Battery monomer, battery and electric device

Abstract

The utility model relates to the field of batteries, and discloses a single battery, a battery and a power utilization device, the single battery comprises a shell component, the shell component comprises a shell body, a containing cavity is defined in the shell body, the shell body is provided with an opening and a first shell wall surrounding the circumferential edge of the opening, the first shell wall comprises at least two sections, and the first section is provided with a first through hole; the section close to the opening in the at least two sections is the first section, and the thickness of the first section is larger than that of the other sections; the cover plate covers the opening and is connected with the first section; and the battery core component is arranged in the accommodating cavity. The shell body and the shell cover of the single battery are not easy to crack due to breathing fatigue, and the single battery is relatively high in energy density and good in use reliability.

Description

Technical Field

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

[0002] In recent years, new energy vehicles have developed by leaps and bounds. In the field of electric vehicles, power batteries, as the power source of electric vehicles, play an irreplaceable and important role. The battery consists of a box and multiple battery cells contained in the box. Among them, batteries, as core components of new energy vehicles, have high requirements in terms of safety and service life. However, the shell strength of some current battery cells is insufficient, and respiratory fatigue cracking may occur. Utility Model Content

[0003] The embodiments of the present application provide a battery cell, a battery and an electrical device. The shell body and shell cover of the battery cell are not prone to fatigue cracking, and have a high energy density and good reliability.

[0004] In a first aspect, an embodiment of the present application provides a battery cell, comprising: a shell component, comprising a shell body, the interior of the shell body defines a accommodating cavity, the shell body is provided with an opening and a first shell wall surrounding the circumferential edge of the opening, the first shell wall includes at least two sections, the at least two sections closer to the opening is the first section, the thickness of the first section is greater than the thickness of the remaining sections; a cover plate, covering the opening and connected to the first section; a battery cell component, arranged in the accommodating cavity.

[0005] In the above technical solution, by setting a first section with a relatively thick thickness on the first shell wall, and the first section is close to the opening, when the cover plate is connected to the first shell wall to form a shell, the cover plate is connected to the first section with the thickest thickness, and the first section with the thickest thickness has a higher structural strength, is not easy to deform under the action of external force, and is not easy to have the problem of fatigue cracking due to back and forth deformation. At the same time, since the thickness of the first section is thicker, the connection area between the cover plate and the shell body is also larger. In summary, the cover plate and the first section are not easy to separate, the connection stability is better, the fatigue resistance of the shell as a whole is better, and fatigue cracking is not easy to occur; at the same time, the part of the first shell wall away from the opening includes the remaining sections, and the remaining sections are mainly used to define the accommodating cavity for accommodating the battery core components. Therefore, the thickness of the remaining sections can be relatively small, so that the volume of the accommodating cavity is large enough to accommodate the battery core components with a larger volume, and the mass of the shell components will not increase too much, and the energy density of the battery will not decrease too much. From the above, the battery cell of the present application has both good structural strength and high fatigue life, better safety in use, and higher energy density of the battery.

[0006] In some embodiments, at least two sections are multiple, and thicknesses of the multiple sections decrease sequentially in a direction from the opening toward the inner side of the shell body.

[0007] The above technical solution can reduce the possibility of the shell being broken during forming and stretching, and has strong manufacturability. At the same time, the thickness of the section farthest from the opening is the thinnest, which is conducive to increasing the volume of the accommodating cavity, reducing the weight of the shell components, and improving the capacity density of the battery.

[0008] In some embodiments, the thickness difference between any two adjacent sections is T, wherein 0 mm<T≤0.2 mm.

[0009] In the above technical solution, the thickness difference between two adjacent sections will not be too large, the thickness will not change suddenly, the connecting part between the two adjacent sections will not easily break after being bent, and the structural strength of the shell body is good.

[0010] In some embodiments, the second segment is the farthest from the opening among the at least two segments, the second segment has a starting edge close to the first segment, the first segment has a terminal edge close to the starting edge, and the distance between the terminal edge and the starting edge is L, wherein 6mm≤L≤20mm.

[0011] 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 bottom support plate and the insulating sheet.

[0012] In some embodiments, 6 mm ≤ L ≤ 10 mm.

[0013] 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 bottom support plate and the insulating sheet.

[0014] In some embodiments, an opening is formed at one of the two opposite ends of the shell body, and a second shell wall is formed at the other end; the second segment is the farthest from the opening among the 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 farthest from the opening extends to the second shell wall.

[0015] In the above technical solution, the first shell wall and the second shell wall have better integrity, are less prone to cracking, have better sealing, and do not need to consider the issue 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 increase the energy density of the battery.

[0016] In some embodiments, the thickness of the first section is H1, wherein 0.5 mm

[0017] ​In the above technical solution, on the one hand, the connection difficulty when the first section is connected to the cover plate is reduced, which can better meet the connection strength requirements with the cover plate, and the strength of the structure is better. The connection area between the first section and the cover plate is larger, the fatigue resistance of the shell body 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 body will not be too heavy, which is conducive to obtaining a higher battery energy density.

[0018] In some embodiments, the second segment is the segment farthest from the opening among the at least two segments, and the thickness of the second segment is H2, wherein 0.1 mm≤H2<0.5 mm.

[0019] In the above technical solution, on the one hand, the thickness of the second section will not be too small, which can meet the structural strength requirements of the second section, so that the second section is not easy to deform or damage, and has good anti-fatigue and aging performance; on the other hand, the thickness of the second section will not be too thick, so that the second section is lighter, which is conducive to making the battery obtain a higher energy density.

[0020] In some embodiments, the at least two sections are three, the section in the middle of the three sections is the third section, and the thickness of the third section is H3, wherein 0.3 mm<H3≤0.7 mm.

[0021] In the above technical solution, the thickness variation between the first section and the third section and the thickness variation between the second section and the third section will not be too large, the connection between the first section and the third section and the connection between the third section and the second section are not prone to breakage, and at the same time, the structural strength of the third section is also relatively high.

[0022] In some embodiments, a first transition chamfer or a first transition fillet is provided between any two adjacent sections.

[0023] In the above technical solution, on the one hand, there will be no sudden change in thickness between two adjacent sections, and the connection between the two adjacent sections is not prone to breakage; on the other hand, there are no sharp edges on the shell body, and it is not easy to scratch the insulating sheet in the accommodating cavity, and the shell body is not prone to wear, and the shell body is also more manufacturable.

[0024] In some embodiments, a step portion is formed between any two adjacent sections, the inner wall surface of the first shell wall located inside the accommodating cavity is provided with a step portion, and the outer wall surface of the first shell wall located outside the accommodating cavity is a plane.

[0025] In the above technical solution, the risk of the sheet material being stretched and cracked when making the shell body is low, and the yield rate is high; at the same time, the volume of the accommodating cavity is large, and there is a large expansion space when the battery cell components expand, and the shell components are not easily squeezed and deformed.

[0026] In some embodiments, a step portion is formed between any two adjacent sections, the outer wall surface of the first shell wall located outside the accommodating cavity is provided with a step portion, and the inner wall surface of the first shell wall located inside the accommodating cavity is a plane.

[0027] In the above technical solution, the manufacturing process is relatively simple, which can reduce the manufacturing cost.

[0028] In some embodiments, a step portion is formed between any two adjacent sections, and the outer wall surface of the first shell wall located outside the accommodating cavity and the inner wall surface located inside the accommodating cavity are provided with a step portion.

[0029] In the above technical solution, when manufacturing the shell body of this embodiment, the risk of the plate being stretched and cracked is low, and the yield rate is high; at the same time, the manufacturing process is simpler, which can reduce the manufacturing cost.

[0030] In some embodiments, the first section is provided with a groove located on the inner side of the accommodating cavity, and the side end of the cover plate close to the open edge is provided with a protrusion, and the protrusion is arranged in the groove.

[0031] 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 connection or fastener connection can be adopted. After adopting the above connection method, welding connection or fastener connection is performed, and the connection strength is also higher and the connection effect is better. The structure is simple and the connection cost is low. At the same time, the sealing performance of the cover plate to cover the opening is also better.

[0032] In some embodiments, a second transition chamfer or a second transition fillet is formed at one end of the opening away from the accommodating cavity.

[0033] In the above technical solution, when the battery core component is installed into the accommodating cavity, the edge of the open opening is not easy to scratch the battery core component.

[0034] In some embodiments, one of the two opposite ends of the shell body is formed with an opening, and the other end is formed with a second shell wall, and the battery cell further includes a pole component, and the battery cell component is connected to the pole component;

[0035] The second shell wall is provided with a mounting hole, the pole component is mounted on the second shell wall and covers the mounting hole; or the cover plate is provided with a mounting hole, the pole component is mounted on the cover plate and covers the mounting hole.

[0036] In the above technical solution, the pole component is installed on the second shell wall and covers the mounting hole, which can effectively reduce the probability of cracking at the weld between the shell body and the cover plate during the use of the battery and improve the reliability of the battery cell; the pole component is installed on the cover plate and covers the mounting hole, which makes assembly easier.

[0037] In some embodiments, the pole component includes a pole body, a surface of the pole body facing one end of the battery cell component is an inner end surface of the pole body, and the battery cell component is connected to the inner end surface of the pole body via a conductive portion.

[0038] In the above technical solution, the difficulty of assembling and connecting the conductive part and the pole body can be reduced, the processing efficiency can be improved, and it is beneficial to shorten the length of the conductive part, saving materials and costs.

[0039] In some embodiments, the battery core component includes an active material coating portion accommodated in a housing cavity, and a pole ear portion connected to the active material coating portion, the pole ear portion includes a gathered portion formed by stacking and connecting multiple layers of pole ear sheets, at least part of the gathered portion is laid on the inner end surface of the pole body and connected to the inner end surface of the pole body.

[0040] In the above technical solution, the gathering portion is laid on the inner end surface of the pole body so that the gathering portion is flattened and at least part of the gathering portion falls on the inner end surface of the pole body, thereby preventing the pole ear from being damaged due to bending the gathering portion, thereby improving the conductive performance and facilitating the welding nozzle to tighten the gathering portion, thereby improving the connection reliability between the gathering portion and the pole body.

[0041] In some embodiments, the pole component includes a pole body, the battery core component includes an active material coating portion accommodated in the accommodating cavity, and a pole ear portion connected to the active material coating portion, and the pole ear portion is connected to the pole body through a conductive member.

[0042] In the above technical solution, the conductive member can be connected to the inner end surface of the pole body, so that the length of the conductive member can be shortened.

[0043] In some embodiments, the conductive member includes a first connecting section, the first connecting section includes two clamping portions, the pole lug portion includes a pole lug end portion, and the pole lug end portion is clamped between the two clamping portions and connected to the clamping portions.

[0044] In the above technical solution, the two clamping parts can be used to limit the end of the pole lug, thereby improving the connection reliability of the multiple layers of pole lug sheets in the end of the pole lug.

[0045] In some embodiments, the surface of one end of the pole body facing the battery core component is the inner end surface of the pole body, and the conductive member includes a second connecting segment, which is laid on the inner end surface of the pole body and connected to the inner end surface of the pole body, and the conductive member is bent at the connecting 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 pole body, and one of the clamping portions is supported on the side of the pole ear end away from the pole body.

