Lithium battery with metal shell structure and preparation method thereof

Abstract

The invention discloses a lithium battery with a metal shell structure, which comprises a battery shell, the battery shell comprises a metal lower cover and a metal upper cover, the metal lower cover is provided with a first sawtooth structure, the metal upper cover is provided with a second sawtooth structure, and the first sawtooth structure and the second sawtooth structure are arranged on the battery shell. The first sawtooth structure and the second sawtooth structure are meshed with each other to realize splicing of the metal lower cover and the metal upper cover, a mounting cavity is formed in the battery shell, and receding structures are arranged at four corners of the battery shell; the battery is fixed in the mounting cavity, so that the battery shell covers the battery, positive and negative tabs are led out of the battery, the positive and negative tabs are externally connected with a wire harness, and one end of the wire harness penetrates through the battery shell and is used for being externally connected with other equipment; and the protection piece is arranged on the outer surface of the battery. The invention also provides a preparation method of the lithium battery. The capacity of the same-volume battery is improved, the potential safety risk of the battery is solved, and the production cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of lithium battery technology, and in particular to a lithium battery with a metal casing structure and its preparation method. Background Technology

[0002] Metal-cased pack technology is a key technology in battery system and electronic module packaging. It mainly uses metal materials (such as steel, aluminum or alloys) as the outer shell to provide robust physical protection, efficient heat dissipation, reliable electromagnetic shielding and good sealing for the internal battery or chip.

[0003] Existing metal-cased PACK technologies widely employ various techniques such as low-temperature injection molding, ultrasonic injection, and hybrid methods. However, these methods may face numerous challenges, including high process complexity, difficulty in controlling costs, limited production efficiency, and decreased reliability under certain special environments. These issues can have varying degrees of impact on overall product quality, battery capacity limitations, and performance. Summary of the Invention

[0004] The purpose of this invention is to overcome the above-mentioned defects in the prior art and provide a lithium battery with a metal casing structure and its preparation method. This invention aims to improve the capacity of batteries of the same volume, effectively enhance the structural strength of the battery, solve the potential safety risks of the battery, meet relevant regulatory requirements, achieve battery removability, and effectively reduce production costs.

[0005] To achieve the above objectives, the present invention provides a lithium battery with a metal casing structure, comprising:

[0006] A battery casing, comprising a lower metal cover and a upper metal cover, wherein the lower metal cover is provided with a first serrated structure and the upper metal cover is provided with a second serrated structure, wherein the first serrated structure and the second serrated structure engage with each other to achieve splicing of the lower metal cover and the upper metal cover, wherein an installation cavity is provided inside the battery casing, and wherein clearance structures are provided at the four corners of the battery casing.

[0007] A battery is fixed in the mounting cavity such that the battery casing covers the battery. The battery has positive and negative leads, and the positive and negative leads are connected to a wire harness. One end of the wire harness passes through the battery casing for connecting to other devices.

[0008] A protective element is disposed on the outer surface of the battery.

[0009] Furthermore, the lower metal cover includes a lower cover body and four sets of lower cover sidewalls respectively vertically arranged on the four sides of the lower cover body, with a first gap between adjacent lower cover sidewalls. The upper metal cover includes an upper cover body and four sets of upper cover sidewalls respectively vertically arranged on the four sides of the upper cover body, with a second gap between adjacent sets of upper cover sidewalls. The first gap and the second gap are aligned to form the clearance structure. The first gap and the second gap are respectively set in the upper metal cover and the lower metal cover, which can not only splice together to form a clearance structure to avoid the risk of punctures and scratches caused by metal deformation after the battery is dropped into the drum, but also effectively reduce assembly stress and improve the stability of the overall structure of the casing. At the same time, this structure can be directly formed by stamping and bending, which can reduce production difficulty and cost.

[0010] Furthermore, the four sets of lower cover sides and the lower cover body together form a first cavity, and the four sets of upper cover sides and the upper cover body together form a second cavity. The first cavity and the second cavity are combined to form the mounting cavity. The mounting cavity is used to accommodate the battery and provide a uniform stress distribution.

[0011] Furthermore, the first serrated structure includes several sets of first protruding teeth and first grooves alternately arranged on the side of the lower cover, and the second serrated structure includes several sets of second protruding teeth and second grooves alternately arranged on the side of the upper cover. The first protruding teeth engage with the second grooves, and the second protruding teeth engage with the first grooves. Structurally, the metal upper cover and the metal lower cover are tightly connected through the alternating engagement of the protruding teeth and grooves, enhancing the structural strength of the shell and ensuring assembly accuracy. In terms of processing, the assembly is simple and efficient, and the production cost is expected to be reduced by 50% compared to similar metal laser / resistance / soldering processes, and by 50% compared to low-temperature and ultrasonic processes. At the same time, this process is suitable for automated operation, significantly increasing the output per unit time and significantly reducing labor costs.

