Housing structure, battery, battery pack, and electric device

Abstract

The application discloses a shell structure, a battery, a battery pack and an electric equipment. The shell structure comprises a shell, the shell comprises a base layer and a functional layer arranged on at least one side of the base layer in the thickness direction, and the electrical conductivity of the functional layer is less than that of the base layer.

Description

Technical Field

[0001] This application relates to the field of battery technology, specifically to a battery casing structure, a battery, a battery pack, and an electrical device. Background Technology

[0002] Battery casings often employ a Ni-Fe-Ni composite structure (i.e., nickel plating on both sides of an iron layer) to balance corrosion resistance and conductivity. However, during manufacturing or long-term use, this composite structure is prone to defects such as localized nickel layer damage, pinholes, or uneven coverage, exposing the internal iron layer to the electrolyte or external environment. Once exposed, the exposed iron layer is highly susceptible to chemical and electrochemical corrosion, which can lead to casing perforation and electrolyte leakage in severe cases. Simultaneously, iron itself has low conductivity; during high-rate charging and discharging, the iron layer significantly increases the internal resistance of the casing, limiting current flow, causing casing heating, increased energy loss, and even affecting the battery's rate performance and safety. Therefore, Ni-Fe-Ni composite casings suffer from the technical problems of "iron leakage leading to corrosion and insufficient current carrying capacity." Summary of the Invention

[0003] To address at least one of the aforementioned problems, embodiments of this application provide a battery casing structure, a battery, a battery pack, and an electrical device.

[0004] This application provides a battery casing structure. The casing structure includes: a casing, the casing including a base layer in the thickness direction and a functional layer disposed on at least one side of the base layer, the conductivity of the functional layer being less than the conductivity of the base layer.

[0005] In some embodiments, the resistivity of the functional layer at 20°C is ≤1×10⁻⁶. -6 Ω·m.

[0006] In some embodiments, the resistivity of the substrate layer at 20°C is ≤1×10⁻⁶. -7 Ω·m.

[0007] In some embodiments, the ratio k of the resistivity of the functional layer at 20°C to the resistivity of the substrate layer at 20°C satisfies: 1 <k≤1000。

[0008] In some embodiments, the functional layer is at least one selected from stainless steel, zirconium, titanium, titanium alloy, zinc, copper, copper alloy, and nickel alloy.

[0009] In some embodiments, the functional layer includes a first functional layer and a second functional layer. The first functional layer is disposed on the outer surface of the substrate layer. The second functional layer is disposed on the inner surface of the substrate layer. The first functional layer and the second functional layer are made of the same first material, and the substrate layer is made of a second material, wherein the conductivity of the first material is less than the conductivity of the second material.

[0010] In some embodiments, the first functional layer is at least one of a stainless steel layer, a zirconium layer, a titanium layer, a titanium alloy layer, a zinc layer, a copper layer, a copper alloy layer, and a nickel alloy layer.

[0011] In some embodiments, the second functional layer is at least one of a stainless steel layer, a zirconium layer, a titanium layer, a titanium alloy layer, a zinc layer, a copper layer, a copper alloy layer, and a nickel alloy layer.

[0012] In some embodiments, the substrate layer is at least one of a gold layer, a copper layer, a tungsten layer, an aluminum layer, a silver layer, a copper alloy layer, an aluminum alloy layer, or a silver alloy layer.

[0013] In some embodiments, the thickness T1 of the first functional layer and the thickness T2 of the substrate layer satisfy the following condition: 0.04 ≤ T1 / T2 ≤ 2.

[0014] In some embodiments, the thickness T3 of the second functional layer and the thickness T2 of the substrate layer satisfy the following condition: 0.04 ≤ T3 / T2 ≤ 2.

[0015] In some implementations, the thickness T3 of the second functional layer and the thickness T1 of the first functional layer satisfy the following condition: 0.2 ≤ T3 / T1 ≤ 8.

[0016] In some implementations, the thickness T1 of the first functional layer satisfies: 0.02mm ≤ T1 ≤ 0.10mm.

[0017] In some embodiments, the thickness T2 of the substrate layer satisfies: 0.05mm ≤ T2 ≤ 0.50mm.

[0018] In some embodiments, the thickness T3 of the second functional layer satisfies: 0.02mm≤T3≤0.10mm.

[0019] In some embodiments, the thickness T of the housing satisfies: 0.1mm ≤ T ≤ 0.6mm.

[0020] In some embodiments, the resistivity of the first functional layer at 20°C is ≤1×10⁻⁶. -7 Ω·m.

[0021] In some embodiments, the resistivity of the second functional layer at 20°C is ≤1×10⁻⁶. -7 Ω·m.

[0022] In some implementations, the thickness T1 of the first functional layer and the thickness T2 of the substrate layer satisfy the condition: 0.1 ≤ T1 / T2 ≤ 1.

[0023] In some embodiments, the thickness T3 of the second functional layer and the thickness T2 of the substrate layer satisfy: 0.1≤T3 / T2≤1.

[0024] In some implementations, the thickness T3 of the second functional layer and the thickness T1 of the first functional layer satisfy the following condition: 0.5 ≤ T3 / T1 ≤ 5.

[0025] In some implementations, the thickness T1 of the first functional layer satisfies: 0.04mm ≤ T1 ≤ 0.06mm.

[0026] In some embodiments, the thickness T2 of the substrate layer satisfies: 0.20mm ≤ T2 ≤ 0.40mm.

[0027] In some embodiments, the thickness T3 of the second functional layer satisfies: 0.04mm ≤ T3 ≤ 0.06mm.

[0028] In some embodiments, the thickness T of the housing satisfies: 0.2mm ≤ T ≤ 0.4mm.

[0029] In some embodiments, the housing further includes a protective layer in the thickness direction, which covers the functional layer, and the protective layer has better corrosion resistance than the functional layer under the same corrosive environment.

[0030] In some embodiments, the corrosion rate s of the protective layer satisfies: s < 1.0 mm / year.

[0031] In some embodiments, the thickness T4 of the protective layer satisfies: 0.0002mm ≤ T4 ≤ 0.50mm.

[0032] In some embodiments, in the height direction of the housing, the housing includes a body portion and a coiled portion, the coiled portion being connected to the body portion and protruding relative to the body portion toward the center of the housing structure. The housing structure also includes a cover plate, the cover plate being connected to the housing.

[0033] In some embodiments, the housing includes a bottom wall and a side wall, the cover plate is disposed at the end of the side wall away from the bottom wall, the rolled portion is bent and connected to the body portion to form a protrusion, in the height direction, there is a first distance D1 between the outer surface of the cover plate and the outer surface of the bottom wall, and there is a second distance D2 between the protrusion and the outer surface of the cover plate, the first distance D1 and the second distance D2 satisfy: D2 / D1≥2%.

[0034] In some embodiments, the cover plate includes a first end cap and a second end cap, which are disposed at opposite ends of the housing. In the height direction, there is a third distance D3 between the outer surfaces of the first end cap and the second end cap, and a fourth distance D4 between the protrusion and the outer surface of the first end cap. The third distance D3 and the fourth distance D4 satisfy: D4 / D3≥2%.

[0035] In some embodiments, the housing further includes a crimping portion connected to the coiling portion and together forming a receiving cavity. The crimping portion includes a first sub-part and a second sub-part, with opposite ends of the first sub-part connected to the coiling portion and the second sub-part, respectively. The housing structure also includes a sealing ring. The sealing ring is at least partially housed within the receiving cavity and located between the cover plate and the housing to seal the gap between the cover plate and the housing.

[0036] In some embodiments, in the housing, all areas corresponding to the body portion, the coiling portion, and the crimping portion include the first functional layer, the base layer, and the second functional layer.

[0037] In some embodiments, in the housing, only the area corresponding to the coiled portion includes the first functional layer, the substrate layer, and the second functional layer.

[0038] In some embodiments, at least a portion of the cover plate extends into the receiving cavity and is wrapped by the sealing ring.

[0039] In some embodiments, a constraint space is formed on the sidewall of the housing or the cover plate, and the sealing ring is housed within the constraint space, including a first and second side that are radially opposed, and a third and fourth side that are axially opposed. The peripheral wall of the constraint space is used to limit and abut against three of the first, second, third, and fourth sides. When the constraint space is formed on the sidewall and the cover plate is connected to the housing, the cover plate limits and abuts against another of the first, second, third, and fourth sides; when the constraint space is formed on the cover plate and the cover plate is connected to the housing, the sidewall limits and abuts against another of the first, second, third, and fourth sides.

[0040] In some embodiments, the cover plate includes a cover plate body and a limiting portion that are in contact with each other. The constraint space includes a groove on the limiting portion, the groove including a bottom wall and a circumferential sidewall that is in contact with the bottom wall, and the sealing ring is accommodated within the groove. The circumferential sidewall is used to limit and abut against the first and second sides of the sealing ring, the bottom wall of the groove is used to limit and abut against one of the third and fourth sides, and the sidewall is used to limit and abut against the other of the third and fourth sides.

[0041] In some embodiments, the constrained space is the receiving cavity, the peripheral wall of the receiving cavity is used to limit and abut against the third side and the fourth side, and the pressing part is used to limit and abut against one of the first side and the second side. The cover plate includes a cover plate body and a limiting part, the limiting part bends and extends from the cover plate body, and is used to limit and abut against the other of the first side and the second side.

[0042] Secondly, this application provides a battery comprising the housing structure and electrode assembly described in any of the above embodiments. The electrode assembly is housed within the housing structure.

[0043] In some embodiments, the electrode assembly is spaced apart from the coiled portion in the height direction of the battery.

[0044] In some embodiments, the battery further includes a busbar electrically connected to the electrode assembly and fixedly connected to the body portion of the housing, wherein the busbar and the coiled portion of the housing are spaced apart and opposite each other in the height direction of the housing.

[0045] Thirdly, this application provides a battery pack. The battery pack includes the battery described in any of the above embodiments.

[0046] Fourthly, this application provides an electrical device. The electrical device includes a battery as described in any of the above embodiments; or a battery pack as described in any of the above embodiments.

[0047] In the battery casing structure, battery, battery pack, and electrical device of this application, the casing structure includes a casing. In the thickness direction, the casing includes a base layer and a functional layer disposed on at least one side of the base layer, and the conductivity of the functional layer is lower than that of the base layer. The functional layer has better corrosion resistance, effectively isolating the electrolyte from direct contact with the base layer and preventing chemical corrosion of the base layer. Simultaneously, the high conductivity of the base layer provides a low-resistance conductive path for the battery's charging and discharging current, reducing the internal resistance of the casing and Joule heat loss, and improving the battery's high-rate overcurrent capability and cycle life.

[0048] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0049] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, wherein: Figure 1 This is a three-dimensional structural schematic diagram of a battery according to some embodiments of this application; Figure 2 yes Figure 1 The diagram shows a cross-sectional view of the battery cut by line II-II; Figure 3 yes Figure 1 The diagram shows a partially enlarged view at point III of the cross-sectional view of the battery taken by line II-II, and the battery of other embodiments of this application. Figure 3 (A) is a partial enlarged view of the same part of the cross-sectional view shown. Figure 4 This application also describes batteries in other embodiments. Figure 2 The cross-sectional diagram shown is a cross-sectional diagram with the same cutting line as the schematic diagram shown. Figure 5 This application also describes batteries in other embodiments. Figure 3 (A) is a partial enlarged view of the same part of the cross-sectional view shown. Figure 6 This application describes batteries in some other embodiments. Figure 3 (A) is a partial enlarged view of the same part of the cross-sectional view shown. Figure 7 This application also describes the battery and... Figure 3(A) is a partial enlarged view of the same part of the cross-sectional view shown. Figure 8 This application also includes some embodiments of the battery and Figure 3 (A) is a partial enlarged view of the same part of the cross-sectional view shown. Figure 9 This application also describes batteries in other embodiments. Figure 3 (A) is a partial enlarged view of the same part of the cross-sectional view shown. Figure 10 This application also describes batteries in other embodiments. Figure 3 (A) is a partial enlarged view of the same part of the cross-sectional view shown. Figure 11 This is a three-dimensional structural schematic diagram of a battery pack according to some embodiments of this application; Figure 12 This is a schematic diagram of the planar structure of an electrical device according to some embodiments of this application.

[0050] The reference numerals in the detailed embodiments are as follows: 10,000 electrical devices; 1,000 battery packs; 100 batteries; 30 electrode assemblies; 50 junction boxes; Shell structure 10; Cover plate 11; Cover plate body 111; Limiting part 113; First bending part 1131; Groove bottom part 1133; Second bending part 1135; First abutting part 1137; Second abutting part 1139; Groove 1130; Groove bottom wall 11301; Circumferential side wall 11303; First surface 114; Second surface 115; Circumferential side surface 116; First end cap 117; Second end cap 118; Shell 13; bottom wall 131; side wall 133; body part 1331; protrusion 1332; crimping part 1333; crimping part 1335; first sub-part 13351; second sub-part 13353; receiving cavity 1337; base layer 1355; functional layer 1357; first functional layer 1358; second functional layer 1359; protective layer 138; Sealing ring 15; First side 1501; Second side 1503; Third side 1505; Fourth side 1507; Altitude direction Z. Detailed Implementation

[0051] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0052] In the description of this application, it should be understood that the terms "center", "length", "upper", "lower", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0053] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0054] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0055] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0056] Battery casings often employ a Ni-Fe-Ni composite structure (i.e., nickel plating on both sides of an iron layer) to balance corrosion resistance and conductivity. However, during manufacturing or long-term use, this composite structure is prone to defects such as localized nickel layer damage, pinholes, or uneven coverage, leading to the exposure of the internal iron layer to the electrolyte or external environment. Once exposed, the exposed iron layer is highly susceptible to chemical and electrochemical corrosion, which can severely result in casing perforation and electrolyte leakage. Simultaneously, iron itself has low conductivity; during high-rate charging and discharging, the iron layer significantly increases the internal resistance of the casing, limiting current flow, causing casing heating, increased energy loss, and even affecting the battery's rate performance and safety. Therefore, the Ni-Fe-Ni composite structure casing suffers from the technical problem of "iron leakage leading to corrosion and insufficient current carrying capacity." To address these issues, this application provides a battery casing structure 10 (… Figure 1 , Figure 2 and Figure 4 As shown), battery 100 ( Figure 1 , Figure 2 and Figure 4 As shown), battery pack 1000 ( Figure 11 (as shown) and electrical equipment 10000 ( Figure 12 (As shown).

[0057] Please refer to Figures 1 to 3 This application provides a housing structure 10 for a battery 100. The housing structure 10 includes a housing 13, which includes a base layer 1355 and a functional layer 1357 disposed on at least one side of the base layer 1355 in the thickness direction. The conductivity of the functional layer 1357 is less than that of the base layer 1355.

[0058] Battery 100 is an electrochemical device that directly converts internally stored chemical energy into direct current electrical energy. The core structure of battery 100 for the electrochemical reaction is the electrode assembly 30 housed within the casing structure 10. The electrode assembly 30 typically consists of one or more independent units capable of undergoing electrochemical reactions, each unit including a positive electrode, a negative electrode, and a separator (not shown). Battery 100 also includes an electrolyte. The electrolyte includes, but is not limited to, lithium salts, organic solvents, and additives. After formation, the electrode assembly 30 has gaps, allowing the electrolyte to enter and wet the electrode assembly 30, ensuring that ions can move freely during charging and discharging. Through a controlled electrochemical reaction, battery 100 establishes a potential difference between the positive and negative electrodes, thereby continuously providing electrical energy to the device being powered when connected to an external circuit. The specific properties of battery 100 and electrode assembly 30 will be described in detail below.

[0059] The casing structure 10 is a structure in the battery 100 used to house structures other than the casing structure 100. The material of the casing structure 10 can be, but is not limited to, steel, aluminum alloy, and polymer materials. Among these, a steel casing structure 10 has excellent compressive strength; an aluminum alloy casing structure 10 has low density, good thermal conductivity, and is easy to process and form; a polymer casing structure 10 has the advantages of good insulation performance and high chemical stability, making it suitable for specific consumer electronics applications. In the figures, this application uses a cylindrical shape for the overall form of the casing structure 10 as an example; however, the overall form of the casing structure 10 can also be a cube or other shapes, and this application does not impose any limitations on this.

[0060] The housing 13 is the main body of the housing structure 10. The size and shape of the housing 13 affect the overall size and shape of the housing structure 10, and directly affect the maximum size that the electrode assembly 30 can be set, thus affecting the energy density of the battery 100. The material of the housing 13 may be, but is not limited to, the steel, aluminum alloy, and polymer materials mentioned above.

[0061] It is understandable that the casing structure 10, as a key component for encapsulating the electrode assembly 30, isolating the external environment, and providing structural support, directly determines the safety and durability of the battery 100 through its structural integrity and reliability. The casing typically employs a Ni-Fe-Ni composite structure, with an iron substrate as the structural support layer and nickel layers deposited on both sides of the iron layer through electroplating or chemical plating. This aims to utilize the high corrosion resistance of the nickel layer and the mechanical strength of the iron substrate to synergistically achieve a balance between electrolyte corrosion resistance and conductive current-carrying capacity. However, the integrity of this composite structure is highly dependent on the plating density and interfacial bonding quality. During stamping, welding heat-affected zones, or long-term cyclic service, the nickel layer is prone to micro-defects such as microcracks, pinholes, or uneven coverage thickness, leading to localized exposure of the iron layer. Exposed iron is highly susceptible to corrosion and cracking, which can penetrate the casing thickness in severe cases, causing electrolyte leakage and insulation failure. Simultaneously, iron has low electrical conductivity; under high-rate charge and discharge conditions, when current is transmitted along the casing axis, the equivalent resistance of the iron layer cross-section will generate a significant ohmic voltage drop. This voltage drop not only limits the peak current throughput, but also causes Joule heat to accumulate inside the iron layer, leading to a localized temperature rise in the casing and further deteriorating the thermal stability of the electrolyte and active materials. To address these issues, this application proposes a corrosion-resistant and highly conductive casing structure 10 to improve the overall performance of the battery 100 using this casing structure 10.

