Battery explosion-proof device, battery and electric equipment

Abstract

The invention relates to the technical field of batteries, in particular to a battery explosion-proof device, a battery and electric equipment. The battery explosion-proof device comprises a shell structure and at least one layer of explosion-proof membrane, the shell structure is provided with an anti-explosion hole; the explosion-proof membrane covers the explosion-proof hole; the explosion-proof membrane comprises a metal layer and a composite resin layer, and the composite resin layer is connected between the shell structure and the metal layer. According to the battery explosion-proof device, the metal layer and the shell structure are connected through the composite resin layer, so that the bonding strength of the explosion-proof membrane is improved, the electrolyte corrosion resistance of the explosion-proof membrane is enhanced, and the explosion-proof performance is improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery explosion-proof device, a battery, and electrical equipment. Background Art

[0002] With the widespread development of electric vehicles and energy storage devices, the use of lithium-ion batteries has gradually increased. The design requirements for these batteries must not only meet energy density and charge-discharge performance requirements, but also ensure safety under high-voltage conditions. To this end, explosion-proof devices are often installed in the battery casing to release pressure in a timely manner when the internal gas pressure exceeds the safety threshold, preventing the battery from exploding.

[0003] Currently, commonly used explosion-proof devices primarily create a sealed structure by laser-welding explosion-proof aluminum sheets onto the housing. While existing explosion-proof devices can achieve a certain degree of pressure relief, the welding method of connecting the aluminum sheets to the housing is costly, inefficient, and prone to leaks during welding, limiting safety. Summary of the Invention

[0004] The present application provides a battery explosion-proof device, a battery, and an electrical device, which are used to solve the problems of high manufacturing cost and limited safety caused by welding aluminum sheets and shells in the explosion-proof device of the prior art.

[0005] A first aspect of the present application provides a battery explosion-proof device, comprising:

[0006] The shell structure is equipped with explosion-proof holes;

[0007] At least one layer of explosion-proof membrane, the explosion-proof membrane is covered on the explosion-proof hole; the explosion-proof membrane includes a metal layer and a composite resin layer, and the composite resin layer is connected between the shell structure and the metal layer.

[0008] In a possible implementation, when the number of the explosion-proof membranes is at least two, the two layers of the explosion-proof membranes are respectively arranged on two opposite sides of the explosion-proof hole.

[0009] In one possible implementation, the composite resin layer includes a connecting layer and a core layer, at least a portion of the connecting layer is connected to the metal layer and the core layer, and the metal layer is connected to the shell structure through at least a portion of the connecting layer.

[0010] In one possible implementation, the connecting layer is a maleic anhydride-modified resin layer.

[0011] In one possible implementation, the maleic anhydride-modified resin layer is a maleic anhydride-modified polypropylene layer.

[0012] In one possible implementation, the core layer is a resin layer.

[0013] In one possible implementation, the core layer is a polypropylene layer.

[0014] In one possible implementation, the ratio of the thickness of the connecting layer to the thickness of the core layer is (2-6):1.

[0015] In a possible implementation, the number of the connecting layers is at least two, wherein one connecting layer is located between the core layer and the metal layer, and the other connecting layer is located between the core layer and the shell structure.

[0016] In one possible implementation, the thickness of the composite resin layer is 0.05-0.2 mm;

[0017] And / or the thickness of the metal layer is 0.05-0.3 mm.

[0018] In a possible implementation, a first passivation layer is provided on a surface of the metal layer facing the composite resin layer;

[0019] And / or a second passivation layer is provided on a surface of the shell structure opposite to the explosion-proof membrane, and an orthographic projection of the explosion-proof membrane on the shell structure at least partially overlaps with the second passivation layer.

[0020] In a possible implementation, the passivation process is performed by using chromate.

[0021] In a possible implementation, the chromate includes trivalent chromate or hexavalent chromate.

[0022] In a possible implementation, the passivation thickness of the passivation process is 10-50 nm;

[0023] And / or the chromium content after passivation of the passivation process is 10-15 mg / m 2 .

[0024] In a possible implementation, the passivation process uses one of zirconium-titanium salt, transition metal salt, rare earth metal salt or organic passivation for passivation.

[0025] In one possible implementation, the metal layer includes at least one of aluminum, nickel, magnesium, zinc, copper, and stainless steel.

[0026] In a possible implementation manner, the metal layer and the composite resin layer are composite-molded by hot-melt.

[0027] In one possible implementation, the fusion temperature of the hot melt composite molding is 180-220°C;

[0028] and / or the fusion pressure of the hot melt composite molding is 0.4-0.6 MPa;

[0029] And / or the fusion time of the hot melt composite molding is 2-4 seconds.

[0030] In one possible implementation, the composite resin layer and the shell structure are composite-molded by hot-melt.

[0031] In one possible implementation, the fusion temperature of the hot melt composite molding is 180-220°C;

[0032] and / or the fusion pressure of the hot melt composite molding is 0.4-0.6 MPa;

[0033] And / or the fusion time of the hot melt composite molding is 3-6 seconds.

[0034] In a possible implementation, a sink groove is formed on at least one side surface of the shell structure, the sink groove is connected to the explosion-proof hole, and the explosion-proof membrane is accommodated in the sink groove.

[0035] In a possible implementation, a surface of the explosion-proof membrane away from the explosion-proof hole is flush with an opening edge of the sink.

[0036] A second aspect of the present application provides a battery, comprising the battery explosion-proof device as described in any one of the above.

[0037] A third aspect of the present application provides an electrical device comprising a battery as described in any one of the above.

[0038] The implementation of the embodiments of the present application has the following beneficial effects:

[0039] In the battery explosion-proof device of this embodiment, by using a composite resin layer to connect the metal layer and the shell structure, not only the bonding strength of the explosion-proof membrane is improved, but also its ability to resist electrolyte corrosion is enhanced, thereby improving the explosion-proof performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] To more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0041] Figure 1 An exploded view of a battery explosion-proof device according to an embodiment of the present invention is shown;

[0042] Figure 2 Schematic diagram of the cross-sectional structure of a battery explosion-proof device according to an embodiment of the present invention is shown;

[0043] Reference numerals:

[0044] 10-battery explosion-proof device; 100-housing structure; 110-explosion-proof hole; 120-sink; 200-explosion-proof membrane; 210-metal layer; 211-first passivation layer; 220-composite resin layer; 221-connecting layer; 222-core layer. DETAILED DESCRIPTION

[0045] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0046] With the widespread development of electric vehicles and energy storage devices, the use of lithium-ion batteries has gradually increased. The design requirements for these batteries must not only meet energy density and charge-discharge performance requirements, but also ensure safety under high-voltage conditions. To this end, explosion-proof devices are often installed in the battery casing to release pressure in a timely manner when the internal gas pressure exceeds the safety threshold, preventing the battery from exploding.

[0047] Currently, commonly used explosion-proof devices primarily create a sealed structure by laser-welding explosion-proof aluminum sheets onto the housing. While existing explosion-proof devices can achieve a certain degree of pressure relief, the welding method of connecting the aluminum sheets to the housing is costly, inefficient, and prone to leaks during welding, limiting safety.

[0048] Based on this, see Figures 1 to 2 As shown, an embodiment of the present invention provides a battery explosion-proof device 10, which includes a shell structure 100 and an explosion-proof membrane 200; the shell structure 100 is provided with an explosion-proof hole 110; the number of the explosion-proof membrane 200 is at least one, and the explosion-proof membrane 200 is covered on the explosion-proof hole 110; the explosion-proof membrane 200 includes a metal layer 210 and a composite resin layer 220, and the composite resin layer 220 is connected between the shell structure 100 and the metal layer 210.