[0046] In the above technical solution, the redundancy of the pole ear can be improved by the clamping part supporting the pole ear, and the risk of short circuit caused by the pole ear being inserted into the active material coating part can be reduced. In addition, the bent conductive part can play a role of buffer support, reducing the risk of the battery core component hitting the shell component and improving the reliability of the battery cell.

[0047] In some embodiments, the pole ear portion includes a gathered portion formed by stacking and connecting multiple pole ear sheets, the conductive member includes a first connecting segment, the gathered portion is stacked on one side of the first connecting segment in a thickness direction and connected to the first connecting segment.

[0048] In the above technical solution, the first connecting section is in the form of a plate, and the thickness direction of the first connecting section is consistent with that of the gathering portion, and the two are overlapped along the thickness direction of the first connecting section, so that the matching mode between the gathering portion and the conductive part is simple, which is conducive to improving production efficiency.

[0049] In some embodiments, the surface of one end of the pole body facing the battery core component is the inner end surface of the pole body, and the first connecting section is supported on the side of the gathering portion away from the pole body, so that the gathering portion is sandwiched between the inner end surface of the pole body and the first connecting section.

[0050] In the above technical solution, the redundancy of the pole ear portion can be improved by supporting the gathered portion through the first connecting section, and the risk of short circuit caused by the inverted insertion of the pole ear portion into the active material coating portion can be reduced.

[0051] In some embodiments, the pole component includes a pole body, a transition structure and an insulating sealing structure, the transition structure surrounds the pole body and is connected to the cover plate or the shell body, and the insulating sealing structure is insulated and sealed between the transition structure and the pole body.

[0052] In the above technical solution, since the pole component includes not only the pole body but also the transition structure connected to the shell, and an insulating sealing structure that plays an insulating and sealing role is arranged between the transition structure and the pole body, when the pole component is installed on the shell and the transition structure is connected to the shell, there is no need to arrange a seal between the transition structure and the shell, and there is no need to apply a large sealing pressure to meet the compression degree of the seal there, so that the force on the second shell wall or the cover plate can be reduced, and the shell is protected, which is beneficial to reduce the wall thickness of the shell and reduce material costs.

[0053] In some embodiments, the transition structure is formed into a long strip extending along the length direction of the first shell wall, and the contour shape of the pole body matches the contour shape of the transition structure; or, the transition structure is formed into a long strip extending along the length direction of the first shell wall, and the pole body is arranged at the length center of the transition structure and is circular.

[0054] In the above technical solution, the connection position between the transition structure and the pole body is evenly stressed, and the compression amount of the insulating sealing structure is easily controlled to improve the reliability of the sealing cooperation between the two.

[0055] In some embodiments, the battery cell also includes: a pole component, the pole component is arranged in the shell component, the pole component includes a pole body, the battery cell component includes an electrode assembly, the pole ear pieces of the electrode assembly are connected to form a retracted portion, and the retracted portion is connected to the pole body; a pressure relief device, the pressure relief device is arranged in the shell component, and is located on the same side or the opposite side as the pole component.

[0056] In the above technical solution, the pressure relief device and the pole component are located on the same side. As a result, the design of the shell walls other than the second shell wall can be simplified, and the structure and processing of the battery cell can be simplified. The pressure relief device and the pole component are located on different sides, so there is no need to consider the space occupied by the pressure relief device in the second shell wall to reduce the volume of the pole component, so that the shape and volume of the pole component can be flexibly designed according to needs.

[0057] In a second aspect, an embodiment of the present application further provides a battery, comprising the battery cell described above.

[0058] In the above technical solution, the probability of cracking between the shell cover and the shell body of the battery cell during use is relatively low, which improves the reliability of the battery and is beneficial to improving the performance of the electrical device.

[0059] In some embodiments, the battery includes a box assembly, a plurality of battery cells are accommodated in the box assembly, the bottom of the box assembly is the box bottom plate, the opening of the shell body faces the box bottom plate, and the cover plate is covered on the bottom of the shell body; alternatively, the opening of the shell body faces away from the box bottom plate, and the cover plate is covered on the top of the shell body.

[0060] In the above technical solution, once a battery cell experiences thermal runaway, the battery cell can release pressure from the bottom and the central exhaust channel design can be cancelled, further freeing up space for the battery cell, which is beneficial to the improvement of battery energy density. At the same time, directional pressure relief can be achieved quickly, and the ejected materials can be quickly discharged in the specified direction and through the optimal channel, and are not easy to spread to the surrounding battery cells.

[0061] In a third aspect, an embodiment of the present application further provides an electrical device, comprising the above-mentioned battery; the battery is used to provide electrical energy.

[0062] In the above technical solution, the probability of cracking between the shell cover and the shell body of the battery cell during use is relatively low, which improves the reliability of the battery and is beneficial to improving the performance of the electrical device. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0064] Figure 1 A schematic diagram of the structure of a vehicle provided in some embodiments of the present application;

[0065] Figure 2 An exploded view of the structure of a battery provided in some embodiments of the present application;

[0066] Figure 3 A first cross-sectional view of a housing component in a battery cell provided in some embodiments of the present application;

[0067] Figure 4 A second cross-sectional view of a housing component in a battery cell provided in some embodiments of the present application;

[0068] Figure 5 for Figure 4 A partial enlarged view of part A;

[0069] Figure 6 A cross-sectional view of a housing component in a battery cell provided in some other embodiments of the present application;

[0070] Figure 7 for Figure 6 A partial enlarged view of part B;

[0071] Figure 8 A cross-sectional view of a housing component in a battery cell provided in some further embodiments of the present application;

[0072] Fig. 9 for Figure 8 A partial enlarged view of part C in the middle;

[0073] Fig.10 A cross-sectional view of a housing component in a battery cell provided in some further embodiments of the present application;

[0074] Fig.11 for Fig.10 A partial enlarged view of part D in the middle;

[0075] Fig.12 A cross-sectional view of a housing component in a battery cell provided in some other embodiments of the present application;

[0076] Fig.13 for Fig.12 A partial enlarged view of part E in the middle;

[0077] Fig.14 A cross-sectional view of a housing component in a battery cell provided in some embodiments of the present application;

[0078] Fig.15 for Fig.14 A partial enlarged view of part F in the middle;

[0079] Fig.16 A schematic diagram of a three-dimensional structure of a shell component in a battery cell provided in some embodiments of the present application;

[0080] Fig.17 Schematic diagram of the processing process of the shell body in some embodiments of the present application;

[0081] Fig.18 It is a structural schematic diagram of the connection process between the cover plate and the first section in some embodiments of the present application;

[0082] Fig.19 for Fig.18 A partial enlarged view of the middle G part;

[0083] Fig. 20 A top view of a battery cell provided for some embodiments of the present application;

[0084] Fig.21 For along Fig. 20 Sectional view along line AA;

[0085] Fig. 22 A cross-sectional view of a battery cell provided for some embodiments of the present application;

[0086] Fig.23 for Fig. 22 A partial enlarged view of

[0087] Fig.24 for Fig.23 A partial enlarged view of the middle H section;

[0088] Fig.25 A schematic diagram of the structure of a battery cell provided in some embodiments of the present application;

[0089] Fig.26 A schematic diagram of the structure of the cell components and the pole components in the battery cell provided in some embodiments of the present application.

[0090] icon:

[0091] Battery cell 20;

[0092] Housing 2; housing component 21; cover plate 22;

[0093] Battery cell component 23;

[0094] Active material coating portion 231; pole ear portion 232; pole ear end portion 2321; pole ear sheet 233;

[0095] Folding portion 234; lamination portion 237; electrode assembly 235; axial section 236 of the cell component;

[0096] Shell 24;

[0097] Opening 241; first shell wall 242; first section 2421; second section 2422;

[0098] The third section 2423; the second shell wall 243; the first transition chamfer 244; the step portion 245;

[0099] Groove 246; protrusion 247; second transition fillet 248; mounting hole 249; accommodating cavity 204;

[0100] Pole component 25;

[0101] Pole body 251; inner end surface 2511 of the pole body; transition structure 252; insulating sealing structure 253;

[0102] Conductive portion 26;

[0103] Conductive member 261; first connecting section 2611; clamping portion 2612; second connecting section 2613;

[0104] Pressure relief device 27; rolled aluminum plate 30; aluminum shell punch 400; aluminum shell die 500; blank holder 600;

[0105] Battery 100; box assembly 10; first part 101; second part 102;

[0106] Controller 200 ; Motor 300 ; Vehicle 1000 . DETAILED DESCRIPTION

[0107] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0108] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as those commonly understood by technicians in the technical field of this application; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary and secondary relationship.

[0109] Reference to "embodiment" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments.

[0110] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "attached" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0111] The term "and / or" in this application is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this application generally indicates that the associated objects before and after are in an "or" relationship.

[0112] In the embodiments of the present application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width and other dimensions of various components in the embodiments of the present application shown in the drawings, as well as the overall thickness, length, width and other dimensions of the integrated device are only exemplary descriptions and should not constitute any limitation to the present application.

[0113] The term "plurality" used in the present application refers to two or more (including two).

[0114] In the present application, the battery cell may include a lithium-ion secondary battery, a lithium-ion primary battery, a lithium-sulfur battery, a sodium-lithium-ion battery, a sodium-ion battery, a magnesium-ion battery or a solid-state battery, etc., and the embodiments of the present application do not limit this. The battery cell may be cylindrical, flat, rectangular or other shapes, etc., and the embodiments of the present application do not limit this.

[0115] The battery cell includes a shell, a battery core component and an electrolyte. The shell is used to contain the battery core component and the electrolyte (in a solid-state battery, it can be a solid electrolyte layer located between the positive and negative electrodes). The battery core component includes at least one electrode assembly, which is composed of a positive electrode sheet, a negative electrode sheet and a separator (this structure can be omitted in a solid-state battery). The electrode assembly can be a winding structure or a stacked structure. The battery cell mainly relies on the movement of metal ions between the positive electrode sheet and the negative electrode sheet to work.

[0116] The positive electrode sheet can generally include a positive electrode current collector and a positive electrode active material layer, the positive electrode active material layer is directly or indirectly coated on the positive electrode current collector, the positive electrode current collector not coated with the positive electrode active material layer protrudes from the positive electrode current collector coated with the positive electrode active material layer, and the positive electrode current collector not coated with the positive electrode active material layer serves as a positive electrode tab sheet. Taking lithium-ion batteries as an example, the material of the positive electrode current collector can be aluminum, and the material of the positive electrode active material layer can be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganese oxide, etc.

[0117] The negative electrode sheet can generally include a negative electrode current collector and a negative electrode active material layer, the negative electrode active material layer is directly or indirectly coated on the negative electrode current collector, the negative electrode current collector not coated with the negative electrode active material layer protrudes from the negative electrode current collector coated with the negative electrode active material layer, and the negative electrode current collector not coated with the negative electrode active material layer serves as a negative electrode tab sheet. The material of the negative electrode current collector can be copper, and the material of the negative electrode 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.

[0118] In recent years, new energy vehicles have developed by leaps and bounds. In the field of electric vehicles, power batteries, as the power source of electric vehicles, play an irreplaceable and important role. The battery consists of a box and multiple battery cells contained in the box. Among them, batteries, as core components of new energy vehicles, have high requirements in terms of safety and performance.

