Housing assembly, battery cell and battery pack

Abstract

The application provides a shell assembly, an electric core and a battery pack, and relates to the technical field of batteries. The shell assembly comprises a shell and a corrosion-resistant coating; the shell is provided with an anti-explosion notch; and the corrosion-resistant coating is arranged on the outer surface of the shell and covers the anti-explosion notch. By arranging the corrosion-resistant coating on the outer surface of the shell and making the corrosion-resistant coating cover the anti-explosion notch, the shell can be effectively prevented from being corroded in the process of forming the corrosion-resistant layer. In this way, the shell not only has good corrosion resistance due to the corrosion-resistant coating, but also can be prevented from being damaged in the process of forming the corrosion-resistant layer, so as to facilitate improving the consistency of the actual triggering threshold and the design threshold of the anti-explosion valve, and thus the reliability of the electric core can be improved.

Description

Technical Field

[0001] This application relates to the field of battery technology, specifically to a casing assembly, a battery cell, and a battery pack. Background Technology

[0002] In related technologies, a battery cell includes a casing, an electrode assembly disposed within the casing, and terminals extending through the casing. The electrode assembly includes a positive electrode plate, a separator, and a negative electrode plate stacked and wound sequentially. Typically, the positive electrode plate is electrically connected to the positive terminal, and the negative electrode plate is electrically connected to the casing, or to the negative terminal. An explosion-proof valve is provided on the casing to open when the internal pressure of the battery cell abnormally rises to its threshold, forming a pressure relief channel and effectively preventing thermal runaway of the battery cell. To improve the reliability of the explosion-proof valve and control its space occupation, weak structures such as grooves are mainly provided on the casing to form the explosion-proof valve. However, the consistency of these explosion-proof valves is poor, resulting in poor battery cell reliability. Utility Model Content

[0003] Embodiments of this application provide a housing assembly, a battery cell, and a battery pack, which can improve the reliability of the battery cell.

[0004] Firstly, embodiments of this application provide a housing assembly including a housing and an anti-corrosion coating; the housing is provided with explosion-proof grooves; the anti-corrosion coating is disposed on the outer surface of the housing and covers the explosion-proof grooves. Thus, by providing an anti-corrosion coating on the outer surface of the housing and ensuring that the anti-corrosion coating covers the explosion-proof grooves, corrosion of the housing during the molding of the anti-corrosion layer can be effectively prevented. This not only gives the housing good corrosion resistance due to the anti-corrosion coating, but also prevents the explosion-proof grooves from being damaged during the molding of the anti-corrosion layer, thereby improving the consistency between the actual trigger threshold and the design threshold of the explosion-proof valve, and ultimately improving the reliability of the battery cell.

[0005] In some embodiments, explosion-proof grooves are provided on the outer surface of the housing, and the inner walls of the explosion-proof grooves are all connected to the anti-corrosion coating. In this way, the explosion-proof grooves located on the outer surface facilitate visual inspection during the production process and before use, thereby enabling timely detection of defects, damage, or processing problems in the grooves, which helps to improve the reliability of the battery cell.

[0006] In some embodiments, the thickness of the anti-corrosion coating is D, satisfying: 0.002mm ≤ D ≤ 2mm. Thus, by limiting the thickness of the anti-corrosion coating, on the one hand, the coating can be sufficiently thick to provide effective protection for the casing; on the other hand, excessive coating thickness can be avoided, preventing unnecessary increases in the material cost of the battery cell, thereby improving the economic efficiency of the battery cell.

[0007] In some embodiments, the outer surface of the housing includes an electrode welding area and a non-electrode welding area, with explosion-proof markings and an anti-corrosion coating both located in the non-electrode welding area. This avoids the anti-corrosion coating affecting the welding of the housing to other components, thereby improving the reliability of the welding between the housing and other components.

