electrode assembly. Multiple tabs are stacked in the electrode assembly to form a tab section. The tab section connects to an adapter plate to form a conductive section, or the tab section itself forms a conductive section; the active material coated portion and the conductive section form the cell component. The battery cell casing has terminals. During manufacturing, the conductive section is typically welded to the terminals to ensure normal charging and discharging operations.

[0105] Currently, battery casings generally adopt a thin-shell structure of 0.3-0.5mm. The thinner casing wall results in lighter weight and smaller footprint, which is beneficial for improving battery energy density. However, this also increases assembly difficulty and reduces fatigue resistance. The joint between the casing and the cover is easily damaged and cracked, creating gaps that can lead to electrolyte leakage, battery failure, and other unexpected situations. For example, the top of the casing may have an opening, with the terminals mounted on the cover. The cover is then welded to the casing, with the weld located at the very top of the battery cell. However, when assembling the battery cells, the bottom of the casing needs to be fixed. The terminals of adjacent battery cells are connected by conductive components (such as busbars). Since the terminals are mounted on the cover, vibration or deformation during battery use can cause the conductive components to pull on the terminals. This pulling force can easily be transmitted to the weld between the cover and the casing, leading to material fatigue and cracking at the weld, thus affecting the reliability of the battery cells.

[0106] In other related technologies, in order to improve the strength of the casing, the wall thickness of the casing is increased to 0.7mm, which greatly reduces the assembly difficulty. The weld between the cover plate and the casing is less prone to material fatigue cracking, thus improving the fatigue resistance of the casing. However, at the same time, the mass and volume of the casing are also greatly increased, which reduces the energy density of the battery and is not conducive to improving the competitiveness of battery products.

[0107] Based on the above considerations, in order to improve the fatigue resistance of the casing without excessively increasing its mass and volume, and without excessively reducing the battery energy density, this application proposes a battery cell. The battery cell includes a casing component, a cover plate, and a cell component. The casing component includes a shell body, the interior of which defines a receiving cavity. The shell body has an opening and a first shell wall surrounding the circumferential edge of the opening. The first shell wall includes at least two sections, of which the section closest to the opening is the first section, and the thickness of the first section is greater than the thickness of the other sections. The cover plate is disposed on the opening and connected to the first section. The cell component is disposed within the receiving cavity.

[0108] In this battery cell structure, a thicker first segment is formed on the first shell wall, located near the opening. When the cover plate is connected to the first shell wall to form the casing, the cover plate is connected to the thickest first segment. This thickest first segment has higher structural strength and is less prone to deformation under external forces, reducing the likelihood of fatigue cracking due to repeated deformation. Furthermore, the greater thickness of the first segment increases the connection area between the cover plate and the casing, resulting in better connection stability and overall better fatigue resistance of the casing, reducing the likelihood of fatigue cracking. Simultaneously, the portion of the first shell wall away from the opening includes the remaining segments, which primarily define the cavity for accommodating the battery cell components. Therefore, the thickness of these remaining segments can be smaller, allowing for a sufficiently large cavity to accommodate larger battery cell components without excessively increasing the weight of the casing components or significantly reducing the battery's energy density. Thus, the battery cell of this application possesses excellent structural strength and high fatigue life, offering better safety in use, while also achieving a higher energy density.

[0109] This application provides an electrical device that uses a battery as a power source. The electrical device can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0110] For ease of explanation, the following embodiments will be described using a vehicle 1000 as an example of an electrical device according to an embodiment of this application.

[0111] Please refer to Figure 1, which is a structural schematic diagram of a vehicle 1000 provided in some embodiments of this application. The vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery 100 is disposed inside the vehicle 1000, and the battery 100 can be located at the bottom, front, or rear of the vehicle 1000. The battery 100 can be used to power the vehicle 1000; for example, the battery 100 can serve as the operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to supply power to the motor 300, for example, to meet the power needs of the vehicle 1000 during startup, navigation, and driving.

[0112] In some embodiments of this application, the battery 100 can not only serve as the operating power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0113] Please refer to Figure 2, which is an exploded view of a battery 100 provided in some embodiments of this application. The battery 100 includes a housing assembly 10 and battery cells 20, with the battery cells 20 housed within the housing assembly 10.

[0114] The housing assembly 10 provides a receiving space for the battery cell 20, and the housing assembly 10 can adopt various structures. In some embodiments, the housing assembly 10 may include a first portion 101 and a second portion 102, which overlap each other, and together define a receiving space for accommodating the battery cell 20. The second portion 102 may be a hollow structure open at one end, and the first portion 101 may be a plate-like structure, with the first portion 101 covering the open side of the second portion 102 so that the first portion 101 and the second portion 102 together define the receiving space; the first portion 101 and the second portion 102 may also be hollow structures both open on one side, with the open side of the first portion 101 covering the open side of the second portion 102. Of course, the housing assembly 10 formed by the first portion 101 and the second portion 102 can be of various shapes, such as a cylinder, a cuboid, etc.

[0115] The housing assembly 10 can prevent liquids or other foreign objects from affecting the charging or discharging of the individual battery cells 20. Of course, some batteries 100 may not include the aforementioned housing assembly 10 and may be directly installed in the battery mounting compartment of the electrical device.

[0116] In battery 100, there can be multiple battery cells 20, which can be connected in series, parallel, or in a mixed manner. A mixed connection means that multiple battery cells 20 are connected in both series and parallel configurations. Multiple battery cells 20 can be directly connected in series, parallel, or in a mixed manner, and then the entire assembly of multiple battery cells 20 is housed within the housing assembly 10. Alternatively, battery 100 can also be composed of multiple battery cells 20 first connected in series, parallel, or in a mixed manner to form a battery module, and then multiple battery modules are connected in series, parallel, or in a mixed manner to form a whole, which is also housed within the housing assembly 10. Battery 100 may also include other structures; for example, it may include a busbar component for electrical connection between multiple battery cells 20.

[0117] Hereinafter, with reference to the accompanying drawings, a battery cell 20 according to an embodiment of the present application will be described.

[0118] Please refer to Figures 3 to 16. Figure 3 is a first cross-sectional view of the casing component 21 in the battery cell 20 provided in some embodiments of this application; Figure 4 is a second cross-sectional view of the casing component 21 in the battery cell 20 provided in some embodiments of this application; Figure 5 is a partially enlarged view of part A in Figure 4; Figure 6 is a cross-sectional view of the casing component 21 in the battery cell 20 provided in other embodiments of this application; Figure 7 is a partially enlarged view of part B in Figure 6; Figure 8 is a cross-sectional view of the casing component 21 in the battery cell 20 provided in yet another embodiment of this application; Figure 9 is a partially enlarged view of part C in Figure 8; Figure 10 is a cross-sectional view of the casing component 21 in the battery cell 20 provided in some embodiments of this application; Figure 11 is a partial enlarged view of part D in Figure 10; Figure 12 is a cross-sectional view of the casing component 21 in the battery cell 20 provided in some embodiments of this application; Figure 13 is a partial enlarged view of part E in Figure 12; Figure 14 is a cross-sectional view of the casing component 21 in the battery cell 20 provided in some embodiments of this application; Figure 15 is a partial enlarged view of part F in Figure 14; Figure 16 is a three-dimensional structural schematic diagram of the casing component 21 in the battery cell 20 provided in some embodiments of this application.

[0119] The battery cell 20 includes a housing component 21, a cover plate 22, and a cell component 23. The housing component 21 includes a shell body 24, the interior of which defines a receiving cavity 204. The shell body 24 has an opening 241 and a first shell wall 242 surrounding the circumferential edge of the opening 241. The first shell wall 242 includes at least two sections, of which the section closest to the opening 241 is the first section 2421. The thickness of the first section 2421 is greater than the thickness of the other sections. The cover plate 22 covers the opening 241 and is connected to the first section 2421. The cell component 23 is disposed within the receiving cavity 204.

[0120] For example, one end of the casing 24 has an opening 241, and a cover plate 22 covers the opening 241, with the casing 24 and the cover plate 22 together forming a receiving cavity 204. Alternatively, for example, the battery cell 20 may include a casing 24 and two cover plates 22, with openings 241 at both ends of the casing 24, each opening 241 covered by a cover plate 22, and the two cover plates 22 together with the casing 24 forming a receiving cavity 204.

[0121] The cover plate 22 and the shell 24 can be made of aluminum alloy, steel, aluminum-plastic film, plastic or other materials resistant to electrolyte corrosion. In practice, the choice can be made according to design requirements.