[0119] In the manufacturing of battery cells in the related art, an active material layer is coated on the current collector and then cut to obtain a pole piece consisting of a current collector coated with an active material layer (referred to as an active material coating part) and a current collector not coated with an active material layer (referred to as a pole lug piece), and then the positive and negative pole pieces and the separator are stacked or wound in sequence to obtain an electrode assembly, in which multiple pole lug pieces are stacked to form a pole lug part. The pole lug part is connected to the adapter to form a conductive part, or the pole lug part itself forms a conductive part; the active material coating part and the conductive part form a battery core component. A pole post is provided on the shell of the battery cell. When the battery cell is manufactured, the conductive part is usually welded to the pole post to ensure the normal charging and discharging operation.

[0120] At present, the shell of the battery generally adopts a thin shell structure of 0.3-0.5mm. The wall thickness of the shell is small, the weight is light, and the space occupied is small, which is conducive to the improvement of the battery energy density. However, the assembly is difficult and the fatigue resistance is poor. The joints between the shell body and the cover plate are easily damaged and cracked, resulting in gaps, leading to accidents such as electrolyte leakage and battery failure. For example, the top of the shell body has an opening, the pole is set on the cover plate, the cover plate is covered on the opening and welded to the shell body, and the weld is at the top of the battery cell. However, when the battery cell is assembled into a battery, the bottom of the shell body needs to be fixed, and the poles of adjacent battery cells are connected by conductive components (such as busbars). Since the pole is set on the cover plate, when the battery vibrates or deforms during use, the conductive component will pull the pole, and the pulling force of the conductive component on the pole is easily transmitted to the weld between the cover plate and the shell body, resulting in material fatigue and cracking at the weld between the cover plate and the shell body, affecting the reliability of the battery cell.

[0121] In other related technologies, in order to improve the strength of the shell, the wall thickness of the shell is increased to 0.7mm, which greatly reduces the difficulty of assembly. Material fatigue cracking is not prone to occur at the welds between the cover and the shell, thereby improving the fatigue resistance of the shell. However, at the same time, the mass and volume of the shell are also greatly increased, which reduces the energy density of the battery, which is not conducive to improving the competitiveness of battery products.

[0122] Based on the above considerations, in order to improve the fatigue resistance of the shell, while the mass and volume of the shell will not increase too much, and the battery energy density will not decrease too much, the present application proposes a battery cell, the battery cell includes a shell component, a cover plate and a battery cell component, the shell component includes a shell body, the interior of the shell body defines a accommodating cavity, the shell body is provided with an opening and a first shell wall surrounding the circumferential edge of the opening, the first shell wall includes at least two sections, the first section is close to the opening of the at least two sections, and the thickness of the first section is greater than the thickness of the other sections; the cover plate is covered on the opening and is connected to the first section; the battery cell component is arranged in the accommodating cavity.

[0123] In a battery cell of this structure, by setting a first section with a relatively thick thickness on the first shell wall, and the first section is close to the opening, when the cover plate is connected to the first shell wall to form a shell, the cover plate is connected to the first section with the thickest thickness, and the first section with the thickest thickness has a higher structural strength, is not easy to deform under the action of external force, and is not easy to have the problem of fatigue cracking due to back and forth deformation. At the same time, since the thickness of the first section is thicker, the connection area between the cover plate and the shell body is also larger. In summary, the cover plate and the first section are not easy to separate, the connection stability is better, the fatigue resistance of the shell as a whole is better, and fatigue cracking is not easy to occur; at the same time, the part of the first shell wall away from the opening includes the remaining sections, and the remaining sections are mainly used to define the accommodating cavity for accommodating the battery core components. Therefore, the thickness of the remaining sections can be smaller, so that the volume of the accommodating cavity is large enough to accommodate the battery core components with a larger volume, and the mass of the shell components will not increase too much, and the energy density of the battery will not decrease too much. From the above, the battery cell of the present application has both good structural strength and high fatigue life, better safety in use, and higher energy density of the battery.

[0124] The embodiment of the present application provides an electric device using a battery as a power source, and the electric device may be, but is not limited to, a mobile phone, a tablet, a laptop, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft, etc. Among them, the electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, etc., and the spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0125] For the convenience of description, the following embodiments are described by taking a vehicle 1000 as an example of an electrical device according to an embodiment of the present application.

[0126] Please refer to Figure 1 , Figure 1 A schematic diagram of the structure of a vehicle 1000 provided for some embodiments of the present application. The vehicle 1000 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 100 is provided inside the vehicle 1000, and the battery 100 may be provided at the bottom, head or tail of the vehicle 1000. The battery 100 may be used to power the vehicle 1000, for example, the battery 100 may be used as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300, and the controller 200 is used to control the battery 100 to power the motor 300, for example, for starting, navigating and driving the vehicle 1000.

[0127] In some embodiments of the present application, the battery 100 can not only serve as an operating power source for the vehicle 1000, but also serve as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0128] Please refer to Figure 2 , Figure 2 An exploded view of a battery 100 provided in some embodiments of the present application. The battery 100 includes a housing assembly 10 and a battery cell 20 , wherein the battery cell 20 is accommodated in the housing assembly 10 .

[0129] Among them, the box assembly 10 is used to provide a storage space for the battery cell 20, and the box assembly 10 can adopt a variety of structures. In some embodiments, the box assembly 10 may include a first part 101 and a second part 102, the first part 101 and the second part 102 cover each other, and the first part 101 and the second part 102 jointly define a storage space for accommodating the battery cell 20. The second part 102 may be a hollow structure with one end open, and the first part 101 may be a plate-like structure, and the first part 101 covers the open side of the second part 102, so that the first part 101 and the second part 102 jointly define a storage space; the first part 101 and the second part 102 may also be hollow structures with one side open, and the open side of the first part 101 covers the open side of the second part 102. Of course, the box assembly 10 formed by the first part 101 and the second part 102 can be in a variety of shapes, such as a cylinder, a cuboid, etc.

[0130] The box assembly 10 can prevent liquid or other foreign matter from affecting the charging or discharging of the battery cell 20. Of course, some batteries 100 may not include the box assembly 10 and may be directly installed in the battery installation compartment of the electrical device.

[0131] In the battery 100, there can be multiple battery cells 20, and the multiple battery cells 20 can be connected in series, in parallel, or in mixed connection. Mixed connection means that the multiple battery cells 20 are both connected in series and in parallel. Multiple battery cells 20 can be directly connected in series, in parallel, or in mixed connection, and then the whole formed by the multiple battery cells 20 is accommodated in the box assembly 10; of course, the battery 100 can also be a battery module formed by connecting multiple battery cells 20 in series, in parallel, or in mixed connection, and then multiple battery modules are connected in series, in parallel, or in mixed connection to form a whole, and accommodated in the box assembly 10. The battery 100 may also include other structures, for example, the battery 100 may also include a converging component for realizing electrical connection between multiple battery cells 20.

[0132] Hereinafter, a battery cell 20 according to an embodiment of the present application will be described with reference to the drawings.

[0133] Please refer to Figures 3 to 16 , Figure 3 A first cross-sectional view of a housing component 21 in a battery cell 20 provided in some embodiments of the present application; Figure 4 A second cross-sectional view of a housing component 21 in a battery cell 20 provided in some embodiments of the present application;

[0134] Figure 5 for Figure 4 A partial enlarged view of part A; Figure 6 A cross-sectional view of a housing component 21 in a battery cell 20 provided in some other embodiments of the present application; Figure 7 for Figure 6 A partial enlarged view of part B; Figure 8 A cross-sectional view of a housing component 21 in a battery cell 20 provided in some other embodiments of the present application; Fig. 9 for Figure 8 A partial enlarged view of part C in the middle; Fig.10 A cross-sectional view of a housing component 21 in a battery cell 20 provided in some other embodiments of the present application; Fig.11 for Fig.10 A partial enlarged view of part D in the middle; Fig.12 A cross-sectional view of a housing component 21 in a battery cell 20 provided in some other embodiments of the present application; Fig.13 for Fig.12 A partial enlarged view of part E in the middle; Fig.14 A cross-sectional view of a housing component 21 in a battery cell 20 provided in some embodiments of the present application; Fig.15 for Fig.14 A partial enlarged view of part F in the middle; Fig.16 This is a schematic diagram of the three-dimensional structure of the shell component 21 in the battery cell 20 provided in some embodiments of the present application.

[0135] The battery cell 20 includes a shell component 21, a cover plate 22 and a core component 23. The shell component 21 includes a shell body 24. The interior of the shell body 24 defines a accommodating cavity 204. The shell body 24 is provided with 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. Among the at least two sections, the one close to the opening 241 is a first section 2421. The thickness of the first section 2421 is greater than the thickness of the remaining sections. The cover plate 22 is covered on the opening 241 and connected to the first section 2421. The core component 23 is arranged in the accommodating cavity 204.

[0136] Exemplarily, one end of the shell body 24 has an opening 241, the cover plate 22 covers the opening 241, and the shell body 24 and the cover plate 22 together form a receiving cavity 204. Alternatively, exemplarily, the battery cell 20 may include a shell body 24 and two cover plates 22, both ends of the shell body 24 have openings 241, each opening 241 is covered with a cover plate 22, and the two cover plates 22 and the shell body 24 together form a receiving cavity 204.

[0137] The material of the cover plate 22 and the shell body 24 can be aluminum alloy, steel, aluminum-plastic film, plastic or other materials resistant to electrolyte corrosion, and can be selected according to design requirements in practice.

[0138] Exemplarily, the shell wall of the shell body 24 surrounding the circumferential edge of the opening 241 and on one side or both sides in the width direction of the shell body 24 is formed as a first shell wall 242; or, exemplary, the shell wall of the shell body 24 surrounding the circumferential edge of the opening 241 and on one side or both sides in the length direction of the shell body 24 is formed as the first shell wall 242; or, exemplary, the shell wall of the shell body 24 surrounding the circumferential edge of the opening 241 and on one side or both sides in the width direction of the shell body 24 and the shell wall of the shell body 24 surrounding the circumferential edge of the opening 241 and on one side or both sides in the length direction of the shell body 24 are formed as the first shell wall 242.

[0139] The first shell wall 242 may include 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 include 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 in the direction from the opening 241 to the inside of the shell body 24, the thickness of the remaining sections may decrease in sequence, 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 change irregularly.

[0140] The cover plate 22 is arranged on the opening 241 and is connected to the first section 2421, that is, the cover plate 22 is connected to the thickest section of the shell body 24. The thickest first section 2421 has a higher structural strength and is not easily deformed under the action of external force, and is not prone to fatigue cracking due to back-and-forth deformation. At the same time, since the thickness of the first section 2421 is thicker, the connection area between the cover plate 22 and the first section 2421 is also larger. In summary, the connection strength between the cover plate 22 and the shell body 24 is better, fatigue cracking is not likely to occur, and the structural strength of the shell body 24 is also higher. The thickness of the remaining sections is less than that of the first section 2421. That is to say, the present application sets the portion used to accommodate the battery core component 23 to be thinner, so that the weight of the shell body 24 can be made lighter and the volume of the accommodating cavity 204 of the shell body 24 can be made larger, so as to better meet the requirements of energy density improvement and weight reduction. Specifically, the cover plate 22 can be connected to the first section 2421 by welding, or can be connected to the first section 2421 by fasteners, and the shell body 24 and the cover plate 22 are connected to form the shell body 2.