[0049] In the battery explosion-proof device 10 of this embodiment, by using a composite resin layer 220 to connect the metal layer 210 and the shell structure 100, not only the bonding strength of the explosion-proof membrane 200 is significantly improved, but also its ability to resist electrolyte corrosion is enhanced, thereby effectively improving the overall explosion-proof performance. The composite resin layer 220 can provide excellent adhesion, maintain good stability when subjected to internal and external pressures, and reduce structural weaknesses caused by thermal expansion or contraction. In addition, the use of the metal layer 210 provides structural support for the explosion-proof membrane 200, further ensuring its integrity under extreme conditions. Specifically, the battery explosion-proof device 10 includes a battery explosion-proof valve, which is usually connected to the battery shell to form a solid connection structure to ensure that internal pressure can be effectively released when necessary to avoid potential explosion risks.

[0050] Compared to the traditional laser welding method for connecting the explosion-proof aluminum sheet and the housing, this method, using a composite resin layer 220 for connection, offers significant advantages. First, the use of composite resin layer 220 enhances the bonding strength of metal layer 210. While welded connections may have weak welds, the use of composite resin layer 220 avoids potential quality issues that may arise during the welding process, such as coating defects and weld stress concentration, which are potential safety hazards. Second, because this connection method does not require welding, the reliability of the entire production process is improved, making it more adaptable and enabling consistent quality performance under varying production conditions.

[0051] Furthermore, the composite resin layer 220 exhibits superior corrosion resistance to most metal materials, particularly in battery environments where the corrosive nature of electrolytes is significant. By enhancing the explosion-proof membrane 200's resistance to electrolytes, the risk of failure due to corrosion can be significantly reduced, ensuring continued reliable battery operation.

[0052] Specifically, the design of the battery explosion-proof device 10 allows the explosion-proof hole 110 to be adjusted in shape according to actual needs, including but not limited to a variety of shapes such as circular holes and rectangular holes. This design flexibility enables the battery explosion-proof device 10 to be optimized for different battery casing structures to accommodate diverse application requirements. For example, for battery types requiring a larger gas release channel, a larger rectangular hole can be designed, while for smaller or lower-power batteries, a smaller circular hole can be used. This not only meets the safety requirements of different batteries, but also increases the design's applicability and flexibility, thereby enhancing the applicability of the entire product.

[0053] In one embodiment, when there are at least two explosion-proof membranes 200, the two explosion-proof membranes 200 are respectively disposed on opposite sides of the explosion-proof hole 110. This arrangement can further enhance the overall stability and safety performance of the battery explosion-proof device 10.

[0054] Specifically, the purpose of providing a multi-layer explosion-proof membrane 200 is to effectively disperse and withstand internal pressure. During the battery's charge and discharge process, the generation of internal gas can cause a sharp increase in gas pressure. A single-layer explosion-proof membrane alone may not be able to effectively handle this sudden pressure surge. However, the dual-layer explosion-proof membrane 200 evenly distributes pressure to both sides, preventing membrane failure or damage due to localized excessive pressure.

[0055] Furthermore, the provision of multiple explosion-proof membranes 200 provides increased redundancy. During battery use, if one explosion-proof membrane 200 degrades, becomes damaged, or fails due to physical or chemical factors, another membrane 200 can still provide protection, ensuring a certain level of battery safety in the event of high voltage, thereby effectively reducing the risk of battery explosion or leakage.

[0056] Specifically, the composite resin layer 220 includes a connection layer 221 and a core layer 222 . At least a portion of the connection layer 221 is connected to the metal layer 210 and the core layer 222 . The metal layer 210 is connected to the shell structure 100 through at least a portion of the connection layer 221 .

[0057] In this embodiment, the core layer 222 primarily provides the necessary structural strength for the composite resin layer 220, ensuring its stability under external pressure and impact. The connecting layer 221, on the other hand, serves to enhance the bond between the composite resin layer 220 and the metal layer 210, ensuring good sealing performance under the required operating conditions.

[0058] Specifically, the core layer 222 provides support within the composite resin layer 220, effectively dispersing the various mechanical stresses applied to the explosion-proof membrane 200 and enhancing the overall stability. Furthermore, the material selection for the core layer 222 can be optimized based on specific application requirements. For example, a resin with excellent heat resistance and chemical stability can be selected to withstand the high temperatures and corrosive media that may be present in the battery operating environment.

[0059] In some embodiments, the connecting layer 221 and the core layer 222 can be made of resins of different materials. The flexibility of this design choice combines the advantages of two different material properties, thereby achieving the purpose of improving adhesion and structural strength at the same time. The connecting layer 221 can use a highly adhesive resin to ensure good adhesion to the metal layer 210 and effectively prevent peeling caused by gas expansion or external vibration. The core layer 222 can use a reinforced resin that has the characteristics of both lightness and high strength. It can maintain the overall lightweight of the composite resin layer 220 while protecting it, further optimizing the energy density performance of the battery.

[0060] It should be noted that the connecting layer 221 can be stacked with the core layer 222 to achieve a tighter bond and better overall structural performance. In this structural design, the material properties of the connecting layer 221 and the performance of the core layer 222 complement each other, jointly improving the overall stability and stress dispersion capability of the composite resin layer 220.

[0061] Specifically, by stacking the connecting layer 221 on top of the core layer 222, better interface contact and bonding can be achieved, thereby enhancing the bonding strength between them. This bonding method helps to effectively disperse the pressure when the explosion-proof membrane 200 is subjected to external impact or pressure, reducing stress concentration at the joint surface, thereby improving the durability and safety of the structure.

[0062] In some embodiments, the connecting layer 221 can also be wrapped around the outside of the core layer 222. The main advantage of this design is that it provides additional protection, effectively enhancing the protective performance of the core layer 222 under extreme conditions (such as high temperature and chemical corrosion). The wrap-around design not only reduces the direct impact of the external environment on the core layer 222, but also improves the overall sealing stability of the explosion-proof membrane 200, effectively preventing the leakage of electrolyte or gas, and ensuring the safe and reliable operation of the battery system under various operating conditions.

[0063] In one embodiment, the connecting layer 221 is a maleic anhydride-modified resin layer. Maleic anhydride-modified resin, as the material for the connecting layer 221, possesses superior bonding properties and good chemical resistance, effectively enhancing the bond strength between the composite resin layer 220 and the metal layer 210. The chemical structure in the maleic anhydride-modified resin reacts with the surfaces of the metal layer 210 and the housing structure 100 to form strong chemical bonds, thereby achieving excellent bonding and reliability.

[0064] The advantage of the maleic anhydride-modified resin layer is that it maintains stable physical properties over a wide temperature range, for example, maintaining its bond strength in both high and low temperature environments. This characteristic is well-suited for use in battery explosion-proof devices 10, as batteries may experience rapid temperature fluctuations during actual use. Furthermore, the maleic anhydride-modified resin exhibits excellent resistance to electrolytes, reducing the effects of electrolyte corrosion on the connecting layer 221 and further enhancing the overall durability and safety of the composite resin layer 220.

[0065] In a preferred embodiment, the connecting layer 221 is a maleic anhydride-modified polypropylene layer. Polypropylene, a widely used thermoplastic, possesses excellent mechanical properties and chemical stability, making it particularly suitable for use in battery explosion-proof devices 10. Modification with maleic anhydride effectively improves the surface polarity of polypropylene, enhancing its adhesion to the metal layer 210.