[0008] In some embodiments, the outer casing includes a cylindrical body, a first end plate, and a second end plate. The cylindrical body has an inner hole, and the first and second end plates are respectively connected to both ends of the cylindrical body to close the inner hole. Explosion-proof grooves are provided on the first end plate, and the second end plate has electrode mounting holes and an electrode welding area. This design allows the outer casing to have a larger flat surface at the first end plate, facilitating the stable placement of the battery cell and improving the ease of battery cell assembly and use.

[0009] In some embodiments, the area of ​​the surface of the first end plate facing away from the second end plate is S1, and the area of ​​the first end plate covered by the anti-corrosion coating is S2, satisfying: S2≥30%S1. This ensures that the first end plate has sufficient area for the anti-corrosion coating, thereby guaranteeing the basic anti-corrosion requirements of the first end plate.

[0010] In some embodiments, the cylinder has a height dimension H1 along its axial direction, and the anti-corrosion coating provided on the cylinder has a height dimension H2, satisfying that H2 ≥ 40% of H1. This ensures that the cylinder has sufficient area for the anti-corrosion coating to guarantee the basic anti-corrosion requirements of the cylinder.

[0011] In some embodiments, the anti-corrosion coating on the second end plate is disposed along the periphery of the second end plate; wherein the diameter of the cylinder is D1, and the inner diameter of the anti-corrosion coating on the second end plate is D2, satisfying: D2≥60%D1. This allows the second end plate to have a larger area not covered by the anti-corrosion coating, resulting in a larger electrode welding area, which facilitates increasing the welding area between the battery cell and other components, thereby improving welding reliability.

[0012] In some embodiments, one end face of the cylinder is a cut surface of the cylinder, which is covered by an anti-corrosion coating; wherein, the one of the first end plate and the second end plate closest to the cut surface is held by the cylinder; and / or, the explosion-proof groove extends in a ring shape around the axis of the cylinder. This improves the coverage of the anti-corrosion coating on the cylinder, thereby enhancing the corrosion resistance of the outer shell.

[0013] In some embodiments, the anti-corrosion coating is one of an acrylic coating, an epoxy resin coating, a silicone resin coating, or a ceramic coating; and / or, the peel force of the anti-corrosion coating from the outer shell surface is not less than 0.1 N / cm. This type of coating has a simple application process and forms quickly.

[0014] Secondly, embodiments of this application provide a battery cell including an electrode assembly and the aforementioned housing assembly; the electrode assembly is disposed within the housing. This not only ensures the housing has good corrosion resistance due to the anti-corrosion coating, but also prevents the explosion-proof markings from being damaged during the anti-corrosion coating forming process, thereby improving the consistency between the actual trigger threshold and the design threshold of the explosion-proof valve, and ultimately enhancing the reliability of the battery cell.

[0015] Thirdly, embodiments of this application provide a battery pack including the aforementioned battery cells, wherein there are multiple battery cells electrically connected together. This not only ensures the outer casing has good corrosion resistance due to the anti-corrosion coating, but also prevents the explosion-proof markings from being damaged during the anti-corrosion coating forming process. This facilitates improving the consistency between the actual trigger threshold and the design threshold of the explosion-proof valve, thereby enhancing the reliability of the battery pack.

[0016] The beneficial effects of the embodiments of this application are as follows: In the embodiments of this application, by providing an anti-corrosion coating on the outer surface of the casing and covering the explosion-proof grooves with the anti-corrosion coating, corrosion of the casing during the molding of the anti-corrosion layer can be effectively avoided. This not only gives the casing good corrosion resistance due to the anti-corrosion coating, but also prevents the explosion-proof grooves from being damaged during the molding of the anti-corrosion layer, thereby improving the consistency between the actual trigger threshold and the design threshold of the explosion-proof valve, and ultimately enhancing the reliability of the battery cell. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the battery pack structure provided in an embodiment of this application; Figure 2 This is a schematic diagram of the battery cell structure provided in an embodiment of this application; Figure 3 This is a schematic diagram of the structure of the housing assembly provided in an embodiment of this application; Figure 4 This is a schematic diagram of the internal structure of the housing assembly provided in an embodiment of this application; Figure 5 yes Figure 4 An enlarged schematic diagram of part A in the middle; Figure 6 This is a side view of the housing provided in an embodiment of this application; Figure 7 This is a side view of the housing provided in an embodiment of this application from another direction; Figure 8 yes Figure 4 Enlarged diagram of part B.