[0062] The substrate layer 1355 is the core structure of the shell 13 and is commonly referred to as the "base material". The material of the substrate layer 1355 can be, but is not limited to, gold, copper, tungsten, aluminum, silver, copper alloys, aluminum alloys, or silver alloys. The substrate layer 1355 determines the overall shape of the shell 13 and at least some of its properties. The functional layer 1357 is a structure within the shell 13 that imparts superior overall performance to the shell 13. For example, the functional layer 1357 can be used to protect the substrate layer 1355 to improve the corrosion resistance of the shell 13, and the functional layer 1357 can structurally strengthen the substrate layer 1355 to enhance the structural strength of the shell 13. The material of the functional layer 1357 can be, but is not limited to, stainless steel, zirconium, titanium, titanium alloys, zinc, copper, copper alloys, and nickel alloys. Depending on the material, the functional layer 1357 can provide different corrosion protection or structural reinforcement functions to the substrate layer 1355.

[0063] In some embodiments, along the thickness direction of the housing 13, the functional layer 1357 is disposed on the inner surface of the base layer 1355 to prevent corrosion of the base layer 1355 due to contact with the electrolyte, and to improve the structural strength and reliability of the housing 13. In other embodiments, the functional layer 1357 is disposed on the outer surface of the base layer 1355 to prevent corrosion of the base layer 1355 due to contact with external corrosive media, and to improve the structural strength and reliability of the housing 13. In still other embodiments, the functional layer 1357 is disposed on both the inner and outer surfaces of the base layer 1355 to prevent corrosion of the base layer 1355 due to contact with both the electrolyte and external corrosive media, and to sufficiently improve the structural strength and reliability of the housing 13. When the conductivity of the functional layer 1357 is less than that of the substrate layer 1355, the substrate layer 1355, which is the main structure of the casing 13, has a higher conductivity, which can significantly reduce the ohmic polarization of the casing 13 and improve the high-current charge and discharge performance of the battery 100. At the same time, it is beneficial to enhance the auxiliary conductivity of the casing 13 as a current collector, providing a low-resistance conductive path for the charge and discharge current of the battery 100. The internal resistance of the casing 13 is low, reducing the risk of local overheating and Joule heat loss, improving the overall efficiency and thermal safety of the battery 100, thereby ensuring that the battery 100 has a long lifespan during cycle use.

[0064] In the casing structure 10 of the battery 100 of this application, the casing structure 10 includes a casing 13. In the thickness direction, the casing 13 includes a base layer 1355 and a functional layer 1357 disposed on at least one side of the base layer 1355, and the conductivity of the functional layer 1357 is lower than that of the base layer 1355. The functional layer 1357 has better corrosion resistance, effectively isolating the electrolyte from direct contact with the base layer 1355 and preventing chemical corrosion of the base layer 1355. At the same time, the high conductivity of the base layer 1355 also provides a low-resistance conductive path for the charging and discharging current of the battery 100, reducing the internal resistance and Joule heat loss of the casing 13, and improving the high-rate overcurrent capability and cycle life of the battery 100.

[0065] Please refer to Figures 1 to 3 In some embodiments, the resistivity of functional layer 1357 at 20°C is ≤1×10⁻⁶. -6 Ω·m.

[0066] The resistivity of functional layer 1357 can be used to reflect the conductivity of functional layer 1357. It is understood that the resistivity of functional layer 1357 affects the internal resistance of battery 100 and the current transmission efficiency during charging and discharging, especially affecting the heat generation and safety performance of battery 100 under high-rate conditions.

[0067] The resistivity of functional layer 1357 at 20°C can be, but is not limited to, 1×10⁻⁶. -7 Ω·m, 0.2×10 -6 Ω·m, 0.3×10 -6 Ω·m, 0.4×10 -6 Ω·m, 0.5×10 -6 Ω·m, 0.6×10 -6 Ω·m, 0.7×10 -6 Ω·m, 0.8×10 -6 Ω·m, 0.9×10 -6 Ω·m and 1×10 -6 Any value of any one of Ω·m, any two of them, or any value within the range of the above values.

[0068] When the resistivity of functional layer 1357 at 20°C meets the above-mentioned range, the resistivity of functional layer 1357 is more suitable, that is, the conductivity of functional layer 1357 is more suitable. At this time, functional layer 1357 helps to reduce the internal resistance of battery 100 without excessively increasing the internal resistance while providing reliable protection. This is beneficial to improving the current transmission efficiency during charging and discharging. Especially under high-rate conditions, it can significantly suppress local heating and maintain a uniform potential distribution, thus significantly improving the overall energy efficiency and safety performance of battery 100.

[0069] Please refer to Figures 1 to 3In some embodiments, the resistivity of the substrate layer 1355 at 20°C is ≤1×10⁻⁶. -7 Ω·m.

[0070] The resistivity of the substrate layer 1355 can be used to reflect the conductivity of the functional layer 1357. It is understood that the resistivity of the substrate layer 1355 affects the internal resistance of the battery 100 and the current transmission efficiency during charging and discharging, especially affecting the heat generation and safety performance of the battery 100 under high-rate operating conditions.

[0071] The resistivity of the 1355 substrate layer at 20°C can be, but is not limited to, 1×10⁻⁶. -8 Ω·m, 0.2×10 -7 Ω·m, 0.3×10 -7 Ω·m, 0.4×10 -7 Ω·m, 0.5×10 -7 Ω·m, 0.6×10 -7 Ω·m, 0.7×10 -7 Ω·m, 0.8×10 -7 Ω·m, 0.9×10 -7 Ω·m and 1×10 -7 Any value of any one of Ω·m, any two of them, or any value within the range of the above values.

[0072] When the resistivity of the substrate layer 1355 at 20°C meets the above-mentioned range, the resistivity of the substrate layer 1355 is suitable, that is, the conductivity of the substrate layer 1355 is suitable. At this time, the 13-ohm polarization of the casing can be significantly reduced, the high-current charge and discharge performance of the battery 100 can be improved, the risk of local overheating and Joule heat loss can be reduced, and the overall efficiency and thermal safety of the battery 100 can be improved, thereby ensuring that the battery 100 has a long lifespan during cycle use.

[0073] Please refer to Figures 1 to 3 In some embodiments, the ratio k of the resistivity of the functional layer 1357 at 20°C to the resistivity of the substrate layer 1355 at 20°C satisfies: 1 <k≤1000。

[0074] As mentioned above, the resistivity of the functional layer 1357 and the resistivity of the substrate layer 1355 will jointly affect the internal resistance of the battery 100 and the current transmission efficiency during charging and discharging, especially affecting the heat generation and safety performance of the battery 100 under high-rate conditions.

[0075] The ratio k of the resistivity of functional layer 1357 at 20°C to the resistivity of substrate layer 1355 at 20°C can be, but is not limited to, any one or any two of 1, 5, 10, 50, 100, 200, 300, 500, 800m and 1000, or any value within the range of the above values.

[0076] When the resistivity of functional layer 1357 at 20°C and the resistivity of substrate layer 1355 at 20°C meet the above-mentioned range, the resistivity of both functional layer 1357 and substrate layer 1355 are suitable, that is, the conductivity of both functional layer 1357 and substrate layer 1355 is suitable. At this time, the casing 13 has low internal resistance and Joule heat loss, thereby ensuring the high-rate overcurrent capability and cycle life of battery 100. Battery 100 has the advantages of good working performance and high safety factor.

[0077] Please refer to Figures 1 to 3 In some embodiments, the functional layer 1357 is at least one of a stainless steel layer, a zirconium layer, a titanium layer, a titanium alloy layer, a zinc layer, a copper layer, a copper alloy layer, and a nickel alloy layer.

[0078] When the functional layer 1357 is a stainless steel layer, the stainless steel layer can effectively block the penetration of external corrosive media with its dense passivation film, while providing high structural hardness and impact toughness, which can effectively resist external mechanical impact and wear, and significantly reduce the risk of plastic deformation of the shell 13 under assembly or vibration conditions.

[0079] When the functional layer 1357 is a zirconium layer, the functional layer 1357 has an extremely low hydrogen diffusion coefficient and good resistance to acid and alkali corrosion. It can form a stable oxide film to prevent corrosion products from penetrating deep into the substrate layer 1355. At the same time, the thermal expansion of zirconium is relatively suitable, which can reduce the tendency of the functional layer 1357 to peel off from the substrate layer 1355 due to interfacial thermal stress caused by temperature cycling, thus ensuring the structural reliability and integrity of the functional layer 1357.

[0080] When the functional layer 1357 is a titanium layer, the functional layer 1357 has passivation self-healing properties. After local coating damage occurs in the functional layer 1357, an oxide film can be quickly generated, which has outstanding self-inhibition ability against pitting corrosion and crevice corrosion.

[0081] When the functional layer 1357 is a titanium alloy layer, the functional layer 1357 exhibits excellent thermal stability and creep resistance under high temperature or high current charging and discharging conditions. It can buffer the interlayer thermal expansion mismatch caused by Joule heating or ambient temperature rise. At the same time, its high resistivity characteristics can help limit the spread of local micro-area arc during abnormal overcurrent, thereby improving safety redundancy.

[0082] When the functional layer 1357 is a zinc layer, the functional layer 1357 can act as a sacrificial anode layer. When there are scratches or pores on the outside of the shell 13, zinc preferentially undergoes anodic dissolution, providing cathodic protection to part of the substrate layer 1355, effectively inhibiting the spread of rust. In addition, zinc has a high hydrogen overpotential, which reduces the risk of hydrogen evolution side reaction and is conducive to maintaining the reliability of the functional layer 1357 in the long term.

[0083] When the functional layer 1357 is a copper layer or a copper alloy layer, it serves as a high electrical and thermal conductivity channel. The excellent current collection and temperature equalization function of the functional layer 1357 can quickly conduct heat from local hot spots in the casing 13 to the outside, preventing heat accumulation that could reduce the bonding strength between the functional layer 1357 and the substrate layer 1355, and also preventing thermal runaway. At the same time, the copper alloy layer also has good wear resistance, which helps to improve the structural strength of the casing 13.

[0084] When the functional layer 1357 is a nickel alloy layer, the functional layer 1357 has both high corrosion resistance and high hardness, and its fine grain structure can improve the peel strength of the bonding interface, so that the functional layer 1357 has the advantages of good corrosion resistance and good structural reliability.

[0085] Therefore, in the casing structure 10 of the battery 100 of this application, at least one of stainless steel layer, zirconium layer, titanium layer, titanium alloy layer, zinc layer, copper layer, copper alloy layer and nickel alloy layer can be flexibly selected as functional layer 1357 according to the application scenario of the battery 100, so as to flexibly meet the multi-dimensional engineering requirements of the casing 13 for corrosion resistance, mechanical strength, conductivity, thermal management and manufacturing cost.

[0086] Please refer to Figures 1 to 3 In some embodiments, functional layer 1357 includes a first functional layer 1358 and a second functional layer 1359. The first functional layer 1358 is disposed on the outer surface of the substrate layer 1355. The second functional layer 1359 is disposed on the inner surface of the substrate layer 1355. The first functional layer 1358 and the second functional layer 1359 are made of the same first material, and the substrate layer 1355 is made of a second material, wherein the conductivity of the first material is less than the conductivity of the second material.

[0087] In the above embodiments, the first functional layer 1358 is a functional layer 1357 disposed on the outer surface of the substrate layer 1355. The first functional layer 1358 may cover the entire outer surface of the substrate layer 1355 to provide stable and reliable anti-corrosion function at all locations of the substrate layer 1355; the first functional layer 1358 may also cover only at least the outer surface of the substrate layer 1355 to provide targeted protection in the areas of the substrate layer 1355 most susceptible to corrosion, and reduce the processing cost required to set the first functional layer 1358, thereby improving the economy of the shell structure 10.

[0088] The second functional layer 1359 is a functional layer 1357 disposed on the inner surface of the substrate layer 1355. The second functional layer 1359 may cover the entire inner surface of the substrate layer 1355 to provide stable and reliable corrosion protection throughout the substrate layer 1355; or the second functional layer 1359 may cover only at least the inner surface of the substrate layer 1355 to provide targeted protection in the areas of the substrate layer 1355 most susceptible to corrosion, and reduce the processing cost required to install the second functional layer 1359, thereby improving the economy of the housing structure 10.

[0089] The first material is the same as that used for the first functional layer 1358 and the second functional layer 1359. Since the materials of the first functional layer 1358 and the second functional layer 1359 are the same, the processing of the shell 13 is simplified, and the processing cost is reduced. The second material is the same as that used for the substrate layer 1355. When the conductivity of the first material is less than that of the second material, the conductivity of the first functional layer 1358 is equal to that of the second functional layer 1359, and the conductivity of the first functional layer 1358 and the second functional layer 1359 is less than that of the substrate layer 1355. The deduction of the beneficial effects is given above and will not be repeated here.

[0090] Therefore, in the casing structure 10 of the battery 100 of this application, a first functional layer 1358 and a second functional layer 1359 are respectively provided on the outer and inner surfaces of the substrate layer 1355, and the corrosion resistance on both sides of the substrate layer 1355 is significantly enhanced. Furthermore, the conductivity of the first functional layer 1358 and the second functional layer 1359 is lower than that of the substrate layer 1355, allowing the substrate layer 1355 to fully utilize its conductivity. This improves the high-rate overcurrent capability and overall efficiency of the battery 100, while also enhancing thermal safety and cycle life.

[0091] Please refer to Figures 1 to 3 In some embodiments, the first functional layer 1358 is at least one of a stainless steel layer, a zirconium layer, a titanium layer, a titanium alloy layer, a zinc layer, a copper layer, a copper alloy layer, and a nickel alloy layer.

[0092] When the first functional layer 1358 is a stainless steel layer, the stainless steel layer can effectively block the penetration of external corrosive media with its dense passivation film, while providing high structural hardness and impact toughness, effectively resisting external mechanical impact and wear, and significantly reducing the risk of plastic deformation of the shell 13 under assembly or vibration conditions.

[0093] When the first functional layer 1358 is a zirconium layer, the first functional layer 1358 has an extremely low hydrogen diffusion coefficient and good resistance to acid and alkali corrosion. It can form a stable oxide film to prevent corrosion products from penetrating deep into the substrate layer 1355. At the same time, the thermal expansion of zirconium is relatively suitable, which can reduce the tendency of the first functional layer 1358 to peel off from the substrate layer 1355 due to interfacial thermal stress caused by temperature cycling, thus ensuring the structural reliability and integrity of the first functional layer 1358.

[0094] When the first functional layer 1358 is a titanium layer, the first functional layer 1358 has passivation self-healing properties. After local coating damage occurs in the first functional layer 1358, an oxide film can be quickly generated, which has outstanding self-inhibition ability against pitting corrosion and crevice corrosion.

[0095] When the first functional layer 1358 is a titanium alloy layer, the first functional layer 1358 exhibits excellent thermal stability and creep resistance under high temperature or high current charging and discharging conditions. It can buffer the interlayer thermal expansion mismatch caused by Joule heating or ambient temperature rise. At the same time, its high resistivity characteristics can help limit the spread of local micro-area arc during abnormal overcurrent, thereby improving safety redundancy.

[0096] When the first functional layer 1358 is a zinc layer, the first functional layer 1358 can serve as a sacrificial anode layer. When there are scratches or pores on the outside of the housing 13, zinc preferentially undergoes anodic dissolution, providing cathodic protection to part of the substrate layer 1355, effectively inhibiting the spread of rust. In addition, zinc has a high hydrogen overpotential, which reduces the risk of hydrogen evolution side reactions and helps to maintain the reliability of the first functional layer 1358 in the long term.

[0097] When the first functional layer 1358 is a copper layer or a copper alloy layer, the first functional layer 1358 serves as a high electrical and thermal conductivity channel. The excellent current collection and temperature equalization effect of the first functional layer 1358 can quickly conduct heat from local hot spots in the shell 13 to the outside, avoiding heat accumulation that could lead to a decrease in the bonding force between the first functional layer 1358 and the substrate layer 1355, and also preventing thermal runaway. At the same time, the copper alloy layer also has good wear resistance, which helps to improve the structural strength of the shell 13.

[0098] When the first functional layer 1358 is a nickel alloy layer, the first functional layer 1358 has both high corrosion resistance and high hardness, and can improve the peel strength of the bonding interface through its fine grain structure, so that the first functional layer 1358 has the advantages of good corrosion resistance and good structural reliability.

[0099] Therefore, in the casing structure 10 of the battery 100 of this application, at least one of stainless steel layer, zirconium layer, titanium layer, titanium alloy layer, zinc layer, copper layer, copper alloy layer and nickel alloy layer can be flexibly selected as the first functional layer 1358 according to the application scenario of the battery 100, so as to flexibly meet the multi-dimensional engineering requirements of the casing 13 for corrosion resistance, mechanical strength, conductivity, thermal management and manufacturing cost.

[0100] Please refer to Figures 1 to 3 In some embodiments, the second functional layer 1359 is at least one of a stainless steel layer, a zirconium layer, a titanium layer, a titanium alloy layer, a zinc layer, a copper layer, a copper alloy layer, and a nickel alloy layer.

[0101] When the second functional layer 1359 is a stainless steel layer, the second functional layer 1359 has excellent corrosion resistance and mechanical strength. In particular, in fluorine-containing electrolytes or high-temperature oxidizing environments, the dense passivation film formed by chromium can effectively inhibit pitting corrosion and intergranular corrosion. At the same time, its high hardness can resist the mechanical stress generated by the expansion of the electrode assembly 30.

[0102] When the second functional layer 1359 is a zirconium layer, the second functional layer 1359 has an extremely low hydrogen permeability coefficient and excellent acid and alkali resistance. It exhibits outstanding resistance to hydrogen embrittlement in acidic or neutral aqueous electrolytes, and its surface natural oxide film has self-healing properties, which can seal micro-defects and block the leakage path of electrolyte to the substrate layer 1355. It is especially suitable for batteries 100 with long cycle life requirements.

[0103] When the second functional layer 1359 is a titanium layer, the passivation film of the second functional layer 1359 remains inert within a wide potential window and is particularly resistant to oxidizing media. At the same time, titanium has a low affinity for active metals such as lithium and sodium, which can reduce side reactions with electrolytes, etc.