[0066] The melting point of polypropylene can be selected between 140-150°C. Selecting a material within this melting point range ensures that it can withstand high temperatures during use without softening, meeting the battery's high-temperature operating requirements. Specifically, when polypropylene is designed to have a melting point between 140°C and 150°C, it can provide excellent thermal stability and peel strength without compromising material properties, effectively improving the overall performance of the composite resin layer 220.

[0067] In addition, the melt index of polypropylene can be selected within the range of 6-10g / 10min, indicating relatively good fluidity, which is very important for injection molding or extrusion molding during the preparation process. When producing the composite resin layer 220, good fluidity can improve the filling of the material in the mold and ensure the density and uniformity of the final product. It should be noted that if the melt index value is too low, it may cause flow difficulties during processing; while if the melt index value is too high, it may lead to a decrease in the strength and stiffness of the material. Therefore, in actual applications, the matching of melting point and melt index should be comprehensively considered to ensure that the material properties are optimally balanced.

[0068] Specifically, the core layer 222 is a resin layer. The use of the resin layer plays an important role in composite materials because it not only ensures the strength of the composite resin layer 220, but also significantly improves the bond strength between the connecting layer 221 and the core layer 222. This strength improvement can be achieved through the physical and chemical properties of the resin layer itself, as well as its good compatibility with the connecting layer 221.

[0069] The core layer 222 primarily functions as an intermediate layer, providing reinforcement and support. By selecting an appropriate resin material, such as epoxy resin, polyester resin, or maleic anhydride-modified resin, the overall mechanical strength and chemical stability of the composite resin layer 220 can be effectively improved. This is because the resin layer effectively disperses stress when subjected to external forces or environmental changes, reducing the occurrence of localized damage and thus extending the service life of the composite material.

[0070] Furthermore, the choice of resin layer can effectively improve the bond strength between the tie layer 221 and the core layer 222. The chemical structure of the resin interacts with the components of the tie layer 221 to form a strong interfacial bond. This bonding process relies to a certain extent on the surface energy and fluidity of the resin layer. A good match between the two can optimize the intermolecular forces between the bonding surfaces, thereby improving the overall bond quality.

[0071] In one embodiment, core layer 222 is a polypropylene layer. Polypropylene is a widely used thermoplastic with significant advantages in mechanical properties, chemical stability, and processability. Polypropylene has a melting point between 150°C and 165°C. Selecting a material within this range effectively ensures structural stability in high-temperature environments, making it suitable for demanding applications, such as battery explosion-proof devices or other high-temperature equipment.

[0072] Specifically, the melting point of the polypropylene in the core layer 222 can be selected to be between 150°C and 165°C. This not only meets most process requirements but also ensures that the material will not soften or deform prematurely when heated in actual applications. For example, in actual applications, the melting point of polypropylene can be selected to be 150°C, 155°C, 160°C, and 165°C, with the specific selection depending on the operating temperature of the equipment. This setting ensures that the material can maintain a high level of thermal stability during the production process, thereby ensuring the safety and reliability of the entire equipment. Conversely, if the melting point of polypropylene is lower than 150°C, the material may lose strength under high-temperature operation, affecting its service life.

[0073] The melt index (MIF) of polypropylene can be selected between 2 and 8 g / 10 min, reflecting its fluidity, a property particularly important for injection molding and extrusion processes. The specific MIF values, such as 2, 4, 6, or 8 g / 10 min, can be adjusted based on product design and production process requirements. A low MIF results in poor fluidity of polypropylene, potentially causing significant underfill in the mold and affecting molding quality. A high MIF can reduce the material's strength and stiffness, impairing product performance. Therefore, selecting an appropriate MIF ensures excellent mold filling during processing, improving the consistency and quality of the final product.

[0074] The use of the polypropylene layer as the core layer 222 not only provides good mechanical properties, but also forms an excellent bonding interface with the maleic anhydride modified polypropylene layer of the connecting layer 221. This good combination can significantly improve the tensile strength, impact resistance and heat resistance of the composite material, so that the composite material can perform well under various working conditions. The reasonable selection of the core layer 222 makes the overall composite structure more resilient and durable when facing mechanical pressure, temperature changes and chemical environments, thereby enhancing the service life and safety of the explosion-proof membrane 200. Specifically, the ratio of the thickness of the connecting layer 221 to the thickness of the core layer 222 is (2-6):1. The setting of this ratio has an important influence on the mechanical properties and processing properties of the material. The thickness of the connecting layer 221 needs to be greater than or equal to the core layer 222 to a certain extent to ensure that when the composite material is subjected to force, the connecting layer can effectively bear and disperse the externally applied pressure, thereby avoiding stress concentration and local damage of the material during use.

[0075] Within this ratio range, the thickness of the connecting layer 221 can be selected to be 2, 3, 4, 5, or 6 times the thickness of the core layer 222. For example, when the thickness of the core layer 222 is 0.01 mm, the thickness of the connecting layer 221 can be selected to be 0.02 mm, 0.03 mm, 0.04 mm, 0.05 mm, or 0.06 mm. This configuration has the advantage of providing the composite material with the required strength and stiffness under various working conditions, meeting the needs of different application scenarios.

[0076] Furthermore, setting the thickness ratio of the connecting layer 221 to the core layer 222 at (2-6):1 significantly improves the performance of the bonding interface. When the thickness of the connecting layer 221 is appropriately increased relative to the core layer 222, the intervening area of ​​the connecting layer increases, helping to improve the bond strength between it and the core layer 222, thereby enhancing the stability and durability of the entire composite structure. This design ensures that the composite material maintains excellent mechanical properties under changing operating conditions.

[0077] It's important to note that when the thickness ratio of the connecting layer 221 exceeds the recommended range (e.g., below 2:1 or above 6:1), material performance may be compromised. If the connecting layer 221 is too thin, it may not effectively resist external forces, reducing the impact resistance and fatigue life of the entire structure. On the other hand, an excessively thick connecting layer may increase the material's weight, affecting processing efficiency and leading to unnecessary cost. Therefore, in specific applications, the thickness ratio of the connecting layer 221 to the core layer 222 should be optimized based on actual design requirements to achieve the optimal balance between performance and cost.

[0078] In a preferred embodiment, there are at least two connecting layers 221, one of which is located between the core layer 222 and the metal layer 210, and the other is located between the core layer 222 and the shell structure 100. This design not only enhances the overall structural strength of the composite resin layer 220, but also improves the bonding strength between the composite resin layer 220 and the metal layer 210.

[0079] In this embodiment, the presence of first tie layer 221 forms a bonding interface between core layer 222 and metal layer 210. This bonding interface provides the composite material with excellent mechanical properties, maintaining a close connection between metal layer 210 and adjacent functional layers, effectively transferring external loads and preventing material fatigue or fracture due to stress concentration. Tie layer 221 also helps improve adhesion between the metal and plastic materials, thereby enhancing the durability of the overall structure.

[0080] The second connecting layer 221 is primarily responsible for connecting the core layer 222 to the shell structure 100. This structure effectively transfers external loads from the shell structure 100 to the core layer 222 via the connecting layer 221, allowing the explosion-proof membrane 200 to better withstand external shocks and pressures. The provision of this connecting layer 221 further enhances the impact resistance of the explosion-proof membrane 200, increasing safety, particularly by preventing material failure or deformation in the event of unexpected impacts or high loads.

[0081] The at least two connecting layers 221 more effectively provide multi-directional stress support for the explosion-proof membrane 200. The increased number of connecting layers 221 allows for optimized stress distribution and release within the composite material under varying operating conditions. Specifically, a properly designed connecting layer 221 effectively reduces stress concentration at the joint, thereby minimizing the risk of failure due to poor connections. The structural design and material properties of the different layers can further improve the overall material's stiffness and toughness.