[0019] Explanation of reference numerals in the attached figures: 1000 - Battery pack; 201 - Housing; 202 - Housing cover; 100-cell; 10 - Housing assembly; 11-Outer casing; 111-First end plate; 112-Second end plate; 1121-Pole mounting hole; 113-Cylinder body; 1131-Inner hole; 1132-Cutting surface; 1133-Groove; 1134-Convex internal structure; 114 - Sealing ring; 12-Anti-corrosion coating; 13-Explosion-proof markings; 141-Electrode welding area; 142-Non-electrode welding area; 21-Electrode assembly; 22-Electrode post; 23-Lower plastic part; 24-Negative current collector; 25-Positive current collector. Detailed Implementation

[0020] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] Furthermore, it should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of this application. In this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0022] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0023] The terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a product that comprises a list of elements includes not only those elements but also other elements not expressly listed or inherent to such a product.

[0024] Before introducing the embodiments of this application that provide a housing assembly, a battery cell, and a battery pack, the relevant technologies of this application will be introduced first.

[0025] In related technologies, the corrosion resistance of the outer surface of the battery cell casing mainly relies on methods such as nickel plating and passivation to form an anti-corrosion layer. However, deformation of the casing during subsequent manufacturing processes can damage this anti-corrosion layer, exposing the casing surface at the damaged areas and resulting in poor corrosion resistance. Furthermore, during nickel plating for corrosion protection, the weak points on the casing used to form the explosion-proof valve are easily corroded. For example, improper cleaning before nickel plating can lead to corrosion of these weak points. Additionally, electrochemical corrosion can occur during nickel plating due to potential differences, also corroding these weak points. This results in a poor consistency between the actual trigger threshold and the design threshold of the explosion-proof valve, thus reducing the reliability of the battery cell.

[0026] Based on this, embodiments of this application provide a housing assembly, a battery cell, and a battery pack. By employing an operation that is not corrosive to explosion-proof markings to form an anti-corrosion coating on the housing of the battery cell, the explosion-proof valve can be prevented from being damaged by the anti-corrosion layer, thereby improving the consistency between the actual trigger threshold and the design threshold of the explosion-proof valve, and thus improving the reliability of the battery cell.

[0027] The following combination Figures 1 to 8 This application provides a detailed description of a housing assembly 10, a battery cell 100, and a battery pack 1000 provided in the embodiments of this application.

[0028] Please see Figure 1 This application provides a battery pack 1000, which includes the aforementioned battery cells 100. Multiple battery cells 100 are electrically connected. These cells 100 can be connected in series, parallel, or a combination thereof. A combination connection means that some cells 100 are connected in series while others are connected in parallel. Optionally, multiple battery cells 100 can first be connected in series, parallel, or a combination thereof to form battery modules, and then these battery modules can be connected in series, parallel, or a combination thereof to form the battery pack 1000. In other words, multiple battery cells 100 can directly form the battery pack 1000, or they can first be formed into multiple battery modules, and then these battery modules can be combined to form the battery pack 1000.

[0029] It is understood that the battery pack 1000 may also include a housing 201 and a cover 202. The housing 201 and the cover 202 fit together to define an installation cavity. The battery cell 100 is disposed within the installation cavity.

[0030] It is understandable that the battery pack 1000 may also include a power management system, which is also located within the mounting cavity.

[0031] Please see Figure 2 The battery cell 100 provided in the embodiments of this application includes an electrode assembly 21 and a housing assembly 10. The electrode assembly 21 is disposed inside the housing 11.