[0104] When the second functional layer 1359 is a boron alloy layer, the second functional layer 1359 has an extremely high melting point, good thermal conductivity and low coefficient of thermal expansion, which can maintain the integrity of the interface when the temperature rises sharply, avoid the peeling of the second functional layer 1359 due to thermal mismatch, and the passivation film of the second functional layer 1359 can remain stable in a strongly reducing atmosphere, making it suitable for batteries 100 with demanding high current charge and discharge heat management.

[0105] When the second functional layer 1359 is a zinc layer, it has a sacrificial anode cathodic protection mechanism. When electrolyte invades, the second functional layer 1359 preferentially dissolves, thereby providing electrochemical protection for the substrate layer 1355. In this case, the second functional layer 1359 is suitable for use in batteries 100 with neutral or weakly alkaline systems.

[0106] When the second functional layer 1359 is a copper layer or a copper alloy layer, the second functional layer 1359 exhibits good electrical and thermal conductivity. Copper has extremely low resistivity and excellent weld wettability, which can significantly reduce contact resistance and improve current carrying capacity. Copper alloys, while retaining high conductivity, significantly improve wear resistance and have good metallurgical compatibility with the negative electrode tab material, which helps to reduce the risk of local overheating during negative electrode tab welding.

[0107] When the second functional layer 1359 is a nickel alloy layer, the second functional layer 1359 exhibits excellent resistance to stress corrosion cracking in alkaline electrolyte. At the same time, the oxide layer on the surface of the second functional layer 1359 has a physical barrier effect on organic solvent molecules, which can slow down the chemical corrosion of the substrate layer 1355 by the decomposition products of carbonate solvents. Furthermore, the second functional layer 1359 can maintain dimensional stability for a long time.

[0108] Therefore, in the casing structure 10 of the battery 100 of this application, at least one of stainless steel layer, zirconium layer, titanium layer, titanium alloy layer, zinc layer, copper layer, copper alloy layer and nickel alloy layer can be flexibly selected as the second functional layer 1359 according to the application scenario of the battery 100, so as to flexibly meet the multi-dimensional engineering requirements of the casing 13 for corrosion resistance, mechanical strength, conductivity, thermal management and manufacturing cost.

[0109] Please refer to Figures 1 to 3 In some embodiments, the substrate layer 1355 is at least one of a gold layer, a copper layer, a tungsten layer, an aluminum layer, a silver layer, a copper alloy layer, an aluminum alloy layer, or a silver alloy layer.

[0110] When the substrate layer 1355 is a gold layer, it exhibits excellent chemical inertness and conductivity. The substrate layer 1355 effectively suppresses interfacial side reactions in highly corrosive electrolytes or high-temperature, high-pressure operating environments, maintaining excellent stability even after exposure. Simultaneously, the low contact resistance of the substrate layer 1355 is beneficial for uniform current collection during high-current charging and discharging, making it particularly suitable for specialized fields such as aerospace and medical applications.

[0111] When the substrate layer 1355 is a copper layer, the substrate layer 1355 has excellent electrical and thermal conductivity, which can significantly reduce ohmic polarization and quickly dissipate heat from the inside of the electrode assembly 30, making it suitable for high power density batteries 100.

[0112] When the substrate layer 1355 is a tungsten layer, it has a high melting point, high hardness, and low coefficient of thermal expansion. The substrate layer 1355 can maintain structural stability under extreme temperature cycling and resist deformation caused by internal pressure fluctuations. Furthermore, the density of the substrate layer 1355 can effectively block the permeation of hydrogen or oxygen, thereby improving the sealing reliability of the shell structure 10.

[0113] When the substrate layer 1355 is an aluminum layer, the substrate layer 1355 has the advantages of being lightweight, having high thermal conductivity, being formable, and having a self-passivating oxide film on the surface. This oxide film is insulating and corrosion resistant, and aluminum is abundant and easy to recycle, resulting in a significant cost advantage.

[0114] When the substrate layer 1355 is a silver layer, the substrate layer 1355 has excellent electrical and thermal conductivity, which can minimize the accumulation of Joule heat. At the same time, the substrate layer 1355 has excellent ductility, which makes it easy to achieve thin-wall design and facilitates miniaturization design.

[0115] When the substrate layer 1355 is a copper alloy layer, the substrate layer 1355 retains the excellent electrical and thermal conductivity of copper, and the tensile strength, hardness, wear resistance and stress relaxation resistance are significantly improved by alloying, making it suitable for the casing 13 of the battery 100 that needs to withstand vibration or frequent insertion and removal.

[0116] When the substrate layer 1355 is an aluminum alloy layer, the substrate layer 1355, based on the lightweight and corrosion-resistant properties of pure aluminum, further improves the yield strength and weldability, and has excellent impact resistance. At the same time, the substrate layer 1355 maintains good extrudability, which is convenient for manufacturing shells 13 with complex cross-sectional structures, and the oxide layer on the surface helps to improve hardness and insulation.

[0117] When the substrate layer 1355 is a silver alloy layer, the substrate layer 1355 combines the high electrical and thermal conductivity of silver with the corrosion resistance and arc erosion resistance of the alloy, making it particularly suitable for high voltage or high frequency pulse conditions and exhibiting good overall performance.

[0118] Therefore, in the casing structure 10 of the battery 100 of this application, at least one of the following can be flexibly selected as the base layer 1355: gold layer, copper layer, tungsten layer, aluminum layer, silver layer, copper alloy layer, aluminum alloy layer or silver alloy layer, depending on the application scenario of the battery 100. This allows for flexible material selection and structural design based on the operating temperature, power density, life requirements and economy of the battery 100, thereby fully improving the practicality of the battery 100.

[0119] Please refer to Figures 1 to 3 In some implementations, the thickness T1 of the first functional layer 1358 satisfies: 0.02mm≤T1≤0.10mm.

[0120] Please refer to Figure 3 (B) Figure 3(B) shows the thickness T1 of the first functional layer 1358. The thickness T1 of the first functional layer 1358 is related to the protective effect of the first functional layer 1358 on the substrate layer 1355, and affects the corrosion resistance, reliability, and economy of the housing 13. The thickness T1 of the first functional layer 1358 can be, but is not limited to, any one or any two of 0.02 mm, 0.03 mm, 0.04 mm, 0.05 mm, 0.06 mm, 0.065 mm, 0.07 mm, 0.08 mm, 0.09 mm, and 0.10 mm.

[0121] When the thickness T1 of the first functional layer 1358 meets the above-mentioned range, the thickness T1 of the first functional layer 1358 is more suitable. The molding process of the first functional layer 1358 is simple and the yield rate is high. The first functional layer 1358 can provide good protection for the substrate layer 1355, fully improve the corrosion resistance of the shell 13, and can also strengthen the structure of the substrate layer 1355. At the same time, the space size and weight occupied by the first functional layer 1358 are more suitable, the overall size and weight of the battery 100 are smaller, the battery 100 has better portability and lower processing cost.

[0122] Please refer to Figures 1 to 3 In some implementations, the thickness T1 of the first functional layer 1358 satisfies: 0.04mm≤T1≤0.06mm.

[0123] As mentioned above, the thickness T1 of the first functional layer 1358 is related to the protective effect of the first functional layer 1358 on the substrate layer 1355, and affects the corrosion resistance, reliability, and economy of the shell 13. The thickness T1 of the first functional layer 1358 can be, but is not limited to, any one or any two of the following: 0.04mm, 0.042mm, 0.044mm, 0.046mm, 0.048mm, 0.05mm, 0.052mm, 0.054mm, 0.056mm, and 0.06mm.

[0124] When the thickness T1 of the first functional layer 1358 meets the above-mentioned range, the thickness T1 of the first functional layer 1358 is further optimized. At this time, the first functional layer 1358 has a good protective effect on the substrate layer 1355, greatly improving the corrosion resistance of the shell 13. Moreover, the first functional layer 1358 has excellent structural reinforcement effect on the substrate layer 1355. At the same time, the space size and mass occupied by the first functional layer 1358 are optimized, and the battery 100 has a suitable overall size and weight, effectively ensuring the portability and economy of the battery 100.

[0125] Please refer to Figures 1 to 3In some embodiments, the thickness T2 of the substrate layer 1355 satisfies: 0.05mm≤T2≤0.50mm.

[0126] Please refer to Figure 3 , Figure 3 (A) and Figure 3 (B) shows the thickness T2 of the first functional layer 1358. The thickness T2 of the substrate layer 1355 is related to the structural stability and reliability of the substrate layer 1355, and affects the structural strength, reliability, and economy of the shell 13. The thickness T2 of the substrate layer 1355 can be, but is not limited to, any one or any two of 0.05 mm, 0.10 mm, 0.15 mm, 0.20 mm, 0.25 mm, 0.30 mm, 0.35 mm, 0.40 mm, 0.45 mm, and 0.50 mm.

[0127] When the thickness T2 of the substrate layer 1355 meets the above range, the thickness T2 of the substrate layer 1355 is more suitable. The molding process of the substrate layer 1355 is simple and the yield rate is high. The substrate layer 1355 has good structural stability and structural strength, and is not easy to deform or break. At the same time, it will not occupy a large space size and weight due to excessive thickness. In this case, the battery 100 can have a small overall size and weight, thereby optimizing the portability and processing cost of the battery 100.

[0128] Please refer to Figures 1 to 3 In some embodiments, the thickness T2 of the substrate layer 1355 satisfies: 0.20mm≤T2≤0.40mm.

[0129] As mentioned above, the thickness T2 of the substrate layer 1355 is related to the structural stability and reliability of the substrate layer 1355, and affects the structural strength, reliability, and economy of the shell 13. The thickness T2 of the substrate layer 1355 can be, but is not limited to, any one or any two of the following values: 0.20 mm, 0.22 mm, 0.24 mm, 0.26 mm, 0.28 mm, 0.30 mm, 0.32 mm, 0.35 mm, 0.37 mm, and 0.40 mm.

[0130] When the thickness T2 of the substrate layer 1355 meets the above range, the thickness T2 of the substrate layer 1355 is further optimized, which significantly improves the molding difficulty and yield of the substrate layer 1355. At this time, the structural stability and structural strength of the substrate layer 1355 are excellent, and it has suitable spatial size and mass. Therefore, the battery 100 has good portability and suitable processing cost, which significantly improves the practicality of the battery 100.

[0131] Please refer to Figures 1 to 3In some embodiments, the thickness T3 of the second functional layer 1359 satisfies: 0.02mm≤T3≤0.10mm.

[0132] Please refer to Figure 3 (B) Figure 3 (B) shows the thickness T3 of the second functional layer 1359. The thickness T3 of the second functional layer 1359 is related to the protective effect of the second functional layer 1359 on the substrate layer 1355, and affects the corrosion resistance, reliability, and economy of the housing 13. The thickness T3 of the second functional layer 1359 can be, but is not limited to, any one or any two of 0.02 mm, 0.03 mm, 0.04 mm, 0.05 mm, 0.06 mm, 0.065 mm, 0.07 mm, 0.08 mm, 0.09 mm, and 0.10 mm.

[0133] When the thickness T3 of the second functional layer 1359 meets the above-mentioned range, the thickness T3 of the second functional layer 1359 is more suitable. The molding process of the second functional layer 1359 is simple and the yield rate is high. The second functional layer 1359 can provide good protection for the substrate layer 1355, fully improve the corrosion resistance of the shell 13, and can also strengthen the structure of the substrate layer 1355. At the same time, the space size and weight occupied by the second functional layer 1359 are more suitable, the overall size and weight of the battery 100 are smaller, the battery 100 has better portability and lower processing cost.

[0134] Please refer to Figures 1 to 3 In some embodiments, the thickness T3 of the second functional layer 1359 satisfies: 0.04mm≤T3≤0.06mm.

[0135] As mentioned above, the thickness T3 of the second functional layer 1359 is related to the protective effect of the second functional layer 1359 on the substrate layer 1355, and affects the corrosion resistance, reliability, and economy of the shell 13. The thickness T3 of the second functional layer 1359 can be, but is not limited to, any one or any two of the following values: 0.04 mm, 0.042 mm, 0.044 mm, 0.046 mm, 0.048 mm, 0.05 mm, 0.052 mm, 0.054 mm, 0.056 mm, and 0.06 mm.

[0136] When the thickness T3 of the second functional layer 1359 meets the above-mentioned range, the thickness T3 of the second functional layer 1359 is further optimized. At this time, the second functional layer 1359 has a good protective effect on the substrate layer 1355, greatly improving the corrosion resistance of the shell 13. Moreover, the second functional layer 1359 has an excellent effect on the structural reinforcement of the substrate layer 1355. At the same time, the space size and mass occupied by the second functional layer 1359 are optimized, and the battery 100 has a suitable overall size and weight, effectively ensuring the portability and economy of the battery 100.

[0137] Please refer to Figures 1 to 3 In some embodiments, the thickness T1 of the first functional layer 1358 and the thickness T2 of the substrate layer 1355 satisfy: 0.04≤T1 / T2≤2.

[0138] As mentioned above, the thickness T1 of the first functional layer 1358 is related to the protective effect of the first functional layer 1358 on the substrate layer 1355, and affects the corrosion resistance, reliability, and economy of the shell 13. The thickness T2 of the substrate layer 1355 is related to the structural stability and reliability of the substrate layer 1355, and affects the structural strength, reliability, and economy of the shell 13. The ratio of the thickness T1 of the first functional layer 1358 to the thickness T2 of the substrate layer 1355 can be, but is not limited to, any one or any two of 0.04, 0.05, 0.1, 0.2, 0.25, 0.5, 1, 1.2, 1.5, and 2.

[0139] When the ratio of the thickness T1 of the first functional layer 1358 to the thickness T2 of the substrate layer 1355 meets the above-mentioned range, both the thickness T1 of the first functional layer 1358 and the thickness T2 of the substrate layer 1355 are suitable. At this time, the protective effect of the first functional layer 1358 on the substrate layer 1355 and the structural reinforcement effect are ensured, as well as the structural strength and reliability of the substrate layer 1355. At the same time, the first functional layer 1358 and the substrate layer 1355 also have the advantages of easy processing, high yield, and superior size and weight. The battery 100 has the advantages of good reliability, good portability, good economy and long service life.

[0140] Please refer to Figures 1 to 3 In some embodiments, the thickness T1 of the first functional layer 1358 and the thickness T2 of the substrate layer 1355 satisfy: 0.1≤T1 / T2≤1.

[0141] As mentioned above, the thickness T1 of the first functional layer 1358 is related to the protective effect of the first functional layer 1358 on the substrate layer 1355, and affects the corrosion resistance, reliability, and economy of the shell 13. The thickness T2 of the substrate layer 1355 is related to the structural stability and reliability of the substrate layer 1355, and affects the structural strength, reliability, and economy of the shell 13. The ratio of the thickness T1 of the first functional layer 1358 to the thickness T2 of the substrate layer 1355 can be, but is not limited to, any one or any two of 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, and 1.

[0142] When the ratio of the thickness T1 of the first functional layer 1358 to the thickness T2 of the substrate layer 1355 meets the above-mentioned range, the thickness T1 of the first functional layer 1358 and the thickness T2 of the substrate layer 1355 are further optimized. At this time, the protective effect of the first functional layer 1358 on the substrate layer 1355 and the structural reinforcement effect are fully guaranteed. The structural strength and reliability of the substrate layer 1355 are greatly optimized, and the processability, yield and lightweight of the first functional layer 1358 and the substrate layer 1355 are significantly improved. This greatly improves the reliability, portability, economy and service life of the battery 100.

[0143] Please refer to Figures 1 to 3 In some embodiments, the thickness T3 of the second functional layer 1359 and the thickness T2 of the substrate layer 1355 satisfy: 0.04≤T3 / T2≤2.

[0144] As mentioned above, the thickness T3 of the second functional layer 1359 is related to the protective effect of the second functional layer 1359 on the substrate layer 1355, and affects the corrosion resistance, reliability, and economy of the shell 13. The thickness T2 of the substrate layer 1355 is related to the structural stability and reliability of the substrate layer 1355, and affects the structural strength, reliability, and economy of the shell 13. The ratio of the thickness T3 of the second functional layer 1359 to the thickness T2 of the substrate layer 1355 can be, but is not limited to, any one or any two of 0.04, 0.05, 0.1, 0.2, 0.25, 0.5, 1, 1.2, 1.5, and 2.

[0145] When the ratio of the thickness T3 of the second functional layer 1359 to the thickness T2 of the substrate layer 1355 meets the above-mentioned range, both the thickness T3 of the second functional layer 1359 and the thickness T2 of the substrate layer 1355 are suitable. At this time, the protective effect of the second functional layer 1359 on the substrate layer 1355 and the structural reinforcement effect are ensured, as well as the structural strength and reliability of the substrate layer 1355. At the same time, the second functional layer 1359 and the substrate layer 1355 also have the advantages of easy processing, high yield, and superior size and weight. The battery 100 has the advantages of good reliability, good portability, good economy and long service life.

[0146] Please refer to Figures 1 to 3 In some embodiments, the thickness T3 of the second functional layer 1359 and the thickness T2 of the substrate layer 1355 satisfy: 0.1≤T3 / T2≤1.

[0147] As mentioned above, the thickness T3 of the second functional layer 1359 is related to the protective effect of the second functional layer 1359 on the substrate layer 1355, and affects the corrosion resistance, reliability, and economy of the shell 13. The thickness T2 of the substrate layer 1355 is related to the structural stability and reliability of the substrate layer 1355, and affects the structural strength, reliability, and economy of the shell 13. The ratio of the thickness T3 of the second functional layer 1359 to the thickness T2 of the substrate layer 1355 can be, but is not limited to, any one or any two of 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, and 1.

[0148] When the ratio of the thickness T3 of the second functional layer 1359 to the thickness T2 of the substrate layer 1355 meets the above-mentioned range, the thickness T3 of the second functional layer 1359 and the thickness T2 of the substrate layer 1355 are further optimized. At this time, the protective effect of the second functional layer 1359 on the substrate layer 1355 and the structural reinforcement effect are fully guaranteed. The structural strength and reliability of the substrate layer 1355 are greatly optimized, and the processability, yield and lightweight of the second functional layer 1359 and the substrate layer 1355 are significantly improved. This greatly improves the reliability, portability, economy and service life of the battery 100.