[0141] According to the battery cell 20 of the embodiment of the present application, by setting a thicker first section 2421 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, and the thickest first section 2421 has a higher structural strength, is not easy to deform under the action of external force, and is not easy to have the problem of fatigue cracking due to back and forth deformation. At the same time, since the thickness of the first section 2421 is thicker, the connection between the cover plate 22 and the first section 2421 The area is larger. In summary, the cover plate 22 and the shell body 24 are not easy to separate, the connection stability is better, the overall fatigue resistance of the shell 2 is better, and fatigue cracking is not easy to occur; at the same time, the part of the first shell wall 242 away from the opening 241 includes the remaining sections, and the remaining sections are mainly used to define the accommodating cavity 204 for accommodating the battery cell component 23. Therefore, the thickness of the remaining sections can be smaller, so that the volume of the accommodating cavity 204 is large enough to accommodate the larger battery cell component 23, and the mass of the shell component 21 will not increase too much, and the energy density of the battery 100 will not decrease too much. From the above, the battery cell 20 of the present application has both good structural strength and high fatigue life, better safety in use, and the energy density of the battery 100 is also high.

[0142] In some embodiments, at least two sections are multiple, and the thicknesses of the multiple sections decrease sequentially in the direction from the opening 241 to the inner side of the shell body 24 .

[0143] The thicknesses of the multiple sections decrease sequentially. In other words, in the direction from the opening 241 to the inner side of the shell body 24, the multiple sections are respectively 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 smaller than that of the first section 2421, the thickness of the fourth section is smaller than that of the third section, and the thickness of the second section 2422 is smaller than that of the Nth section.

[0144] like Figures 3 to 5 , Figure 8 and Fig. 9 As shown, there are two sections, and the thickness of the two sections decreases in sequence in the direction from the opening 241 to the inner side of the shell body 24; Figure 6 , Figure 7 , Figures 10 to 15 As shown, there are three sections, and the thicknesses of the three sections decrease in sequence in the direction from the opening 241 to the inner side of the shell body 24 .

[0145] Among them, the thickness of multiple sections decreases successively, which may include that the thickness change trend of multiple sections is a continuous linear change trend or a continuous nonlinear change trend; or, the thickness change of multiple sections is a discontinuous change trend; or, the thickness change of multiple sections is partly a continuous change trend and partly a discontinuous change trend.

[0146] You can refer to Fig.17 As shown, Fig.17 Schematic diagram of the processing of the shell body 24 in some embodiments of the present application. When processing and forming the shell body 24, firstly, the circumferential edge of the rolled aluminum plate 30 is clamped between the aluminum shell concave die 500 and the blank holder 600, and then the aluminum shell convex die 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.

[0147] In this embodiment, the thickness of multiple sections decreases in the direction from the opening 241 to the inner side of the shell body 24, so that the possibility of the shell 2 being broken during forming and stretching can be reduced, and the manufacturability is strong. At the same time, the thickness of the section farthest from the opening 241 is the thinnest, which is conducive to increasing the volume of the accommodating cavity 204, reducing the weight of the shell component 21, and improving the energy density of the battery 100.

[0148] In some embodiments, the thickness difference between any two adjacent sections is T, wherein 0 mm<T≤0.2 mm.

[0149] For example, the thickness difference between any two adjacent sections can be the same or different. The thickness difference between any two adjacent sections can be 0.2 mm, 0.18 mm, 0.16 mm, 0.14 mm, 0.12 mm, 0.1 mm, 0.08 mm, 0.06 mm, 0.04 mm, 0.02 mm or any value between any two values.

[0150] In this way, the thickness difference between two adjacent sections will not be too large, the thickness will not change suddenly, the connecting part between the two adjacent sections will not easily break after being bent, and the structural strength of the shell body 24 will be better.

[0151] In some embodiments, reference may be made to Figure 5 , Figure 7 , Fig. 9 , Fig.11 , Fig.13 , Fig.15 Among at least two sections, the one farthest from the opening 241 is the second section 2422, the second section 2422 has a starting edge close to the first section 2421, the first section 2421 has a terminal edge close to the starting edge, and the distance between the terminal edge and the starting edge is L, wherein 6mm≤L≤20mm.

[0152] 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 them. In practice, the distance between the terminal edge and the starting edge can be adjusted according to demand.

[0153] It should be noted that the space defined by the first section 2421 and located inside the accommodating cavity 204 is usually used to accommodate the cover plate 22, the space defined by the second section 2422 and located inside the accommodating cavity 204 is usually used to accommodate the electrode assembly 235, and the space defined by the section between the second section 2422 and the first section 2421 and located inside the accommodating cavity 204 is used to accommodate the bottom support plate and the insulating sheet in the battery cell 20. The bottom support plate is used to resist the extrusion force when the battery cell 20 is squeezed, so as to reduce the risk of the electrode assembly 235 being squeezed; the insulating sheet is used to cover the outside of the electrode assembly 235, so that the electrode assembly 235 and the shell body 24 are insulated. The distance between the terminal edge and the starting edge is within this range, and sufficient space for accommodating the bottom support plate and the insulating sheet can be defined. In addition, the distance between the terminal edge and the starting edge is within the range, that is, the minimum distance between the first section 2421 and the second section 2422 is within the range. In this way, the thickness change between the first section 2421 and the second section 2422 has a larger gradual change space, is less prone to sudden changes, and has better structural strength.

[0154] In some embodiments, reference may be made to Figure 5 , Figure 7 , Fig. 9 , Fig.11 , Fig.13 , Fig.15 Among at least two sections, the one farthest from the opening 241 is the second section 2422, the second section 2422 has a starting edge close to the first section 2421, the first section 2421 has a terminal edge close to the starting edge, and the distance between the terminal edge and the starting edge is L, 6mm≤L≤10mm.

[0155] For example, the distance between the terminal edge and the starting edge can be 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, or any value between any two of these values. In practice, the distance between the terminal edge and the starting edge can be adjusted according to demand.

[0156] It should be noted that the space defined by the first section 2421 and located inside the accommodating cavity 204 is usually used to accommodate the cover plate 22, the space defined by the second section 2422 and located inside the accommodating cavity 204 is usually used to accommodate the electrode assembly 235, and the space defined by the section between the second section 2422 and the first section 2421 and located inside the accommodating cavity 204 can be used to accommodate the bottom support plate and the insulating sheet in the battery cell 20. The bottom support plate is used to resist the extrusion force when the battery cell 20 is squeezed, so as to reduce the risk of the electrode assembly 235 being squeezed; the insulating sheet is used to cover the outside of the electrode assembly 235, so that the electrode assembly 235 and the shell body 24 are insulated. The distance between the terminal edge and the starting edge is within this range, and sufficient space for accommodating the bottom support plate and the insulating sheet can be defined. In addition, the distance between the terminal edge and the starting edge is within the range, that is, the minimum distance between the first section 2421 and the second section 2422 is within the range, so that the thickness change between the first section 2421 and the second section 2422 has a larger gradual space, the thickness does not change suddenly, and the structural strength is better.

[0157] In some embodiments, reference may be made to Figure 5 , Figure 7 , Fig. 9 , Fig.11 , Fig.13 , Fig.15 An opening 241 is formed at one of the two opposite ends of the shell body 24, and a second shell wall 243 is formed at the other end; the second section 2422 is the farthest from the opening 241 among the at least two sections, and the thickness of the second section 2422 is less than that of the other sections, and the end of the second section 2422 away from the opening 241 extends to the second shell wall 243.

[0158] Specifically, the space defined by the second shell wall 243 and the second section 2422 is used to accommodate the electrode assembly 235, and the second shell wall 243 and the first shell wall 242 are integrally formed. In this way, the first shell wall 242 and the second shell wall 243 have better integrity, are less prone to cracking, have better sealing, and do not need to consider issues related to 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.

[0159] In some embodiments, reference may be made to Figure 5 , Figure 7 , Fig. 9 , Fig.11 , Fig.13 , Fig.15 , the thickness of the first section 2421 is H1, wherein 0.5 mm

[0160] ​That is, the thickness of the first section 2421 is 0.7±0.2 mm, and the thickness of the first section 2421 is not equal to the thickness of the second section 2422. For example, the thickness of the first section 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 values.

[0161] The thickness of the first section 2421 is within this range. On the one hand, the connection difficulty of the first section 2421 and the cover plate 22 is reduced, and the connection strength requirement with the cover plate 22 can be better met, and the strength of the structure is better. The connection area between the first section 2421 and the cover plate 22 is larger, and the fatigue resistance of the shell body 24 is better, and it is not easy 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 body 24 will not be too heavy, which is conducive to obtaining a higher energy density of the battery 100.

[0162] In some embodiments, reference may be made to Figure 5 , Figure 7 , Fig. 9 , Fig.11 , Fig.13 , Fig.15 Among the at least two sections, the one farthest from the opening 241 is the second section 2422 , and the thickness of the second section 2422 is H2 , wherein 0.1 mm ≤ H2 < 0.5 mm.

[0163] That is, the thickness of the second section 2422 is 0.3±0.2 mm, and the thicknesses of the first section 2421 and the second section 2422 are not equal. For example, the thickness of the second section 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 values.

[0164] The thickness of the second section 2422 is within this range. On the one hand, the thickness of the second section 2422 will not be too small, which can meet the structural strength requirements of the second section 2422, so that the second section 2422 is not prone to deformation and damage, and has good anti-fatigue and aging performance; on the other hand, the thickness of the second section 2422 will not be too thick, so that the second section 2422 is lighter, which is beneficial for the battery 100 to obtain a higher energy density.

[0165] In some embodiments, reference may be made to Figure 7 , Fig.11 , Fig.13 , Fig.15, at least two sections are three, the section in the middle of the three is the third section 2423, the thickness of the third section 2423 is H3, wherein 0.3mm<H3≤0.7mm.

[0166] Exemplarily, 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 is 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.

[0167] The thickness of the third section 2423 is within this range, so that the thickness variation between the first section 2421 and the third section 2423 and the thickness variation between the second section 2422 and the third section 2423 will not be too large, and the connection between the first section 2421 and the third section 2423 and the connection between the third section 2423 and the second section 2422 will not easily break. At the same time, the structural strength of the third section 2423 is also relatively high.

[0168] In some embodiments, reference may be made to Figure 5 , Figure 7 , Fig. 9 , Fig.11 , Fig.13 , Fig.15 A first transition chamfer 244 or a first transition fillet is provided between any two adjacent sections.

[0169] A first transition chamfer 244 or a first transition fillet is set between two adjacent sections. On the one hand, this can prevent a sudden thickness change from occurring between the two adjacent sections, and the connection between the two adjacent sections is less likely to break. On the other hand, the shell body 24 does not have sharp edges, and is less likely to scratch the insulating sheet in the accommodating cavity 204. The shell body is also less likely to be worn, and the shell body is more manufacturable.

[0170] In some embodiments, Figures 8 to 11 As shown, a step portion 245 is formed between any two adjacent sections, the inner wall surface of the first shell wall 242 located inside the accommodating cavity 204 is provided with a step portion 245, and the outer wall surface of the first shell wall 242 located outside the accommodating cavity 204 is a plane.