[0122] For example, the shell wall 24 surrounding the circumferential edge of the opening 241 and on one or both sides of the shell wall 24 in the width direction is formed as a first shell wall 242; or, for example, the shell wall 24 surrounding the circumferential edge of the opening 241 and on one or both sides of the shell wall 24 in the length direction is formed as a first shell wall 242; or, for example, the shell wall 24 surrounding the circumferential edge of the opening 241 and on one or both sides of the shell wall 24 in the width direction and the shell wall 24 surrounding the circumferential edge of the opening 241 and on one or both sides of the shell wall 24 in the length direction are both formed as a first shell wall 242.

[0123] The first shell wall 242 may consist of only two sections, wherein the thickness of the first section 2421 near the opening 241 is greater than the thickness of the other section. Alternatively, the first shell wall 242 may consist of more than two sections, wherein the thickness of the first section 2421 near the opening 241 is greater than the thickness of the remaining sections, and the thickness of the remaining sections may decrease sequentially in the direction from the opening 241 toward the inside of the shell body 24, or the thickness of the remaining sections may decrease first and then increase, or increase first and then decrease, or the thickness of the remaining sections may vary irregularly.

[0124] Cover plate 22 covers the opening 241 and is connected to the first section 2421. That is, cover plate 22 is connected to the thickest section of the shell 24. The first section 2421, being the thickest, has high structural strength and is less prone to deformation under external forces, thus reducing the risk of fatigue cracking due to repeated deformation. Furthermore, the greater thickness of the first section 2421 results in a larger connection area between cover plate 22 and the shell 24. In summary, the connection strength between cover plate 22 and the shell 24 is better, reducing the risk of fatigue cracking, and the shell 24 has higher structural strength. The thickness of the remaining sections is less than that of the first section 2421. This means that by making the portion accommodating the battery cell component 23 thinner, the shell 24 can be made lighter, and the volume of the accommodating cavity 204 can be larger, thus better meeting the requirements for increased energy density and weight reduction. Specifically, the cover plate 22 can be welded to the first section 2421 or connected to the first section 2421 by fasteners. After the shell body 24 and the cover plate 22 are connected, the shell 2 is formed.

[0125] According to the battery cell 20 of this application embodiment, a thicker first section 2421 is provided on the first shell wall 242, and the first section 2421 is close to the opening 241. When the cover plate 22 is connected to the first shell wall 242 to form the shell 2, the cover plate 22 is connected to the thickest first section 2421. The thickest first section 2421 has higher structural strength and is not easily deformed under external force, and is less prone to fatigue cracking due to repeated deformation. At the same time, because the first section 2421 is thicker, the connection between the cover plate 22 and the first section 2421 is stronger. With a larger area, the cover plate 22 is less likely to separate from the shell 24, resulting in better connection stability and improved overall fatigue resistance of the shell 2, making it less prone to fatigue cracking. Simultaneously, the portion of the first shell wall 242 away from the opening 241 includes the remaining sections, which primarily define the receiving cavity 204 for accommodating the battery cell component 23. Therefore, the thickness of these remaining sections can be smaller, allowing the receiving cavity 204 to be large enough to accommodate the larger battery cell component 23, without excessively increasing the mass of the shell component 21 or significantly reducing the energy density of the battery 100. Thus, the battery cell 20 of this application possesses both good structural strength and high fatigue life, resulting in better safety in use, while also achieving a higher energy density for the battery 100.

[0126] In some embodiments, at least two sections are multiple, and the thickness of the multiple sections decreases sequentially in the direction from the opening 241 toward the inside of the shell 24.

[0127] The thickness of the multiple sections decreases sequentially. In other words, in the direction from the opening 241 to the inside of the shell 24, the multiple sections are the first section 2421, the third section, the fourth section, ..., the Nth section, and the second section 2422. The thickness of the third section is less than that of the first section 2421, the thickness of the fourth section is less than that of the third section, and the thickness of the second section 2422 is less than that of the Nth section.

[0128] As shown in Figures 3 to 5, 8 and 9, there are two sections, and the thickness of the two sections decreases sequentially in the direction from the opening 241 to the inside of the shell 24; as shown in Figures 6, 7 and 10 to 15, there are three sections, and the thickness of the three sections decreases sequentially in the direction from the opening 241 to the inside of the shell 24.

[0129] The thickness of multiple segments decreases sequentially. This can include multiple segments exhibiting a continuous linear or continuous nonlinear trend in thickness variation; or multiple segments exhibiting a discontinuous trend in thickness variation; or multiple segments exhibiting a partially continuous trend in thickness variation and a partially discontinuous trend in thickness variation.

[0130] Referring to Figure 17, which is a schematic diagram of the processing of the shell body 24 in some embodiments of this application, when processing the shell body 24, the circumferential edge of the rolled aluminum plate 30 is first clamped between the aluminum shell die 500 and the pressure ring 600, and then the aluminum shell punch 400 presses the middle part of the rolled aluminum plate 30 from one side, thereby forming the shell body 24 including at least two sections.

[0131] In this embodiment, the thickness of multiple sections decreases sequentially in the direction from the opening 241 towards the inside of the shell 24. This reduces the possibility of the shell 2 cracking during molding and stretching, thus improving manufacturability. At the same time, the section farthest from the opening 241 has the thinnest thickness, which helps to increase the volume of the receiving cavity 204, reduce the weight of the shell component 21, and improve the energy density of the battery 100.

[0132] In some embodiments, the thickness difference between any two adjacent segments is T, where 0 mm < T ≤ 0.2 mm.

[0133] For example, the thickness difference between any two adjacent segments can be the same or different. The thickness difference between any two adjacent segments can be 0.2mm, 0.18mm, 0.16mm, 0.14mm, 0.12mm, 0.1mm, 0.08mm, 0.06mm, 0.04mm, 0.02mm, or any value between any two of these values.

[0134] In this way, the thickness difference between two adjacent sections will not be too large, the thickness will not change abruptly, and the connection between two connected sections will not easily break after being bent, resulting in good structural strength of the shell 24.

[0135] In some embodiments, referring to Figures 5, 7, 9, 11, 13, and 15, the segment furthest from the opening 241 among at least two segments is the second segment 2422. The second segment 2422 has a starting edge close to the first segment 2421, and the first segment 2421 has a terminal edge close to the starting edge. The distance between the terminal edge and the starting edge is L, where 6mm ≤ L ≤ 20mm.

[0136] For example, the distance between the terminal edge and the starting edge can be 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 20mm, or any value between any two of these. In practice, the distance between the terminal edge and the starting edge can be adjusted according to requirements.

[0137] It should be noted that the space defined by the first segment 2421 inside the receiving cavity 204 is typically used to accommodate the cover plate 22, and the space defined by the second segment 2422 inside the receiving cavity 204 is typically used to accommodate the electrode assembly 235. The space defined by the segment between the second segment 2422 and the first segment 2421 inside the receiving cavity 204 is used to accommodate the bottom support plate and insulating sheet in the battery cell 20. The bottom support plate is used to resist the compressive force when the battery cell 20 is compressed, thereby reducing the risk of the electrode assembly 235 being compressed. The insulating sheet is used to cover the outside of the electrode assembly 235, thereby insulating the electrode assembly 235 from the housing 24. The distance between the terminal edge and the starting edge is within this range, which defines sufficient space for accommodating the bottom support plate and the insulating sheet. In addition, the distance between the terminal edge and the starting edge is within this range, that is, the minimum distance between the first segment 2421 and the second segment 2422 is within this range. In this way, the thickness change between the first segment 2421 and the second segment 2422 has a large gradual space, is not prone to abrupt changes, and has better structural strength.

[0138] In some embodiments, referring to Figures 5, 7, 9, 11, 13, and 15, the segment furthest from the opening 241 among at least two segments is the second segment 2422. The second segment 2422 has a starting edge close to the first segment 2421, and the first segment 2421 has a terminal edge close to the starting edge. The distance between the terminal edge and the starting edge is L, where 6mm ≤ L ≤ 10mm.

[0139] For example, the distance between the terminal edge and the starting edge can be 6mm, 7mm, 8mm, 9mm, 10mm, or any value between any two of these. In practice, the distance between the terminal edge and the starting edge can be adjusted according to requirements.