[0149] Please refer to Figures 1 to 3 In some embodiments, the thickness T3 of the second functional layer 1359 and the thickness T1 of the first functional layer 1358 satisfy: 0.2≤T3 / T1≤8.

[0150] As mentioned above, the thickness T1 of the first functional layer 1358 is related to the protective effect of the first functional layer 1358 on the substrate layer 1355, and the thickness T3 of the second functional layer 1359 is related to the protective effect of the first functional layer 1358 on the substrate layer 1355. Together, they affect the corrosion resistance, reliability, and economy of the shell 13. The ratio of the thickness T3 of the second functional layer 1359 to the thickness T1 of the first functional layer 1358 can be, but is not limited to, any one or any two of 0.2, 0.5, 0.8, 1, 1.5, 2, 3, 4, 5, and 8.

[0151] When the ratio of the thickness T3 of the second functional layer 1359 to the thickness T1 of the first functional layer 1358 meets the above-mentioned range, both the thickness T3 of the second functional layer 1359 and the thickness T1 of the first functional layer 1358 are suitable. At this time, the protective effect of the first functional layer 1358 and the second functional layer 1359 on the substrate layer 1355 and the structural reinforcement effect are ensured, and the corrosion resistance and reliability of the substrate layer 1355 are ensured. At the same time, the first functional layer 1358 and the second functional layer 1359 also have the advantages of easy processing, high yield, and superior size and weight. The battery 100 has the advantages of good reliability, good portability, good economy and long service life.

[0152] Please refer to Figures 1 to 3 In some embodiments, the thickness T3 of the second functional layer 1359 and the thickness T1 of the first functional layer 1358 satisfy: 0.5≤T3 / T1≤5.

[0153] As mentioned above, the thickness T1 of the first functional layer 1358 is related to the protective effect of the first functional layer 1358 on the substrate layer 1355, and the thickness T3 of the second functional layer 1359 is related to the protective effect of the first functional layer 1358 on the substrate layer 1355. Together, they affect the corrosion resistance, reliability, and economy of the shell 13. The ratio of the thickness T3 of the second functional layer 1359 to the thickness T1 of the first functional layer 1358 can be, but is not limited to, any one or any two of 0.5, 0.8, 1, 1.5, 2, 2.5, 3, 4, 4.5, and 5.

[0154] When the ratio of the thickness T3 of the second functional layer 1359 to the thickness T1 of the first functional layer 1358 meets the above-mentioned range, the thickness T3 of the second functional layer 1359 and the thickness T1 of the first functional layer 1358 are further optimized. At this time, the protective effect of the first functional layer 1358 and the second functional layer 1359 on the substrate layer 1355 and the structural reinforcement effect are significantly improved, greatly optimizing the corrosion resistance and reliability of the substrate layer 1355. At the same time, the processability, yield and lightweighting of the first functional layer 1358 and the second functional layer 1359 greatly improve the reliability, portability, economy and service life of the battery 100.

[0155] Please refer to Figures 1 to 3 In some embodiments, the thickness T of the housing 13 satisfies: 0.1mm≤T≤0.6mm.

[0156] It is understood that the shell 13 is mainly used to provide structural support for the shell structure 10. The thickness T of the shell 13 directly affects the structural strength, economic performance, and energy density of the battery 100. The thickness T of the shell 13 can be, but is not limited to, any one or any two of the following: 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, and 0.6 mm.

[0157] When the thickness T of the casing 13 meets the above-mentioned range, the thickness T of the casing 13 is relatively suitable, the structural strength of the casing 13 is relatively high, the casing 13 is not easily damaged during the production process, the yield rate of the casing structure 10 is relatively high, and the casing 13 also has great structural strength in subsequent use, resulting in good structural reliability and service life of the battery 100. In addition, among casing structures 10 of the same volume, the casing 13 does not excessively compress the internal space of the casing structure 10, the maximum size of the electrode assembly 30 can be set to be relatively large, the energy density of the battery 100 is relatively high, and the portability and practicality of the battery 100 are both good.

[0158] Please refer to Figures 1 to 3 In some embodiments, the thickness T of the housing 13 satisfies: 0.2mm≤T≤0.4mm.

[0159] As mentioned above, the thickness T of the housing 13 determines the structural strength, economic performance, and energy density of the housing structure 10 and the battery 100. In some embodiments, the thickness T of the housing 13 may be, but is not limited to, any one or any two of the following: 0.2 mm, 0.22 mm, 0.24 mm, 0.26 mm, 0.28 mm, 0.3 mm, 0.32 mm, 0.34 mm, 0.36 mm, 0.38 mm, and 0.4 mm.

[0160] With the thickness T of the housing 13 meeting the above-mentioned range, the thickness T of the housing 13 is further optimized. This ensures that the housing 13 has high structural strength and good structural stability, and that the yield rate of the housing structure 10 is high, so that the battery 100 has excellent structural reliability and a long service life. In addition, the housing 13 provides ample layout space for the electrode assembly 30, greatly optimizing the energy density of the battery 100 and ensuring that the battery 100 is both portable and practical.

[0161] Please refer to Figures 1 to 3 In some embodiments, the resistivity of the first functional layer 1358 at 20°C is ≤1×10⁻⁶. -7 Ω·m.

[0162] In the above embodiments, the first functional layer 1358 can be made of a metal material with high conductivity to work in conjunction with the substrate layer 1355 to ensure excellent current collection and heat conduction performance and reduce ohmic losses. The resistivity of the first functional layer 1358 is used to reflect the conductivity of the first functional layer 1358, thereby affecting the internal resistance of the battery 100 and the current transmission efficiency during charging and discharging, especially affecting the heat generation and safety performance of the battery 100 under high-rate operating conditions.

[0163] The resistivity of the first functional layer 1358 at 20°C can be, but is not limited to, 1×10⁻⁶. -8 Ω·m, 0.2×10 -7 Ω·m, 0.3×10 -7 Ω·m, 0.4×10 -7 Ω·m, 0.5×10 -7 Ω·m, 0.6×10 -7 Ω·m, 0.7×10 -7 Ω·m, 0.8×10 -7 Ω·m, 0.9×10 -7 Ω·m and 1×10 -7 Any value between any one or any two of the values ​​in Ω·m, or any value within the range mentioned above. When the resistivity of the first functional layer 1358 at 20°C meets the above range, the resistivity of the first functional layer 1358 is relatively small, the conductivity of the first functional layer 1358 is relatively large, and the conductivity of the substrate layer 1355 is also relatively large. In this case, the first functional layer 1358 helps to reduce the contact resistance between the substrate layer 1355 and the electrode or busbar 50, thereby reducing ohmic polarization and improving the current transmission efficiency during charging and discharging. Especially under high-rate conditions, it can significantly suppress local heating and maintain a uniform potential distribution, significantly improving the overall energy efficiency and safety performance of the battery 100.

[0164] Please refer to Figures 1 to 3In some embodiments, the resistivity of the second functional layer 1359 at 20°C is ≤1×10⁻⁶. -7 Ω·m.

[0165] In the above embodiments, the second functional layer 1359 can be made of a metal material with high conductivity to work in conjunction with the substrate layer 1355 to ensure excellent current collection and heat conduction performance and reduce ohmic losses. The resistivity of the second functional layer 1359 reflects its conductivity, thereby affecting the internal resistance of the battery 100 and the current transmission efficiency during charging and discharging, especially affecting the heat generation and safety performance of the battery 100 under high-rate operating conditions.

[0166] The resistivity of the second functional layer 1359 at 20°C can be, but is not limited to, 1×10⁻⁶. -8 Ω·m, 0.2×10 -7 Ω·m, 0.3×10 -7 Ω·m, 0.4×10 -7 Ω·m, 0.5×10 -7 Ω·m, 0.6×10 -7 Ω·m, 0.7×10 -7 Ω·m, 0.8×10 -7 Ω·m, 0.9×10 -7 Ω·m and 1×10 -7 Any value of any one of Ω·m, any two of them, or any value within the range of the above values.

[0167] When the resistivity of the second functional layer 1359 at 20°C meets the above-mentioned range, the resistivity of the second functional layer 1359 is relatively small, the conductivity of the second functional layer 1359 is relatively large, and the conductivity of the substrate layer 1355 is also relatively large. At this time, the second functional layer 1359 helps to reduce the contact resistance between the substrate layer 1355 and the electrode or busbar 50, thereby reducing ohmic polarization and improving the current transmission efficiency during charging and discharging. Especially under high-rate conditions, it can significantly suppress local heating and maintain a uniform potential distribution, significantly improving the overall energy efficiency and safety performance of the battery 100.

[0168] Please refer to Figures 1 to 3 In some embodiments, the housing 13 further includes a protective layer 138 in the thickness direction, which covers the functional layer 1357. Under the same corrosive environment, the corrosion resistance of the protective layer 138 is better than that of the functional layer 1357.

[0169] The protective layer 138 is at least a partial structure in the housing 13 for protecting the functional layer 1357. In the thickness direction, the protective layer 138 is stacked with and covers the functional layer 1357. It can be understood that when the functional layer 1357 is disposed on the inner surface of the substrate layer 1355, the protective layer 138 is disposed on the inner surface of the functional layer 1357; when the functional layer 1357 is disposed on the outer surface of the substrate layer 1355, the protective layer 138 is disposed on the outer surface of the functional layer 1357.

[0170] Under the same corrosive environment, such as corrosion caused by the electrolyte inside the housing structure 10, or corrosion caused by corrosive media in the external environment of the housing structure 10, the protective layer 138 has better corrosion resistance than the functional layer 1357. Therefore, the protective layer 138 can prevent the functional layer 1357 from corroding, effectively preventing the functional layer 1357 from being corroded, and significantly improving the corrosion resistance and service life of the housing 13. In some embodiments, the protective layer 138 is a nickel layer and covers the inner surface of the second functional layer 1359; in other embodiments, the protective layer 138 is a blue film and covers the outer surface of the first functional layer 1358.

[0171] Therefore, in the casing structure 10 of the battery 100 of this application, under the same corrosive environment, the corrosion resistance of the protective layer 138 is better than that of the functional layer 1357. At this time, the protective layer 138 can provide protection for the functional layer 1357. The multi-layer structure greatly improves the overall corrosion resistance of the casing 13, greatly avoids corrosion damage to the casing 13, and fully improves the reliability and service life of the battery 100.

[0172] In some embodiments, at least one of the first functional layer 1358, the second functional layer 1359, and the protective layer 138 is continuously distributed on the substrate layer 1355 or the functional layer 1357, forming a continuous ring. In this case, the first functional layer 1358 and / or the second functional layer 1359 can adequately protect the substrate layer 1355 in the circumferential direction. The protective layer 138 can adequately protect the functional layer 1357 in the circumferential direction.

[0173] In other embodiments, at least one of the first functional layer 1358, the second functional layer 1359, and the protective layer 138 is distributed circumferentially around the substrate layer 1355 or the functional layer 1357, forming an intermittent ring. In this case, the range of the first functional layer 1358, the second functional layer 1359, and the protective layer 138 is smaller, and the processing cost of the first functional layer 1358, the second functional layer 1359, and the protective layer 138 is lower. This is suitable for the casing structure 10 of the battery 100 where corrosion resistance requirements are not high but production costs are more sensitive.

[0174] Please refer to Figures 1 to 3 In some embodiments, the corrosion rate s of the protective layer 138 satisfies: s < 1.0 mm / year.

[0175] In the above embodiments, ISO 9223:2012 establishes a framework for classifying the corrosivity levels of metallic materials based on the deposition rates of sulfur dioxide and chloride ions in the ambient atmosphere, and provides a reference range for the annual corrosion rate of standard metals under specific exposure conditions. This corrosion rate is typically expressed as thickness reduction (mm / year), and its determination must be based on the environmental parameter measurement methods specified in ISO 9225:2021 and the standard specimen exposure test methods specified in ISO 9226:2012.

[0176] The corrosion rate s of the protective layer 138 represents the corrosion resistance of the protective layer 138, thereby affecting the protective effect on the functional layer 1357. The corrosion rate s of the protective layer 138 may be, but is not limited to, any one, any two of the following values: 0.4 mm / year, 0.5 mm / year, 0.65 mm / year, 0.6 mm / year, 0.75 mm / year, 0.7 mm / year, 0.85 mm / year, 0.8 mm / year, 0.95 mm / year, and 0.9 mm / year, or any value within the range of the above values.

[0177] When the corrosion rate s of the protective layer 138 meets the above-mentioned range, the corrosion rate s of the protective layer 138 is small, the corrosion resistance of the protective layer 138 is good, and the protective layer 138 provides good protection for the functional layer 1357. Thus, it can work together with the functional layer 1357 to improve the corrosion resistance of the shell 13, ensure the long-term reliability of the shell structure 10, and greatly optimize the safety and service life of the battery 100.

[0178] Please refer to Figures 1 to 3 In some embodiments, the thickness T4 of the protective layer 138 satisfies: 0.0002mm≤T4≤0.50mm.

[0179] Please refer to Figure 3 (B) Figure 3(B) shows the thickness T4 of the protective layer 138. The thickness T4 of the protective layer 138 is related to the protective effect of the protective layer 138 on the functional layer 1357, and affects the corrosion resistance, reliability, and economy of the housing 13. The thickness T4 of the protective layer 138 can be, but is not limited to, any one or any two of the following: 0.0002 mm, 0.0005 mm, 0.001 mm, 0.002 mm, 0.005 mm, 0.01 mm, 0.05 mm, 0.1 mm, 0.25 mm, and 0.5 mm.

[0180] When the thickness T4 of the protective layer 138 meets the above range, the thickness T4 of the protective layer 138 is more suitable. The molding process of the protective layer 138 is simple and the yield rate is high. Moreover, the protective layer 138 can provide good protection for the functional layer 1357, thereby fully improving the overall corrosion resistance of the casing 13. At the same time, the space size and weight occupied by the first functional layer 1358 are more suitable, and the overall size and weight of the battery 100 will not increase significantly, which is conducive to ensuring the portability and economy of the battery 100.

[0181] Please refer to Figures 1 to 4 In some embodiments, in the height direction z of the housing 13, the housing 13 includes a body portion 1331 and a coiled portion 1333, the coiled portion 1333 being connected to the body portion 1331 and protruding relative to the body portion 1331 toward the center of the housing structure 10. The housing structure 10 also includes a cover plate 11, which is connected to the housing 13.

[0182] The main body 1331 is the main structure of the shell 13. The coiled portion 1333 is a structure formed by the deformation of the shell 13 under a predetermined processing technology. The coiled portion 1333 is connected to the end of the main body 1331 away from the end of the shell 13 where the coiled portion 1333 is not located, and protrudes relative to the main body 1331 towards the center of the shell structure 10, such as... Figure 2 and Figure 3 As shown. It can be understood that the function of the coiling part 1333 includes, but is not limited to: fixing the electrode assembly 30 by restricting the position of the electrode assembly 30 in the height direction Z of the housing 13, fixing the busbar structure (the busbar plate 50 described below) by restricting the position of the busbar structure in the height direction Z, and sealing the housing structure 10.

[0183] Cover plate 11 is a structure in shell structure 10 used to cover shell 13. Shell 13 and cover plate 11 can be directly connected or indirectly connected. When shell 13 and cover plate 11 are directly connected, the connection method is usually non-removable. Non-removable connection includes, but is not limited to, one or more combinations of methods such as gluing, welding, and sintering. This definition will be used for subsequent non-removable connections and will not be elaborated further.

[0184] The housing 13 and the cover plate 11 together form a spatial structure for accommodating the electrode assembly 30 and other structures. It is understood that the dimensions and shape of the internal spatial structure of the housing structure 10 are jointly determined by the dimensions and shape of the housing 13, the dimensions and shape of the cover plate 11, and the connection method between the housing 13 and the cover plate 11, and directly affect the maximum size that the electrode assembly 30 can be set, thereby affecting the energy density of the battery 100. For example, the housing 13 and the cover plate 11 are sealed by a grooving process or by a welding process to ensure the sealing and safety of the battery 100.

[0185] It should be noted that when the shell structure 10 includes a shell 13 and a cover plate 11, the shell structure 10 may not be made of a single material. For example, the shell 13 and the cover plate 11 may be made of the same material, either steel or aluminum alloy. The shell structure 10 may also have different components made of different materials. For example, the shell 13 may be made of steel, while the cover plate 11 may be made of aluminum alloy. Of course, the materials of the shell 13 and the cover plate 11 can also be combined in other ways, which will not be listed here.

[0186] Therefore, in the housing structure 10 of this application, the housing 13 includes a body part 1331 and a coiling part 1333 connected to each other. The coiling part 1333 protrudes toward the center of the housing structure 10 relative to the body part 1331 to provide a position reference for the installation of the cover plate 11, which is beneficial to improving the reliability of the connection between the housing 13 and the cover plate 11. At this time, the structural reliability and structural stability of the housing structure 10 are better.

[0187] Please refer to Figures 1 to 3 In some embodiments, the housing 13 includes a bottom wall 131 and a side wall 133. A cover plate 11 is disposed at the end of the side wall 133 away from the bottom wall 131. A rolled portion 1333 is bent and connected to the body portion 1331 to form a protrusion 1332. In the height direction Z, there is a first distance D1 between the outer surface of the cover plate 11 and the outer surface of the bottom wall 131, and a second distance D1 between the protrusion 1332 and the outer surface of the cover plate 11. The first distance D1 and the second distance D2 satisfy: D2 / D1≥2%.