[0082] It should be noted that the number of connecting layers 221 can be two, three, or more, and this is not a single limitation. In practice, it is preferred that the connecting layer 221 be connected to the external structure. This arrangement improves the mechanical properties and durability of the entire composite resin layer 220. By effectively integrating the connecting layer 221 into the overall layout, not only can the distribution of external loads be optimized, but the overall impact resistance of the composite resin layer 220 can also be enhanced.

[0083] Furthermore, a multi-layer core layer 222 can be provided within the composite resin layer 220, with a connecting layer 221 positioned between adjacent core layers 222. This design concept helps improve the overall strength of the composite resin layer 220. Specifically, the interaction of the multiple core layers 222 effectively disperses external loads applied to the material, while the connecting layer 221 enhances the adhesion between the layers. This multi-layer structure also significantly improves the rigidity and toughness of the composite resin layer 220, effectively preventing damage and deformation of the explosion-proof membrane 200 during impact or severe deformation, thereby ensuring the durability and safety of its functionality.

[0084] Specifically, the thickness of the composite resin layer 220 is 0.05-0.2mm; the key to selecting this thickness range is to ensure that the composite resin layer 220 achieves the goal of lightweighting while maintaining the necessary structural strength and rigidity. In the specific implementation process, the thickness of the composite resin layer 220 can be different values ​​such as 0.05mm, 0.1mm, 0.15mm or even 0.2mm. By flexibly adjusting the thickness of this layer, the processing performance of the material can be optimized, making it perform well in a variety of application environments. For example, when subjected to external pressure and impact, a moderate thickness can effectively disperse stress and prevent the material from being too thin and causing insufficient strength; if the thickness exceeds 0.2mm, it may add unnecessary weight and reduce the energy efficiency and flexibility of the material.

[0085] Specifically, the thickness of the metal layer 210 is 0.05-0.3mm, also to ensure that the material achieves a good balance between strength and stiffness. When the thickness of the metal layer 210 is less than 0.05mm, it may affect its impact resistance and deformation resistance; while exceeding 0.3mm will increase the overall weight, which is inconsistent with the trend of lightweight design. In specific implementations, the thickness of the metal layer 210 can be selected to be 0.05mm, 0.1mm, 0.2mm, 0.3mm, etc. to meet different application requirements. Selecting the appropriate thickness will significantly improve the enabling performance and safety of the material.

[0086] In a preferred embodiment, the composite resin layer 220 is constructed to include two connecting layers 221 and a core layer 222. The two connecting layers 221 are connected to opposite sides of the core layer 222, thereby forming a multi-layer composite structure. The thickness of the connecting layer 221, the thickness of the core layer 222, and the thickness of the connecting layer 221 are in a ratio of 1:(2-6):1. This ratio not only ensures the balance of the overall structure but also effectively improves the material's load-bearing capacity and impact resistance. By maintaining this ratio, optimal support is achieved between the connecting layer 221 and the core layer 222, resulting in the composite resin layer 220 having greater toughness and adaptability during use.

[0087] Furthermore, the design of two connecting layers 221 and one core layer 222 allows for flexible adjustment of material properties in different application scenarios. For example, in applications requiring increased bending and tensile strength, the thickness of the core layer 222 can be appropriately increased while the thickness of the connecting layer 221 remains unchanged, thereby achieving ideal structural optimization.

[0088] Furthermore, a first passivation layer 221 is provided on the side of the metal layer 210 facing the composite resin layer 220 to enhance the bonding strength between the metal layer 210 and the composite resin layer 220. Passivation is a process that forms a protective film on a metal surface through chemical or electrochemical methods. This treatment not only significantly improves the corrosion resistance of the metal material but also improves its surface roughness, thereby enhancing the bonding between the metal layer 210 and the subsequent composite resin layer 220.

[0089] Specifically, during the passivation process, the surface of the metal layer 210 undergoes pre-treatments such as cleaning and pickling, and is then treated with chemicals to form a first passivation layer 211. This first passivation layer 211 has a microscopically irregular surface structure, which provides more mechanical engagement and contact points, effectively increasing the contact area between the metal layer 210 and the composite resin layer 220. This feature enhances bonding strength while also improving the material's durability and impact resistance.

[0090] In addition, the thickness and composition of the first passivation layer 211 also have a significant impact on the passivation effect. Generally speaking, the thickness of the first passivation layer 211 can be selected between 10-50nm, and specific values ​​may include 1nm, 3nm, 5nm and 8nm, etc., which are adjusted according to design requirements. Within this range, the first passivation layer 211 of appropriate thickness can improve the corrosion resistance of the metal layer 210 without increasing the weight of the material. However, if the thickness of the first passivation layer 211 is too thin, it may not be able to effectively block the corrosive medium, resulting in insufficient bonding strength; while if it is too thick, it may affect the rigidity and other physical properties of the material. Therefore, the appropriate thickness of the first passivation layer 211 should be comprehensively considered during design to achieve the best bonding effect.

[0091] The first passivation layer 211 formed through this passivation process not only improves the corrosion resistance of the metal layer 210, but also provides a stronger bonding force between the composite resin layer 220 and the metal layer 210. In practical applications, this structural design can effectively improve the overall reliability of the material and reduce performance degradation caused by environmental changes during use.

[0092] Specifically, the passivation process utilizes chromate. Chromate passivation is an effective metal surface treatment method widely used to improve the corrosion resistance of various metal materials. This process involves contacting a chromate solution with the metal layer 210, causing a chemical reaction to form a first passivation layer 211 with excellent adhesion and corrosion resistance.

[0093] The specific implementation process of chromate passivation involves multiple steps. First, the surface of the metal layer 210 is pretreated, including cleaning and pickling, to remove oil, rust, and oxide layers, ensuring a clean metal surface and laying the foundation for subsequent passivation. After pretreatment, the metal layer 210 is immersed in a passivation solution containing chromate. During this process, the chromium ions in the chromate react with the metal surface, forming a dense chromate film. The formation of this film not only prevents direct contact between the metal and the external environment, but also significantly improves the bonding strength between the metal layer 210 and the composite resin layer 220.

[0094] The formed first passivation layer 211 is suitable for various metal substrates, including aluminum, galvanized steel, and stainless steel. Specifically, the metal materials may include aluminum alloys, galvanized steel sheets, and 304 or 316 stainless steel. During the chromate passivation process, in addition to providing corrosion protection, the microstructure and surface roughness of the first passivation layer 211 effectively increase the contact area between the metal layer 210 and the composite resin layer 220, enhancing bonding strength. Furthermore, the chromate passivation treatment improves the adhesion properties of the metal surface, further enhancing the overall structural strength of the composite material.

[0095] In one embodiment, the chromate includes trivalent chromate or hexavalent chromate. These two types of chromate each have their own unique chemical properties and applicable scenarios during the passivation process, thereby being able to meet the anti-corrosion requirements of different metal materials.

[0096] Specifically, trivalent chromate exhibits high stability, forming a more uniform and dense passivation film upon contact with metal surfaces. When trivalent chromium ions in the chromate solution react with the metal surface, a chromium compound film forms. This film effectively blocks the penetration of oxygen and moisture while also slowing the metal's oxidation reaction. This characteristic makes trivalent chromate particularly suitable for metals exposed to highly corrosive environments.