[0171] That is, the step portion 245 is located on the inner wall surface of the inner side of the accommodating cavity 204. The step portion 245 may be an inclined plane or an arc-shaped surface connecting two adjacent sections on the inner wall surface of the inner side of the accommodating cavity 204. In an embodiment where two sections are provided, one step portion 245 may be provided; in an embodiment where more than two sections are provided, a plurality of step portions 245 are provided accordingly.

[0172] 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 accommodating cavity 204 is flat. In this way, the risk of the plate being stretched and broken when the shell body 24 is manufactured is low, and the yield rate is high. At the same time, the volume of the accommodating cavity 204 is large, and the battery core component 23 has a large expansion space when it expands, and the shell component 21 is not easily squeezed and deformed.

[0173] In some embodiments, Figures 3 to 7 As shown, a step portion 245 is formed between any two adjacent sections, the outer wall surface of the first shell wall 242 located outside the accommodating cavity 204 is provided with a step portion 245, and the inner wall surface of the first shell wall 242 located inside the accommodating cavity 204 is a plane.

[0174] That is, the step portion 245 is located on the outer wall surface outside the accommodating cavity 204, and the step portion 245 may be an inclined plane, or an arc-shaped surface connecting two adjacent sections on the outer wall surface outside the accommodating cavity 204. In an embodiment where two sections are provided, one step portion 245 may be provided; in an embodiment where more than two sections are provided, a plurality of step portions 245 are provided accordingly.

[0175] The step portion 245 is located on the outer wall surface of the first shell wall 242, and the inner wall surface located on the inner side of the accommodating cavity 204 is a plane. In this way, the manufacturing process is relatively simple and the manufacturing cost can be reduced. At the same time, when the battery cells 20 are placed side by side, a cavity is formed between adjacent battery cells 20, and the cavity can be used to accommodate other components to optimize or increase the use effect of the battery 100; or, when the battery cells 20 expand, the stress generated by the squeezing between the battery cells 20 is reduced.

[0176] In some embodiments, reference may be made to Figures 12 to 15 As shown, a step portion 245 is formed between any two adjacent sections, and the outer wall surface of the first shell wall 242 located outside the accommodating cavity 204 and the inner wall surface located inside the accommodating cavity 204 are provided with a step portion 245.

[0177] That is, both the outer wall surface of the first shell wall 242 and the inner wall surface of the first shell wall 242 are provided with a step portion 245. For example, there are three sections, the section closest to the opening 241 is the first section 2421, the section farthest from the opening 241 is the second section 2422, the section between the first section 2421 and the second section 2422 is the third section 2423, the step portion 245 between the first section 2421 and the third section 2423 can be located on the outer wall surface of the outer side of the accommodating cavity 204, and the step portion 245 between the second section 2422 and the third section 2423 can be located on the inner wall surface of the inner side of the accommodating cavity 204; or, the step portion 245 between the first section 2421 and the third section 2423 can be located on the inner wall surface of the inner side of the accommodating cavity 204, and the step portion 245 between the second section 2422 and the third section 2423 can be located on the outer wall surface of the outer side of the accommodating cavity 204.

[0178] When manufacturing the shell body 24 of this embodiment, the risk of the plate being stretched and cracked is low, and the yield rate is high; at the same time, the manufacturing process is simple, which can reduce the manufacturing cost. At the same time, the volume of the accommodating cavity 204 can be increased, and when the battery cell component 23 expands, there is expansion space, and the shell component 21 is not easily squeezed and deformed. In addition, when the battery cells 20 are placed side by side, a chamber can be formed between adjacent battery cells 20, and the chamber can be used to accommodate other components to optimize or increase the use effect of the battery 100; or, when the battery cells 20 expand, the possibility of stress generated by mutual squeezing between the battery cells 20 is reduced.

[0179] In some embodiments, reference may be made to Fig.19 As shown, Fig.19 for Fig.18 A partial enlarged view of the middle G portion. The first section 2421 is provided with a groove 246 located inside the accommodating cavity 204 , and the side end of the cover plate 22 close to the edge of the opening 241 is provided with a protrusion 247 , which is arranged in the groove 246 .

[0180] You can refer to Fig.18 As shown, Fig.18 2 is a schematic diagram of the structure of the connection process between the cover plate 22 and the first section 2421 in some embodiments of the present application. Fig.18 As shown, in the initial state, the end surface 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 surface of the first section 2421 facing away from the second section 2422, and then the flange is bent so that the flange and the end surface of the first section 2421 facing away from the second section 2422 jointly define a groove 246, and at the same time, the protrusion 247 of the cover plate 22 is fixed in the groove 246.

[0181] The above connection method is simple to connect, and the connection method between the cover plate 22 and the first section 2421 is more flexible, for example, welding connection or fastener connection can be adopted. After the above connection method is adopted, welding connection or fastener connection is performed, and the connection strength is higher and the connection effect is better. The structure is simple and the connection cost is low. At the same time, the sealing performance of the cover plate 22 covering the opening 241 is also better.

[0182] In some embodiments, reference may be made to Figure 5 , Figure 7 , Fig. 9 , Fig.11 , Fig.13 , Fig.15 A second transition chamfer or a second transition fillet 248 is formed at one end of the opening 241 away from the accommodating cavity 204 .

[0183] That is, the end of the opening 241 away from the accommodating cavity 204 may be formed with a second transition chamfer; or the end of the opening 241 away from the accommodating cavity 204 may also be formed with a second transition fillet 248. The second transition chamfer or the second transition fillet 248 may cooperate with the side end of the cover plate 22 close to the edge of the opening 241, or may not cooperate with the cover plate 22.

[0184] In the embodiment where the second transition chamfer or the second transition fillet 248 cooperates with the side end of the cover plate 22 near the edge of the opening 241, on the one hand, when the battery cell component 23 is loaded into the accommodating cavity 204, the edge of the opening 241 is not easy to scratch the battery cell component 23; on the other hand, the second transition chamfer or the second transition fillet 248 can play a role in positioning the connection position of the cover plate 22, which is conducive to quickly determining the fixed position of the cover plate 22. At the same time, the connection area between the cover plate 22 and the first section 2421 can also be increased.

[0185] In an embodiment where the second transition chamfer or the second transition fillet 248 does not cooperate with the cover plate 22, for example, the cover plate 22 can be directly connected to the end surface of the first section 2421 facing away from the second section 2422. At this time, the setting of the second transition chamfer or the second transition fillet 248 is beneficial to preventing the edge of the opening 241 from scratching the battery cell component 23 during the process of installing the battery cell component 23 into the accommodating cavity 204.

[0186] According to some embodiments of the present application, reference may be made to Figure 3An opening 241 is formed at one of the two opposite ends of the shell body 24, and a second shell wall 243 is formed at the other end. The battery cell 20 also includes a pole component 25, and the battery cell component 23 is connected to the pole component 25; wherein the second shell wall 243 is provided with a mounting hole 249, and the pole component 25 is mounted on the second shell wall 243 and covered on the mounting hole 249; or, the cover plate 22 is provided with a mounting hole 249, and the pole component 25 is mounted on the cover plate 22 and covered on the mounting hole 249.

[0187] The structure of the housing component 21 is not limited. For example, when the pole component 25 is installed on the cover plate 22, the Fig. 20 and Fig.21 , one end of the shell body 24 has an opening 241, the cover plate 22 covers the opening 241, and the shell body 24 and the cover plate 22 together form a receiving cavity 204. Alternatively, illustratively, the battery cell 20 may include a shell body 24 and two cover plates 22, both ends of the shell body 24 have openings 241, each opening 241 is covered with a cover plate 22, the two cover plates 22 and the shell body 24 together form a receiving cavity 204, and the pole component 25 is mounted on one of the cover plates 22.

[0188] For example, when the pole component 25 is mounted on the second shell wall 243, Fig. 22 and Fig.23 , Fig.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 an accommodating cavity 204 , and the end of the shell body 24 opposite to the opening 241 forms a second shell wall 243 .

[0189] The shell body 24 is an integral piece, that is, the shell body 24 is an integrally molded piece, 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 the first shell wall 242 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, and a cavity is defined between the first shell wall 242 and the second shell wall 243, and the cavity constitutes at least a part of the accommodating cavity 204.

[0190] In the above technical solution, since the battery cell component 23 accommodated in the shell component 21 is connected to the pole component 25 installed on the second shell wall 243, when the battery 100 vibrates or deforms, the pole components 25 connected by the busbar component will be pulled against each other, and since the pole component 25 is arranged on the end wall of the shell body 24 opposite to the opening 241, the force acting on the pole component 25 will be preferentially transmitted to the shell body 24, and will not directly act on the cover plate 22, thereby not only extending the distance for the force to be transmitted to the weld between the shell body 24 and the cover plate 22, but also the shell body 24 will preferentially deform when subjected to force, so as to reduce the force on the weld between the shell body 24 and the cover plate 22, thereby effectively reducing the probability of cracking at the weld between the shell body 24 and the cover plate 22 during the use of the battery 100, and improving the reliability of the battery cell 20.

[0191] Specifically, when the pole component 25 is installed on the second shell wall 243, if the pole component 25 is first installed on the mounting hole 249 of the second shell wall 243 and then the battery cell component 23 is installed into the shell body 24, it will be difficult to connect the battery cell component 23 with the pole component 25. In the embodiment of the present application, the battery cell component 23 and the pole component 25 can be connected first, and then the pole component 25 can be assembled and connected to the shell component 21, thereby satisfying the connection requirements between the battery cell component 23 and the pole component 25, and also satisfying the connection requirements between the pole component 25 and the shell component 21, thereby improving the reliability and processability of the battery cell 20.

[0192] According to some embodiments of this application, please refer to Fig.21 and Fig.23 The pole component 25 includes a pole body 251, and the surface of the pole 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 surface 2511 of the pole body. The cell component 23 is connected to the inner end surface 2511 of the pole body through the conductive portion 26 (e.g., the pole ear portion 232 or the conductive member 261). The cell component 23 includes one or more electrode assemblies 235, and the portion of the current collector coated with the active material layer in the electrode assembly 235 constitutes the active material coating portion 231, and the portion not coated with the active material layer constitutes the pole ear portion 232.

[0193] Therefore, the difficulty of assembling and connecting the conductive part 26 and the pole body 251 can be reduced, the processing efficiency can be improved, and the length of the conductive part 26 can be shortened, saving materials and costs.

[0194] According to some embodiments of this application, please refer to Fig.21 and Fig.23, at least part of the conductive part 26 is laid on the inner end surface 2511 of the pole body. In this way, by laying at least part of the conductive part 26 on the inner end surface of the pole body 251, the at least part of the conductive part 26 is in a flattened state, and the projection of at least part of the conductive part 26 falls on the inner end surface of the pole body 251, which is conducive to improving the connection reliability between the conductive part 26 and the pole body 251, and is conducive to increasing the connection area between the conductive part 26 and the pole body 251, and improving the conductivity.

[0195] Exemplarily, when the battery cell 202 is in an assembled state (eg Fig.21 and Fig.23 As shown in FIG. 2 , the inner end surface of the pole body 251 is parallel to the axial section 236 of the battery core component, and the direction of the pole ear of the battery core component 23 is the direction in which the active material coating portion 231 extends out of the pole ear portion 232, which is perpendicular to the first shell wall 242. Thus, the processing and design of the pole body 251 are convenient.