[0140] It should be noted that the space defined by the first segment 2421 inside the receiving cavity 204 is typically used to accommodate the cover plate 22, and the space defined by the second segment 2422 inside the receiving cavity 204 is typically used to accommodate the electrode assembly 235. The space defined by the segment between the second segment 2422 and the first segment 2421 inside the receiving cavity 204 can be used to accommodate the bottom support plate and insulating sheet in the battery cell 20. The bottom support plate is used to resist the compressive force when the battery cell 20 is compressed, thereby reducing the risk of the electrode assembly 235 being compressed. The insulating sheet is used to cover the outside of the electrode assembly 235, thereby insulating the electrode assembly 235 from the housing 24. The distance between the terminal edge and the starting edge is within this range, which defines sufficient space for accommodating the bottom support plate and the insulating sheet. In addition, the distance between the terminal edge and the starting edge is within this range, that is, the minimum distance between the first segment 2421 and the second segment 2422 is within this range. In this way, the thickness change between the first segment 2421 and the second segment 2422 has a large gradual space, the thickness does not change abruptly, and the structural strength is better.

[0141] In some embodiments, as shown in Figures 5, 7, 9, 11, 13, and 15, an opening 241 is formed at one end of the opposite ends of the shell body 24, and a second shell wall 243 is formed at the other end; the second segment 2422 is the segment furthest from the opening 241 among at least two segments, and the thickness of the second segment 2422 is less than the thickness of the other segments, with the end of the second segment 2422 furthest from the opening 241 extending to the second shell wall 243.

[0142] Specifically, the space defined by the second shell wall 243 and the second section 2422 is used to accommodate the electrode assembly 235. The second shell wall 243 is integrally formed with the first shell wall 242. In this way, the integrity of the first shell wall 242 and the second shell wall 243 is better, it is not easy to crack, and the sealing performance is better. There is no need to consider the problem of adapting to the connection process. Therefore, the thickness of the second section 2422 can be set to the thinnest, and the weight of the first section 2421 can be as light as possible to improve the energy density of the battery 100.

[0143] In some embodiments, referring to Figures 5, 7, 9, 11, 13, and 15, the thickness of the first segment 2421 is H1, wherein 0.5 mm < H1 ≤ 0.9 mm.

[0144] That is, the thickness of the first segment 2421 is 0.7 ± 0.2 mm, and the thicknesses of the first segment 2421 and the second segment 2422 are not equal. For example, the thickness of the first segment 2421 can be 0.55 mm, 0.6 mm, 0.65 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.85 mm, 0.9 mm, or any value between any two of these values.

[0145] The thickness of the first section 2421 is within this range. On the one hand, the connection difficulty between the first section 2421 and the cover plate 22 is reduced, which can better meet the connection strength requirements between the first section 2421 and the cover plate 22, and the structure has good strength. The connection area between the first section 2421 and the cover plate 22 is larger, and the fatigue resistance of the shell 24 is better, making it less likely to produce openings and cracks. On the other hand, the thickness of the first section 2421 will not be too large, and the weight of the shell 24 will not be too heavy, which is conducive to obtaining a higher energy density of the battery 100.

[0146] In some embodiments, referring to Figures 5, 7, 9, 11, 13, and 15, the section furthest from the opening 241 among at least two sections is the second section 2422, and the thickness of the second section 2422 is H2, wherein 0.1 mm ≤ H2 < 0.5 mm.

[0147] That is, the thickness of the second segment 2422 is 0.3 ± 0.2 mm, and the thicknesses of the first segment 2421 and the second segment 2422 are not equal. For example, the thickness of the second segment 2422 can be 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, or any value between any two of these values.

[0148] The thickness of the second segment 2422 is within this range. On the one hand, the thickness of the second segment 2422 is not too small, which can meet the structural strength requirements of the second segment 2422, making the second segment 2422 less prone to deformation and damage, and with good fatigue aging resistance. On the other hand, the thickness of the second segment 2422 is not too thick, so the second segment 2422 is lighter, which is conducive to the battery 100 obtaining a higher energy density.

[0149] In some embodiments, referring to Figures 7, 11, 13, and 15, at least two segments are represented as three segments, with the segment located in the middle position being the third segment 2423. The thickness of the third segment 2423 is H3, wherein 0.3mm < H3 ≤ 0.7mm.

[0150] For example, the thickness of the third segment 2423 may be located between the first segment 2421 and the second segment 2422, and the thickness of the third segment 2423 may be 0.5 ± 0.2 mm. For example, the thickness of the third segment 2423 may be 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.55 mm, 0.6 mm, 0.65 mm, 0.7 mm, or any value between any two of these values.

[0151] The thickness of the third segment 2423 is within this range, so the thickness variation between the first segment 2421 and the third segment 2423, and between the second segment 2422 and the third segment 2423 will not be too large. The connection between the first segment 2421 and the third segment 2423, and the connection between the third segment 2423 and the second segment 2422 are not prone to breakage. At the same time, the structural strength of the third segment 2423 is also relatively high.

[0152] In some embodiments, referring to Figures 5, 7, 9, 11, 13, and 15, a first transition chamfer 244 or a first transition fillet is provided between any two adjacent segments.

[0153] The two adjacent sections are connected by a first transition chamfer 244 or a first transition fillet. This ensures that there is no sudden change in thickness between the two adjacent sections and that the connection between the two adjacent sections is less likely to break. On the other hand, the shell 24 does not have sharp edges, so it is less likely to scratch the insulating sheet in the receiving cavity 204. The shell is also less prone to wear and tear, and the shell is more manufacturable.

[0154] In some embodiments, as shown in Figures 8 to 11, a step portion 245 is formed between any two adjacent sections, the step portion 245 is provided on the inner wall surface of the first shell wall 242 located inside the receiving cavity 204, and the outer wall surface of the first shell wall 242 located outside the receiving cavity 204 is a plane.

[0155] In other words, the step portion 245 is located on the inner wall surface inside the receiving cavity 204. The step portion 245 can be an inclined plane or an arc-shaped surface connecting two adjacent sections on the inner wall surface inside the receiving cavity 204. In embodiments with two sections, there can be one step portion 245; in embodiments with more than two sections, there can be multiple step portions 245.

[0156] The step portion 245 is located on the inner wall surface of the first shell wall 242, and the outer wall surface of the first shell wall 242 located outside the receiving cavity 204 is flat. In this way, the risk of the sheet metal being stretched and cracking during the manufacturing of the shell body 24 is low, and the yield rate is high. At the same time, the volume of the receiving cavity 204 is large, and there is a large expansion space when the battery cell component 23 expands, and the shell component 21 is not easily squeezed and deformed.

[0157] In some embodiments, as shown in Figures 3 to 7, a step portion 245 is formed between any two adjacent sections, the outer wall surface of the first shell wall 242 located outside the receiving cavity 204 is provided with the step portion 245, and the inner wall surface of the first shell wall 242 located inside the receiving cavity 204 is a plane.

[0158] In other words, the step portion 245 is located on the outer wall surface outside the receiving cavity 204. The step portion 245 can be an inclined plane or an arc-shaped surface connecting two adjacent sections on the outer wall surface outside the receiving cavity 204. In embodiments with two sections, there can be one step portion 245; in embodiments with more than two sections, there can be multiple step portions 245.

[0159] The stepped portion 245 is located on the outer wall surface of the first shell wall 242, and the inner wall surface located inside the receiving cavity 204 is flat. This simplifies the manufacturing process and reduces manufacturing costs. At the same time, when the battery cells 20 are placed side by side, a cavity is formed between adjacent battery cells 20. The cavity can be used to accommodate other components to optimize or increase the performance of the battery 100. Alternatively, it can reduce the stress generated by the compression between the battery cells 20 when the battery cells 20 expand.

[0160] In some embodiments, as shown in Figures 12 to 15, a step portion 245 is formed between any two adjacent sections, and the first shell wall 242 has the step portion 245 on the outer wall surface outside the receiving cavity 204 and the inner wall surface inside the receiving cavity 204.

[0161] In other words, both the outer and inner surfaces of the first shell wall 242 are provided with stepped portions 245. For example, there are three sections: the section closest to the opening 241 is the first section 2421, the section furthest from the opening 241 is the second section 2422, and the section between the first section 2421 and the second section 2422 is the third section 2423. The stepped portion 245 between the first section 2421 and the third section 2423 can be located on the outer surface of the receiving cavity 204, and the stepped portion 245 between the second section 2422 and the third section 2423 can be located on the inner surface of the receiving cavity 204; or, the stepped portion 245 between the first section 2421 and the third section 2423 can be located on the inner surface of the receiving cavity 204, and the stepped portion 245 between the second section 2422 and the third section 2423 can be located on the outer surface of the receiving cavity 204.

[0162] In manufacturing the casing 24 of this embodiment, the risk of the sheet metal breaking due to stretching is low, resulting in a high yield rate. Simultaneously, the manufacturing process is simpler, reducing production costs. Furthermore, the volume of the receiving cavity 204 can be increased, providing expansion space when the cell component 23 expands, making the casing component 21 less prone to deformation under pressure. Moreover, when the battery cells 20 are placed side-by-side, a cavity can be formed between adjacent battery cells 20. This cavity can be used to accommodate other components to optimize or enhance the performance of the battery 100; or, when the battery cells 20 expand, it reduces the possibility of stress generated by mutual compression between the battery cells 20.