[0012] Furthermore, the edges and corners of the first and / or second protruding teeth are rounded, and the bottom corners of the first and / or second grooves are also rounded. The rounded corner structure effectively avoids stress concentration, improves the fatigue resistance of the connection parts, and reduces metal shavings during assembly, lowering the risk of short circuits. The rounded corner design also facilitates mold release, improves stamping yield, and further reduces manufacturing costs.

[0013] Furthermore, the meshing distance between the first and second sawtooth structures is no greater than 0.3 mm. This design, where the meshing distance between the first and second sawtooth structures is no greater than 0.3 mm, avoids the risk of internal short circuits caused by sharp objects such as blades or screwdrivers puncturing the surface.

[0014] Furthermore, the protective component is a PBO fiber material component, which is disposed on the four side wings of the battery or covers the outer surface of the battery. This PBO fiber material (short for poly-p-phenylene benzobisoxazole fiber) component has excellent heat resistance, impact resistance, and electrical insulation properties, effectively protecting the battery under high temperature or mechanical shock environments, preventing thermal runaway and internal short circuits; its low dielectric constant and high mechanical strength also reduce the influence of external electromagnetic interference, improving the overall safety of the battery system.

[0015] Furthermore, a first channel for the wire harness to pass through is provided on the battery casing, and the sidewall of the first channel has an arc structure. This avoids damage to the insulation layer due to friction from sharp corners during wire harness insertion, improving assembly safety and durability. The through-hole positions are precisely laid out to ensure a reasonable wire harness routing, reduce internal stress concentration, and facilitate positioning and threading by automated equipment, further improving production efficiency and product consistency.

[0016] Furthermore, the battery is adhered to the inside of the mounting cavity using double-sided adhesive. The double-sided adhesive serves both cushioning and fixing functions, effectively suppressing battery displacement under vibration or impact conditions, facilitating quick locking and disassembly of the casing, enabling convenient maintenance and replacement, and reducing the risk of mechanical damage to the battery body.

[0017] Furthermore, latches are provided on the metal upper cover and / or metal lower cover. These latches facilitate quick engagement with the latching structures of other components, improving overall assembly efficiency and usability.

[0018] This invention also provides a method for preparing a lithium battery with a metal casing structure, comprising the following steps:

[0019] S1. Provides a battery, a protective component, a metal lower cover, and a metal upper cover, and forms a first serrated structure and a second serrated structure on the metal lower cover and the metal upper cover, respectively.

[0020] S2, Battery leads out positive and negative leads, positive and negative leads are connected to external wiring harness;

[0021] S3. Attach the protective components to the outer surface of the battery;

[0022] S4. Attach double-sided tape to the bottom of the battery and use the double-sided tape to directly attach the battery to the inside of the metal bottom cover;

[0023] S5. Then, the metal top cover and the metal bottom cover are spliced ​​together so that the first sawtooth structure and the second sawtooth structure mesh with each other. After the metal top cover and the metal bottom cover are spliced ​​together, they form the battery casing, which wraps the main body of the battery. The double-sided adhesive on the upper surface of the battery is bonded to the inner wall of the metal top cover.

[0024] S6. Finally, attach labels to the outer surfaces of the metal bottom cover and the metal top cover.

[0025] Compared with the prior art, the present invention has the following advantages:

[0026] Under the condition of the same battery pack volume, this invention can significantly optimize the internal structural layout compared with the widely used low-temperature injection molding, ultrasonic, and hybrid solutions in the industry, thereby maximizing the effective use of space in the battery. This design advantage directly translates into higher energy storage capacity, increasing the capacity contribution by more than 20%. This not only enhances the overall performance of the battery but also provides more reliable power support for various application scenarios. At the same time, the production is simple and efficient. With the aid of positioning fixtures, the production cost is expected to be reduced by 50% compared with similar metal laser / resistance / soldering processes, and by 50% compared with low-temperature and ultrasonic processes. In addition, this process is suitable for automated operation, greatly increasing the output per unit time and significantly reducing labor costs.