[0188] The bottom wall 131 is at least a partial structure of the bottom of the housing 13. After the housing structure 10 is assembled, the bottom wall 131 and the cover plate 11 are opposite each other in the height direction Z of the housing structure 10. The side wall 133 is at least a partial structure of the side of the housing 13. The side wall 133 is connected to the periphery of the bottom wall 131 and extends from the periphery of the bottom wall 131. The side wall 133 and the bottom wall 131 can be an integral structure or a separate structure. When the side wall 133 and the bottom wall 131 are separate structures, the connection between the side wall 133 and the bottom wall 131 is usually a non-removable connection. It is understood that the side wall 133 is also used to connect with the cover plate 11 to enclose the electrode assembly 30 in the housing structure 10. It is understood that the body portion 1331, the crimping portion 1333, and the crimping portion 1335, which will be described below, are all at least a partial structure of the side wall 133.

[0189] It should be noted that the division of the shell 13 here into at least a bottom wall 131 and a side wall 133, and the above-described division of the shell 13 into at least a base layer 1355 and a functional layer 1357, are descriptions of the shell 13 from different perspectives and do not conflict with each other. It can be understood, exemplarily, that the side wall 133 may include a portion of the base layer 1355 corresponding to the side wall 133 and a functional layer 1357 disposed inside and / or outside that portion of the base layer 1355.

[0190] The protrusion 1332 is at least a partial structure that protrudes outward toward the exterior of the shell 13, formed by the bending and joining of the rolled portion 1333 and the main body portion 1331. Please refer to... Figure 2 and Figure 4 It can be understood that the protrusion 1332 includes at least a portion of the structure of the coiled portion 1333 and at least a portion of the structure of the body portion 1331, and the space between the protrusion 1332 and the end of the housing 13 furthest from the protrusion 1332 is used to install the electrode assembly 30.

[0191] This application defines the distance in the height direction Z between the outer surface of the cover plate 11 and the outer surface of the bottom wall 131 as the first distance D1, and the distance in the height direction Z between the protrusion 1332 and the outer surface of the cover plate 11 as the second distance D2. Figure 2 As shown. It should be noted that, in the process of measuring the second distance D2, the point where the protrusion 1332 is farthest from the bottom wall 131 of the shell structure 10 is taken as the reference point, and the vertical distance between this point and the outer surface of the cover plate 11 in the height direction Z is measured as the second distance D2.

[0192] It can be understood that the first distance D1 is used to represent the overall dimensions of the housing structure 10, i.e., the battery 100, while the second distance D2 is used to represent the dimensions and overall shape of at least a portion of the structure of the housing 13 used to combine with the cover plate 11 (at least a portion of the rolled portion 1333) in the height direction Z. The ratio of the first distance D1 to the second distance D2 reflects the proportion of the at least a portion of the structure of the housing 13 used to combine with the cover plate 11 in the overall structure of the housing 13, and affects the shape and forming process of the rolled portion 1333, thereby affecting the structural strength, structural rationality, and service life of the battery 100.

[0193] In some implementations, the first distance D1 satisfies: 50mm ≤ D1 ≤ 130mm. For example, the first distance D1 can be, but is not limited to, any one or any two of 50mm, 60mm, 70mm, 75mm, 80mm, 90mm, 100mm, 110mm, 120mm, 125mm, and 130mm. In this case, the first distance D1 is more suitable, and the battery 100 can have better portability and practicality.

[0194] The ratio of the first distance D1 to the second distance D2 can be, but is not limited to, any one of 2%, 2.2%, 2.4%, 2.6%, 2.8%, 3%, 3.2%, 3.4%, 3.6%, and 4%, any value between any two of these values, or any value within the range of the above values. When the first distance D1 and the second distance D2 satisfy the above range, the second distance D2 is more suitable under the same first distance D1. The deformation of the coiled part 1333 is smaller, and the possibility of the housing 13 breaking due to deformation during the processing is smaller. This helps to ensure the structural integrity and reliability of the housing 13, while also ensuring a better connection between the housing 13 and the cover plate 11, and reserving space for the sealing ring 15 (described below), thereby improving the structural strength, structural rationality, and service life of the battery 100.

[0195] Please refer to Figure 1 , Figure 2 and Figure 4 In some embodiments, the cover plate 11 includes a first end cover 117 and a second end cover 118. The first end cover 117 and the second end cover 118 are disposed at opposite ends of the housing 13. In the height direction Z, there is a third distance D3 between the outer surface of the first end cover 117 and the outer surface of the second end cover 118, and there is a fourth distance D4 between the protrusion 1332 and the outer surface of the first end cover 117. The third distance D3 and the fourth distance D4 satisfy: D4 / D3≥2%.

[0196] The first end cap 117 and the second end cap 118 are structures in the cover plate 11 that are respectively connected to the two ends of the housing 13 in the height direction Z. The first end cap 117 cooperates with the coiled portion 1333 and the pressing portion 1335 of the housing 13, while the second end cap 118 is directly connected to the end of the housing 13 that does not have the coiled portion 1333. It should be noted that the connection between the second end cap 118 and the housing 13 can be detachable or non-detachable. Typically, the second end cap 118 is welded to the housing 13 to form a reliable housing structure 10. It can be understood that in the height direction Z, the first end cap 117 is closer to the protrusion 1332 than the second end cap 118, and the electrode assembly 30 is disposed between the protrusion 1332 and the second end cap 118.

[0197] This application defines the distance in the height direction Z between the outer surfaces of the first end cap 117 and the second end cap 118 as the third distance D3, and the distance in the height direction Z between the protrusion 1332 and the outer surface of the first end cap 117 as the fourth distance D4. Figure 4 As shown. It should be noted that, in the process of measuring the fourth distance D4, the point where the protrusion 1332 is farthest from the bottom wall 131 of the shell structure 10 is taken as the reference point, and the vertical distance between this point and the outer surface of the first end cover 117 in the height direction Z is measured as the fourth distance D4.

[0198] It can be understood that the third distance D3 is used to represent the overall dimensions of the housing structure 10, i.e., the battery 100, while the fourth distance D4 is used to represent the dimensions and overall shape of at least a portion of the structure of the housing 13 that is used to combine with the first end cap 117 (at least a portion of the coiled portion 1333) in the height direction Z. The ratio of the third distance D3 to the fourth distance D4 reflects the proportion of the at least a portion of the structure of the housing 13 that is used to combine with the first end cap 117 in the overall structure of the housing 13, and affects the shape and forming process of the coiled portion 1333, thereby affecting the structural strength, structural rationality, and service life of the battery 100.

[0199] In some implementations, the third distance D3 satisfies: 60mm ≤ D3 ≤ 115mm. For example, the third distance D3 can be, but is not limited to, any one or any two of 60mm, 65mm, 70mm, 75mm, 80mm, 90mm, 95mm, 100mm, 105mm, 110mm, and 115mm. In this case, the third distance D3 is more suitable, and the battery 100 can have better portability and practicality.

[0200] The ratio of the third distance D3 to the fourth distance D4 can be, but is not limited to, any one, any two of the following: 2%, 2.2%, 2.4%, 2.6%, 2.8%, 3%, 3.2%, 3.4%, 3.6%, and 4%, or any value within the range of the above values. When the third distance D3 and the fourth distance D4 satisfy the above range, the fourth distance D4 is more suitable for the same third distance D3. This results in less deformation of the coiled portion 1333, reducing the likelihood of damage to the housing 13 due to deformation during processing. This helps ensure the structural integrity and reliability of the housing 13, while also ensuring a reliable connection between the housing 13 and the first end cap 117, and allowing space for the installation of the sealing ring 15 (described below), thereby improving the structural strength, structural rationality, and service life of the battery 100.

[0201] Please refer to Figures 1 to 4 In some embodiments, the housing 13 further includes a crimping portion 1335, which is connected to the coiling portion 1333 and together forms a receiving cavity 1337. The crimping portion 1335 includes a first sub-portion 13351 and a second sub-portion 13353, with opposite ends of the first sub-portion 13351 connected to the coiling portion 1333 and the second sub-portion 13353, respectively. The housing structure 10 also includes a sealing ring 15. The sealing ring 15 is at least partially accommodated within the receiving cavity 1337 and is located between the cover plate 11 and the housing 13 to seal the gap between the cover plate 11 and the housing 13.

[0202] In the above-described practical embodiment, the crimping portion 1335 is a structure within the housing 13 used to assist in the connection between the housing 13 and the cover plate 11. It can be understood that the body portion 1331, the crimping portion 1333, and the crimping portion 1335 are all at least part of the sidewall 133 of the housing 13. The crimping portion 1333 and the crimping portion 1335 are connected on the side away from the body portion 1331. In the height direction away from the bottom wall 131, the body portion 1331, the crimping portion 1333, and the crimping portion 1335 are sequentially distributed and interconnected. This application positions the spatial structure formed by the crimping portion 1333 and the crimping portion 1335 within the receiving cavity 1337, as shown below. Figure 3 As shown. It can be understood that the cavity 1337 is connected to the interior of the shell structure 10, and can also be regarded as having a shared space structure between the cavity 1337 and the interior of the shell structure 10.

[0203] The first sub-part 13351 is at least a partial structure connecting the crimping part 1335 and the coiling part 1333. The second sub-part 13353 is a structure in the crimping part 1335 used to cooperate with the coiling part 1333 to jointly fix the cover plate 11. It should be noted that the body part 1331, the coiling part 1333, the first sub-part 13351, and the second sub-part 13353 are generally an integral structure and are formed by steps such as deformation of the housing 13 and sealing with the cover plate 11. The formation steps of the coiling part 1333 will be described in detail below. The first sub-part 13351 is bent and connected to the coiling part 1333. In the extending direction of the first sub-part 13351, the first sub-part 13351 includes two opposite ends, one end of which is connected to the coiling part 1333, and the other end of which is connected to the second sub-part 13353. The second sub-part 13353 is bent and connected to the first sub-part 13351, and the second sub-part 13353 is at least partially spaced from the coiled part 1333 and spaced from the bottom wall 131 of the housing 13.

[0204] Please refer to Figure 3 The periphery of the cover plate 11 is accommodated in the receiving cavity 1337, and a gap exists between it and the housing 13. The sealing ring 15 is a component used to seal the gap between the cover plate 11 and the housing 13. The sealing ring 15 is disposed in the receiving cavity 1337, specifically between the cover plate 11 and the housing 13. Exemplarily, the sealing ring 15 can be made of at least one of the following materials: rubber, silicone, plastic, or synthetic fiber. The rubber material includes, but is not limited to, natural rubber, nitrile rubber, fluororubber, polyurethane rubber, EPDM rubber, or silicone rubber. The sealing ring 15 can prevent external impurities, such as dust and water vapor, from entering the interior through the gap between the cover plate 11 and the housing 13, and can also prevent electrolyte from leaking to the outside through the gap between the cover plate 11 and the housing 13, thus ensuring the service life of the battery 100.

[0205] The forming process of the housing structure 10 will be described below, including the grooving process of the housing 13 and the sealing process of the housing 13 and the cover plate 11. This application uses the grooving process of forming the rolled portion 1333 of the housing 13 as an example for explanation, but this does not constitute a limitation on the processing process of the housing 13. First, the housing 13 is vertically clamped in a fixture, and a preset pressure is applied to the side wall 133 of the housing 13 by one or more radially fed rollers. The rollers roll the side wall 133 of the housing 13, causing the side wall 133 to undergo controllable plastic bending deformation locally, thereby forming a bent structure, namely the rolled portion 1333, at a predetermined height. At this time, the rolled portion 1333 can provide a reference for axial positioning and sealing fit for the subsequent installation of the cover plate 11. After the grooving is completed, the electrode assembly 30 and the like are installed, and the sealing ring 15 and the cover plate 11 are placed into the housing 13 from top to bottom, so that the edge of the cover plate 11 sits above the rolled portion 1333. The sealing process is then carried out: a pressing mold is used to radially narrow or roll the opening of the shell 13, causing the uppermost part of the sidewall 133 to bend inward and press against the edge of the cover plate 11. This part is the pressing part 1335. It can be understood that the pressing part 1335 is a structure formed after the shell 13 and the cover plate 11 are sealed, rather than a structure that can exist in the initial production stage. Similarly, the receiving cavity 1337 is also a spatial structure formed during the sealing process. The synergistic action of the pressing part 1335, the rolling part 1333, and the sealing ring 15 achieves mechanical locking and sealing of the cover plate 11. Throughout the process, the rolling part 1333 provides a support platform, while the pressing part 1335 generates a continuous clamping force. Together, they ensure a reliable connection and airtightness between the cover plate 11 and the shell 13.

[0206] Therefore, in the housing structure 10 of this application, the crimping portion 1333 and the pressing portion 1335 cooperate to form the receiving cavity 1337. The periphery of the cover plate 11 extends into the receiving cavity 1337, and the sealing ring 15 is housed in the receiving cavity 1337 and seals the gap between the cover plate 11 and the housing 13. At this time, the reliability and stability of the connection between the cover plate 11 and the housing 13 are good, and the housing structure 10 has good airtightness, which helps to ensure the safety and service life of the battery 100.

[0207] Please refer to Figures 1 to 3 In some embodiments, in the housing 13, all areas corresponding to the body portion 1331, the coiling portion 1333 and the crimping portion 1335 include a first functional layer 1358, a base layer 1355 and a second functional layer 1359.

[0208] In the above embodiments, it can be understood that the body portion 1331, the coiling portion 1333, and the crimping portion 1335 all include a base layer 1355. When all areas corresponding to the body portion 1331, the coiling portion 1333, and the crimping portion 1335 include the first functional layer 1358 and the second functional layer 1359, the base layer 1355 of all areas of the sidewall 133 of the housing 13 is protected by the first functional layer 1358 and the second functional layer 1359. At this time, the overall corrosion resistance of the housing 13 is excellent, effectively reducing structural damage caused by corrosion at various points on the sidewall 133 of the housing 13, and significantly improving the reliability, safety, and service life of the battery 100.

[0209] Please refer to Figures 1 to 3 In some embodiments, in the housing 13, only the area corresponding to the coiled portion 1333 includes the first functional layer 1358, the base layer 1355, and the second functional layer 1359.

[0210] It is understandable that during the forming process of the coiled portion 1333, at least a portion of the shell 13 forming the coiled portion 1333 deforms under external force to present a predetermined shape. This forming process may cause microcracks or local thinning of the base layer 1355, thereby greatly weakening the corrosion resistance of the base layer 1355 and making it prone to becoming the first area to break. At this time, in order to provide targeted protection for the relatively weak coiled portion 1333, this application only provides a second functional layer 1359 and a first functional layer 1358 on the inner and outer surfaces of the base layer 1355 corresponding to the coiled portion 1333, so that the second functional layer 1359 and the first functional layer 1358 can improve the corrosion resistance of the coiled portion 1333 and prevent the shell 13 from breaking. At this time, the range of the first functional layer 1358 and the second functional layer 1359 is small, which helps to reduce processing costs.

[0211] In the housing structure 10 of this application, only the area corresponding to the coiled portion 1333 includes the first functional layer 1358, the substrate layer 1355, and the second functional layer 1359, so as to protect the relatively weak area corresponding to the coiled portion 1333, and make the battery 100 less likely to fail due to corrosion. The structural integrity and reliability of the housing 13 are better, and the battery 100 improves its service life and safety while also taking into account economy.

[0212] Please refer to Figures 1 to 4 In some embodiments, at least a portion of the cover plate 11 extends into the receiving cavity 1337 and is wrapped by the sealing ring 15.

[0213] Please refer to Figure 3In the above embodiment, the periphery of the cover plate 11 extends into the receiving cavity 1337, and the sealing ring 15 wraps around the periphery of the cover plate 11 and is disposed between the periphery of the cover plate 11 and the pressing part 1333 and the pressing part 1335. For the specific molding method of this embodiment, please refer to the above. At this time, the pressing part 1335, the pressing part 1333, and the cover plate 11 together press the sealing ring 15, thereby effectively realizing the mechanical locking and sealing of the cover plate 11, ensuring reliable connection and airtightness between the cover plate 11 and the housing 13.

[0214] Therefore, in the housing structure 10 of this application, when the periphery of the cover plate 11 extends into the receiving cavity 1337 and is wrapped by the sealing ring 15, the sealing ring 15 can effectively seal the gap between the cover plate 11 and the housing 13. At this time, the sealing ring 15 fills a large range of the gap between the cover plate 11 and the housing 13, and the sealing effect is good, effectively ensuring the airtightness of the housing structure 10 and ensuring that the battery 100 has good safety performance and a long service life.

[0215] Please refer to Figure 1 , Figure 2 , Figures 5 to 10 In some embodiments, a constraint space is formed on the sidewall 133 of the housing 13 or the cover plate 11, and the sealing ring 15 is accommodated within the constraint space, including a first side 1501 and a second side 1503 that are radially opposite, and a third side 1505 and a fourth side 1507 that are axially opposite. The peripheral wall of the constraint space is used to limit and abut against three of the first side 1501, the second side 1503, the third side 1505, and the fourth side 1507. When the constraint space is formed on the sidewall 133 and the cover plate 11 is connected to the housing 13, the cover plate 11 limits and abuts against the other side of the first side 1501, the second side 1503, the third side 1505, and the fourth side 1507. A constraint space is formed on the cover plate 11, and when the cover plate 11 is connected to the housing 13, the side wall 133 limits and abuts against the other side of the first side 1501, the second side 1503, the third side 1505 and the fourth side 1507.

[0216] Please refer to Figures 5 to 10 , Figures 5 to 10 The document shows six implementation methods, respectively, and Figure 3 The diagram shown is a partially enlarged view of the same section. Figures 5 to 10 For simplicity, the detailed structure of the sidewall 133 is not shown, i.e., the base layer 1355 and the functional layer 1357 are not shown. It can be understood that at this point, in... Figures 5 to 10 Of the six implementation methods, the implementation methods described above (i.e.) Figure 3 (The embodiments shown are similar), the sidewall 13 includes a base layer 1355 and a functional layer 1357.

[0217] The constraint space is a recessed area located on the sidewall 133 or the cover plate 11, used to accommodate the sealing ring 15 and restrict its displacement in multiple directions. The boundary of the constraint space is formed by the peripheral wall provided by the sidewall 133 or the cover plate 11. The peripheral wall includes at least three interconnected inner wall surfaces, each facing a different direction. The constraint space is not a simple through slot, but a cavity with a closed circumferential direction.