[0097] Hexavalent chromate, however, exhibits particular advantages in certain circumstances. Although the passivation film it forms is generally thin, it can provide a relatively rapid passivation reaction during the processing of certain high-quality alloys and specialized materials. Its rapid reaction speed significantly shortens the passivation process, making it suitable for rapid processing on production lines. Furthermore, hexavalent chromate passivation effectively reduces the coefficient of friction on metal surfaces, reducing wear and tear during subsequent processing or use, thereby increasing the metal's service life.

[0098] Specifically, the chromium content after passivation is 10-15 mg / m 2The chromium content range is determined based on the performance requirements and application environment of the passive film formed on the metal surface during the chromate passivation process. When the chromium content is 10-15mg / m2, a dense and uniform passive film can be effectively formed on the metal surface, thereby improving the metal's corrosion resistance and oxidation resistance.

[0099] It's worth noting that the lower limit of chromium content, 10 mg / m², is sufficient to provide basic protection for the metal substrate, while the upper limit, 15 mg / m², is crucial to ensuring the passivation film can withstand more demanding environments in actual use. Within this range, different chromium contents can be adjusted to meet specific application requirements. For example, when metal parts are exposed to extreme environments for long periods of time, a chromium content close to 15 mg / m² may be preferred to enhance corrosion and wear resistance. For relatively mild environments, a chromium content close to 10 mg / m² can effectively reduce costs while still maintaining good performance.

[0100] When selecting the chromium content, it's also important to consider potential technical disadvantages that may arise during processing. A chromium content below 10 mg / m² may result in an insufficient thickness of the passivation film, making it ineffective in preventing oxidation and wear of the metal substrate and increasing the risk of material failure during use. Conversely, a chromium content exceeding 15 mg / m² may enhance the protective properties of the passivation film, but the excessive presence of chromium in the material may lead to structural instability in the film.

[0101] In another embodiment, a chromium-free material may be selected for the passivation process, and the passivation process is performed using one of zirconium-titanium salts, transition metal salts, rare earth metal salts, or organic passivation.

[0102] Specifically, zirconium-titanium salts can form a stable and uniform passivation film during passivation treatment, thereby improving the corrosion resistance of metal surfaces. This type of passivation film typically exhibits excellent adhesion and hardness, making it suitable for applications requiring extreme environmental resistance, such as aerospace, automotive, and marine engineering. Furthermore, zirconium-titanium compounds possess strong high-temperature resistance and excellent chemical stability, enabling them to maintain their protective effects for extended periods in high-temperature and corrosive media.

[0103] Transition metal salts, such as yttrium oxide salts, nickel salts, and cobalt salts, also demonstrate excellent performance in the passivation process. These metal salts can form a transition metal compound film on the metal surface. This film not only provides protection from oxygen and moisture but also increases the lubricity of the metal surface, reducing wear and friction, and extending the service life of components. Therefore, in applications requiring improved anti-friction performance, transition metal salt passivation often plays a vital role.

[0104] Rare earth metal salts, such as cerium and lanthanum salts, possess superior passivation properties, promoting reactions on metal surfaces to form denser and more uniform protective films. These films effectively inhibit metal corrosion, and in some specialized environments, the addition of rare earth metals may improve the material's electrical conductivity, thus playing a valuable role in electronics and other high-tech fields.

[0105] Organic passivation, such as water-based acrylic resins, is low-pollution and environmentally friendly. The relatively gentle process reduces physical and chemical damage to the metal surface, resulting in a film with excellent flexibility and UV resistance. Furthermore, in some cases, organic passivation films can enhance the aesthetics of metal surfaces, making products more competitive in terms of appearance.

[0106] The selection and implementation of chromium-free passivation materials can be tailored to the specific application requirements. For example, the concentration of zirconium-titanium salts during treatment can be flexibly adjusted within an appropriate range to achieve optimal passivation. Furthermore, the recommended operating temperature, duration, and post-treatment methods often vary depending on the characteristics of different chromium-free passivating agents. Therefore, when selecting a passivating agent other than chromium, various factors must be considered, including cost, process safety, and the specific requirements of the application, to ensure that the resulting passivation film meets the desired performance standards.

[0107] Furthermore, the surface of the housing structure 100 opposite the explosion-proof membrane 200 is passivated to form a second passivation layer. The orthographic projection of the explosion-proof membrane 200 on the housing structure 100 at least partially overlaps with the second passivation layer, thereby enhancing the bond strength between the explosion-proof membrane 200 and the housing structure 100. In this embodiment, the orthographic projection of the explosion-proof membrane 200 on the housing structure 100 at least partially overlaps with the second passivation layer, allowing the second passivation layer to contact the explosion-proof membrane 200. This design effectively improves the adhesion between the explosion-proof membrane 200 and the housing structure 100, thereby avoiding potential drawbacks of traditional connection methods while enhancing the overall performance and stability of the product.

[0108] Passivation significantly improves the electrolyte resistance of the housing structure 100. This is due to the surface properties of the formed passivation film, which provides more effective protection for the metal substrate of the housing structure 100 when it comes into contact with the electrolyte in the environment. Furthermore, the passivation film exhibits excellent chemical stability and physical durability, maintaining its protective properties in various harsh operating environments and preventing metal oxidation and degradation, thereby extending the service life and reliability of the housing structure 100.

[0109] Specifically, the passivation thickness of the passivation process is 10-50nm. The passivation thickness in this range can be reasonably adjusted according to the specific application requirements. For example, a passivation thickness of 10nm can be selected to achieve the purpose of lightweighting, and when it is necessary to enhance corrosion resistance, the passivation thickness can be selected at 50nm to provide a stronger protective effect. At the same time, it is worth noting that if the passivation thickness is lower than 10nm, the effectiveness of the passivation film may be insufficient and unable to provide the required protection; and a passivation thickness higher than 50nm, although it can enhance certain performance, may increase costs and affect the overall design and lightweight requirements. When actually selecting, a reasonable value should be selected based on the specific application and expected performance of the product.

[0110] Specifically, the passivation process uses chromate, a common passivation method that forms a protective film on the metal surface, significantly improving the metal's corrosion resistance. Chromate, as a passivating agent, reacts with the metal surface to form a chromium-containing compound film. This dense and stable film effectively blocks the erosion of corrosive media and protects the metal substrate from corrosion damage.

[0111] In one embodiment, the chromate includes trivalent chromate or hexavalent chromate. These two chromates exhibit different properties during the passivation process. Trivalent chromate is relatively more environmentally friendly and helps improve the uniformity and adhesion of the passivation film during formation. Hexavalent chromate, on the other hand, generally offers a stronger corrosion protection effect, forming a protective film of moderate thickness in a relatively short time, significantly improving the protective properties of the metal. The appropriate chromate type should be selected based on actual application requirements to ensure optimal passivation processing results.

[0112] The chromium content after passivation processing is 10-15mg / m2. It should be noted that the chromium content should be controlled within the range of 10mg / m2 to 15mg / m2 to ensure the effectiveness and performance of the passivation film. Specifically, when the chromium content is set at 10mg / m2, the passivation film can provide basic corrosion protection and is suitable for applications with low environmental requirements. As the chromium content approaches 15mg / m2, the protective ability of the passivation film is significantly enhanced, and the durability is improved, making it suitable for applications with heavy loads or harsh working conditions.

[0113] Correspondingly, when the chromium content is less than 10mg / m2, the protective performance of the passivation film may be insufficient, thereby accelerating the corrosion of the metal base material, especially in humid or chemically corrosive environments. At the same time, if the chromium content is higher than 15mg / m2, although the protective performance of the passivation film may be enhanced, in some specific applications, when there are high requirements for film uniformity and stability, excessive chromium may lead to uneven distribution of the film layer, thereby creating a certain risk of failure.