[0027] Through the collaborative structural design of the metal top cover and the metal bottom cover, the battery can be fully covered, avoiding safety risks caused by abnormal squeezing or puncture of the battery and lithium battery protection board. At the same time, the tight meshing of the first and second sawtooth structures, together with the rigid protection of the metal shell, further suppresses the transmission of external impact force to the battery body. Combined with the high tensile strength of PBO fiber material, multiple safety barriers are formed, which can also effectively prevent fire and flame, isolate external high temperature, and dissipate internal temperature.

[0028] Furthermore, the design and reasonable arrangement of the air-proof structure of the battery casing can effectively avoid the risk of failure such as puncture or scratch that may be caused by deformation of the metal casing after the battery has undergone drop or tumbling tests. By reserving sufficient buffer space and deformation allowance, this structure disperses and absorbs external impact energy, thereby protecting the internal battery from damage and improving the mechanical safety and reliability of the battery module. Attached Figure Description

[0029] To more clearly illustrate the technology in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the structure of a lithium battery with a metal casing according to the present invention;

[0031] Figure 2 yes Figure 1 A magnified view of region A;

[0032] Figure 3 This is a schematic diagram of the structure of the present invention, which is wrapped with an elastic label covering layer;

[0033] Figure 4 yes Figure 3 A diagram showing the decomposition of parts;

[0034] Figure 5 This is an exploded structural diagram of the battery casing of the present invention;

[0035] Figure 6 This is a schematic diagram of the structure of the metal lower cover of the present invention;

[0036] Figure 7 This is a schematic diagram of the structure of the metal top cover of the present invention.

[0037] The diagram includes:

[0038] 1. Battery casing; 11. Metal lower cover; 111. Lower cover body; 112. Lower cover side; 113. First gap; 114. First cavity; 115. First recessed structure; 12. Metal upper cover; 121. Upper cover body; 122. Upper cover side; 123. Second gap; 124. Second cavity; 125. Second recessed structure; 13. First serrated structure; 131. First protruding tooth; 132. First groove; 14. Second serrated structure; 141. Second protruding tooth; 142. Second groove; 15. Mounting cavity; 16. Clearance structure; 17. First channel; 18. Engaging gap; 2. Battery; 21. Positive and negative tabs; 3. Protective component; 4. Double-sided adhesive; 5. Protective insulation layer; 6. Wiring harness; 7. Protective plate; 71. Insulation layer; 8. Locking buckle; 9. Elastic label covering layer. Detailed Implementation

[0039] The technology of this embodiment of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiment is one embodiment of the present invention, and not all embodiments thereof. Based on this embodiment of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0040] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0041] Furthermore, if the embodiments of the present invention involve descriptions such as "first" or "second", such descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated.

[0042] like Figures 1 to 7 The present invention discloses a lithium battery with a metal casing structure, including a battery casing 1, a battery 2 and a protective component 3;

[0043] like Figure 1 and Figure 2 As shown, the battery housing 1 in this embodiment includes a lower metal cover 11 and a upper metal cover 12. The lower metal cover 11 is provided with a first serrated structure 13, and the upper metal cover 12 is provided with a second serrated structure 14. The lower metal cover 11 and the upper metal cover 12 are joined together by the first serrated structure 13 and the second serrated structure 14 to form the battery housing 1. An installation cavity 15 is provided inside the battery housing 1, and a clearance structure 16 is provided at the four corners of the battery housing 1.

[0044] Preferably, such as Figures 4 to 6 As shown, in this embodiment, the metal lower cover 11 includes a lower cover body 111 and four sets of lower cover side edges 112 respectively vertically disposed on the four sides of the lower cover body 111. The lower cover body 111 and the lower cover side edges 112 can be directly stamped and formed. A bend is formed between the lower cover side edges 112 and the lower cover body 111. This bend is set as an arc transition structure to reduce stress concentration and improve structural strength. A first gap 113 is provided between two adjacent sets of lower cover side edges 112. Similarly, as... Figure 6 As shown, the aforementioned metal cover 12 includes a cover body 121 and four sets of cover side edges 122 respectively vertically disposed on the four sides of the cover body 121. The cover body 121 and the cover side edges 122 can also be directly stamped. A bend is formed between the cover side edges 122 and the cover body 121. This bend is configured as an arc transition structure to reduce stress concentration and improve structural strength. A second gap 123 is provided between two adjacent sets of cover side edges 122, such as... Figure 2 As shown, the first gap 113 and the second gap 123 are spliced ​​together to form a clearance structure 16. The first gap 113 and the second gap 123 are respectively set on the metal upper cover 12 and the metal lower cover 11. This not only allows the clearance structure 16 to be spliced ​​together to avoid the risk of puncture and scratch failure caused by metal deformation of the battery 2 after falling into the roller, but also effectively reduces assembly stress and improves the stability of the overall shell structure. At the same time, this structure can reduce production difficulty and cost through stamping and bending.