[0032] It is understood that the electrode assembly 21 includes a positive electrode sheet, a separator, and a negative electrode sheet that are sequentially stacked and wound. The positive electrode sheet includes a positive current collector and a positive active material layer, the positive active material layer being coated on the surface of the positive current collector; the positive current collector includes a positive current collection section and a positive tab, the positive current collection section being coated with the positive active material layer, and the positive tab being uncoated with the positive active material layer. The negative electrode sheet includes a negative current collector and a negative active material layer, the negative active material layer being coated on the surface of the negative current collector; the negative current collector includes a negative current collection section and a negative tab, the negative current collection section being coated with the negative active material layer, and the negative tab being uncoated with the negative active material layer.

[0033] It is understood that the battery cell 100 may also include a positive current collector 25, a negative current collector 24, a lower plastic component 23, and a terminal post 22. The terminal post 22 passes through the outer casing 11 and is sealed to the casing via a sealing element. Both the positive current collector 25 and the negative current collector 24 are disposed within the outer casing 11 and may be located at opposite ends of the electrode assembly 21. Specifically, the positive electrode tab is electrically connected to the terminal post 22 via the positive current collector 25. The negative electrode tab is electrically connected to the outer casing 11 via the negative current collector 24. The lower plastic component 23 is disposed on the side of the positive current collector 25 facing away from the electrode assembly 21 and is used to insulate and isolate the positive current collector 25 from the outer casing 11.

[0034] Please see Figure 3 , Figure 4 and Figure 5 An embodiment of this application provides a housing assembly 10, which includes a housing 11 and an anti-corrosion coating 12. The housing 11 is provided with explosion-proof grooves 13. The anti-corrosion coating 12 is disposed on the outer surface of the housing 11 and covers the explosion-proof grooves 13.

[0035] It is understandable that the anti-corrosion coating 12 can be sprayed onto the outer surface of the housing 11.

[0036] It is understood that the anti-corrosion coating 12 is at least used to prevent the housing 11 from being corroded. The anti-corrosion coating 12 can also be used to prevent the housing 11 from being damaged by scratches.

[0037] For example, the anti-corrosion coating 12 is a material that is not corrosive to the housing 11. For example, the anti-corrosion coating 12 may be an acrylic coating, an epoxy resin coating, an organosilicon resin coating, a ceramic coating, a polyimide coating, a polytetrafluoroethylene coating, or a polyurethane coating.

[0038] It is understood that the outer casing 11 can be a steel casing or an aluminum casing. Exemplarily, the outer casing 11 is a steel casing. Specifically, the outer casing 11 includes a housing, a cover plate, and a sealing ring 114. One end of the housing is closed for mounting the pole post 22. The other end of the housing is used for mounting the cover plate. A sealing ring 114 is provided between the cover plate and the housing. The end of the housing away from the pole post 22 extends towards the axis of the housing to form a flange, and a groove 1133 is provided on the housing to form an inwardly convex structure 1134 protruding towards the axis of the housing. The inwardly convex structure 1134, in conjunction with the flange, clamps both ends of the sealing ring 114 to both sides of the cover plate, thereby fixing the cover plate relative to the housing and sealing the mating parts between the housing and the cover plate through the sealing ring 114.

[0039] The explosion-proof notch 13 can be provided on the outer surface of the housing 11 or on the inner surface of the housing 11. For example, the explosion-proof notch 13 is provided on the outer surface of the housing 11. Specifically, the explosion-proof notch 13 is provided on a planar portion of the housing 11, such as the aforementioned cover plate.

[0040] It is understood that when the explosion-proof groove 13 is provided on the outer surface of the housing 11, the anti-corrosion coating 12 can be connected to the concave surface of the explosion-proof groove 13. When the explosion-proof groove 13 is provided on the inner surface of the housing 11, the explosion-proof groove 13 is provided opposite to the anti-corrosion coating 12 at least along its own depth direction.

[0041] Compared to anti-corrosion layers such as nickel plating that can corrode the outer casing 11, this embodiment provides an anti-corrosion coating 12 on the outer surface of the outer casing 11, covering the explosion-proof grooves 13. This effectively prevents the outer casing 11 from being corroded during the forming process of the anti-corrosion coating. Thus, the outer casing 11 not only has good corrosion resistance due to the anti-corrosion coating 12, but also avoids damage to the explosion-proof grooves 13 during the forming process. This helps improve the consistency between the actual trigger threshold and the design threshold of the explosion-proof valve, thereby enhancing the reliability of the battery cell 100.