[0163] In some embodiments, as shown in FIG19, FIG19 is a partial enlarged view of part G in FIG18. The first section 2421 is provided with a groove 246 located inside the receiving cavity 204, and the cover plate 22 is provided with a protrusion 247 at the side end near the edge of the opening 241, and the protrusion 247 is provided in the groove 246.

[0164] [Correction 04.07.2024 according to Rule 91] Referring to Figure 18, which is a structural schematic diagram of the connection process between the cover plate 22 and the first section 2421 in some embodiments of this application. As shown in Figure 18(a), in the initial state, the end face of the first section 2421 facing away from the second section 2422 is provided with a flange, and the side end of the cover plate 22 is provided with a protrusion 247. During installation, the protrusion 247 of the cover plate 22 is first placed against the end face of the first section 2421 facing away from the second section 2422 (see Figure 18(b)), and then the flange is bent so that the flange and the end face of the first section 2421 facing away from the second section 2422 together define a groove 246, and at the same time, the protrusion 247 of the cover plate 22 is fixed in the groove 246 (see Figure 18(c)).

[0165] The above connection method offers several advantages. Firstly, it simplifies the connection and provides greater flexibility in connecting the cover plate 22 and the first section 2421. For example, welding or fasteners can be used. Using these connection methods followed by welding or fasteners results in higher connection strength and better connection performance. Secondly, the structure is simple, the connection cost is low, and the cover plate 22 provides good sealing of the opening 241.

[0166] In some embodiments, as shown in Figures 5, 7, 9, 11, 13, and 15, a second transition chamfer or a second transition fillet 248 is formed at the end of the opening 241 away from the receiving cavity 204.

[0167] In other words, the end of the opening 241 away from the receiving cavity 204 may have a second transition chamfer; or, the end of the opening 241 away from the receiving cavity 204 may also have a second transition fillet 248. The second transition chamfer or the second transition fillet 248 may or may not mate with the side end of the cover plate 22 near the edge of the opening 241.

[0168] In the embodiment where the second transition chamfer or second transition fillet 248 mates with the side end of the cover plate 22 near the edge of the opening 241, on the one hand, the edge of the opening 241 is less likely to scratch the battery cell component 23 during the process of inserting the battery cell component 23 into the receiving cavity 204; on the other hand, the second transition chamfer or second transition fillet 248 can play a positioning role in the connection position of the cover plate 22, which is beneficial to quickly determine the fixed position of the cover plate 22. At the same time, it can also increase the connection area between the cover plate 22 and the first section 2421.

[0169] In embodiments where the second transition chamfer or second transition fillet 248 does not mate with the cover plate 22, for example, the cover plate 22 can be directly connected to the end face of the first section 2421 facing away from the second section 2422. In this case, the setting of the second transition chamfer or second transition fillet 248 is beneficial to prevent the edge of the opening 241 from scratching the battery cell component 23 during the process of the battery cell component 23 being installed into the receiving cavity 204.

[0170] According to some embodiments of this application, as shown in FIG3, one end of the shell 24 has an opening 241 and the other end has a second shell wall 243. The battery cell 20 also includes a terminal post 25, and the cell component 23 is connected to the terminal post 25. The second shell wall 243 is provided with a mounting hole 249, and the terminal post 25 is installed on the second shell wall 243 and covers the mounting hole 249. Alternatively, the cover plate 22 is provided with a mounting hole 249, and the terminal post 25 is installed on the cover plate 22 and covers the mounting hole 249.

[0171] The structure of the housing component 21 is not limited. For example, when the terminal component 25 is mounted on the cover plate 22, referring to Figures 20 and 21, one end of the housing body 24 has an opening 241, and the cover plate 22 closes onto the opening 241, with the housing body 24 and the cover plate 22 together forming a receiving cavity 204. Alternatively, for example, the battery cell 20 may include a housing body 24 and two cover plates 22, both ends of the housing body 24 having openings 241, each opening 241 covered by a cover plate 22, the two cover plates 22 and the housing body 24 together forming a receiving cavity 204, with the terminal component 25 mounted on one of the cover plates 22.

[0172] For example, when the pole member 25 is installed on the second shell wall 243, referring to Figures 22, 23, and 25, one end of the shell body 24 has an opening 241, and the cover plate 22 covers the opening 241. The shell body 24 and the cover plate 22 together form a receiving cavity 204, and the end of the shell body 24 opposite to the opening 241 is formed as the second shell wall 243.

[0173] The shell 24 is a single piece, that is, the shell 24 is a single molded part, and includes a first shell wall 242 and a second shell wall 243. The first shell wall 242 surrounds the edge of the second shell wall 243 and extends from the edge of the second shell wall 243 toward one side in the thickness direction of the second shell wall 243. The end of the first shell wall 242 away from the second shell wall 243 defines an opening 241. A cavity is defined between the first shell wall 242 and the second shell wall 243. The cavity constitutes at least a part of the receiving cavity 204.

[0174] In the above technical solution, since the cell component 23 housed in the housing component 21 is connected to the terminal component 25 installed on the second housing wall 243, when the battery 100 vibrates or deforms, the terminal components 25 connected by the busbar component will pull on each other. Since the terminal component 25 is set on the end wall opposite to the opening 241 of the housing body 24, the force on the terminal component 25 will be preferentially transmitted to the housing body 24 instead of directly acting on the cover plate 22. This not only extends the distance of force transmission to the weld between the housing body 24 and the cover plate 22, but also causes the housing body 24 to deform preferentially when under force, thereby reducing the force on the weld between the housing body 24 and the cover plate 22. This can effectively reduce the probability of cracking at the weld between the housing body 24 and the cover plate 22 during the use of the battery 100 and improve the reliability of the battery cell 20.

[0175] Specifically, when the terminal component 25 is installed on the second shell wall 243, if the terminal component 25 is first installed in the mounting hole 249 of the second shell wall 243 and then the cell component 23 is installed into the shell body 24, it is difficult to connect the cell component 23 and the terminal component 25. However, in the embodiments of this application, the cell component 23 and the terminal component 25 can be connected first, and then the terminal component 25 can be assembled and connected to the shell component 21. This can satisfy the connection requirements of the cell component 23 and the terminal component 25, as well as the connection requirements of the terminal component 25 and the shell component 21, thereby improving the reliability and processability of the battery cell 20.

[0176] According to some embodiments of this application, referring to Figures 21 and 23, the electrode post component 25 includes an electrode post body 251. The surface of the electrode post body 251 facing one end of the cell component 23 (i.e., the surface facing the active material coating portion 231) is the inner end face 2511 of the electrode post body. The cell component 23 is connected to the inner end face 2511 of the electrode post body through a conductive portion 26 (e.g., a tab portion 232 or a conductive element 261). The cell component 23 includes one or more electrode assemblies 235. The portion of the current collector in the electrode assembly 235 coated with an active material layer constitutes the active material coating portion 231, and the portion not coated with an active material layer constitutes the tab portion 232.

[0177] This reduces the difficulty of assembling and connecting the conductive part 26 and the electrode body 251, improves processing efficiency, and helps to shorten the length of the conductive part 26, saving materials and costs.

[0178] According to some embodiments of this application, please refer again to Figures 21 and 23. At least a portion of the conductive part 26 is laid on the inner end face 2511 of the electrode body. Thus, by laying at least a portion of the conductive part 26 on the inner end face of the electrode body 251, the at least portion of the conductive part 26 is laid flat, and the projection of the at least portion of the conductive part 26 falls on the inner end face of the electrode body 251. This improves the connection reliability between the conductive part 26 and the electrode body 251, increases the connection area between the conductive part 26 and the electrode body 251, and enhances conductivity.

[0179] For example, when the battery cell 202 is in an assembled state (as shown in Figures 21 and 23), the inner end face of the terminal body 251 is parallel to the axial section 236 of the cell component, and the direction of the tab of the cell component 23 is the direction in which the active material coating portion 231 extends out of the tab portion 232, which is perpendicular to the first shell wall 242. This facilitates the processing and design of the terminal body 251.