[0114] Specifically, the metal layer 210 includes at least one of aluminum, nickel, magnesium, zinc, copper, and stainless steel. These metal materials each have excellent mechanical properties and corrosion resistance when used in the explosion-proof membrane 200, effectively improving the strength and durability of the explosion-proof membrane 200.

[0115] As a lightweight metal, aluminum has good strength and toughness. Its use in explosion-proof membranes can effectively reduce the weight of the overall structure. At the same time, since the aluminum oxide layer formed by aluminum has excellent passivation properties, it can enhance the corrosion resistance of the explosion-proof membrane, thereby increasing its service life in harsh environments.

[0116] Nickel, due to its high-temperature strength and excellent corrosion resistance, excels in applications requiring high strength. Nickel not only increases the alloy's tensile strength, but also forms a passivation film that effectively protects the metal substrate from environmental intrusion, thereby enhancing the reliability and safety of the explosion-proof membrane 200.

[0117] Magnesium, another lightweight metal, offers excellent specific strength, making its use in explosion-proof membranes a valuable tool for enhancing overall rigidity without increasing component weight. Magnesium's ease of processing and shaping allows for a variety of manufacturing processes to flexibly meet specific design requirements.

[0118] Zinc is a common anti-corrosion material, often used in surface coatings to prevent corrosion of substrates. Therefore, when zinc is included in the metal layer 210, it can effectively enhance the corrosion resistance of the explosion-proof membrane 200 and ensure its stability in wet or corrosive environments.

[0119] Copper is known for its excellent electrical conductivity and corrosion resistance, making it a popular choice in electronics and electrical applications. Its antioxidant properties and passivation properties support the Explosion-Proof Membrane 200's performance in electrical insulation and reducing the risk of electrostatic discharge.

[0120] Stainless steel, due to its unique alloy composition, offers excellent wear resistance, corrosion resistance, and oxidation resistance, making it suitable for a variety of industrial and everyday environments. Its strength and toughness ensure the stability of the explosion-proof membrane 200 when subjected to external impacts, making it safer and more reliable in use.

[0121] By rationally combining metal materials such as aluminum, nickel, magnesium, zinc, copper, and stainless steel, the advantages of each component are fully utilized to enhance the strength of explosion-proof membrane 200, while also achieving material economy and practicality in practical applications. This diverse metal layer design provides explosion-proof membrane 200 with a more robust structure and reliable protection, meeting the needs of various application scenarios.

[0122] In one embodiment, the metal layer 210 and the composite resin layer 220 are formed by hot-melt composite molding. This process effectively combines the advantages of both materials, thereby achieving higher overall performance. The hot-melt composite molding process involves bonding the metal layer 210 and the composite resin layer 220 under specific temperature, pressure, and time conditions. This process ensures close adhesion between the materials and forms a stronger bond interface under the action of heat and pressure.

[0123] Specifically, the fusion temperature of hot-melt composite molding is 180-220°C. Within this temperature range, the composite resin can be fully melted, and the physical properties of the metal layer remain stable. It should be noted that the fusion temperature can be 180°C, 190°C, 200°C, 210°C, or 220°C, which is determined according to actual design requirements and is not a sole limitation here. If the temperature is lower than 180°C, the composite resin layer 220 may not be completely melted, thereby reducing the bonding strength of the composite resin layer 220; and if the temperature exceeds 220°C, the metal layer 210 may be deformed or the resin may decompose, affecting the bonding strength.

[0124] In addition, the fusion pressure of hot-melt composite molding is set to 0.4-0.6MPa. This pressure range ensures that the materials can fully contact and form an effective bond during the composite process. Specifically, the fusion pressure can be 0.4MPa, 0.5MPa, or 0.6MPa, and can be flexibly selected in different application scenarios. Within this range, the overall strength and toughness of the explosion-proof membrane 200 are effectively improved. If the pressure is less than 0.4MPa, it may cause the gap in the bonding part to increase, while exceeding 0.6MPa may cause damage or deformation of the material.

[0125] The fusion time for hot-melt composite molding is set at 2-4 seconds to ensure sufficient time for the explosion-proof film 200 to form a good bond under the action of heat and pressure. The specific time can be 2 seconds, 3 seconds, or 4 seconds, and can be adjusted appropriately based on the thickness of the explosion-proof film 200 and the application requirements. If the time is set below 2 seconds, the composite resin layer 220 may not fully wet the metal layer 210, affecting the bonding effect. If it exceeds 4 seconds, the excessive cooling time may make it difficult to demold the finished product, thereby increasing production costs.

[0126] By controlling the temperature, pressure and time of hot-melt composite molding, efficient bonding between the metal layer 210 and the composite resin layer 220 can be achieved, thereby improving the overall strength and durability of the explosion-proof membrane 200.

[0127] In one embodiment, the composite resin layer 220 and the housing structure 100 are formed by hot-melt composite molding. The advantage of this process is that it can effectively achieve a close bond between the materials, thereby improving the performance and reliability of the battery explosion-proof device 10.

[0128] The fusion temperature range for hot-melt composite molding is set to 180-220°C. Specifically, the fusion temperature can be 180°C, 190°C, 200°C, 210°C, or 220°C. Processing within this range can ensure that the composite resin layer 220 is fully melted while also properly protecting the material properties of the shell structure 100. If the temperature is lower than 180°C, the composite resin layer 220 may not be fully melted, thereby affecting the bonding effect; temperatures higher than 220°C may cause the composite resin layer 220 to decompose or the shell structure 100 to deform, both of which will adversely affect the quality of the battery explosion-proof device 10. Therefore, selecting an appropriate temperature range is an important factor in optimizing the process effect.

[0129] The fusion pressure is set to 0.4-0.6MPa. Specifically, the pressure can be 0.4MPa, 0.5MPa or 0.6MPa. Such a pressure range can not only promote good contact between the composite resin layer 220 and the shell structure 100 and form an effective bonding interface, but also prevent material damage caused by excessive pressure. When the pressure is lower than 0.4MPa, gaps may exist on the bonding surface, thereby affecting the overall performance of the battery explosion-proof device 10; exceeding 0.6MPa may cause damage or deformation of the material. Therefore, controlling the appropriate pressure level is the key to ensuring the composite effect and product strength.

[0130] The fusion time for hot-melt composite molding is set to 3-6 seconds, where the fusion time can be 3 seconds, 4 seconds, 5 seconds, or 6 seconds. This time range ensures that the materials can effectively form a good bond under the dual effects of heat and pressure. If the fusion time is less than 3 seconds, the composite resin layer 220 may not fully wet the shell structure 100, affecting the bonding effect. If the fusion time is too long, exceeding 6 seconds, it may cause the molding temperature to be too low or the temperature to drop too quickly, thereby increasing the risk of difficulty in demolding the material.

[0131] In one embodiment, a recessed groove 120 is formed on at least one side of the housing structure 100. The recessed groove 120 is connected to the explosion-proof hole 110, and the explosion-proof membrane 200 is accommodated in the recessed groove 120. This design not only provides for the installation and positioning of the explosion-proof membrane 200, but also plays a crucial role in explosion-proof performance.

[0132] The shape and structure of the sink 120, a mounting structure, are designed to ensure the stability and robustness of the explosion-proof membrane 200. Since the membrane 200 is housed within the sink 120, the contact area between the membrane 200 and the housing structure 100 is increased, significantly enhancing the bond strength between the two. This enhanced bond effectively resists external impact and pressure, ensuring that the membrane 200 maintains its performance even under extreme operating conditions and reducing the risk of membrane failure.