[0196] According to some embodiments of the present application, when the battery cell 202 is in an assembled state (eg Fig.26 As shown in FIG. 2 , the inner end face 2511 of the pole 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 direction of the pole ear of the cell component 23. The direction of the pole ear of the cell component 23 is the direction in which the active material coating portion 231 extends out of the pole ear portion 232, and the direction is perpendicular to the first shell wall 242. In this way, before laying at least part of the conductive part 26 on the inner end surface of the pole body 251, the pole component 25 can be adjusted to the inner end surface of the pole body 251 parallel to the direction of the pole ear of the battery cell component 23, so as to facilitate laying at least part of the conductive part 26 on the inner end surface of the pole body 251, with a larger welding operation space, and at this time, the connection direction of the two ends of the pole body 251 (i.e., the end close to the battery cell component 23 and the end away from the battery cell component 23) is inclined to the direction of the pole ear of the battery cell component 23, so that after the conductive part 26 is connected to the pole body 251, the pole component 25 is flipped as a whole by less than 90°, which can satisfy the connection direction of the above-mentioned two ends of the pole body 251 parallel to the second shell wall 243 or the cover plate 22, thereby relative to the solution of the inner end surface of the pole body 251 being parallel to the axial section 236 of the battery cell component, the flipping angle of the pole component 25 can be reduced, which is beneficial to shortening the length of the conductive part 26.

[0197] According to some embodiments of the present application, the battery cell component 23 includes an active material coating portion 231 accommodated in the accommodating cavity 204, and a pole ear portion 232 connected to the active material coating portion 231, and the pole ear portion 232 includes a gathering portion 234 formed by stacking and connecting multiple layers of pole ear sheets 233.

[0198] In this way, the multi-layered pole tabs 233 are connected to form a gathered portion 234, so that the multi-layered pole tabs 233 in the gathered portion 234 are electrically conductive, that is, the multi-layered pole tabs 233 in the gathered portion 234 not only present a stacked arrangement, but also have a connected and conductive relationship. Among them, the connection method of the multi-layered pole tabs 233 in the gathered portion 234 is not limited, for example, it can be welding (such as ultrasonic welding, ultrasonic pre-welding and laser welding, resistance welding, pressure melting welding, or brazing, etc.), or perforation connection, or bonding through conductive adhesive, etc. Exemplarily, the multi-layered pole tabs 233 of the same polarity can be ultrasonically welded, and the ultrasonic weld mark formed is the gathered portion 234.

[0199] Exemplarily, the multiple layers of tabs 233 in the gathered portion 234 may belong to the same electrode assembly 235, or may respectively belong to different electrode assemblies 235, that is, several layers of tabs 233 of the same polarity in the same electrode assembly 235 may be connected to form the gathered portion 234, or several layers of tabs 233 of the same polarity in different electrode assemblies 235 may be connected to form the gathered portion 234. Exemplarily, all tabs 233 of the same polarity in the cell component 23 may be connected to form the gathered portion 234, so that the number of gathered portions 234 may be reduced.

[0200] In the above technical scheme, the multi-layer pole ear sheets 233 in the pole ear portion 232 are pre-connected to form a gathered portion 234. The gathered portion 234 can present the form of a plate in which the multi-layer pole ear sheets 233 are connected together and have a certain rigidity, rather than a fluffy multi-layer foil form. This facilitates the assembly and connection operations between the pole ear portion 232 and other components, such as punching operations and welding operations, so that gaps are not easily formed in the welds formed between the pole ear portion 232 and other components, which can improve the connection reliability and conductivity of the welding point, and make the conductivity of the battery cell component 23 and the pole column component 25 more stable and reliable.

[0201] Please refer again Fig.21In some embodiments of the present application, at least part of the gathered portion 234 is laid on the inner end surface 2511 of the pole body and connected to the inner end surface 2511 of the pole body. At this time, the conductive portion 26 may only include the pole ear portion 232, and the pole ear portion 232 is directly connected to the pole body 251, so that the connection step of the conductive member 261 and the pole ear portion 232 can be omitted. Moreover, by pre-connecting the multi-layer pole ear sheets 233 in the pole ear portion 232 to form the gathered portion 234, the gathered portion 234 can present a plate form in which the multi-layer pole ear sheets 233 are connected together and have a certain rigidity, rather than a fluffy and scattered multi-layer foil form, so as to facilitate the matching connection between the pole ear portion 232 and the pole body 251, so that the welding of the pole ear portion 232 and the pole body 251 is more reliable, and it is not easy to form a gap in the weld, which can improve the connection reliability and conductivity of the welding point, and make the conduction of the battery cell component 23 and the pole component 25 more stable and reliable. Moreover, by laying the gathering portion 234 on the inner end surface of the pole body 251, the gathering portion 234 is in a flat and stretched state, and at least a part of the gathering portion 234 falls on the inner end surface of the pole body 251, so that the pole ear portion 232 will not be damaged due to bending the gathering portion 234, thereby improving the conductive performance and facilitating the welding nozzle to tighten the gathering portion 234, thereby improving the connection reliability between the gathering portion 234 and the pole body 251.

[0202] According to some embodiments of this application, please refer to Fig.21 The entirety of the gathered portion 234 is laid on the inner end surface 2511 of the pole body.

[0203] That is, the inner end surface 2511 of the pole body 251 is greater than or equal to the area of ​​the gathered portion 234, so that the gathered portion 234 can completely fall on the inner end surface 2511 of the pole body 251, which is beneficial to increase the connection area between the inner end surface 2511 of the pole body 251 and the gathered portion 234, thereby improving the current passing efficiency.

[0204] According to some embodiments of the present application, reference may be made to Fig.23 As shown, the pole component 25 includes a pole body 251 , and the battery core component 23 includes an active material coating portion 231 accommodated in the accommodating cavity 204 , and a pole ear portion 232 connected to the active material coating portion 231 , and the pole ear portion 232 is connected to the pole body 251 through a conductive member 261 .

[0205] Thus, by indirectly connecting the pole ear portion 232 and the pole body 251 through the conductive member 261, the length of the pole ear portion 232 can be shortened, and the problems of wrinkling, bending and breaking of the pole ear piece 233 can be improved. Moreover, the shape and material of the conductive member 261 can be flexibly designed to reduce the difficulty of connection with the pole body 251 and improve the convenience of connection between the conductive member 261 and the pole body 251. In addition, the perforation operation of the conductive portion 26, the connection operation of the conductive portion 26 and the pole component 25 (which may not be required), and the connection operation of the pole component 25 and the shell component 21 are not likely to cause cracking at the connection position between the active material coating portion 231 and the pole ear portion 232, thereby improving the reliability of the battery cell 20.

[0206] The pole ear portion 232 of the battery cell component 23 includes a stacked portion 237 formed by stacking and gathering multiple pole ear sheets 233 , and the multiple pole ear sheets 233 in the stacked portion 237 are connected to form a gathered portion 234 , that is, the pole ear portion 232 includes a gathered portion 234 formed by stacking and connecting multiple pole ear sheets 233 .

[0207] Exemplarily, the lamination portion 237 can be connected to the conductive member 261, thereby eliminating the step of connecting the lamination portion 237 to form the gathered portion 234. Alternatively, exemplarily, the gathered portion 234 can be connected to the conductive member 261 after the multi-layered tabs 233 in the lamination portion 237 are connected to form the gathered portion 234, so that the structural form of the conductive member 261 can be flexibly and diversely designed.

[0208] For example, the conductive member 261 may be connected to the inner end surface of the pole body 251, so that the length of the conductive member 261 may be shortened. Fig.24 As shown, the conductive member 261 may include a second connecting section 2613, and the second connecting section 2613 may be laid on the inner end surface of the pole body 251 and connected to the inner end surface of the pole body 251, thereby improving the connection reliability and conductive performance of the conductive member 261 and the pole body 251. Alternatively, illustratively, the conductive member 261 may also be connected to other positions of the pole body 251, for example, the conductive member 261 is pre-buried in the pole body 251, or is penetrated in the pole body 251 to be connected to the pole body 251, etc.

[0209] According to some embodiments of the present application, reference may be made to Fig.24 As shown, the conductive member 261 includes a first connecting section 2611 , the first connecting section 2611 includes two clamping portions 2612 , the pole ear portion 232 includes a pole ear end 2321 , and the pole ear end 2321 is clamped between the two clamping portions 2612 and connected to the clamping portions 2612 .

[0210] Among them, the pole ear end 2321 can be a laminated portion 237 or a gathered portion 234. Therefore, the two clamping portions 2612 can be used to limit the pole ear end 2321, thereby improving the connection reliability of the multi-layer pole ear sheet 233 in the pole ear end 2321. In addition, in some examples, by providing two clamping portions 2612, the pole ear end 2321 sandwiched between the two clamping portions 2612 can be in the state of a laminated portion 237, and the step of connecting the multi-layer pole ear sheets 233 in the laminated portion 237 to form the gathered portion 234 can be omitted, thereby simplifying the processing process and improving the processing efficiency.

[0211] According to some embodiments of this application, please refer to Fig.24 , the surface of one end of the pole body 251 facing the battery core component 23 is the inner end face 2511 of the pole body, the conductive member 261 includes a second connecting segment 2613, the second connecting segment 2613 is laid on the inner end face 2511 of the pole body and connected to the inner end face 2511 of the pole 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 pole body 251, and one of the clamping portions 2612 is supported on the side of the pole ear end 2321 away from the pole body 251. Therefore, the support of the pole ear portion 232 by the clamping portion 2612 can improve the redundancy of the pole ear portion 232 and reduce the risk of short circuit caused by the pole ear portion 232 being inserted into the active material coating portion 231. Furthermore, the bent conductive member 261 can play a role of buffer support, thereby reducing the risk of the battery core component 23 colliding with the shell component 21 and improving the reliability of the battery cell 20 .

[0212] According to some embodiments of the present application, the pole ear portion 232 includes a gathered portion 234 formed by stacking and connecting multiple layers of pole ear sheets 233, and the conductive member 261 includes a first connecting segment 2611. The gathered 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 first connecting segment 2611 and the gathered portion 234 have the same thickness direction, and the two are stacked along the thickness direction of the first connecting segment 2611, so that the matching mode of the gathered portion 234 and the conductive member 261 is simple, which is conducive to improving production efficiency.

[0213] According to some embodiments of the present application, the surface of one end of the pole body 251 facing the battery core component 23 is the inner end face 2511 of the pole body, and the first connecting section 2611 is supported on the side of the retracted portion 234 away from the pole body 251, so that the retracted portion 234 is sandwiched between the inner end face 2511 of the pole body and the first connecting section 2611. Thus, the redundancy of the pole ear portion 232 can be improved by supporting the retracted portion 234 with the first connecting section 2611, and the risk of short circuit caused by the pole ear portion 232 being inserted into the active material coating portion 231 can be reduced.

[0214] According to some embodiments of this application, please refer to Fig.21 and Fig.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 shell body 24. The insulating sealing structure 253 is insulated and sealed between the transition structure 252 and the pole body 251.