[0180] According to some embodiments of this application, when the battery cell 202 is in an assembled state (e.g., as shown in FIG. 26), the inner end face 2511 of the electrode post body is inclined relative to the axial section 236 of the cell component, and the axial section 236 of the cell component is perpendicular to the tab direction of the cell component 23. The tab direction of the cell component 23 is the direction in which the active material coating portion 231 extends out of the tab portion 232, and this direction is perpendicular to the first shell wall 242. In this way, before laying at least a portion of the conductive part 26 on the inner end face of the electrode body 251, the electrode component 25 can be adjusted so that the inner end face of the electrode body 251 is parallel to the output tab direction of the cell component 23. This facilitates laying at least a portion of the conductive part 26 on the inner end face of the electrode body 251, providing a larger welding operation space. Moreover, at this time, the line connecting the two ends of the electrode body 251 (i.e., the end closer to the cell component 23 and the end farther from the cell component 23) is inclined to the output tab direction of the cell component 23. Thus, after the conductive part 26 is connected to the electrode body 251, the electrode component 25 can be rotated less than 90°, which satisfies the requirement that the line connecting the two ends of the electrode body 251 is parallel to the second shell wall 243 or the cover plate 22. This allows the inner end face of the electrode body 251 to be parallel to the axial section 236 of the cell component, reducing the rotation angle of the electrode component 25 and shortening the length of the conductive part 26.

[0181] According to some embodiments of this application, the battery cell component 23 includes an active material coating portion 231 housed in a receiving cavity 204, and an electrode portion 232 connected to the active material coating portion 231. The electrode portion 232 includes a gathering portion 234 formed by stacking and connecting multiple layers of electrode sheets 233.

[0182] In this way, the multi-layered tabs 233 are connected to form a converged portion 234, making the multi-layered tabs 233 in the converged portion 234 electrically conductive. That is, the multi-layered tabs 233 in the converged portion 234 not only have a stacked arrangement, but also have a connected and conductive relationship. The connection method of the multi-layered tabs 233 in the converged portion 234 is not limited, and can be welding (such as ultrasonic welding, ultrasonic pre-welding and laser welding, resistance welding, pressure welding, or brazing, etc.), through-hole connection, or bonding with conductive adhesive, etc. For example, multi-layered tabs 233 of the same polarity can be ultrasonically welded, and the resulting ultrasonic weld mark is the converged portion 234.

[0183] For example, the multiple layers of tabs 233 in the gathering portion 234 can belong to the same electrode assembly 235 or belong to different electrode assemblies 235. That is, several layers of tabs 233 of the same polarity in the same electrode assembly 235 can be connected to form the gathering portion 234, or several layers of tabs 233 of the same polarity in different electrode assemblies 235 can be connected to form the gathering portion 234. For example, all the tabs 233 of the same polarity in the cell component 23 can be connected to form the gathering portion 234, which can reduce the number of gathering portions 234.

[0184] In the above technical solution, by pre-connecting multiple layers of tabs 233 in the tab portion 232 to form a gathering portion 234, the gathering portion 234 can present a plate shape with multiple layers of tabs 233 connected together and having a certain rigidity, rather than a loose and scattered multi-layer foil shape. This facilitates the assembly and connection operations of the tab portion 232 with other components, such as perforation and welding operations. It also makes it less likely for gaps to form in the weld seam formed between the tab portion 232 and other components, which can improve the connection reliability and conductivity of the weld, and make the conductivity of the cell component 23 and the terminal component 25 more stable and reliable.

[0185] Referring again to Figure 21, in some embodiments of this application, at least a portion of the gathering portion 234 is laid on and connected to the inner end face 2511 of the electrode body. In this case, the conductive portion 26 may only include the tab portion 232, and the tab portion 232 is directly connected to the electrode body 251, thus eliminating the need for connecting the conductive component 261 to the tab portion 232. Furthermore, by pre-connecting multiple layers of tabs 233 in the tab portion 232 to form the gathering portion 234, the gathering portion 234 can present a plate-like shape with a certain rigidity, where multiple layers of tabs 233 are connected together, rather than a loose, scattered multi-layered foil shape. This facilitates the connection between the tab portion 232 and the electrode body 251, making the welding of the tab portion 232 and the electrode body 251 more reliable, reducing the likelihood of voids forming in the weld, improving the connection reliability and conductivity at the weld, and making the conductivity between the cell component 23 and the electrode component 25 more stable and reliable. Furthermore, by laying the gathering part 234 on the inner end face of the pole body 251, the gathering part 234 is laid flat and flat, with at least a portion of the gathering part 234 falling on the inner end face of the pole body 251. This prevents damage to the electrode tab 232 due to bending of the gathering part 234, improves conductivity, and facilitates welding of the clamping nozzle to press the gathering part 234, thereby improving the reliability of the connection between the gathering part 234 and the pole body 251.

[0186] According to some embodiments of this application, please refer again to FIG21, the entire gathering portion 234 is laid on the inner end face 2511 of the pole body.

[0187] That is, the inner end face 2511 of the pole body 251 is greater than or equal to the area of ​​the gathering part 234, so that the gathering part 234 can completely fall on the inner end face 2511 of the pole body 251, thereby improving the connection area between the inner end face 2511 of the pole body 251 and the gathering part 234 and improving the current carrying efficiency.

[0188] According to some embodiments of this application, as shown in FIG23, the electrode component 25 includes an electrode body 251, and the battery cell component 23 includes an active material coating portion 231 housed in a receiving cavity 204, and an electrode tab portion 232 connected to the active material coating portion 231. The electrode tab portion 232 is connected to the electrode body 251 through a conductive member 261.

[0189] Therefore, by indirectly connecting the tab 232 and the terminal body 251 through the conductive element 261, the length of the tab 232 can be shortened, improving issues such as wrinkling, bending, and breakage of the tab 233. Furthermore, the shape and material of the conductive element 261 can be flexibly designed to reduce the difficulty of connecting it to the terminal body 251, thus improving the ease of connection. In addition, the perforation operation of the conductive part 26, the connection operation between the conductive part 26 and the terminal component 25 (which can be omitted), and the connection operation between the terminal component 25 and the housing component 21 are all less likely to cause cracking at the connection point between the active material coating part 231 and the tab 232, thereby improving the reliability of the battery cell 20.

[0190] The electrode portion 232 of the battery cell component 23 includes a stacked portion 237 formed by stacking and gathering multiple electrode tabs 233. The multiple electrode tabs 233 in the stacked portion 237 are connected to form a gathered portion 234. That is, the electrode portion 232 includes a gathered portion 234 formed by stacking and connecting multiple electrode tabs 233.

[0191] For example, the laminated portion 237 can be connected to the conductive member 261, thereby eliminating the step of connecting the laminated portion 237 to form the closing portion 234. Alternatively, for example, the multilayer tabs 233 in the laminated portion 237 can be connected to form the closing portion 234 before connecting the closing portion 234 to the conductive member 261, thereby allowing for flexible and diverse design of the structural form of the conductive member 261.

[0192] For example, the conductive element 261 can be connected to the inner end face of the electrode body 251, thereby shortening the length of the conductive element 261. For instance, referring to FIG24, the conductive element 261 may include a second connecting segment 2613, which can be laid on and connected to the inner end face of the electrode body 251, thereby improving the connection reliability and conductivity between the conductive element 261 and the electrode body 251. Alternatively, for example, the conductive element 261 can also be connected to other locations on the electrode body 251, such as pre-embedding the conductive element 261 in the electrode body 251 or passing through the electrode body 251 for connection.

[0193] According to some embodiments of this application, as shown in FIG24, the conductive member 261 includes a first connecting segment 2611, the first connecting segment 2611 includes two clamping portions 2612, and the electrode portion 232 includes an electrode end portion 2321, which is clamped between the two clamping portions 2612 and connected to the clamping portions 2612.

[0194] The tab end 2321 can be either a stacked portion 237 or a gathered portion 234. Thus, the two clamping portions 2612 can be used to limit the tab end 2321, improving the connection reliability of the multiple tab pieces 233 in the tab end 2321. Furthermore, in some examples, by providing two clamping portions 2612, the tab end 2321 clamped between the two clamping portions 2612 can be in the state of a stacked portion 237, eliminating the step of connecting the multiple tab pieces 233 in the stacked portion 237 to form the gathered portion 234, thereby simplifying the processing steps and improving processing efficiency.

[0195] According to some embodiments of this application, please refer again to FIG24. The surface of the end of the electrode body 251 facing the cell component 23 is the inner end face 2511 of the electrode body. The conductive member 261 includes a second connecting segment 2613, which is laid on and connected to the inner end face 2511 of the electrode body. The conductive member 261 is bent at the connection position between the first connecting segment 2611 and the second connecting segment 2613, so that the first connecting segment 2611 is located on the side of the second connecting segment 2613 away from the electrode body 251. One of the clamping portions 2612 supports the tab end 232 on the side away from the electrode body 251. Thus, by supporting the tab 232 with the clamping portion 2612, the redundancy of the tab 232 can be improved, and the risk of short circuit caused by the tab 232 being inserted into the active material coating portion 231 can be reduced. Moreover, the bent conductive component 261 can act as a buffer and support, reducing the risk of the cell component 23 impacting the casing component 21 and improving the reliability of the battery cell 20.