[0133] In one embodiment, the diameter of the explosion-proof hole 110 can be designed to be 5 mm, and the explosion-proof hole 110 and the sink 120 are coaxially arranged to ensure the balance and symmetry of the two during the installation process. The sink 120 can be designed as a circular groove with a diameter set to 15 mm and a depth range of 0.1-0.3 mm. Specifically, the depth of the sink 120 can be selected to be 0.1 mm, 0.2 mm or 0.3 mm, and the specific value will be adjusted according to the material properties and the requirements of the actual use environment. When the depth is less than 0.1 mm, the explosion-proof membrane 200 may not be effectively accommodated, resulting in the membrane being unreliable; and a depth exceeding 0.3 mm may increase the difficulty of material processing, resulting in unnecessary waste and increased costs.

[0134] This design not only provides a stable mounting platform for the explosion-proof membrane 200, but also effectively reduces the risk of membrane displacement and dislodging due to external forces, thereby enhancing the safety and reliability of the overall structure. The coaxial arrangement of the explosion-proof hole 110 and the sink 120 ensures the symmetry of the combined structure, helps evenly distribute stress, and further enhances the durability of the structure. Furthermore, the design of the housing for the explosion-proof membrane 200 allows for flexible response to pressure fluctuations and impacts in various environments, ensuring its full protection in explosion-proof applications.

[0135] In a preferred embodiment, the surface of the explosion-proof membrane 200 away from the explosion-proof hole 110 is flush with the opening edge of the sink 120. This design is intended to ensure that the outer surface of the battery explosion-proof device 10 remains flush, thereby providing a smoother appearance overall and increasing safety during use.

[0136] Specifically, by maintaining the surface of the explosion-proof membrane 200 at the same height as the opening edge of the sink 120, the explosion-proof membrane 200 can be effectively prevented from protruding. This design not only makes the connection between the explosion-proof membrane 200 and the housing structure 100 tighter, but also reduces the risk of damage to the membrane body due to external impact or friction during daily use.

[0137] It's worth noting that if the surface of the explosion-proof membrane 200 is higher than the opening edge of the sink 120, it may cause the membrane to protrude during use, increasing the probability of collision with other objects. This unevenness may affect its effectiveness in explosion-proof applications and may even cause the membrane to tear or fall off, thereby reducing its explosion-proof performance.

[0138] The present invention is described in detail by way of examples, which include but are not limited to the following examples.

[0139] Example 1

[0140] The shell structure 100 may be an aluminum shell, and the metal layer 210 may be an aluminum layer with a thickness of 0.1 mm, 8021 system, and a diameter of 14.9 mm. The circular sink 120 has a diameter of 15 mm and a depth of 0.125 mm.

[0141] The explosion-proof hole 110 and the metal layer 210 are both subjected to chromate passivation treatment, and the treatment process is as follows:

[0142] First, the materials are treated with alkali solution, washed with water, and dried in sequence;

[0143] Then apply chromate passivation solution and bake at 120℃ for 1min. The chromium content after passivation is 12mg / m 2 , the passivation layer thickness is 20nm.

[0144] The specific structure of the explosion-proof film 200 is a metal layer 210, a first passivation layer 211 of the metal layer 210, and a composite resin layer 220. The metal layer 210 and the composite resin layer 220 are composited by hot-melt bonding at a temperature of 200°C, a pressure of 0.5 MPa, and a time of 2 seconds.

[0145] The explosion-proof membrane 200 has a diameter of 14.9 mm and a thickness of 0.15 mm. The total thickness of the composite resin layer 220 is 0.050 mm. The thickness ratio of the first connecting layer 221, the core layer 222, and the second connecting layer 221 is 1:3:1. The connecting layer 221 is maleic anhydride-modified polypropylene with a melting point of 145°C and a melt index of 8 g / 10 min. The core layer 222 is pure polypropylene with a melting point of 165°C and a melt index of 6 g / 10 min.

[0146] The explosion-proof membrane 200 is connected to the metal layer 210 through the first connecting layer 221 and to the shell structure 100 through the second connecting layer 221. The explosion-proof membrane 200 and the battery explosion-proof device 10 are hot-melt-fused at a temperature of 210°C, a pressure of 0.5 MPa, and a time of 4 seconds. The outer side of the explosion-proof membrane 200 is flush with the outer surface of the shell structure 100.

[0147] Example 2

[0148] In this embodiment, the thickness of the metal layer 210 is 0.11 mm, and the thickness ratio of the first connecting layer 221, the core layer 222, and the second connecting layer 221 is 1:1:1; the hot-melt time between the metal layer 210 and the composite resin layer 220 is 3 seconds; the hot-melt time between the explosion-proof membrane 200 and the battery explosion-proof device 10 is 5 seconds. Other conditions remain unchanged from Example 1.

[0149] Example 3

[0150] In this embodiment, the explosion-proof hole 110 and the metal layer 210 are both passivated with a chromium-free passivation solution, and the cerium content after passivation is 12 mg / m 2The thickness of the metal layer 210 is 0.11 mm, the total thickness of the composite resin layer 220 is 0.040 mm, and the thickness ratio of the first connecting layer 221, the core layer 222, and the second connecting layer 221 is 1:1:1; the hot-melt time between the metal layer 210 and the composite resin layer 220 is 3 seconds; the hot-melt time between the explosion-proof membrane 200 and the battery explosion-proof device 10 is 5 seconds. Other conditions remain unchanged from Example 1.

[0151] Comparative Example 1

[0152] In comparative example 1, a T-shaped groove of a certain depth and shape is punched on the cover plate, a pressure relief hole is punched in the groove, the aluminum-plastic film and the cover plate are fitted together to achieve sealing, and the outside of the groove needs to be covered with a PET film.

[0153] Comparative Example 2

[0154] In Comparative Example 2, the composite resin layer 220 is replaced by a maleic anhydride-modified polypropylene layer with a thickness of 50 μm, the surface of the metal layer 210 is not passivated, and other conditions remain unchanged from Example 1.

[0155] Detonation strength test method:

[0156] After the battery explosion-proof device 10 is assembled (the cover plate and the diaphragm are connected by welding in the comparative example), the interior of the shell structure 100 is inflated through the injection hole until the battery explosion-proof device 10 ruptures, and the air pressure value at this time is recorded.

[0157] Electrolyte corrosion test method:

[0158] After the battery explosion-proof device 10 is assembled, 1 / 3 of the electrolyte is injected into the shell structure 100 through the injection hole, and then the injection hole is sealed. The shell structure 100 is inverted with the explosion-proof hole 110 facing downward and stored at 60°C to observe the leakage time.

[0159]

[0160] It should be noted that X / YPCS means that the total number of batteries participating in the test is Y, and the number of batteries that show corrosion is X.

[0161] It can be seen from the comparison of Examples 1-3 with Comparative Example 1 that, compared with the explosion-proof solution of combining the aluminum-plastic film and the cover plate by welding, the detonation strength of the battery explosion-proof device 10 in this embodiment is effectively improved.

[0162] Comparison with Comparative Example 2 shows that when the aluminum sheet surface is not passivated, the electrolyte resistance between the metal layer and the polypropylene layer in the explosion-proof membrane is short, resulting in poor performance. This result demonstrates the importance of surface treatment of the aluminum sheet in improving the overall performance of explosion-proof membranes. Unpassivated aluminum sheet surfaces readily react with the electrolyte, leading to corrosion or degradation of the metal layer, thus compromising the structural integrity and durability of the explosion-proof membrane. This phenomenon further emphasizes the necessity of passivation treatment in the manufacture of explosion-proof membranes, which can significantly prolong the bond strength and electrolyte resistance between the aluminum sheet and the polypropylene layer.