[0218] The constraint space can be formed in several ways. When the constraint space is located on the cover plate 11, a groove 1130 can be pressed from one surface of the cover plate 11 to the other surface using a stamping process, and the bottom surface and side wall 133 of the groove 1130 form the peripheral wall. When the constraint space is located on the side wall 133, the receiving cavity 1337 formed by the rolled part 1333 and the pressing part 1335 constitutes the constraint space. In an alternative embodiment, the constraint space can also be formed directly by machining (such as milling) on ​​the cover plate 11 or the housing 13.

[0219] At this point, the sealing ring 15 is an annular elastic body, and its cross-sectional shape can be rectangular, circular, O-shaped, or D-shaped. Please refer to [reference needed]. Figures 5 to 10 The cross-section of the sealing ring 15 is shown as approximately rectangular, a shape that facilitates stable surface contact with a flat peripheral wall within a constrained space. The sealing ring 15 includes four functional sides. The first side 1501 and the second side 1503 are radially opposed. Radial refers to the direction perpendicular to the central axis of the housing 13, pointing from the center of the housing structure 10 to the outside of the housing 13. The first side 1501 generally faces the center of the housing structure 10, and the second side 1503 faces the side wall 133 of the housing 13. The third side 1505 and the fourth side 1507 are axially opposed. Axial refers to the direction parallel to the central axis of the housing structure 10, pointing from the bottom wall 131 of the housing 13 to the cover plate 11. The third side 1505 faces the center of the housing structure 10, and the fourth side 1507 faces the outside of the housing 13 (i.e., towards the outside of the cover plate 11).

[0220] The peripheral wall of the constraint space is used to limit and abut against three of the four sides of the sealing ring 15. Limiting and abutting means that two surfaces come into contact with each other and prevent one from moving further in a specific direction. Limiting and abutting does not require an interference fit; it only requires that the two surfaces physically block each other in a predetermined direction. For example, if one side of the peripheral wall contacts the first side 1501 of the sealing ring 15, then the sealing ring 15 cannot move further in the direction of the first side 1501, but can move in the opposite direction (i.e., away from the peripheral wall). Unlike an interference fit, limiting and abutting allows for small gaps in non-stressed directions, thus reducing the requirements for dimensional accuracy of the parts.

[0221] The peripheral wall simultaneously provides limiting contact with three sides, meaning that the sealing ring 15 is mechanically locked in three degrees of freedom within the constrained space. For example: suppose the peripheral wall abuts against the first side 1501, the second side 1503, and the third side 1505 (e.g., ...). Figure 5 (As shown). Therefore, the sealing ring 15 cannot move radially inward (blocked by the peripheral wall of the first side 1501), cannot move radially outward (blocked by the peripheral wall of the second side 1503), and cannot move axially inward towards the interior of the housing 13 (blocked by the peripheral wall of the third side 1505). The sealing ring 15 is left with only one unrestricted degree of freedom in the axial outward direction (the direction of the fourth side 1507). In the unassembled state, the sealing ring 15 is firmly fixed within the constrained space and will not fall off or tilt due to gravity or slight vibration.

[0222] During the pressing and assembly of the cover plate 11 and the housing 13, the side not abutted by the constrained space (e.g., the fourth side 1507) will come into contact with and be pushed by a corresponding structure on the housing 13 or the cover plate 11. This corresponding structure can be the second sub-part 13353 of the pressing part 1335 of the housing 13, in which case a constrained space is formed on the cover plate 11; or it can be the first abutting sub-part 1137 of the cover plate 11 (described below), in which case a constrained space is formed on the side wall 133. It can be understood that the structure that limits and abuts the side not abutted by the constrained space (e.g., the fourth side 1507) depends specifically on the position and orientation of the constrained space.

[0223] Once the cover plate 11 and the housing 13 are fully engaged, this corresponding structure applies a clamping force to the free side, forcing the sealing ring 15 to undergo elastic compression in that direction. Since the other three sides are confined by the peripheral wall, the sealing ring 15 cannot bulge or shift in other directions; the compression deformation is constrained to a single direction. A rebound stress is generated inside the sealing ring 15, perpendicular to the compressed side, acting on the contact surface of the housing 13 or the cover plate 11, forming a sealing pressure.

[0224] Before assembly begins, the sealing ring 15 is placed in the constraint space or a space corresponding to the constraint space. The housing 13 and / or the cover plate 11 abut against at least two sides of the sealing ring 15, securing the sealing ring 15 in a predetermined position. The sealing ring 15 will not fall off, will not be misaligned, and will not shift during subsequent operations.

[0225] Subsequently, the cover plate 11 (if the constraint space is on the side wall 133) or the housing 13 (if the constraint space is on the cover plate 11) is assembled with the other. During the pressing process, a free side gradually comes into contact with the abutment surface of the opposite part. As the pressing depth increases, this free side is subjected to thrust, and the sealing ring 15 is compressed in this direction.

[0226] Since the initial position of the sealing ring 15 is precisely defined by the constraint space and the compression direction is unique, the amount of compression of the sealing ring 15 depends only on the relative displacement between the cover plate 11 and the housing 13 along this direction. This displacement is determined by the axial clearance between the housing 13 and the cover plate 11, or by the radial clearance between the housing 13 and the cover plate 11, and is independent of the tolerances in other directions (such as the inner diameter of the housing 13, the outer diameter of the cover plate 11, and the inner diameter of the sealing ring 15). Compared to the sealing ring 15 being directly clamped between the housing 13 and the cover plate 11, this application achieves pre-positioning through the constraint space, leaving only one direction to participate in the compression assembly, breaking the coupling of tolerances in other directions, thereby achieving precise control of the compression amount.

[0227] Therefore, in the housing structure 10 of this application, by setting a constraint space, the sealing ring 15 is pre-positioned before assembly, and no offset or flipping occurs during the assembly process; at the same time, when the cover plate 11 and the housing 13 are sealed, the sealing ring 15 is compressed only in the direction corresponding to one side to provide the main sealing force, while in the other directions it is limited only by the constraint space and does not rely on interference fit to achieve sealing. This avoids the problem that the compression amount of the sealing ring 15 is difficult to control precisely due to the superposition of dimensional tolerances, thereby improving the sealing reliability and process stability, and increasing the production yield.

[0228] Please refer to Figure 1 , Figure 3 , Figures 5 to 8 In some embodiments, the cover plate 11 includes a cover plate body 111 and a limiting portion 113. The constraint space includes a groove 1130 on the limiting portion 113, the groove 1130 including a groove bottom wall 11301 and a circumferential side wall 11303 connected to the groove bottom wall 11301. The sealing ring 15 is accommodated in the groove 1130, the circumferential side wall 11303 is used to limit and abut against the first side 1501 and the second side 1503 of the sealing ring 15, the groove bottom wall 11301 is used to limit and abut against one of the third side 1505 and the fourth side 1507, and the side wall 11303 is used to limit and abut against the other of the third side 1505 and the fourth side 1507.

[0229] The cover body 111 is the main part of the cover 11, and is the largest flat plate area in the cover 11, serving as the structural base of the entire cover 11. The cover body 111 maintains a basically straight shape and is used to mate with the side wall 133 or the pressing part 1335 of the housing 13, while also bearing the assembly pressure. The limiting part 113 is a structure in the cover 111 used to limit the sealing ring 15. The cover body 111 and the limiting part 113 can be an integral structure or a separate structure. When the cover body 111 and the limiting part 113 are separate structures, the connection between the cover body 111 and the limiting part 113 can be a detachable connection or a non-detachable connection.

[0230] The groove 1130 is a spatial structure located on the limiting portion 113, used to place the sealing ring 15 and provide limiting in multiple directions. The groove 1130 includes a groove bottom wall 11301 and a circumferential side wall 11303. The groove bottom wall 11301 is the innermost supporting wall of the groove 1130, and the surface of the groove bottom wall 11301 is parallel or substantially parallel to the main plane of the cover plate body 111. The circumferential side wall 11303 is an annular wall extending from the edge of the groove bottom wall 11301 toward the surface of the cover plate 11. The circumferential side wall 11303 can be a straight wall perpendicular to the groove bottom wall 11301, or it can be an inclined wall with a slight draft angle.

[0231] The circumferential sidewall 11303 is used to limit and abut against the first side 1501 and the second side 1503 of the sealing ring 15. That is, after the sealing ring 15 is placed in the groove 1130, the radially inward side (first side 1501) and the radially outward side (second side 1503) respectively contact the two opposing wall surfaces of the circumferential sidewall 11303. The circumferential sidewall 11303 prevents the sealing ring 15 from moving radially within the groove 1130, fixing it in place whether it is towards the center of the battery 100 or towards the sidewall 133 of the housing 13. This radial bidirectional limiting is the key difference between the groove 1130 and a simple countersunk hole or a platform without sidewalls. The circumferential sidewall 11303 and the sealing ring 15 can be a slight interference fit or a transition fit with a small gap, but the gap should be less than the radial deformation that may occur when the sealing ring 15 is compressed, to prevent the sealing ring 15 from coming out of the groove 1130.

[0232] The bottom wall 11301 of the groove is used to limit and abut against one of the third side 1505 and the fourth side 1507. Whether it abuts against the third side 1505 or the fourth side 1507 depends on the opening direction of the groove 1130. If the opening of the groove 1130 faces the outside of the housing 13, then the bottom wall 11301 abuts against the third side 1505 (the side facing the inside of the housing 13), and the fourth side 1507 is the free side relative to the cover plate 11. Figure 5 and Figure 7 As shown. If the opening of the groove 1130 faces the interior of the housing 13, then the bottom wall 11301 of the groove abuts against the fourth side 1507 (the side facing the outside of the cover plate 11), and the third side 1505 is the free side relative to the cover plate 11, as shown. Figure 6 and Figure 8 As shown, the bottom wall 11301 of the groove provides a flat axial support surface for the sealing ring 15, so that the sealing ring 15 can be evenly stressed during compression and avoid local stress concentration.

[0233] The side wall 133 is used to limit and abut the side of the third side 1505 and the fourth side 1507 that is not abutted by the bottom wall 11301 of the groove. The structure on the side wall 133 that participates in the abutment can be the top surface of the rolled part 1333 or the bottom surface of the second sub-part 13353. After the cover plate 11 is pressed into place, the corresponding structure of the housing 13 contacts the free side of the sealing ring 15 and applies pressure, forcing the sealing ring 15 to be compressed axially.

[0234] In the sealing structure employing the groove 1130 design, the assembly process is as follows: First, the sealing ring 15 is placed into the groove 1130 of the cover plate 11. The circumferential sidewall 11303 of the groove 1130 contacts the first side 1501 and the second side 1503 of the sealing ring 15, preventing the sealing ring 15 from moving radially. The bottom wall 11301 of the groove abuts against the third side 1505 (or the fourth side 1507) of the sealing ring 15, limiting the sealing ring 15 axially towards the interior of the groove 1130. At this point, the sealing ring 15 is fixed to the cover plate 11, and even if the cover plate 11 is flipped or vibrated, the sealing ring 15 will not fall off.

[0235] Then, the cover plate 11 with the sealing ring 15 is combined with the housing 13. The crimping portion 1333 or crimping portion 1335 of the housing 13 gradually approaches the side of the sealing ring 15 that is not abutted by the bottom wall 11301 of the groove. When the housing 13 and the cover plate 11 are pressed into a predetermined position, the corresponding structure of the housing 13 contacts the free side and pushes the sealing ring 15, causing the sealing ring 15 to be compressed axially. After compression, the sealing ring 15 generates a rebound force between the bottom wall 11301 of the groove and the housing 13. This rebound force is applied axially to the two contact surfaces, forming a sealing pressure.

[0236] Because the radial sides of the sealing ring 15 are limited by the circumferential sidewalls 11303 and the axial side is limited by the groove bottom wall 11301, the sealing ring 15 can only deform axially toward the housing 13 during compression, and there will be no radial bulging or twisting. The amount of compression of the sealing ring 15 is equal to the axial distance between the groove bottom wall 11301 and the abutment surface of the housing 13 minus the thickness of the sealing ring 15 after compression. This distance is determined by the axial fit dimensions of the cover plate 11 and the housing 13 and is not affected by the radial dimension fluctuations of the sealing ring 15.

[0237] At this point, compared to the solution of simply placing the sealing ring 15 into a shallow groove without bidirectional limiting on both radial sides, the sealing ring 15 is prone to radial slippage during the compression process, causing it to deviate from its intended position or even be squeezed into the gap between the cover plate 11 and the housing 13, resulting in damage. This application eliminates the possibility of radial movement by simultaneously limiting both radial sides of the sealing ring 15 through the circumferential sidewall 11303 of the groove 1130, ensuring the positional stability of the sealing ring 15 during compression.

[0238] Therefore, in the housing structure 10 of this application, a groove 1130 is provided on the limiting part 113 of the cover plate 11. The circumferential sidewall 11303 of the groove 1130 provides radial bidirectional limiting for the first side 1501 and the second side 1503 of the sealing ring 15. The bottom wall 11301 of the groove provides axial unilateral limiting for the third side 1505 or the fourth side 1507. The housing 13 then provides axial limiting for the other side and compresses the sealing ring 15. This ensures that the sealing ring 15 is pre-positioned on the cover plate 11 before assembly, and the sealing ring 15 will not experience radial displacement or axial detachment during assembly. At the same time, the sealing ring 15 is only compressed axially, and the amount of compression depends only on the axial assembly dimensions of the cover plate 11 and the housing 13. This avoids the influence of radial dimensional tolerances on the compression amount of the sealing ring 15, thereby simplifying the tolerance chain and improving sealing reliability and production consistency.

[0239] Please refer to Figure 1 , Figure 3 , Figure 5 and Figure 6 In some embodiments, the groove 1130 is formed by bending the cover plate 11. The limiting part 113 includes a first bending part 1131, a groove bottom part 1133 and a second bending part 1135. The two ends of the groove bottom part 1133 are respectively connected to the first bending part 1131 and the second bending part 1135, and together with the first bending part 1131 and the second bending part 1135, they form the groove 1130.

[0240] The first bend portion 1131 is a wall panel formed by bending and extending from the edge of the cover plate body 111. The extension direction of the first bend portion 1131 is perpendicular to or approximately perpendicular to the cover plate body 111. The first bend portion 1131 and the cover plate body 111 are connected by an arc transition. The first bend portion 1131 is used to connect the cover plate body 111 and the groove bottom portion 1133, and its inner surface forms one circumferential sidewall 11303 of the groove 1130.

[0241] The second bent portion 1135 is a wall panel formed by bending and extending from the other end of the groove bottom portion 1133. The extension direction of the second bent portion 1135 is perpendicular to or approximately perpendicular to the groove bottom portion 1133. The second bent portion 1135 is disposed opposite to the first bent portion 1131, and the two are parallel or nearly parallel to each other. The inner surface of the second bent portion 1135 forms the other circumferential sidewall 11303 of the groove 1130. The outer surface 1353 of the second bent portion 1135 abuts against the first portion 13351 during assembly to transmit the pressing force.

[0242] The bottom portion 1133 is a flat bottom wall connecting the first bent portion 1131 and the second bent portion 1135. Both ends of the bottom portion 1133 are connected to the first bent portion 1131 and the second bent portion 1135 via arc transitions. The bottom portion 1133, the first bent portion 1131, and the second bent portion 1135 together form a rectangular groove 1130. The width of the bottom portion 1133 is radial along the cover plate 11, and its length is circumferential along the cover plate 11. The surface of the bottom portion 1133 supports the axial end face of the sealing ring 15.

[0243] In some embodiments, the first bending portion 1131, the groove bottom portion 1133, and the second bending portion 1135 are integrally formed from the same metal sheet through a continuous bending process. In this case, the raw material for the cover plate 11 is a flat metal sheet. First, the shape is punched out at a predetermined position, and then it is sequentially bent using a mold to form the first bending portion 1131, the groove bottom portion 1133, and the second bending portion 1135. During the bending process, the metal material undergoes plastic deformation, and a rounded chamfer is formed in the bending transition area to reduce stress concentration, prevent cracking at the bend, and prevent the sealing ring 15 from being cut by sharp edges. In other embodiments, the cover plate 11 can also be formed into a similar groove shape using a stamping and stretching method.

[0244] Therefore, in the housing structure 10 of this application, the first bending portion 1131, the groove bottom portion 1133, and the second bending portion 1135 together form a groove 1130, ensuring good perpendicularity and high dimensional accuracy of the two adjacent structures that bend and connect to form the groove 1130. This allows for precise radial positioning of the first side 1501 and the second side 1503 of the sealing ring 15, and the groove bottom portion 1133 provides stable axial support for the third side 1505 or the fourth side 1507 of the sealing ring 15. The bending process does not reduce the material thickness, and the groove 1130 has high overall strength, capable of withstanding the lateral forces generated during the pressing process without deformation. Simultaneously, the bent groove 1130 can be fully embedded into the receiving cavity 1337 of the housing 13, making full use of the internal space of the housing structure 10 without increasing the overall height of the battery 100, which is beneficial for the compact design and improved energy density of the battery 100.

[0245] Please refer to Figure 5 In some embodiments, the first bending portion 1131, the groove bottom portion 1133, and the second bending portion 1135 are housed in the receiving cavity 1337. The second bending portion 1135 abuts against the first portion 13351, the third side 1505 abuts against the bottom wall of the groove 11301, the fourth side 1507 abuts against the second portion 13353, the groove bottom portion 1133 abuts against the rolling portion 1333, and at least a portion of the cover plate body 111 abuts against the second portion 13353.

[0246] Please refer to Figure 6 In other embodiments, the first bending portion 1131, the groove bottom portion 1133, and the second bending portion 1135 are housed in the receiving cavity 1337. The second bending portion 1135 abuts against the first portion 13351, the third side 1505 abuts against the coiling portion 1333, the fourth side 1507 abuts against the bottom wall 11301 of the groove, and the groove bottom portion 1133 abuts against the second portion 13353.

[0247] Please refer to Figure 1 , Figure 3 , Figure 7 and Figure 8 In some embodiments, the cover plate 11 includes a first surface 114 and a second surface 115 opposite each other in the thickness direction, the first surface 114 facing the interior of the housing 13 and the second surface 115 facing the exterior of the housing 13, and the groove 1130 is formed by one of the first surface 114 and the second surface 115 at the limiting portion 113 being recessed into the other.