[0196] According to some embodiments of this application, the tab portion 232 includes a gathering portion 234 formed by stacking and connecting multiple layers of tab sheets 233, and the conductive element 261 includes a first connecting segment 2611. The gathering portion 234 is stacked on one side of the first connecting segment 2611 in the thickness direction and connected to the first connecting segment 2611. The first connecting segment 2611 is in the form of a plate, and the thickness direction of the first connecting segment 2611 is consistent with that of the gathering portion 234. The two are stacked along the thickness direction of the first connecting segment 2611, thus simplifying the connection between the gathering portion 234 and the conductive element 261 and improving production efficiency.

[0197] According to some embodiments of this application, the surface of the electrode post body 251 facing the cell component 23 is the inner end face 2511 of the electrode post body. The first connecting section 2611 supports the side of the gathering portion 234 away from the electrode post body 251, so that the gathering portion 234 is sandwiched between the inner end face 2511 of the electrode post body and the first connecting section 2611. Thus, by supporting the gathering portion 234 with the first connecting section 2611, the redundancy of the tab portion 232 can be improved, and the risk of short circuit caused by the tab portion 232 being inserted backward into the active material coating portion 231 can be reduced.

[0198] According to some embodiments of this application, please refer again to Figures 21 and 23. The pole component 25 includes a pole body 251, a transition structure 252 and an insulating sealing structure 253. The transition structure 252 surrounds the pole body 251 and is connected to the cover plate 22 or the housing 24. The insulating sealing structure 253 is insulating and sealingly fitted between the transition structure 252 and the pole body 251.

[0199] The adapter structure 252 surrounds the entire circumference of the terminal body 251 along the mounting hole 249, thereby connecting the terminal body 251 to the second shell wall 243 or connecting the terminal body 251 to the cover plate 22 in the outer peripheral area of ​​the terminal body 251. The insulating and sealing structure 253 insulates the adapter structure 252 from the terminal body 251 and seals the mating position of the adapter structure 252 and the terminal body 251. This isolates the inside and outside of the housing 2 after the adapter structure 252 is connected to the housing 2, reducing the risk of electrolyte leakage from the housing component 21 to the outside of the housing component 21 through the mating position of the adapter structure 252 and the terminal body 251, and reducing the risk of liquids or dust from the outside of the housing component 21 entering the housing component 21 through the mating position of the adapter structure 252 and the terminal body 251, thereby improving the reliability of the battery cell 20.

[0200] In the above technical solution, since the pole piece 25 includes not only the pole piece body 251 but also a transition structure 252 connected to the housing 2, and an insulating sealing structure 253 is provided between the transition structure 252 and the pole piece body 251 to provide insulation and sealing, when installing the pole piece 25 to the housing 2 and connecting the transition structure 252 to the housing 2, no additional sealing element is needed between the transition structure 252 and the housing 2. This eliminates the need to apply significant sealing pressure to meet the compression requirements of the sealing element, thereby reducing the stress on the second housing wall 243 or the cover plate 22 and protecting the housing 2. This helps to reduce the wall thickness of the housing 2 and lower material costs. Furthermore, when the second housing wall 243 is the end of the housing body 24 opposite to the opening, the stress at the connection between the first housing wall 242 and the second housing wall 243, as well as the stress on the first housing wall 242, can be reduced, thus ensuring the reliability of the housing 2 and reducing its wall thickness and cost.

[0201] According to some embodiments of this application, the transition structure 252 is formed as an elongated strip (such as a rectangle or racetrack shape) extending along the length direction of the first shell wall 242, and the outline shape of the electrode body 251 matches the outline shape of the transition structure 252 (such as a rectangle or racetrack shape). As mentioned above, the cell component 23 is connected to the electrode component 25 through the conductive part 26. When the outline shape of the electrode body 251 is formed as an elongated strip that matches the outline shape of the transition structure 252, the area of ​​the electrode body 251 is larger, which is beneficial to increasing the connection area between the conductive part 26 and the electrode body 251, thereby improving the conductivity.

[0202] In other embodiments of this application, referring to FIG25, the adapter structure 252 is formed as an elongated strip (such as a rectangle or racetrack shape) extending along the length direction of the first shell wall 242, and the pole body 251 is located at the center of the length of the adapter structure 252 and is circular. Therefore, the connection point between the adapter structure 252 and the pole body 251 is subjected to uniform force, making it easier to control the compression of the insulating sealing structure 253, thereby improving the reliability of their sealing fit.

[0203] According to some embodiments of this application, the battery cell 20 further includes a terminal post component 25 and a pressure relief device 27. The terminal post component 25 is disposed on the housing component 21 and includes a terminal post body 251. The cell component 23 includes an electrode assembly 235. The tabs 233 of the electrode assembly 235 are connected to form a folded portion 234, which is connected to the terminal post body 251. The pressure relief device 27 is disposed on the housing component 21 and is located on the same side or opposite side of the terminal post component 25.

[0204] For example, the pressure relief device 27 can be an explosion-proof valve installed on the housing component 21, or it can be integrally formed on the thinned area of ​​the housing component 21. Thus, by providing the pressure relief device 27, when the pressure inside the housing component 21 exceeds a preset value, the pressure can be directionally released through the pressure relief device 27, thereby improving the safety and reliability of the battery cell 20.

[0205] For example, referring to Figure 25, the pressure relief device 27 and the terminal post component 25 are located on the same side. Since the terminal post component 25 is located on the second housing wall 243, when the pressure relief device 27 is also located on the second housing wall 243, the pressure relief device 27 and the terminal post component 25 are located on the same side. This simplifies the design of the other housing walls besides the second housing wall 243, and simplifies the structure and processing of the battery cell 20.

[0206] For example, referring to Figure 18, the pressure relief device 27 and the pole member 25 are located on opposite sides. Since the pole member 25 is located on the second shell wall 243, when the pressure relief device 27 is also located on another wall of the housing 2 other than the second shell wall 243, for example, when the pressure relief device 27 is located on the cover plate 22, the pressure relief device 27 and the pole member 25 are located on opposite sides. Therefore, there is no need to consider reducing the volume of the pole member 25 by occupying the space of the second shell wall 243 for the pressure relief device 27, so that the shape and volume of the pole member 25 can be flexibly designed as needed.

[0207] According to some embodiments of this application, this application also provides a battery 100, which includes a battery cell 20 of any of the above embodiments.

[0208] In the above technical solution, the probability of cracking between the cover 112 and the body 24 of the battery cell 20 during use is relatively low, which improves the reliability of the battery 100 and helps to improve the performance of the electrical device.

[0209] According to some embodiments of this application, the battery 100 includes a housing assembly 10, multiple battery cells 20 are housed in the housing assembly 10, the bottom of the housing assembly 10 is a housing bottom plate, the opening 241 of the shell 24 faces the housing bottom plate, and the cover plate 22 is disposed on the bottom of the shell 24; or, the opening 241 of the shell 24 faces away from the housing bottom plate, and the cover plate 22 is disposed on the top of the shell 24.

[0210] For example, cover plate 22 is placed over the bottom of housing 24, and pressure relief device 27 is located on cover plate 22; or, cover plate 22 is placed over the top of housing 24, and pressure relief device 27 is located on the second housing wall 243 opposite to cover plate 22. In this way, if a battery cell 20 experiences thermal runaway, the battery cell 20 can be depressurized from the bottom, eliminating the need for a central venting channel and freeing up space for the battery cell 20, which is beneficial for increasing the energy density of battery 100. Simultaneously, directional pressure relief can be quickly achieved, allowing ejected material to be rapidly discharged in a designated direction through an optimal channel, preventing it from spreading to surrounding cells. For example, cover plate 22 is placed over the top of housing 24, placing the battery cell 20 in an upright position, preventing electrolyte leakage. Therefore, flexible positioning of the battery cell 20 and housing assembly 10 can be achieved.

[0211] According to some embodiments of this application, this application also provides an electrical device, which includes a battery cell 20 of any of the above embodiments; or, includes a battery 100 of any of the above embodiments. The battery cell 20 or the battery 100 is used to provide electrical energy to the electrical device.

[0212] In the above technical solution, the power device uses the battery 100 or battery cell 20. During use, the probability of cracking between the cover 112 and the body 24 of the battery cell 20 is relatively low, which improves the reliability of the battery 100 and helps to improve the performance of the power device.