[0215] The adapter structure 252 surrounds the entire circumference of the pole body 251 along the circumference of the mounting hole 249, so that the adapter structure 252 can play a role in connecting the pole body 251 and the second shell wall 243 or connecting the pole body 251 and the cover plate 22 in the outer peripheral area of ​​the pole body 251. The insulating sealing structure 253 insulates the adapter structure 252 from the pole body 251, and makes the matching position of the adapter structure 252 and the pole body 251 present a sealed state, so as to isolate the inside and outside of the shell 2 after the adapter structure 252 is connected to the shell 2, reduce the risk of the electrolyte in the shell component 21 leaking from the matching position of the adapter structure 252 and the pole body 251 to the outside of the shell component 21, and reduce the risk of liquid or dust outside the shell component 21 entering the shell component 21 from the matching position of the adapter structure 252 and the pole body 251, thereby improving the reliability of the battery cell 20.

[0216] In the above technical solution, since the pole component 25 includes not only the pole body 251 but also the transition structure 252 connected to the shell 2, and an insulating sealing structure 253 is provided between the transition structure 252 and the pole body 251 to play an insulating and sealing role, when the pole component 25 is installed on the shell 2 and the transition structure 252 is connected to the shell 2, there is no need to set a seal between the transition structure 252 and the shell 2, and there is no need to apply a large sealing pressure to meet the compression degree of the seal there, so that the force on the second shell wall 243 or the cover plate 22 can be reduced, and the shell 2 can be protected, which is conducive to reducing the wall thickness of the shell 2 and reducing the material cost. In addition, when the second shell wall 243 is the end of the shell body 24 opposite to the opening, the force on the connection between the first shell wall 242 and the second shell wall 243 can be reduced, and the force on the first shell wall 242 can be reduced, which is conducive to ensuring the reliability of the shell 2 and reducing the wall thickness and cost of the shell 2.

[0217] According to some embodiments of the present application, the adapter structure 252 is formed into a long strip (such as a rectangle or a racetrack) extending along the length direction of the first shell wall 242, and the contour shape of the pole body 251 matches the contour shape of the adapter structure 252 (such as a rectangle or a racetrack). As mentioned above, the battery cell component 23 is connected to the pole component 25 through the conductive part 26. When the contour shape of the pole body 251 is formed into a long strip that matches the contour shape of the adapter structure 252, the area of ​​the pole body 251 is large, which is conducive to increasing the connection area between the conductive part 26 and the pole body 251, thereby improving the conductive performance.

[0218] In some other embodiments of the present application, reference Fig.25 The transition structure 252 is formed into a long strip (such as a rectangle or a racetrack) extending along the length direction of the first shell wall 242, and the pole body 251 is arranged at the length center of the transition structure 252 and is circular. Therefore, the connection position of the transition structure 252 and the pole body 251 is subjected to uniform force, and it is easy to control the compression amount of the insulating sealing structure 253, so as to improve the reliability of the sealing cooperation between the two.

[0219] According to some embodiments of the present application, the battery cell 20 also includes a pole component 25 and a pressure relief device 27. The pole component 25 is arranged on the shell component 21. The pole component 25 includes a pole body 251. The battery cell component 23 includes an electrode assembly 235. The pole ear pieces 233 of the electrode assembly 235 are connected to form a retracted portion 234, and the retracted portion 234 is connected to the pole body 251. The pressure relief device 27 is arranged on the shell component 21 and is located on the same side or the opposite side as the pole component 25.

[0220] For example, the pressure relief device 27 may be an explosion-proof valve installed on the housing component 21, or may be integrally formed in a thinned area of ​​the housing component 21. Thus, by providing the pressure relief device 27, when the pressure in the housing component 21 exceeds a preset value, the pressure may be released in a directional manner through the pressure relief device 27, thereby improving the safety and reliability of the battery cell 20.

[0221] For example, in combination Fig.25 , the pressure relief device 27 is located on the same side as the pole component 25. Since the pole component 25 is provided on the second shell wall 243, when the pressure relief device 27 is also provided on the second shell wall 243, the pressure relief device 27 is located on the same side as the pole component 25. Thus, the design of other shell walls other than the second shell wall 243 can be simplified, and the structure and processing of the battery cell 20 can be simplified.

[0222] For example, in combination Fig.18 , the pressure relief device 27 and the pole component 25 are located on different sides. Since the pole component 25 is arranged on the second shell wall 243, when the pressure relief device 27 is also arranged on other walls of the housing 2 except the second shell wall 243, for example, the pressure relief device 27 is arranged on the cover plate 22, the pressure relief device 27 and the pole component 25 are located on different sides. Therefore, there is no need to consider that the pressure relief device 27 occupies the space of the second shell wall 243 and reduce the volume of the pole component 25, so that the shape and volume of the pole component 25 can be flexibly designed according to needs.

[0223] According to some embodiments of the present application, the present application further provides a battery 100 , and the battery 100 includes the battery cell 20 of any of the above embodiments.

[0224] In the above technical solution, the probability of cracking between the shell cover 112 and the shell body 24 of the battery cell 20 during use is relatively low, which improves the reliability of the battery 100 and is conducive to improving the performance of the electrical device.

[0225] According to some embodiments of the present application, the battery 100 includes a box assembly 10, a plurality of battery cells 20 are accommodated in the box assembly 10, the bottom of the box assembly 10 is the box bottom plate, the opening 241 of the shell 24 faces the box bottom plate, and the cover plate 22 is covered on the bottom of the shell 24; or, the opening 241 of the shell 24 faces away from the box bottom plate, and the cover plate 22 is covered on the top of the shell 24.

[0226] Exemplarily, the cover plate 22 is covered on the bottom of the shell body 24, and the pressure relief device 27 is provided on the cover plate 22; or, the cover plate 22 is covered on the top of the shell body 24, and the pressure relief device 27 is provided on the second shell wall 243 opposite to the cover plate 22. In this way, once a battery cell 20 has thermal runaway, the battery cell 20 can release pressure from the bottom, and the central exhaust channel design can be cancelled, further freeing up space for the battery cell 20, which is beneficial to the improvement of the energy density of the battery 100, and can quickly achieve directional pressure relief, and the ejected material can be quickly discharged in a specified direction and through the optimal channel, and it is not easy to spread to the surrounding battery cells. Exemplarily, the cover plate 22 is covered on the top of the shell body 24, and the battery cell 20 is in an upright state, and the electrolyte is not easy to leak. Therefore, the orientation of the battery cell 20 and the box assembly 10 can be flexibly set.

[0227] According to some embodiments of the present application, the present application further provides an electric device, which includes the battery cell 20 of any of the above embodiments; or includes the battery 100 of any of the above embodiments. The battery cell 20 or the battery 100 is used to provide electric energy for the electric device.

[0228] In the above technical solution, the electrical device adopts the above-mentioned battery 100 or battery cell 20. During use, the probability of cracking between the shell cover 112 and the shell body 24 of the battery cell 20 is relatively low, which improves the reliability of the battery 100 and is conducive to improving the performance of the electrical device.

[0229] The following describes a battery cell 20 , a battery 100 having the battery cell 20 , and a vehicle having the battery 100 according to six specific embodiments of the present invention in conjunction with the accompanying drawings.

[0230] Embodiment 1

[0231] You can refer to Figures 3 to 5 As shown, the vehicle includes a battery 100, the battery 100 includes a battery cell 20, the battery cell 20 includes a shell component 21, a cover plate 22 and a battery cell component 23, the shell component 21 includes a shell body 24, the interior of the shell body 24 defines a accommodating cavity 204, the shell body 24 is provided with 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, at least two sections, the section close to the opening 241 is a first section 2421, the thickness of the first section 2421 is greater than the thickness of the remaining sections; the cover plate 22 is covered on the opening 241 and connected to the first section 2421; the battery cell component 23 is arranged in the accommodating cavity 204; one end of the two opposite ends of the shell body 24 is formed with an opening 241, and the other end is formed with a second shell wall 243.

[0232] There are two sections, the one away from the opening 241 is the second section 2422, and the one close 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, and the thickness of the first section 2421 is 0.7 mm, and the thickness of the second section 2422 is 0.3 mm. A step portion 245 is formed between the first section 2421 and the second section 2422. The step portion 245 is provided on the outer wall surface of the first shell wall 242 located outside the accommodating cavity 204. The inner wall surface of the first shell wall 242 located inside the accommodating cavity 204 is a plane. The end of the second section 2422 away from the opening 241 extends to the second shell wall 243.

[0233] Embodiment 2

[0234] You can refer to Figure 6 to Figure 7 As shown, the vehicle includes a battery 100, the battery 100 includes a battery cell 20, the battery cell 20 includes a shell component 21, a cover plate 22 and a battery cell component 23, the shell component 21 includes a shell body 24, the interior of the shell body 24 defines a accommodating cavity 204, the shell body 24 is provided with 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, at least two sections, the section close to the opening 241 is a first section 2421, the thickness of the first section 2421 is greater than the thickness of the remaining sections; the cover plate 22 is covered on the opening 241 and connected to the first section 2421; the battery cell component 23 is arranged in the accommodating cavity 204; one end of the two opposite ends of the shell body 24 is formed with an opening 241, and the other end is formed with a second shell wall 243.

[0235] There are three sections. The section farthest from the opening 241 is the second section 2422, the section near 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. A step portion 245 is 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 is provided on the outer wall surface of the first shell wall 242 located outside the accommodating cavity 204. The inner wall surface of the first shell wall 242 located inside the accommodating cavity 204 is a plane. The end of the second section 2422 farthest from the opening 241 extends to the second shell wall 243.

[0236] The solution of positioning the step portion 245 on the outer wall surface outside the accommodating cavity 204 can simplify the manufacturing process of the housing 2 .

[0237] Embodiment 3

[0238] You can refer to Figures 8 to 9As shown, the vehicle includes a battery 100, the battery 100 includes a battery cell 20, the battery cell 20 includes a shell component 21, a cover plate 22 and a battery cell component 23, the shell component 21 includes a shell body 24, the interior of the shell body 24 defines a accommodating cavity 204, the shell body 24 is provided with 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, at least two sections, the section close to the opening 241 is a first section 2421, the thickness of the first section 2421 is greater than the thickness of the remaining sections; the cover plate 22 is covered on the opening 241 and connected to the first section 2421; the battery cell component 23 is arranged in the accommodating cavity 204; one end of the two opposite ends of the shell body 24 is formed with an opening 241, and the other end is formed with a second shell wall 243.

[0239] There are two sections, the one away from the opening 241 is the second section 2422, and the one close 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, and the thickness of the first section 2421 is 0.7 mm, and the thickness of the second section 2422 is 0.3 mm. A step portion 245 is formed between the first section 2421 and the second section 2422. The step portion 245 is provided on the inner wall surface of the first shell wall 242 located inside the accommodating cavity 204. The outer wall surface of the first shell wall 242 located outside the accommodating cavity 204 is a plane. The end of the second section 2422 away from the opening 241 extends to the second shell wall 243.

[0240] Embodiment 4

[0241] You can refer to Figure 10 to Figure 11 As shown, the vehicle includes a battery 100, the battery 100 includes a battery cell 20, the battery cell 20 includes a shell component 21, a cover plate 22 and a battery cell component 23, the shell component 21 includes a shell body 24, the interior of the shell body 24 defines a accommodating cavity 204, the shell body 24 is provided with 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, at least two sections, the section close to the opening 241 is a first section 2421, the thickness of the first section 2421 is greater than the thickness of the remaining sections; the cover plate 22 is covered on the opening 241 and connected to the first section 2421; the battery cell component 23 is arranged in the accommodating cavity 204; one end of the two opposite ends of the shell body 24 is formed with an opening 241, and the other end is formed with a second shell wall 243.