[0163] The present invention further provides a battery, which includes the battery explosion-proof device 10 in any of the above embodiments. The shell structure 100 can be connected to the shell of the battery, or can be a partial structure of the shell.

[0164] In the battery explosion-proof device 10 of this embodiment, a composite resin layer 220 is used to connect the metal layer 210 and the shell structure 100. This design choice demonstrates its superiority in many aspects. First, the application of the composite resin layer 220 significantly improves the bonding strength between the explosion-proof membrane 200 and the shell structure 100. This increase in bonding strength can effectively enhance the stability of the explosion-proof membrane during the force-bearing process, thereby reducing the risk of failure of the explosion-proof membrane when subjected to external force. Secondly, the introduction of the composite resin layer 220 also enhances the battery explosion-proof device 10's resistance to electrolyte corrosion. Taking into account the common electrolytes in the battery working environment and their corrosiveness to various materials, the selection of the composite resin layer 220 can significantly extend the service life of the explosion-proof device, thereby improving the overall reliability of the battery.

[0165] The present invention further provides an electrical device, comprising the battery in any one of the above embodiments, wherein the battery is used to supply power to an electrical device in the electrical device.

[0166] In the electrical equipment of this embodiment, the use of a battery from any of the above-described embodiments can effectively enhance the explosion-proof performance of the electrical equipment. The explosion-proof device 10 of this embodiment utilizes a composite material structure, and the composite resin layer 220 connects the metal layer 210 and the housing structure 100 to achieve excellent bonding strength. Furthermore, the use of the composite resin layer significantly enhances the battery's corrosion resistance in electrolyte environments, thereby preventing the risk of fire or explosion under extreme conditions.

[0167] By improving the explosion-proof performance of batteries, the reliability and safety of the entire electrical equipment can be enhanced. First, batteries with a highly efficient explosion-proof design can effectively reduce safety hazards caused by abnormal conditions such as short circuits and overcharging, making the electrical equipment safer during operation, extending its service life, and reducing equipment damage caused by battery failure, thereby reducing maintenance costs. Specifically, the electrical equipment can be an electric vehicle.

[0168] In the description of the embodiments of the present application, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the embodiments of the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0169] In the description of the embodiments of this application, it should be noted that, unless otherwise specified or limited, the terms "connected" and "connection" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium. Those skilled in the art will understand the specific meanings of the above terms in the embodiments of this application based on the specific circumstances.

[0170] In the embodiments of the present application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, a first feature being "above," "above," and "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0171] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiments of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples, unless they are contradictory.

[0172] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A battery explosion-proof device (10), characterized in that: include: The shell structure (100) is provided with an explosion-proof hole (110); At least one explosion-proof membrane (200) is provided, wherein the explosion-proof membrane (200) is covered on the explosion-proof hole (110); the explosion-proof membrane (200) comprises a metal layer (210) and a composite resin layer (220), and the composite resin layer (220) is connected between the shell structure (100) and the metal layer (210).

2. The battery explosion-proof device (10) according to claim 1, characterized in that: When the number of the explosion-proof membranes (200) is at least two, the two layers of the explosion-proof membranes (200) are respectively arranged on opposite sides of the explosion-proof hole (110).

3. The battery explosion-proof device (10) according to claim 1, characterized in that: The composite resin layer (220) comprises a connecting layer (221) and a core layer (222), at least a portion of the connecting layer (221) is connected to the metal layer (210) and the core layer (222), and the metal layer (210) is connected to the shell structure (100) through at least a portion of the connecting layer (221).

4. The battery explosion-proof device (10) according to claim 3, characterized in that: The connecting layer (221) is a maleic anhydride modified resin layer.

5. The battery explosion-proof device (10) according to claim 4, characterized in that: The maleic anhydride modified resin layer is a maleic anhydride modified polypropylene layer.

6. The battery explosion-proof device (10) according to claim 3, characterized in that: The core layer (222) is a resin layer.

7. The battery explosion-proof device (10) according to claim 6, characterized in that: The core layer (222) is a polypropylene layer.

8. The battery explosion-proof device (10) according to claim 3, characterized in that: The ratio of the thickness of the connecting layer (221) to the thickness of the core layer (222) is (2-6):

1.

9. The battery explosion-proof device (10) according to any one of claims 2 to 8, characterized in that: The number of the connecting layers (221) is at least two, wherein one connecting layer (221) is located between the core layer (222) and the metal layer (210), and the other connecting layer (221) is located between the core layer (222) and the shell structure (100).

10. The battery explosion-proof device (10) according to claim 1, characterized in that: The thickness of the composite resin layer (220) is 0.05-0.2 mm; And / or the thickness of the metal layer (210) is 0.05-0.3 mm.

11. The battery explosion-proof device (10) according to claim 1, characterized in that: A first passivation layer (211) is provided on a surface of the metal layer (210) facing the composite resin layer (220); And / or a second passivation layer is provided on a surface of the shell structure (100) opposite to the explosion-proof membrane (200), and an orthographic projection of the explosion-proof membrane (200) on the shell structure (100) at least partially overlaps with the second passivation layer.

12. The battery explosion-proof device (10) according to claim 11, characterized in that: The first passivation layer (221) and / or the second passivation layer are passivated using chromate.

13. The battery explosion-proof device (10) according to claim 12, characterized in that: The chromate includes trivalent chromate or hexavalent chromate.

14. The battery explosion-proof device (10) according to claim 12, characterized in that: The passivation thickness of the passivation process is 10-50nm; And / or the chromium content after passivation of the passivation process is 10-15 mg / m 2 .

15. The battery explosion-proof device (10) according to claim 11, characterized in that: The passivation process adopts one of zirconium-titanium salt, transition metal salt, rare earth metal salt or organic passivation for passivation.

16. The battery explosion-proof device (10) according to claim 1, characterized in that: The metal layer (210) includes at least one of aluminum, nickel, magnesium, zinc, copper, and stainless steel.

17. The battery explosion-proof device (10) according to claim 1, characterized in that: The metal layer (210) and the composite resin layer (220) are composite-molded by hot-melt.

18. The battery explosion-proof device (10) according to claim 17, characterized in that: The fusion temperature of the hot melt composite molding is 180-220°C; and / or the fusion pressure of the hot melt composite molding is 0.4-0.6 MPa; And / or the fusion time of the hot melt composite molding is 2-4 seconds.

19. The battery explosion-proof device (10) according to claim 1, characterized in that: The composite resin layer (220) and the shell structure (100) are composite-molded by hot-melt.

20. The battery explosion-proof device (10) according to claim 19, characterized in that: The fusion temperature of the hot melt composite molding is 180-220°C; and / or the fusion pressure of the hot melt composite molding is 0.4-0.6 MPa; And / or the fusion time of the hot melt composite molding is 3-6 seconds.

21. The battery explosion-proof device (10) according to claim 1, characterized in that: A sink (120) is provided on at least one side surface of the shell structure (100), the sink (120) is connected to the explosion-proof hole (110), and the explosion-proof membrane (200) is accommodated in the sink (120).

22. The battery explosion-proof device (10) according to claim 21, characterized in that: A surface of one side of the explosion-proof membrane (200) away from the explosion-proof hole (110) is flush with an opening edge of the sink (120).

23. A battery, characterized in that: The invention comprises a battery explosion-proof device (10) as described in any one of claims 1 to 22.

24. An electrical device, characterized in that: Comprising the battery of claim 23.

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