[0213] The following describes, with reference to the accompanying drawings, six specific embodiments of the present invention, including a battery cell 20, a battery 100 having the battery cell 20, and a vehicle having the battery 100.

[0214] Example 1

[0215] Referring to Figures 3 to 5, the vehicle includes a battery 100, which includes a battery cell 20. The battery cell 20 includes a housing component 21, a cover plate 22, and a cell component 23. The housing component 21 includes a shell 24, the interior of which defines a receiving cavity 204. The shell 24 has an opening 241 and a first shell wall 242 surrounding the circumferential edge of the opening 241. The first shell wall 242 includes at least two sections, of which the section closest to the opening 241 is the first section 2421, and the thickness of the first section 2421 is greater than the thickness of the other sections. The cover plate 22 covers the opening 241 and is connected to the first section 2421. The cell component 23 is disposed in the receiving cavity 204. One end of the shell 24 has an opening 241, and the other end has a second shell wall 243.

[0216] The structure consists of two sections. The section furthest from the opening 241 is the second section 2422, and the section closest to the opening 241 is the first section 2421. The thickness of the first section 2421 is greater than that of the second section 2422, with the first section 2421 having a thickness of 0.7 mm and the second section 2422 having a thickness of 0.3 mm. A step portion 245 is formed between the first section 2421 and the second section 2422. The step portion 245 is located on the outer wall surface of the first shell wall 242 located outside the receiving cavity 204. The inner wall surface of the first shell wall 242 located inside the receiving cavity 204 is flat. The end of the second section 2422 furthest from the opening 241 extends to the second shell wall 243.

[0217] Example 2

[0218] Referring to Figures 6 and 7, the vehicle includes a battery 100, which includes a battery cell 20. The battery cell 20 includes a housing component 21, a cover plate 22, and a cell component 23. The housing component 21 includes a shell 24, the interior of which defines a receiving cavity 204. The shell 24 has an opening 241 and a first shell wall 242 surrounding the circumferential edge of the opening 241. The first shell wall 242 includes at least two sections, of which the section closest to the opening 241 is the first section 2421, and the thickness of the first section 2421 is greater than the thickness of the other sections. The cover plate 22 covers the opening 241 and is connected to the first section 2421. The cell component 23 is disposed in the receiving cavity 204. One end of the shell 24 has an opening 241, and the other end has a second shell wall 243.

[0219] The structure consists of three sections. The section furthest from the opening 241 is the second section 2422, and the section closest to the opening 241 is the first section 2421. The section between the first section 2421 and the second section 2422 is the third section 2423. The thickness of the first section 2421 is 0.7 mm, the thickness of the third section 2423 is 0.5 mm, and the thickness of the second section 2422 is 0.3 mm. Stepped portions 245 are formed between the first section 2421 and the third section 2423, and between the second section 2422 and the third section 2423. The stepped portions 245 are located on the outer wall surface of the first shell wall 242 located outside the receiving cavity 204. The inner wall surface of the first shell wall 242 located inside the receiving cavity 204 is flat. The end of the second section 2422 furthest from the opening 241 extends to the second shell wall 243.

[0220] The design of having the stepped portion 245 located on the outer wall surface outside the receiving cavity 204 simplifies the manufacturing process of the shell 2.

[0221] Example 3

[0222] Referring to Figures 8 and 9, the vehicle includes a battery 100, which includes a battery cell 20. The battery cell 20 includes a housing component 21, a cover plate 22, and a cell component 23. The housing component 21 includes a shell 24, the interior of which defines a receiving cavity 204. The shell 24 has an opening 241 and a first shell wall 242 surrounding the circumferential edge of the opening 241. The first shell wall 242 includes at least two sections, of which the section closest to the opening 241 is the first section 2421, and the thickness of the first section 2421 is greater than the thickness of the other sections. The cover plate 22 covers the opening 241 and is connected to the first section 2421. The cell component 23 is disposed in the receiving cavity 204. One end of the shell 24 has an opening 241, and the other end has a second shell wall 243.

[0223] The structure consists of two sections. The section furthest from the opening 241 is the second section 2422, and the section closest to the opening 241 is the first section 2421. The thickness of the first section 2421 is greater than that of the second section 2422, with the first section 2421 having a thickness of 0.7 mm and the second section 2422 having a thickness of 0.3 mm. A step portion 245 is formed between the first section 2421 and the second section 2422. The step portion 245 is located on the inner wall surface of the first shell wall 242 located inside the receiving cavity 204. The outer wall surface of the first shell wall 242 located outside the receiving cavity 204 is flat. The end of the second section 2422 furthest from the opening 241 extends to the second shell wall 243.

[0224] Example 4

[0225] Referring to Figures 10 and 11, the vehicle includes a battery 100, which includes a battery cell 20. The battery cell 20 includes a housing component 21, a cover plate 22, and a cell component 23. The housing component 21 includes a shell 24, the interior of which defines a receiving cavity 204. The shell 24 has an opening 241 and a first shell wall 242 surrounding the circumferential edge of the opening 241. The first shell wall 242 includes at least two sections, of which the section closest to the opening 241 is the first section 2421, and the thickness of the first section 2421 is greater than the thickness of the other sections. The cover plate 22 covers the opening 241 and is connected to the first section 2421. The cell component 23 is disposed in the receiving cavity 204. One end of the shell 24 has an opening 241, and the other end has a second shell wall 243.

[0226] The structure consists of three sections. The section furthest from the opening 241 is the second section 2422, the section closest to the opening 241 is the first section 2421, and the section between the first and second sections 2421 is the third section 2423. The thickness of the first section 2421 is 0.7 mm, the thickness of the third section 2423 is 0.5 mm, and the thickness of the second section 2422 is 0.3 mm. Stepped portions 245 are formed between the first and third sections 2421 and between the second and third sections 2422. The stepped portions 245 are located on the inner wall surface of the first shell wall 242 inside the receiving cavity 204. The outer wall surface of the first shell wall 242 outside the receiving cavity 204 is flat. The end of the second section 2422 furthest from the opening 241 extends to the second shell wall 243. This design makes the shell 2 less prone to tensile fracture.

[0227] Example 5

[0228] Referring to Figures 12 to 11, the vehicle includes a battery 100, which includes a battery cell 20. The battery cell 20 includes a housing component 21, a cover plate 22, and a cell component 23. The housing component 21 includes a shell 24, the interior of which defines a receiving cavity 204. The shell 24 has an opening 241 and a first shell wall 242 surrounding the circumferential edge of the opening 241. The first shell wall 242 includes at least two sections, of which the section closest to the opening 241 is the first section 2421, and the thickness of the first section 2421 is greater than the thickness of the other sections. The cover plate 22 covers the opening 241 and is connected to the first section 2421. The cell component 23 is disposed in the receiving cavity 204. One end of the shell 24 has an opening 241, and the other end has a second shell wall 243.

[0229] The structure consists of three sections. The section furthest from the opening 241 is the second section 2422, the section closest to the opening 241 is the first section 2421, and the section between the first section 2421 and the second section 2422 is the third section 2423. The thickness of the first section 2421 is 0.7 mm, the thickness of the third section 2423 is 0.5 mm, and the thickness of the second section 2422 is 0.3 mm. Stepped sections 245 are formed between the first section 2421 and the third section 2423, and between the second section 2422 and the third section 2423. The step portion 245 between the first section 2421 and the third section 2423 is located on the outer wall surface of the first shell wall 242 outside the receiving cavity 204, and the step portion 245 between the second section 2422 and the third section 2423 is located on the inner wall surface of the first shell wall 242 inside the receiving cavity 204. The end of the second section 2422 away from the opening 241 extends to the second shell wall 243. With this design, the shell 2 is less prone to tensile fracture.

[0230] Example 6

[0231] Referring to Figures 13 to 15, the vehicle includes a battery 100, which includes a battery cell 20. The battery cell 20 includes a housing component 21, a cover plate 22, and a cell component 23. The housing component 21 includes a shell 24, the interior of which defines a receiving cavity 204. The shell 24 has an opening 241 and a first shell wall 242 surrounding the circumferential edge of the opening 241. The first shell wall 242 includes at least two sections, of which the section closest to the opening 241 is the first section 2421, and the thickness of the first section 2421 is greater than the thickness of the other sections. The cover plate 22 covers the opening 241 and is connected to the first section 2421. The cell component 23 is disposed in the receiving cavity 204. One end of the shell 24 has an opening 241, and the other end has a second shell wall 243.