[0042] Since the anti-corrosion coating 12 is a coating structure, its thickness is small and its strength is low, so it has no effect on the threshold of triggering the explosion-proof scratch 13 and will not change the threshold of opening the explosion-proof scratch 13 valve.

[0043] Please see Figure 5In some embodiments, explosion-proof grooves 13 are provided on the outer surface of the housing 11, and the inner walls of the explosion-proof grooves 13 are all connected to the anti-corrosion coating 12. In this way, the explosion-proof grooves 13 located on the outer surface facilitate visual inspection during the production process and before use, thereby enabling timely detection of defects, damage or processing problems in the grooves, which is beneficial to improving the reliability of the battery cell 100.

[0044] The inner wall of the explosion-proof groove 13 is connected to the anti-corrosion coating 12, which allows the entire surface of the explosion-proof groove 13 to be connected to the anti-corrosion coating 12, thereby improving the protective effect of the anti-corrosion coating 12 on the explosion-proof groove 13.

[0045] Please see Figure 5 In some embodiments, the thickness of the anti-corrosion coating 12 is D, which satisfies: 0.002mm≤D≤2mm.

[0046] It is understood that the thickness D of the anti-corrosion coating 12 includes, but is not limited to, 0.002mm, 0.051mm, 0.123mm, 0.215mm, 0.336mm, 0.452mm, 0.578mm, 0.689mm, 0.724mm, 0.856mm, 0.943mm, 1.025mm, 1.136mm, 1.247mm, 1.358mm, 1.469mm, 1.572mm, 1.683mm, 1.725mm, 1.836mm, 1.917mm, 1.958mm, 1.979mm, 1.982mm, 1.985mm, 1.988mm, 1.991mm, 1.994mm, 1.997mm, and 2mm.

[0047] In this embodiment, by limiting the thickness of the anti-corrosion coating 12, on the one hand, the anti-corrosion coating 12 can have sufficient thickness to provide effective protection for the outer casing 11; on the other hand, it can avoid the material cost of the battery cell 100 being unnecessarily increased due to the excessive thickness of the anti-corrosion coating 12, thereby improving the economy of the battery cell 100.

[0048] Please see Figure 6 In some embodiments, the outer surface of the housing 11 includes an electrode welding area 141 and a non-electrode welding area 142. Explosion-proof grooves 13 and anti-corrosion coating 12 are both disposed in the non-electrode welding area 142. This prevents the anti-corrosion coating 12 from affecting the welding of the housing 11 to other components, thereby improving the reliability of the welding between the housing 11 and other components.

[0049] It can be understood that the electrode welding area 141 refers to the part used for connecting the positive and negative electrodes between the cells 100 when the housing assembly 10 is applied to the cell 100.

[0050] Please see Figure 4In some embodiments, the outer casing 11 includes a cylindrical body 113, a first end plate 111, and a second end plate 112. The cylindrical body 113 has an inner hole 1131. The first end plate 111 and the second end plate 112 are respectively connected to both ends of the cylindrical body 113 to close the inner hole 1131. Explosion-proof grooves 13 are provided on the first end plate 111. The second end plate 112 is provided with an electrode mounting hole 1121 and an electrode welding area 141. This allows the outer casing 11 to have a larger flat surface at the first end plate 111, which facilitates the stable placement of the battery cell 100 through the first end plate 111, thereby improving the ease of assembly and use of the battery cell 100.

[0051] The second end plate 112 can be integrally formed with the cylinder 113, or it can be welded or snapped onto the cylinder 113.

[0052] Please see Figure 7 In some embodiments, the area of ​​the surface of the first end plate 111 facing away from the second end plate 112 is S1, and the area of ​​the first end plate 111 covered by the anti-corrosion coating 12 is S2, satisfying: S2≥30%S1. In this way, the first end plate 111 can have a sufficient area for the anti-corrosion coating 12 to ensure the basic anti-corrosion requirements of the first end plate 111.