[0248] The first surface 114 is the surface of the cover plate 11 facing the interior of the housing 13. The second surface 115 is the surface of the cover plate 11 facing the exterior of the housing 13, i.e., facing the external environment. The first surface 114 and the second surface 115 are relatively parallel or substantially parallel in the thickness direction of the cover plate 11, and the vertical distance between them is the thickness of the cover plate 11. It can be understood that the thickness direction of the cover plate 11 is the height direction Z of the housing 13.

[0249] The groove 1130 is formed by recessing from one of the first surface 114 and the second surface 115 towards the other. There are two specific scenarios. The first scenario: the groove 1130 is recessed from the second surface 115 (outer surface) towards the first surface 114 (inner surface), meaning the opening of the groove 1130 faces the outside of the housing 13, and the bottom wall 11301 of the groove is closer to the first surface 114 (inner surface). Figure 7 As shown. In the second case: the groove 1130 is recessed from the first surface 114 (inner surface) towards the second surface 115 (outer surface), that is, the opening of the groove 1130 faces the inside of the housing 13, and the bottom wall 11301 of the groove is closer to the second surface 115 (outer surface), as shown. Figure 8 As shown.

[0250] The groove 1130 can be formed by a stamping process. The flat blank of the cover plate 11 is placed into the stamping die, and the punch presses in from one side, causing the metal material to flow plastically, forming a protrusion or depression on the other side. After stamping, the circumferential sidewall 11303 and the bottom wall 11301 of the groove 1130 are both continuous and complete metal surfaces, without seams or welding marks.

[0251] In the sealing structure employing a stamped groove 1130, after the sealing ring 15 is placed into the groove 1130, the circumferential sidewall 11303 radially limits the first side 1501 and the second side 1503 of the sealing ring 15. The bottom wall 11301 of the groove axially limits one of the third side 1505 or the fourth side 1507. The housing 13 axially limits the other side and compresses the sealing ring 15.

[0252] Therefore, in the housing structure 100 of this application, the groove 1130 does not change the overall outline of the cover plate 11, and the cover plate 11 remains flat, facilitating automated feeding and assembly. The minimum distance between the bottom of the groove 1130 (groove bottom wall 11301) and the other surface of the cover plate 11, i.e., the remaining wall thickness, can be adjusted by controlling the stamping depth. The groove 1130 is suitable for mass production, with high production efficiency and good dimensional consistency.

[0253] Please refer to Figure 7 In some embodiments, the cover plate 11 further includes a peripheral side surface 116, which connects the first surface 114 and the second surface 115. The second surface 115 and the fourth side 1507 abut against the second sub-part 13353, the peripheral side surface 116 abuts against the first sub-part 13351, and the first surface 114 abuts against the rolled portion 1333.

[0254] Please refer to Figure 8 In some embodiments, the cover plate 11 further includes a peripheral side 116, which connects the first surface 114 and the second surface 115. The second surface 115 abuts against the second sub-part 13353, the peripheral side 116 abuts against the first sub-part 13351, and the first surface 114 and the third side 1505 abut against the coiled portion 1333.

[0255] Please refer to Figures 5 to 8 In some embodiments, the depth Dp1 of the groove 1130 in the thickness direction of the cover plate 11 ranges from 0.15mm ≤ Dp1 ≤ 2.50mm. In this case, the depth of the groove 1130 is moderate. This depth is sufficient to accommodate most of the thickness of the sealing ring 15, ensuring that the sealing ring 15 is firmly pre-positioned within the groove 1130 before assembly and is not easily dislodged. The circumferential sidewalls 11303 of the groove 1130 effectively limit the radial sides of the sealing ring 15, preventing radial bulging during compression. Simultaneously, the remaining wall thickness of the cover plate 11 in the groove 1130 region maintains sufficient strength and will not deform during pressing.

[0256] Please refer to Figures 5 to 8In some embodiments, the length S1 of the first contact surface between the sealing ring 15 and the housing 13 along the radial direction of the sealing ring 15 is in the range of 0.50mm ≤ S1 ≤ 12.00mm. This avoids both insufficient radial support area of ​​the sealing ring 15 due to an excessively small S1, resulting in weak limiting constraint, and excessively large radial contact area, which would significantly increase the overall material consumption of the sealing ring 15, thereby leading to excessive raw material consumption and increased manufacturing costs.

[0257] Please refer to Figures 5 to 8 In some embodiments, the sealing ring 15 and the cover plate 11 have a second contact surface that contacts each other, and the extension dimension S2 of the second contact surface ranges from 0.50mm ≤ S2 ≤ 12.00mm. Please refer to [reference needed]. Figures 5 to 8 S2 = S21 + S22 + S23, where S21 is the axial length of the second contact surface, S22 is the radial length of the second contact surface, and S23 is the remaining axial length of the second contact surface. When the value of S2 is within the above range, the radial fit dimension of the sealing ring 15 is reasonable, the contact area between the cover plate 11 and the sealing ring 15 is properly matched, and the cover plate 11 can provide stable lateral restraint and effective constraint on radial displacement of the sealing ring 15, while also preventing the sealing ring 15 from skewing or shifting. This avoids S2 being too small, which would result in weak radial constraint of the cover plate 11 on the sealing ring 15, making the sealing ring 15 prone to radial displacement and overturning misalignment after being compressed; it also avoids S2 being too large, which would lead to an excessively large radial fit area of ​​the sealing ring 15, significantly increasing the overall material consumption of the sealing ring 15 and raising production costs.

[0258] Please refer to Figures 5 to 8 In some embodiments, the axial thickness T5 of the sealing ring 15 ranges from 0.25mm to 3.00mm. The axial thickness of the sealing ring 15 is reasonable and has sufficient elastic compression allowance. After compression, the sealing ring 15 can achieve stable deformation to fill the gap, ensuring a tight fit between the sealing surfaces. This avoids situations where a T5 is too small, preventing the sealing ring 15 from fully filling the assembly gap and resulting in an incomplete seal, which could lead to problems such as leakage and dust ingress into the battery 100. It also avoids situations where a T5 is too large, increasing the material required for the sealing ring 15 and thus saving manufacturing costs.

[0259] Please refer to Figures 5 to 8In some embodiments, the remaining thickness ratio Rt of the sealing ring 15 is in the range of 40% ≤ Rt ≤ 90%. When Rt is within the above range, the elastic compression ratio of the sealing ring 15 is just right, and the sealing ring 15 fully fills the assembly gap, resulting in excellent sealing performance of the battery 100. At the same time, the sealing ring 15 retains sufficient rebound margin so that it can maintain elasticity even under long-term pressure. This avoids Rt being too small, which would cause the sealing ring 15 to be over-compressed and its deformation to approach its limit, making it unable to relieve force when subjected to external force, thus significantly reducing the protective performance of the battery 100. This also avoids Rt being too large, which would result in insufficient actual compression of the sealing ring 15 and insufficient contact between the sealing ring 15 and the sealing surface, leading to poor sealing of the battery 100 and easy occurrence of dust ingress, water seepage, and liquid leakage.

[0260] Please refer to Figure 1 , Figure 3 , Figure 9 and Figure 10 In some embodiments, the constrained space is a receiving cavity 1337, the peripheral wall of which is used to limit and abut against the third side 1505 and the fourth side 1507, and the pressing part 1335 is used to limit and abut against one of the first side 1501 and the second side 1503. The cover plate 11 includes a cover plate body 111 and a limiting part 113, which bends and extends from the cover plate body 111 and is used to limit and abut against the other of the first side 1501 and the second side 1503.

[0261] The receiving cavity 1337, as a structural form of constrained space, can be used to accommodate the sealing ring 15. After the sealing ring 15 is placed in the receiving cavity 1337, the peripheral wall of the receiving cavity 1337 limits and abuts against the third side 1505 and the fourth side 1507 of the sealing ring 15. That is, both sides of the sealing ring 15 in the axial direction are abutted by the peripheral wall of the receiving cavity 1337. In other words, the sealing ring 15 cannot move in the axial direction, and its axial position is completely fixed.

[0262] The crimping portion 1335 is used to limit and abut one of the first side 1501 and the second side 1503. The first side 1501 and the second side 1503 are two radially opposite sides of the sealing ring 15. The crimping portion 1335 abuts against one of the sides (e.g., the first side 1501, i.e., the side facing the center of the housing 13), preventing the sealing ring 15 from moving in that direction.

[0263] The cover plate 11 includes a cover plate body 111 and a limiting portion 113. The cover plate body 111 is the main flat plate area of ​​the cover plate 11, used to close the opening of the housing 13. The limiting portion 113 is also a structure used to limit at least part of the sealing ring 15. The limiting portion 113 includes a first abutting portion 1137, which is a wall plate formed by bending and extending from the edge of the cover plate body 111, with its extension direction perpendicular or approximately perpendicular to the cover plate body 111. The first abutting portion 1137 and the cover plate body 111 are connected by an arc transition. The first abutting portion 1137 and the pressing portion 1335 are disposed opposite each other, with a gap between them, in which the sealing ring 15 is placed.

[0264] The first abutment portion 1137 is used to limit the contact between the first side 1501 and the other side 1503. That is, if the crimping portion 1335 abuts against the first side 1501, then the first abutment portion 1137 abuts against the second side 1503 (the side facing outward of the housing 13); and vice versa. The crimping portion 1335 and the first abutment portion 1137 together clamp the radial sides of the sealing ring 15, preventing the sealing ring 15 from moving radially.

[0265] At this point, the third side 1505 and the fourth side 1507 of the sealing ring 15 are completely confined axially by the peripheral wall of the receiving cavity 1337, while the first side 1501 and the second side 1503 are completely confined radially by the pressing part 1335 and the first abutting part 1137. All four sides of the sealing ring 15 are confined and abutted, with no free sides. At this time, the sealing ring 15 does not generate sealing pressure through compression, but rather achieves sealing through radial or axial interference fit.

[0266] During assembly, a grooving process is first used to form a pressing portion 1333, on which the sealing ring 15 is supported. At this point, the position of the sealing ring 15 corresponds to the position of the subsequently formed receiving cavity 1337. The side wall 133 of the housing 13 will at least abut against the third side 1505 of the sealing ring 15 to support and initially fix the sealing ring 15 axially. Then, the cover plate 11 is placed into the housing 13. The first abutting portion 1137 of the cover plate 11 corresponds to the position of the subsequently formed receiving cavity 1337 and contacts the first side 1501 or the second side 1503 of the sealing ring 15. When the cover plate 11 is pressed into place, the first abutting portion 1137 and the formed pressing portion 1335 together clamp the radial sides of the sealing ring 15, forming a radial seal.

[0267] Therefore, in the housing structure 10 of this application, the constraint space is set as a receiving cavity 1337 formed by the pressing part 1333 and the pressing part 1335. The peripheral wall of the receiving cavity 1337 is used to limit the third side 1505 and the fourth side 1507 of the sealing ring 15 in both axial directions. The pressing part 1335 and the first abutting part 1137 of the cover plate 11 are used to limit the first side 1501 and the second side 1503 of the sealing ring 15 in both radial directions, so that all four sides of the sealing ring 15 are limited and abutted. The sealing ring 15 cannot move in either the axial or radial direction, and the assembly position is precisely fixed.

[0268] Please refer to Figure 9 In some embodiments, the limiting portion 113 further includes a second abutting portion 1139, which extends and bends from the first abutting portion 1137 and is spaced apart from the cover plate body 111 in the thickness direction of the cover plate 11. The second abutting portion 13353 abuts against one of the third side 1505 and the fourth side 1507, and the coiling portion 1333 abuts against the other of the third side 1505 and the fourth side 1507. The second abutting portion 1139 abuts against the second abutting portion 13353, and the cover plate body 111 abuts against the coiling portion 1333.

[0269] Please refer to Figure 10 In some embodiments, the limiting portion 113 further includes a second abutting portion 1139, which extends and bends from the first abutting portion 1137 and is spaced apart from the cover plate body 111 in the thickness direction of the cover plate 11. The second abutting portion 13353 abuts against one of the third side 1505 and the fourth side 1507, and the coiling portion 1333 abuts against the other of the third side 1505 and the fourth side 1507. The cover plate body 111 abuts against the second abutting portion 13353, and the second abutting portion 1139 abuts against the coiling portion 1333.

[0270] Please refer to Figure 9 and Figure 10 In some embodiments, the maximum distance Dp2 between the second abutment portion 1139 and the cover body 111 ranges from 0.20mm ≤ Dp2 ≤ 6.00mm. This ensures reasonable space utilization within the battery 100, preventing an additional increase in the overall dimensions of the battery 100 and resulting in a compact product structure. Conversely, a value of Dp2 that is too small would cause the abutment distance between the second abutment portion 1139 and the cover body 111 to be too close, increasing the difficulty of forming the cover 11 structure and making it prone to springback deformation at bends. Similarly, a value of Dp2 that is too large would result in an excessively large gap between the second abutment portion 1139 and the cover body 111, increasing the overall structural space required and manufacturing costs.

[0271] Please refer to Figure 9 and Figure 10 In some embodiments, the sealing ring 15 and the housing 13 have a first contact surface, and the extension dimension S3 of the first contact surface ranges from 0.50mm ≤ S3 ≤ 12.00mm. In this case, the contact length between the sealing ring 15 and the housing 13 is reasonable and the sealing surfaces are fully fitted, ensuring stable and reliable sealing and dustproof performance of the battery 100. This avoids the situation where the value of S3 is too small, causing the stress on the sealing structure to concentrate in a narrow area, resulting in excessive local pressure on the sealing structure, which could easily cause localized indentation and deformation and accelerate the aging and wear of the battery 100. It also avoids the situation where the value of S3 is too large, resulting in an excessively large contact area between the sealing ring 15 and the housing 13, which would increase the material required for the sealing ring 15 and directly increase production costs.

[0272] Please refer to Figure 9 and Figure 10 In some embodiments, the sealing ring 15 and the cover plate 11 have a second contact surface that contacts each other, and the extension dimension S4 of the second contact surface ranges from 0.50mm to 12.00mm. Please refer to [reference needed]. Figure 9 and Figure 10 S4 = S41 + S42 + S43, where S41 is the axial length of the second contact surface, S42 is the radial length of the second contact surface, and S43 is the remaining axial length of the second contact surface. At this point, the axial pressure area of ​​the sealing ring 15 is uniform, the compression deformation of the sealing ring 15 is regular, and the sealing ring 15 and the cover plate 11 are tightly sealed, ensuring stable anti-leakage and dustproof performance of the battery 100. This avoids a value of S4 that is too small, causing the force on the sealing ring 15 to concentrate in a narrow area, resulting in excessive local pressure on the sealing ring, which could easily cause local indentation deformation and accelerate the aging and wear of the battery 100. Conversely, it also avoids a value of S4 that is too large, resulting in an excessively large contact area between the sealing ring 15 and the cover plate 11, which would increase the material required for the sealing ring 15 and directly increase production costs.

[0273] Please refer to Figure 9 and Figure 10 The radial thickness T6 of the sealing ring 15 ranges from 0.10mm to 3.50mm. When T6 falls within this range, the radial thickness of the sealing ring 15 is moderate, the radial support strength of the sealing ring 15 is sufficient, the sealing ring 15 can stably fill the radial fit gap and provide a tight circumferential seal, resulting in excellent leak-proof and dust-proof performance for the battery 100. This avoids a T6 value that is too small, leading to low pressure resistance of the sealing ring 15, which would make the battery 100 prone to seal failure and leakage when internal air pressure fluctuates. Conversely, a T6 value that is too large would significantly increase the amount of raw materials used in the sealing ring 15, resulting in a substantial increase in production costs.

[0274] Similarly, in Figure 9 and Figure 10 In the corresponding implementation, the axial thickness T5 of the sealing ring 15 is also satisfied, with a range of 0.25mm ≤ T5 ≤ 3.00mm. Furthermore, the remaining thickness ratio of the sealing ring 15 is in the range of 40% ≤ Rt ≤ 90%. For specific properties and beneficial effects, please refer to the description above; further details will not be repeated here.

[0275] Please refer to Figures 5 to 10 In some embodiments, the compressive modulus E of the sealing ring 15 is in the range of 0.50MPa≤E≤30.00MPa at room temperature and pressure. In this case, the elastic modulus of the sealing ring 15 is moderate and can accurately match the assembly compression amount. The sealing ring 15 can easily fill the mating gap, and the battery 100 is tightly and stably sealed.

[0276] Please refer to Figure 1 and Figure 2 Secondly, this application provides a battery, specifically a battery 100. The battery 100 includes a housing structure 10 and an electrode assembly 30 as described in any of the above embodiments. The electrode assembly 30 is housed within the housing structure 10.

[0277] In the above practical method, it should be noted that the specific structure and properties of the battery 100 and the housing structure 10 in this embodiment are exactly the same as those in the above embodiments, and will not be explained again here.

[0278] The electrode assembly 30 is the core component of the battery 100 that enables energy storage and release. In the battery 100, the electrode assembly 30 is typically housed and encapsulated within the casing structure 10. The performance parameters of the electrode assembly 30, such as energy density, cycle life, and safety, directly determine the overall performance of the battery 100. It can be understood that the internal capacity of the casing structure 10 directly determines the maximum size that the electrode assembly 30 can be, thus affecting the energy density of the battery 100.

[0279] The battery 100 directly converts chemical energy into electrical energy to provide power through a reversible redox reaction between the active materials on the positive and negative electrodes and the electrolyte. It should be noted that the positive electrode is the electrode in the electrode assembly 30 that undergoes a reduction reaction during charging and discharging. The negative electrode is the electrode in the electrode assembly 30 that undergoes an oxidation reaction during charging and discharging. The separator is a structure in the electrode assembly 30 placed between the positive and negative electrodes to isolate the positive and negative electrodes and prevent short circuits. The separator is located between adjacent negative and positive electrodes to separate them. Exemplarily, the separator is a porous insulating film that allows lithium ions to pass through.