[0232] The structure consists of three sections. The section furthest from the opening 241 is the second section 2422, the section closest to the opening 241 is the first section 2421, and the section between the first section 2421 and the second section 2422 is the third section 2423. The thickness of the first section 2421 is 0.7 mm, the thickness of the third section 2423 is 0.5 mm, and the thickness of the second section 2422 is 0.3 mm. Stepped sections 245 are formed between the first section 2421 and the third section 2423, and between the second section 2422 and the third section 2423. The step portion 245 between the first section 2421 and the third section 2423 is located on the inner wall surface of the first shell wall 242 inside the receiving cavity 204, and the step portion 245 between the second section 2422 and the third section 2423 is located on the outer wall surface of the first shell wall 242 outside the receiving cavity 204. The end of the second section 2422 away from the opening 241 extends to the second shell wall 243. With this design, the shell 2 is less prone to tensile fracture.

[0233] The casing 2 of the battery cell 20 in this embodiment can alleviate the contradiction between high energy density and high casing 2 strength and fatigue life in related technologies, significantly improving energy density while enhancing product safety and reliability. The battery cell 20 in this embodiment increases the thickness at the welding point between the casing component 21 and the cover plate 22, while still using a 0.3mm thick casing 2 in the portion accommodating the cell component 23, to ensure high energy density.

[0234] In this embodiment, the casing component 21 is not of uniform thickness; its thickness is adjusted according to the design specifications of the battery cell 20. For example, the portion accommodating the cell component 23 is thinned to meet the requirements for increased energy density and weight reduction; the welding portion of the opening 241 is thickened to meet the requirements for welding assembly and increased strength. Thus, this application can significantly improve energy density while reducing the weight of mechanical components and enhancing the safety and reliability of the casing 2.

[0235] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0236] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery cell, wherein, include: A housing component includes a housing body, the interior of which defines a receiving cavity, the housing body having an opening and a first housing wall surrounding a circumferential edge of the opening, the first housing wall including at least two sections, the section closest to the opening being a first section, the thickness of the first section being greater than the thickness of the other sections; A cover plate is provided over the opening and is connected to the first section; The battery cell component is disposed within the receiving cavity.

2. The battery cell of claim 1, wherein, The at least two sections are multiple, and the thickness of the multiple sections decreases sequentially in the direction from the opening toward the inside of the shell.

3. The battery cell of claim 2, wherein, The thickness difference between any two adjacent segments is T, where 0 mm < T ≤ 0.2 mm.

4. The battery cell of any one of claims 1 to 3, wherein, The second segment is the one furthest from the opening among the at least two segments. The second segment has a starting edge close to the first segment, and the first segment has a terminal edge close to the starting edge. The distance between the terminal edge and the starting edge is L, where 6mm ≤ L ≤ 20mm.

5. The battery cell of claim 4, wherein, 6mm≤L≤10mm.

6. The battery cell of any one of claims 1 to 5, wherein, The opening is formed at one end of the opposite ends of the shell, and a second shell wall is formed at the other end; The second segment is the one furthest from the opening among the at least two segments. The thickness of the second segment is less than the thickness of the other segments. The end of the second segment furthest from the opening extends to the second shell wall.

7. The battery cell of any one of claims 1 to 6, wherein, The thickness of the first section is H1, where 0.5mm < H1 ≤ 0.9mm.

8. The battery cell of claim 7, wherein, The second segment is the one furthest from the opening among the at least two segments, and the thickness of the second segment is H2, wherein 0.1mm ≤ H2 < 0.5mm.

9. The battery cell of claim 8, wherein, The at least two segments are three, and the segment located in the middle of the three is the third segment. The thickness of the third segment is H3, wherein 0.3mm < H3 ≤ 0.7mm.

10. The battery cell of any one of claims 1 to 9, wherein, A first transition chamfer or a first transition fillet is provided between any two adjacent segments.

11. The battery cell of any one of claims 1 to 10, wherein, A step is formed between any two adjacent sections. The step is provided on the inner wall surface of the first shell wall located inside the receiving cavity, and the outer wall surface of the first shell wall located outside the receiving cavity is a plane.

12. The battery cell of any one of claims 1-10, wherein, A step is formed between any two adjacent sections. The step is provided on the outer wall surface of the first shell wall located outside the receiving cavity, and the inner wall surface of the first shell wall located inside the receiving cavity is a plane.

13. The battery cell of any one of claims 1-10, wherein, A stepped portion is formed between any two adjacent sections, the first shell wall is provided on the outer wall surface outside the receiving cavity, and the stepped portion is provided on the inner wall surface inside the receiving cavity.

14. The battery cell of any one of claims 1-13, wherein, The first section has a groove located inside the receiving cavity, and the cover plate has a protrusion at its side end near the edge of the opening, the protrusion being located inside the groove.

15. The battery cell of any one of claims 1-14, wherein, The end of the opening away from the receiving cavity has a second transition chamfer or a second transition fillet.

16. The battery cell of any one of claims 1-15, wherein, The shell has an opening at one end and a second shell wall at the other end. The battery cell also includes a terminal post component, and the cell component is connected to the terminal post component. The second shell wall is provided with a mounting hole, and the pole component is installed on the second shell wall and covers the mounting hole; or, the cover plate is provided with a mounting hole, and the pole component is installed on the cover plate and covers the mounting hole.

17. The battery cell of claim 16, wherein, The electrode component includes an electrode body, and the surface of the electrode body facing the cell component is the inner end face of the electrode body. The cell component is connected to the inner end face of the electrode body through a conductive part.

18. The battery cell of claim 17, wherein, The battery cell component includes an active material coating portion housed in the receiving cavity, and an electrode portion connected to the active material coating portion. The electrode portion includes a gathering portion formed by stacking and connecting multiple layers of electrode sheets. At least a portion of the gathering portion is laid on the inner end face of the electrode body and connected to the inner end face of the electrode body.

19. The battery cell according to claim 16 or 17, wherein, The electrode component includes an electrode body, and the battery cell component includes an active material coating portion housed in the receiving cavity, and an electrode tab portion connected to the active material coating portion. The electrode tab portion is connected to the electrode body via a conductive element.

20. The battery cell according to claim 19, wherein, The conductive component includes a first connecting segment, which includes two clamping portions. The electrode portion includes an electrode end, which is clamped between the two clamping portions and connected to the clamping portions.

21. The battery cell according to claim 20, wherein, The surface of the electrode body facing the cell component is the inner end face of the electrode body. The conductive element includes a second connecting segment, which is laid on the inner end face of the electrode body and connected to the inner end face of the electrode body. The conductive element is bent at the connection position between the first connecting segment and the second connecting segment so that the first connecting segment is located on the side of the second connecting segment away from the electrode body. One of the clamping portions is supported on the side of the tab end away from the electrode body.

22. The battery cell according to claim 19, wherein, The tab portion includes a gathered portion formed by stacking and connecting multiple tab sheets, and the conductive element includes a first connecting segment. The gathered portion is stacked on one side of the first connecting segment in the thickness direction and connected to the first connecting segment.

23. The battery cell according to claim 22, wherein, The surface of the electrode body facing the cell component is the inner end face of the electrode body. The first connecting section is supported on the side of the folding part away from the electrode body, so that the folding part is sandwiched between the inner end face of the electrode body and the first connecting section.

24. The battery cell according to any one of claims 16-23, wherein, The pole component includes a pole body, a transition structure, and an insulating and sealing structure. The transition structure surrounds the pole body and is connected to the cover plate or housing. The insulating and sealing structure is insulating and sealingly fitted between the transition structure and the pole body.

25. The battery cell according to claim 24, wherein, The transition structure is formed as an elongated strip extending along the length of the first shell wall, and the outline shape of the pole body matches the outline shape of the transition structure. Alternatively, the transition structure may be formed as an elongated strip extending along the length of the first shell wall, and the pole body may be located at the center of the length of the transition structure and be circular.

26. The battery cell according to any one of claims 1-25, wherein, Also includes: The electrode component is disposed on the housing component and includes an electrode body. The cell component includes an electrode assembly, and the tabs of the electrode assembly are connected to form a folded portion, which is connected to the electrode body. A pressure relief device is provided on the housing component and is located on the same side or opposite side to the pole component.

27. A battery, wherein, Includes the battery cell as described in any one of claims 1 to 26.

28. The battery according to claim 27, wherein, The battery includes a housing assembly, and the battery cells are multiple and housed in the housing assembly. The bottom of the housing assembly is a housing bottom plate, and the opening of the housing body faces the housing bottom plate. The cover plate is placed on the bottom of the housing body; or, the opening of the housing body faces away from the housing bottom plate, and the cover plate is placed on the top of the housing body.

29. An electrical appliance, wherein, Includes the battery cell as described in any one of claims 1 to 26, or the battery as described in claim 27 or 28.

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