[0045] The aforementioned metal upper cover 12 and metal lower cover 11 are made of the same metal sheet, preferably aluminum alloy or stainless steel, which has good thermal conductivity and mechanical strength. The lower cover side 112 and the upper cover side 122 are paired and parallel to each other. When the first serrated structure 13 and the second serrated structure 14 engage, the lower cover side 112 and the upper cover side 122 partially overlap along the thickness direction, forming a stable splicing structure, which effectively improves the pressure resistance of the shell. At the same time, the four sets of lower cover side 112 and the lower cover body... The body 111 forms a first cavity 114, and the four sets of upper cover side edges 122 and the upper cover body 121 form a second cavity 124. The first cavity 114 and the second cavity 124 are combined to form a mounting cavity 15, which is used to accommodate the battery 2 and the protective component 3. Specifically, a buffer gap is provided between the inner wall of the mounting cavity 15 and the outer surface of the battery 2 to further absorb the expansion stress of the battery 2 and improve battery safety. In this embodiment, the battery 2 is installed in the mounting cavity 15 so that the battery casing 1 covers the battery 2.

[0046] The protective component 3 wraps around the front and left and right wings of the battery 2. After the battery 2 is installed in the mounting cavity 15, the protective component 3 is placed in the buffer gap and closely fits the meshing parts of the first serrated structure 13 and the second serrated structure 14, effectively dispersing external impact forces and preventing damage to the battery 2 caused by concentrated force. At the same time, the protective component 3 is a component made of PBO fiber material. The PBO fiber material (abbreviation of poly-p-phenylene benzobisoxazole fiber) has excellent heat resistance, impact resistance and electrical insulation properties, which can effectively protect the battery 2 in high temperature or mechanical impact environments and prevent thermal runaway and internal short circuits. Its low dielectric constant and high mechanical strength characteristics can also reduce the influence of external electromagnetic interference and improve the overall safety of the battery system. Therefore, the setting of the protective component 3 can isolate the meshing gap 18 of the meshing parts, forming a good internal sealing space, and can also constitute the meshing split structure of the present invention. This not only reduces production costs, but also improves assembly efficiency and structural reliability. Moreover, the lightweight characteristics of PBO fiber material help to reduce the overall weight of the battery and further improve energy density.

[0047] Of course, in other embodiments, the protective component 3 can completely cover the upper and lower surfaces and all outer surfaces of the side wings of the battery 2 to enhance all-round protection capabilities. In this case, the protective component 3 is closely attached to the inner walls of the upper cover body 121 and the lower cover body 111 to form a continuous insulating barrier, effectively suppressing partial discharge and heat conduction. This covering structure is particularly suitable for high energy density batteries 2 or extreme working conditions, and can significantly improve the safety margin of the battery module.

[0048] Furthermore, the protective component 3 is a PBO fiber material component, and the protective component 3 is disposed on the side wing of the battery 2 or covers the outer surface of the battery 2.

[0049] In this embodiment, the battery 2 is directly bonded to the upper cover body 121 and the lower cover body 111 using double-sided adhesive 4, achieving rapid positioning and a firm connection while avoiding the risk of heat damage from welding. The double-sided adhesive 4 layer has good temperature resistance and shear strength, maintaining stable adhesion performance over a wide temperature range, effectively transferring and dispersing stress, and preventing uneven stress on the battery 2 caused by casing deformation. Preferably, during assembly, the protective component 3 is first installed on the side wing or outer surface of the battery 2, and then the battery 2 with the double-sided adhesive 4 bonded to it is placed into the upper cover body 121. Between the cover body 121 and the lower cover body 111, the protective component 3 is tightly engaged with the first serrated structure 13 and the second serrated structure 14 through pressing, thereby improving the overall structural integrity. This assembly method not only ensures a gapless fit between the protective component 3 and the shell, but also effectively suppresses interface slippage through the high modulus characteristics of PBO fiber material, enhancing the resistance to vibration and impact. At the same time, due to the synergistic effect of the double-sided adhesive layer 4 and the protective component 3, the volume change during the charging and discharging process of the battery 2 can be buffered, reducing the accumulation of fatigue stress and extending the battery life.

[0050] An additional protective insulating layer 5 is provided on the left and right sides of the protective component 3 to protect the side wings of the battery.