[0053] It is understandable that the maximum value of the area S2 of the part of the first end plate 111 covered by the anti-corrosion coating 12 is S1.

[0054] In some embodiments, the cylinder 113 has a height dimension H1 along its axial direction, and the anti-corrosion coating 12 disposed on the cylinder 113 has a height dimension H2, satisfying that H2 ≥ 40% H1. This ensures that the cylinder 113 has sufficient area for the anti-corrosion coating 12 to guarantee the basic anti-corrosion requirements of the cylinder 113.

[0055] It is understandable that the maximum value of the height H2 of the part of the cylinder 113 covered by the anti-corrosion coating 12 is H1.

[0056] Please see Figure 6 In some embodiments, the anti-corrosion coating 12 disposed on the second end plate 112 is provided along the periphery of the second end plate 112. The diameter of the cylinder 113 is D1, and the inner diameter of the anti-corrosion coating 12 disposed on the second end plate 112 is D2, satisfying: D2 ≥ 60% D1. This allows the second end plate 112 to have a larger area not covered by the anti-corrosion coating 12, resulting in a larger electrode welding area 141 on the second end plate 112. This facilitates increasing the welding area of ​​the battery cell 100 to other components, thereby improving welding reliability.

[0057] It is understood that the maximum inner diameter of the anti-corrosion coating 12 of the second end plate 112 is D1, that is, the second end plate 112 is not provided with an anti-corrosion coating 12.

[0058] Please see Figure 6 In some embodiments, one end face of the cylinder 113 is a cut surface 1132. The cut surface 1132 is covered by an anti-corrosion coating 12. The end plate 111 or the end plate 112 closest to the cut surface 1132 is held by the cylinder 113. This improves the coverage of the anti-corrosion coating 12 on the cylinder 113, thereby enhancing the corrosion resistance of the outer shell 11.

[0059] It can be understood that the cutting surface 1132 refers to the surface of the cut that separates the material of the formed cylinder 113 from other materials.

[0060] For example, if the cylinder 113 is integrally formed with the second end plate 112, then the surface of the cylinder 113 away from the second end plate 112 is the cutting surface 1132.

[0061] For example, the cylinder 113 is a steel shell. The end plate of the cylinder 113 near the cut surface 1132 extends towards the axis of the cylinder 113 to form a flange. A groove 1133 is provided on the cylinder 113 to form an inwardly protruding structure 1134 protruding towards the axis of the shell. The inwardly protruding structure 1134, in conjunction with the flange, clamps both ends of the sealing ring 114 to both sides of the cover plate, thereby fixing the cover plate relative to the shell and sealing the mating parts between the shell and the cover plate through the sealing ring 114. Figure 6 As shown.

[0062] In some embodiments, the explosion-proof notch 13 extends in a ring around the axis of the cylinder 113. This improves the coverage of the explosion-proof notch 13 over the inside of the battery cell, thereby enhancing the reliability of the battery cell.

[0063] Specifically, the anti-corrosion coating 12 on the first end plate 111 extends from the edge of the first end plate 111 toward the center of the first end plate 111 and covers the explosion-proof grooves 13.

[0064] In some embodiments, the anti-corrosion coating 12 is one of an acrylic coating, an epoxy resin coating, an organosilicon resin coating, or a ceramic coating. This type of coating has a simple application process and forms quickly.

[0065] Among them, acrylic coatings have good chemical stability and good resistance to ultraviolet rays, moisture and oxidation environments. They are not easy to age or yellow due to long-term exposure, making them suitable for battery cell 100 applications in outdoor or humid environments.

[0066] The epoxy resin coating has good adhesion and is not easy to peel off. It can adhere tightly to the surface of the outer shell 11 to form a long-lasting protective barrier.

[0067] The silicone resin coating exhibits excellent resistance to high and low temperatures, allowing for long-term use at temperatures ranging from -60℃ to 200℃. The silicone resin coating is also resistant to embrittlement and softening under extreme temperature conditions (such as fast charging of power batteries and low-temperature charging and discharging).