[0242] There are three sections, the section far from the opening 241 is the second section 2422, the section close 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. A step portion 245 is 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 is provided on the inner wall surface of the first shell wall 242 located inside the accommodating cavity 204, the outer wall surface of the first shell wall 242 located outside the accommodating cavity 204 is a plane, and the end of the second section 2422 far from the opening 241 extends to the second shell wall 243. This scheme makes the shell 2 not prone to tensile rupture.

[0243] Embodiment 5

[0244] You can refer to Figure 12 to Figure 11 As shown, the vehicle includes a battery 100, the battery 100 includes a battery cell 20, the battery cell 20 includes a shell component 21, a cover plate 22 and a battery cell component 23, the shell component 21 includes a shell body 24, the interior of the shell body 24 defines a accommodating cavity 204, the shell body 24 is provided with 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, at least two sections, the section close to the opening 241 is a first section 2421, the thickness of the first section 2421 is greater than the thickness of the remaining sections; the cover plate 22 is covered on the opening 241 and connected to the first section 2421; the battery cell component 23 is arranged in the accommodating cavity 204; one end of the two opposite ends of the shell body 24 is formed with an opening 241, and the other end is formed with a second shell wall 243.

[0245] There are three sections, the one far from the opening 241 is the second section 2422, the one close 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. A step portion 245 is 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 provided on the outer wall surface of the first shell wall 242 located outside the accommodating cavity 204, the step portion 245 between the second section 2422 and the third section 2423 is provided on the inner wall surface of the first shell wall 242 located inside the accommodating cavity 204, and the end of the second section 2422 away from the opening 241 extends to the second shell wall 243. This solution makes the shell 2 less prone to tensile rupture.

[0246] Embodiment 6

[0247] You can refer to Figures 13 to 15 As shown, the vehicle includes a battery 100, the battery 100 includes a battery cell 20, the battery cell 20 includes a shell component 21, a cover plate 22 and a battery cell component 23, the shell component 21 includes a shell body 24, the interior of the shell body 24 defines a accommodating cavity 204, the shell body 24 is provided with 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, at least two sections, the section close to the opening 241 is a first section 2421, the thickness of the first section 2421 is greater than the thickness of the remaining sections; the cover plate 22 is covered on the opening 241 and connected to the first section 2421; the battery cell component 23 is arranged in the accommodating cavity 204; one end of the two opposite ends of the shell body 24 is formed with an opening 241, and the other end is formed with a second shell wall 243.

[0248] There are three sections, the one far from the opening 241 is the second section 2422, the one close 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. A step portion 245 is 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 provided on the inner wall surface of the first shell wall 242 located inside the accommodating cavity 204, the step portion 245 between the second section 2422 and the third section 2423 is provided on the outer wall surface of the first shell wall 242 located outside the accommodating cavity 204, and the end of the second section 2422 away from the opening 241 extends to the second shell wall 243. This solution makes the shell 2 less prone to tensile rupture.

[0249] The shell 2 of the battery cell 20 of the embodiment of the present application can alleviate the contradiction between high energy density and high shell 2 strength and fatigue life in the related art, significantly improve energy density, and enhance product safety and reliability. The battery cell 20 of the embodiment of the present application increases the thickness of the welding position between the shell component 21 and the cover plate 22, while still using a 0.3mm thick shell 2 in the part accommodating the battery cell component 23 to ensure high energy density.

[0250] The overall thickness of the shell component 21 in the embodiment of the present application is not uniform, and its thickness is adjusted accordingly according to the design indicators of the battery cell 20. For example, the part accommodating the battery cell component 23 is thinned to meet the requirements of energy density improvement and weight reduction; the thickness is thickened at the welding part of the opening 241 to meet the requirements of welding assembly and strength improvement. As a result, the present application can significantly improve the energy density while reducing the weight of the mechanical parts and enhancing the safety and reliability of the shell 2.

[0251] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

[0252] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A battery cell, characterized in that: include: A shell component, comprising a shell body, wherein the interior of the shell body defines a receiving cavity, the shell body is provided with an opening and a first shell wall surrounding a circumferential edge of the opening, the first shell wall comprises at least two sections, the first section of the at least two sections being close to the opening, and the thickness of the first section is greater than the thickness of the remaining sections; a cover plate, covering the opening and connected to the first section; The battery core component is arranged in the accommodating cavity.

2. The battery cell according to claim 1, characterized in that: There are a plurality of at least two sections, and thicknesses of the plurality of sections decrease sequentially in a direction from the opening toward the inner side of the shell body.

3. The battery cell according to claim 2, characterized in that: The thickness difference between any two adjacent sections is T, wherein 0 mm < T ≤ 0.2 mm.

4. The battery cell according to claim 1, characterized in that: The second segment is the farthest from the opening among the at least two segments, the second segment has a starting edge close to the first segment, the first segment has a terminal edge close to the starting edge, and the distance between the terminal edge and the starting edge is L, wherein 6mm≤L≤20mm.

5. The battery cell according to claim 4, characterized in that: 6mm≤L≤10mm.

6. The battery cell according to claim 1, characterized in that: One of the two opposite ends of the shell body is formed with the opening, and the other end is formed with a second shell wall; The second section is the one farthest from the opening among the at least two sections. The thickness of the second section is smaller than that of the other sections. One end of the second section farthest from the opening extends to the second shell wall.

7. The battery cell according to claim 1, characterized in that: The thickness of the first section is H1, wherein 0.5 mm<H1≤0.9 mm.

8. The battery cell according to claim 7, characterized in that: The second section is the section farthest from the opening among the at least two sections, and the thickness of the second section is H2, wherein 0.1 mm≤H2<0.5 mm.

9. The battery cell according to claim 8, characterized in that: The at least two sections are three, and the section in the middle of the three is the third section. The thickness of the third section is H3, wherein 0.3 mm<H3≤0.7 mm.

10. The battery cell according to claim 1, characterized in that: A first transition chamfer or a first transition fillet is provided between any two adjacent sections.

11. The battery cell according to claim 1, characterized in that: A step portion is formed between any two adjacent sections, the inner wall surface of the first shell wall located inside the accommodating cavity is provided with the step portion, and the outer wall surface of the first shell wall located outside the accommodating cavity is a plane.

12. The battery cell according to claim 1, characterized in that: A step portion is formed between any two adjacent sections, the outer wall surface of the first shell wall located outside the accommodating cavity is provided with the step portion, and the inner wall surface of the first shell wall located inside the accommodating cavity is a plane.

13. The battery cell according to claim 1, characterized in that: A step portion is formed between any two adjacent sections, and the outer wall surface of the first shell wall located outside the accommodating cavity and the inner wall surface located inside the accommodating cavity are provided with the step portion.

14. The battery cell according to claim 1, characterized in that: The first section is provided with a groove located on the inner side of the accommodating cavity, and the side end of the cover plate close to the open edge is provided with a protrusion, and the protrusion is arranged in the groove.

15. The battery cell according to claim 1, characterized in that: A second transition chamfer or a second transition fillet is formed at one end of the opening away from the accommodating cavity.

16. The battery cell according to claim 1, characterized in that: One of the two opposite ends of the shell body is formed with the opening, and the other end is formed with a second shell wall, the battery cell further includes a pole component, and the cell component is connected to the pole component; The second shell wall is provided with a mounting hole, the pole component is mounted on the second shell wall and covers the mounting hole; or the cover plate is provided with a mounting hole, the pole component is mounted on the cover plate and covers the mounting hole.

17. The battery cell according to claim 16, characterized in that: The pole component comprises a pole body, a surface of the pole body facing one end of the battery core component is an inner end surface of the pole body, and the battery core component is connected to the inner end surface of the pole body via a conductive portion.

18. The battery cell according to claim 17, characterized in that: The battery core component includes an active material coating portion accommodated in the accommodating cavity, and a pole ear portion connected to the active material coating portion, the pole ear portion includes a gathered portion formed by stacking and connecting multiple layers of pole ear sheets, and at least a portion of the gathered portion is laid on the inner end surface of the pole body and connected to the inner end surface of the pole body.

19. The battery cell according to claim 17, characterized in that: The battery core component includes an active material coating portion accommodated in the accommodation cavity, and a pole ear portion connected to the active material coating portion, and the pole ear portion is connected to the pole body through a conductive member.

20. The battery cell according to claim 19, characterized in that: The conductive member includes a first connecting section, the first connecting section includes two clamping parts, the pole lug portion includes a pole lug end portion, the pole lug end portion is clamped between the two clamping parts and connected to the clamping parts.

21. The battery cell according to claim 20, characterized in that: The conductive member includes a second connecting section, the second connecting section is laid on the inner end surface of the pole body and connected to the inner end surface of the pole body, the conductive member is bent at the connection position between the first connecting section and the second connecting section, so that the first connecting section is located on the side of the second connecting section away from the pole body, and one of the clamping portions is supported on the side of the pole ear end away from the pole body.

22. The battery cell according to claim 19, characterized in that: The pole ear portion includes a gathered portion formed by stacking and connecting multiple pole ear sheets, and the conductive member includes a first connecting segment. The gathered portion is stacked on one side of the first connecting segment in a thickness direction and connected to the first connecting segment.

23. The battery cell according to claim 22, characterized in that: The first connecting section is supported on a side of the gathered portion away from the pole body, so that the gathered portion is sandwiched between the inner end surface of the pole body and the first connecting section.

24. The battery cell according to any one of claims 16 to 23, characterized in that: The pole component comprises a pole body, a transition structure and an insulating sealing structure. The transition structure surrounds the pole body and is connected to the cover plate or the shell body. The insulating sealing structure is insulated and sealed between the transition structure and the pole body.

25. The battery cell according to claim 24, characterized in that: The transition structure is formed into a long strip extending along the length direction of the first shell wall, and the contour shape of the pole body matches the contour shape of the transition structure; Alternatively, the transition structure is formed into a long strip extending along the length direction of the first shell wall, and the pole body is arranged at the length center position of the transition structure and is circular.

26. The battery cell according to claim 1, characterized in that: Also includes: A pole component, the pole component is arranged on the shell component, the pole component includes a pole body, the battery core component includes an electrode assembly, the pole tabs of the electrode assembly are connected to form a retracted portion, and the retracted portion is connected to the pole body; A pressure relief device is provided on the housing component and is located on the same side or on the opposite side as the pole component.

27. A battery, characterized in that: Comprising the battery cell according to any one of claims 1 to 26.

28. The battery according to claim 27, characterized in that The battery comprises a box assembly, the battery cells are multiple and accommodated in the box assembly, the bottom of the box assembly is a box bottom plate, the opening of the shell body faces the box bottom plate, and the cover plate is arranged on the bottom of the shell body; or, the opening of the shell body faces away from the box bottom plate, and the cover plate is arranged on the top of the shell body.

29. An electrical device, characterized in that: The method comprises a battery cell as claimed in any one of claims 1 to 26, or a battery as claimed in claim 27 or 28.

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