[0280] In some embodiments, the negative electrode, separator, and positive electrode are sequentially stacked and bonded to a mandrel by adhesive or hot-melt methods, and then wound to form the electrode assembly 30. In other embodiments, multiple negative electrode sheets, separators, and positive electrode sheets are stacked sequentially, and the resulting integral structure is then hot-pressed to form the electrode assembly 30. The electrode assembly 30 has gaps after formation, allowing electrolyte to enter the assembly. The electrolyte is used to wet the electrode assembly 30, ensuring that ions can move freely during charging and discharging.

[0281] The positive electrode includes a positive electrode body (e.g., aluminum foil), a positive active material layer (e.g., ternary material, lithium iron phosphate, or lithium cobalt oxide) coated on the surface of the positive electrode body, and positive electrode tabs. The negative electrode includes a negative electrode body (e.g., copper foil), a negative active material layer (e.g., carbon or silicon) coated on the surface of the negative electrode body, and negative electrode tabs. The positive and negative electrode bodies are structures used to collect and conduct the current generated by the active material layer during the electrochemical reaction, and to serve as a supporting framework for the active material layer. The positive and negative electrode tabs are structures used to conduct the current generated by the internal electrochemical reaction of the battery 100 to the external circuit. At this point, the battery 100 forms a circuit capable of supplying current, enabling the battery 100 to provide electrical energy.

[0282] Since the battery 100 in this application includes the housing structure 10 described in any of the above embodiments, it is understood that the battery 100 has at least the same beneficial effects as the housing structure 10. Therefore, the beneficial effects of the battery 100 should be referred to the beneficial effects of the housing structure 10 described above.

[0283] Please refer to Figures 1 to 3 In some embodiments, the electrode assembly 30 is spaced apart from the coiled portion 1333 in the height direction Z of the battery 100.

[0284] In the above embodiments, it can be understood that the height direction Z of the battery 100 is the same as the height direction Z of the housing structure 10. When the electrode assembly 30 and the coiling portion 1333 are spaced apart in the height direction Z and are opposite to each other, the electrode assembly 30 will not rub against the coiling portion 1333, thus preventing damage to the second functional layer 1359. This helps to ensure the integrity and reliability of the second functional layer 1359, thereby ensuring the protective effect of the second functional layer 1359 on the substrate layer 1355.

[0285] Please refer to Figure 1 , Figure 2 and Figure 4In some embodiments, the battery 100 further includes a busbar 50, which is electrically connected to the electrode assembly 30 and fixedly connected to the body portion 1331. In the height direction Z of the housing 13, the busbar 50 is spaced apart from the coiled portion 1333.

[0286] The busbar 50 is a key structural component inside the battery 100 used to collect and output current from the electrode assembly 30. The busbar 50 is typically a circular or irregularly shaped metal sheet, and its material can be, but is not limited to, at least one of aluminum, copper, or nickel. In the height Z direction of the housing 13, the busbar 50 is positioned between the electrode assembly 30 and the cover plate 11. Through its electrical connection with the electrode assembly 30, it physically collects the current generated by the electrode assembly 30 and guides it to the external circuit through structures such as terminals (located at the ends of the cover plate 11 or housing 13, not shown) or connecting pieces (not shown). The connection between the busbar 50 and the electrode assembly 30 is often achieved using ultrasonic welding or laser welding, ensuring low contact resistance and high current carrying capacity.

[0287] In this application, the busbar 50 is fixedly connected to the body portion 1331, thereby stably mounting the busbar 50 inside the housing structure 10. The connection between the busbar 50 and the body portion 1331 can be either detachable or non-detachable. When the busbar 50 and the coiling portion 1333 are spaced apart in the height direction Z and opposite to each other, the electrode assembly 30 will not rub against the busbar 50, thus preventing damage to the second functional layer 1359. This helps ensure the integrity and reliability of the second functional layer 1359, thereby guaranteeing the protective effect of the second functional layer 1359 on the substrate layer 1355.

[0288] Please refer to Figure 1 and Figure 11 Thirdly, this application provides a battery pack 1000. The battery pack 1000 includes the battery 100 described in any of the above embodiments.

[0289] Specifically, the battery pack 1000 is a composite structure composed of multiple individual batteries 100. The battery pack 1000 can store and release energy by connecting and controlling the batteries 100. The battery pack 1000 typically includes batteries 100 and a carrier. Multiple batteries 100 can be connected in series, parallel, or a combination thereof; a combination means that multiple batteries 100 are connected in both series and parallel. Multiple batteries 100 can be directly connected in series, parallel, or a combination thereof, and then the entire assembly of the multiple batteries 100 is housed within a carrier (e.g., a battery box). The battery pack 1000 may also include other structures; for example, the battery pack 1000 may also include a busbar (not shown) for electrical connection between the multiple batteries 100. It is understood that the number of batteries 100 in the battery pack 1000 can be adaptively adjusted according to the application scenario and capacity.

[0290] A battery box is a structure for holding a battery 100. The cross-section of the battery box may be, but is not limited to, circular, elliptical, square, or other polygonal shapes. The battery box is made of materials including, but not limited to, metals and non-metals. Metals include aluminum, iron, steel, aluminum alloys, or iron alloys, while non-metals include, but are not limited to, plastics. The battery box includes a body and a lid. The body and lid are combined to form a receiving cavity 1337, in which the battery 100 is housed. The body is the component in the battery box that loads and supports the battery 100. One end of the body is closed, and the other end has an opening for the battery 100 to be inserted into the receiving cavity 1337. The lid is the component in the battery box that covers the opening. The connection between the body and the lid can be detachable. Furthermore, when the battery box includes a body and a lid, the battery box may not be made of a single material. For example, the body and lid may be made of the same material, aluminum alloy. The battery box may also have different components made of different materials. For example, the body may be made of metal, while the lid may be made of plastic. Of course, the materials for the box body and the lid can also be combined with other materials, which will not be listed here.

[0291] Since the battery pack 1000 in this application includes the battery 100 described in any of the above embodiments, it is understood that the battery pack 1000 includes at least the same beneficial effects as the battery 100. Therefore, the beneficial effects of the battery pack 1000 should be referred to the beneficial effects of the battery 100 described above.

[0292] Please refer to Figure 1 , Figure 11 and Figure 12 Fourthly, this application provides an electrical appliance 10000. The electrical appliance 10000 includes the battery 100 described in any of the above embodiments; or, the battery pack 1000 described in any of the above embodiments.

[0293] Specifically, electrical equipment 10000 refers to a device or system that uses electrical energy to work or perform specific functions. The core function of electrical equipment 10000 is to convert electrical energy into other forms of energy (such as light energy, heat energy, and mechanical energy). Electrical equipment 10000 includes load devices that directly consume electrical energy (such as lighting fixtures and electric motors) as well as energy storage and power supply devices, such as battery 100 or battery pack 1000. Battery 100 or battery pack 1000 stores electrical energy through internal electrochemical reactions and releases it when needed to provide power support for electrical equipment 10000.

[0294] Electrical equipment 10000 can be, but is not limited to, vehicles, smart wearable devices, mobile terminals, home appliances, and medical devices; this application embodiment does not limit this. Vehicles include, but are not limited to, cars, buses, trains, ships, aircraft, etc. Smart wearable devices include, but are not limited to, smartwatches, smart bracelets, neck massagers, etc. Mobile terminals include, but are not limited to, smartphones, laptops, tablets, POS (point of sales terminal) machines. Home appliances include, but are not limited to, televisions, washing machines, air conditioners, rice cookers, smart robot vacuums, smart lights, etc. Medical devices include, but are not limited to, infrared electronic thermometers, pulse oximeters, body composition analyzers, etc. Correspondingly, the battery 100 or battery pack 1000 may have different shapes, sizes, capacities, and performance characteristics.

[0295] Since the electrical device 10000 in this application embodiment includes a battery 100 or a battery pack 1000, it is understood that the electrical device 10000 has at least the same beneficial effects as the battery 100 or the battery pack 1000. Therefore, the beneficial effects of the electrical device 10000 should be referred to the beneficial effects of the battery 100 or the battery pack 1000 described above.

[0296] The technical features of the embodiments described above can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as the combination of these technical features does not contradict each other, it should be considered within the scope of this specification. Furthermore, other implementation methods can be derived from the above embodiments, allowing for structural and logical substitutions and changes without departing from the scope of this disclosure.

[0297] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A casing structure (10) for a battery (100), characterized in that, comprising: a housing (13), wherein the housing (13) in the thickness direction comprises a base layer (1355) and a functional layer (1357) disposed on at least one side of the base layer (1355), and the electrical conductivity of the functional layer (1357) is less than the electrical conductivity of the base layer (1355).

2. The housing structure (10) according to claim 1, characterized in that, The resistivity of the functional layer (1357) at 20°C is ≤1×10⁻⁶. -6 Ω·m; and / or, The resistivity of the substrate layer (1355) at 20°C is ≤1×10⁻⁶. -7 Ω·m; and / or, the ratio k of the resistivity of the functional layer (1357) at 20°C to the resistivity of the base layer (1355) at 20°C satisfies: 1<k≤1000; and / or, the functional layer (1357) is at least one of a stainless steel layer, a zirconium layer, a titanium layer, a titanium alloy layer, a zinc layer, a copper layer, a copper alloy layer and a nickel alloy layer.

3. The shell structure (10) according to claim 1, characterized in that, The functional layer (1357) comprises: a first functional layer (1358), disposed on the outer surface of the base layer (1355); and, a second functional layer (1359), disposed on the inner surface of the base layer (1355), wherein the first functional layer (1358) and the second functional layer (1359) are made of the same first material, the base layer (1355) is made of a second material, and the electrical conductivity of the first material is less than the electrical conductivity of the second material.

4. The housing structure (10) according to claim 3, characterized in that, the first functional layer (1358) is at least one of a stainless steel layer, a zirconium layer, a titanium layer, a titanium alloy layer, a zinc layer, a copper layer, a copper alloy layer and a nickel alloy layer; and / or, the second functional layer (1359) is at least one of a stainless steel layer, a zirconium layer, a titanium layer, a titanium alloy layer, a zinc layer, a copper layer, a copper alloy layer and a nickel alloy layer; and / or, the base layer (1355) is at least one of a gold layer, a copper layer, a tungsten layer, an aluminum layer, a silver layer, a copper alloy layer, an aluminum alloy layer or a silver alloy layer.

5. The housing structure (10) according to claim 3, characterized in that, the thickness T1 of the first functional layer (1358) and the thickness T2 of the base layer (1355) satisfy: 0.04≤T1 / T2≤2; and / or, the thickness T3 of the second functional layer (1359) and the thickness T2 of the base layer (1355) satisfy: 0.04≤T3 / T2≤2; and / or, the thickness T3 of the second functional layer (1359) and the thickness T1 of the first functional layer (1358) satisfy: 0.2≤T3 / T1≤8; and / or, the thickness T1 of the first functional layer (1358) satisfies: 0.02mm≤T1≤0.10mm; and / or, the thickness T2 of the base layer (1355) satisfies: 0.05mm≤T2≤0.50mm; and / or, the thickness T3 of the second functional layer (1359) satisfies: 0.02mm≤T3≤0.10mm; and / or, the thickness T of the housing (13) satisfies: 0.1mm≤T≤0.6mm; and / or, The resistivity of the first functional layer (1358) at 20°C is ≤1×10⁻⁶. -7 Ω·m; and / or, The resistivity of the second functional layer (1359) at 20°C is ≤1×10⁻⁶. -7 Ω·m.

6. The housing structure (10) according to claim 5, characterized in that, The thickness T1 of the first functional layer (1358) and the thickness T2 of the substrate layer (1355) satisfy: 0.1 ≤ T1 / T2 ≤ 1; and / or, The thickness T3 of the second functional layer (1359) and the thickness T2 of the substrate layer (1355) satisfy: 0.1 ≤ T3 / T2 ≤ 1; and / or, The thickness T3 of the second functional layer (1359) and the thickness T1 of the first functional layer (1358) satisfy: 0.5 ≤ T3 / T1 ≤ 5; and / or, The thickness T1 of the first functional layer (1358) satisfies: 0.04mm ≤ T1 ≤ 0.06mm; and / or, The thickness T2 of the substrate layer (1355) satisfies: 0.20mm ≤ T2 ≤ 0.40mm; and / or, The thickness T3 of the second functional layer (1359) satisfies: 0.04mm ≤ T3 ≤ 0.06mm; and / or, The thickness T of the shell (13) satisfies: 0.2mm≤T≤0.4mm.

7. The shell structure (10) according to any one of claims 3-5, characterized in that, The housing (13) further includes a protective layer (138) in the thickness direction, which covers the functional layer (1357). Under the same corrosive environment, the corrosion resistance of the protective layer (138) is better than that of the functional layer (1357).

8. The shell structure (10) according to claim 7, characterized in that, The corrosion rate s of the protective layer (138) satisfies: s < 1.0 mm / year; and / or, The thickness T4 of the protective layer (138) satisfies: 0.0002mm≤T4≤0.50mm.

9. The shell structure (10) according to any one of claims 3-6, characterized in that, In the height direction of the housing (13), the housing (13) includes a body part (1331) and a coiled part (1333). The coiled part (1333) is connected to the body part (1331) and protrudes toward the center of the housing structure (10) relative to the body part (1331). The housing structure (10) also includes a cover plate (11) which is connected to the housing (13).

10. The shell structure (10) according to claim 9, characterized in that, The housing (13) includes a bottom wall (131) and a side wall (133). The cover plate (11) is disposed at the end of the side wall (133) away from the bottom wall (131). The rolled portion (1333) is bent and connected to the body portion (1331) to form a protrusion (1332). In the height direction, there is a first distance D1 between the outer surface of the cover plate (11) and the outer surface of the bottom wall (131), and a second distance D2 between the protrusion (1332) and the outer surface of the cover plate (11). The first distance D1 and the second distance D2 satisfy: D2 / D1≥2%; or, The cover plate (11) includes a first end cap (117) and a second end cap (118). The first end cap (117) and the second end cap (118) are disposed at opposite ends of the housing (13). In the height direction, there is a third distance D3 between the outer surface of the first end cap (117) and the outer surface of the second end cap (118). There is a fourth distance D4 between the protrusion (1332) and the outer surface of the first end cap (117). The third distance D3 and the fourth distance D4 satisfy: D4 / D3≥2%.

11. The shell structure (10) according to claim 9, characterized in that, The housing (13) further includes a crimping portion (1335), which is connected to the coiling portion (1333) and together forms a receiving cavity (1337). The crimping portion (1335) includes a first sub-part (13351) and a second sub-part (13353), with the opposite ends of the first sub-part (13351) connected to the coiling portion (1333) and the second sub-part (13353) respectively. The housing structure (10) further includes: A sealing ring (15) is at least partially housed within the receiving cavity (1337) and located between the cover plate (11) and the housing (13) to seal the gap between the cover plate (11) and the housing (13).

12. The shell structure (10) according to claim 11, characterized in that, In the housing (13), all areas corresponding to the body portion (1331), the coiling portion (1333), and the pressing portion (1335) include the first functional layer (1358), the base layer (1355), and the second functional layer (1359); or, In the housing (13), only the area corresponding to the coiled part (1333) includes the first functional layer (1358), the base layer (1355) and the second functional layer (1359).

13. The shell structure (10) according to claim 11, characterized in that, At least a portion of the cover plate (11) extends into the receiving cavity (1337) and is enveloped by the sealing ring (15); or, A constraint space is formed on the side wall (133) of the housing (13) or the cover plate (11), and the sealing ring (15) is housed within the constraint space, including a first side (1501) and a second side (1503) that are radially opposite, and a third side (1505) and a fourth side (1507) that are axially opposite. The peripheral wall of the constraint space is used to limit and abut against three of the first side (1501), the second side (1503), the third side (1505), and the fourth side (1507); the constraint space is formed on the side wall (133). When the cover plate (11) is connected to the housing (13), the cover plate (11) limits and abuts against the other side of the first side (1501), the second side (1503), the third side (1505) and the fourth side (1507); the constraint space is formed on the cover plate (11), and when the cover plate (11) is connected to the housing (13), the side wall (133) limits and abuts against the other side of the first side (1501), the second side (1503), the third side (1505) and the fourth side (1507).

14. The shell structure (10) according to claim 13, characterized in that, The cover plate (11) includes a cover plate body (111) and a limiting part (113) connected to each other. The constraint space includes a groove (1130) on the limiting part (113). The groove (1130) includes a groove bottom wall (11301) and a circumferential side wall (11303) connected to the groove bottom wall (11301). The sealing ring (15) is housed in the groove (1130). The circumferential side wall (11303) is used to limit and abut against the first side (1501) and the second side (1503) of the sealing ring (15). The groove bottom wall (11301) is used to limit and abut against one of the third side (1505) and the fourth side (1507). The side wall (133) is used to limit and abut against the other of the third side (1505) and the fourth side (1507).

15. The shell structure (10) according to claim 13, characterized in that, The constrained space is the receiving cavity (1337). The peripheral wall of the receiving cavity (1337) is used to limit and abut against the third side (1505) and the fourth side (1507). The pressing part (1335) is used to limit and abut against one of the first side (1501) and the second side (1503). The cover plate (11) includes a cover plate body (111) and a limiting part (113). The limiting part (113) extends from the cover plate body (111) and is used to limit and abut against the other side of the first side (1501) and the second side (1503).

16. A battery (100), characterized in that, include: The shell structure (10) according to any one of claims 1-15; and, The electrode assembly (30) is housed in the housing structure (10).

17. The battery (100) according to claim 16, characterized in that, In the height direction of the battery (100), the electrode assembly (30) is spaced apart from the coiled portion (1333) of the housing (13); or, The battery (100) also includes a busbar (50), which is electrically connected to the electrode assembly (30) and fixedly connected to the body part (1331) of the housing (13). In the height direction of the housing (13), the busbar (50) is spaced apart from the coiled part (1333) of the housing (13).

18. A battery pack (1000), characterized in that, include: The battery (100) according to claim 16 or 17.

19. An electrical appliance (10000), characterized in that, include: The battery (100) according to claim 16 or 17; or, The battery pack (1000) as claimed in claim 18.

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