[0068] The main components of ceramic coatings are oxides (such as Al2O3, SiO2) or nitrides (such as Si3N4). Ceramic coatings have good high temperature resistance, fire resistance and insulation.

[0069] In some embodiments, the peeling force of the anti-corrosion coating 12 from the surface of the housing 11 is not less than 0.1 N / cm. This ensures that the anti-corrosion coating 12 and the housing 11 have suitable bonding force, which helps to improve the reliability of the connection between the anti-corrosion coating 12 and the housing 11, thereby improving the corrosion resistance of the housing 11 and thus improving the reliability of the battery cell 100.

[0070] The embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A housing assembly (10), characterized in that, include: The outer casing (11) is provided with explosion-proof grooves (13); An anti-corrosion coating (12) is applied to the outer surface of the housing (11) and covers the explosion-proof grooves (13).

2. The housing assembly (10) according to claim 1, characterized in that, The explosion-proof grooves (13) are provided on the outer surface of the housing (11), and the inner walls of the explosion-proof grooves (13) are all connected to the anti-corrosion coating (12).

3. The housing assembly (10) according to claim 1, characterized in that, The thickness of the anti-corrosion coating (12) is D, which satisfies: 0.002mm≤D≤2mm.

4. The housing assembly (10) according to claim 1, characterized in that, The outer surface of the outer shell (11) includes an electrode welding area (141) and a non-electrode welding area (142), and the explosion-proof groove (13) and the anti-corrosion coating (12) are both provided in the non-electrode welding area (142).

5. The housing assembly (10) according to any one of claims 1-4, characterized in that, The outer shell (11) includes a cylindrical body (113), a first end plate (111) and a second end plate (112). The cylindrical body (113) has an inner hole (1131). The first end plate (111) and the second end plate (112) are respectively connected to the two ends of the cylindrical body (113) to close the inner hole (1131). The explosion-proof groove (13) is provided on the first end plate (111), and the second end plate (112) is provided with a pole mounting hole (1121) and an electrode welding area (141).

6. The housing assembly (10) according to claim 5, characterized in that, The area of ​​the surface of the first end plate (111) facing away from the second end plate (112) is S1, and the area of ​​the part of the first end plate (111) covered by the anti-corrosion coating (12) is S2, satisfying: S2≥30%S1.

7. The housing assembly (10) according to claim 5, characterized in that, In the axial direction of the cylinder (113), the cylinder (113) has a height dimension H1, and the anti-corrosion coating (12) provided on the cylinder (113) has a height dimension H2, satisfying: H2≥40%H1.

8. The housing assembly (10) according to claim 5, characterized in that, The anti-corrosion coating (12) disposed on the second end plate (112) is disposed along the periphery of the second end plate (112); Wherein, the diameter of the cylinder (113) is D1, and the inner diameter of the anti-corrosion coating (12) provided on the second end plate (112) is D2, satisfying: D2≥60%D1.

9. The housing assembly (10) according to claim 5, characterized in that, One end face of the cylinder (113) is the cut surface (1132) of the cylinder (113), and the cut surface (1132) is covered by the anti-corrosion coating (12); wherein, the one of the first end plate (111) and the second end plate (112) closest to the cut surface (1132) is held by the cylinder (113); and / or, The explosion-proof groove (13) extends in a ring around the axis of the cylinder (113).

10. The housing assembly (10) according to any one of claims 1-4, characterized in that, The anti-corrosion coating (12) is one of an acrylic coating, an epoxy resin coating, an organosilicon resin coating, or a ceramic coating; and / or, the peeling force of the anti-corrosion coating (12) from the surface of the outer shell (11) is not less than 0.1 N / cm.

11. A battery cell (100), characterized in that, include: The housing assembly (10) as claimed in any one of claims 1-10; as well as Electrode assembly (21) is disposed within the housing (11).

12. A battery pack (1000), characterized in that, Includes a battery cell (100) as described in claim 11, wherein there are multiple battery cells (100) and the multiple battery cells (100) are electrically connected.

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