[0051] like Figure 4 As shown, battery 2 has positive and negative tabs 21 at the front end, and wire harness 6 is connected to the positive and negative tabs 21. The other end of wire harness 6, away from battery 2, passes through battery housing 1 for connecting to other devices. Preferably, a protective plate 7 is provided at the connection between positive and negative tabs 21 and wire harness 6 to fix the welding position of positive and negative tabs 21 and wire harness 6. At the same time, an insulating layer 71 is wrapped around the protective plate 7 to prevent high voltage discharge or short circuit risk. The insulating layer 71 is made of high temperature resistant epoxy resin material, which has excellent dielectric properties and mechanical strength and can effectively resist vibration wear and environmental moisture intrusion. The protective plate 7 can be fixed to the inside of battery housing 1 by laser welding, and the connection is reliably sealed, further improving the overall safety level.

[0052] To further facilitate the passage of the wiring harness 6, this embodiment provides a first channel 17 on the battery casing 1 for the wiring harness 6 to pass through. The sidewall of the first channel 17 is an arc structure. In this embodiment, a first recessed groove structure 115 is provided at the corresponding position of the lower metal cover 11. Similarly, a second recessed groove structure 125 that cooperates with the first recessed groove structure 115 is provided at the corresponding position of the upper metal cover 12, as detailed below. Figure 6 and Figure 7As shown, the first recessed groove structure 115 is disposed on the lower cover side 112 at the front end of the lower metal cover 11, and the second recessed groove structure 125 is disposed on the upper cover side 122 at the front end of the upper metal cover 12. The two recessed grooves are joined together to form a first channel 17 for accommodating the wire harness 6. The first recessed groove structure 115 and the second recessed groove structure 125 are formed by stamping and then folding a local area of ​​the upper metal cover 12 and the lower metal cover 11 to ensure that the edge of the groove is smooth and burr-free, so as to avoid damage to the wire harness 6 when it is inserted. The depth of the groove matches the diameter of the wire harness 6, and the double-sided adhesive 4 sealing layer achieves fastening, limiting and insulation isolation, effectively preventing wear or short circuit risks caused by vibration.

[0053] like Figure 6 and Figure 7 As shown, the first serrated structure 13 includes several sets of first protruding teeth 131 and first grooves 132 sequentially and continuously arranged on the side 112 of the lower cover. The second serrated structure 14 includes several sets of second protruding teeth 141 and second grooves 142 sequentially and continuously arranged on the side 122 of the upper cover. The first protruding teeth 131 and the second grooves 142 mesh, and the second protruding teeth 141 and the first grooves 132 mesh. Structurally, the metal upper cover 12 and the metal lower cover 11 are tightly connected through the staggered meshing of the first protruding teeth 131 and the second grooves 142, and the second protruding teeth 141 and the first grooves 132, which enhances the structural strength of the shell and ensures assembly accuracy. In terms of processing, the assembly is simple and efficient, and the production cost is expected to be reduced by 50% compared with the same type of metal laser / resistance / soldering welding, and by 50% compared with the same low temperature and ultrasonic processes. At the same time, this process is suitable for automated operation, which greatly increases the output per unit time and greatly reduces labor costs.

[0054] In this embodiment, the apex corner of the first protrusion 131 can be set as a rounded corner, the bottom corner of the first groove 132 can be set as a rounded corner, and the apex corner of the second protrusion 141 and the bottom corner of the second groove 142 can be kept at right angles; of course, the apex corner of the second protrusion 141 and the bottom corner of the second groove 142 can also be set as rounded corners, while the apex corner of the first protrusion 131 and the bottom corner of the first groove 132 can be kept at right angles; or all the apex corners of the first protrusion 131, the apex corners of the second protrusion 141, the bottom corners of the first groove 132 and the bottom corners of the second groove 142 can be designed as rounded corner structures to further disperse stress concentration and improve the fatigue durability of the shell under dynamic loads; this geometric optimization not only enhances the reliability of interface meshing, but also reduces the risk of material cracking during stamping and improves the yield. In the actual assembly process, the metal upper cover 12 and the lower cover are joined together along the side and radial pressure is applied, so that the first protrusion 131 is embedded in the second groove 142, and the second protrusion 141 is simultaneously embedded in the first groove 132, forming a bidirectional interlocking structure, which effectively transmits and disperses external impact loads. The rounded corner design also helps the mold to be demolded, improves the stamping yield, and further reduces manufacturing costs.

[0055] At the same time, such as Figure 2 As shown, in this embodiment, the meshing distance 18 between the first serrated structure 13 and the second serrated structure 14 is no greater than 0.3mm. This meshing distance 18 design avoids the risk of internal short circuit caused by sharp objects such as blades and screwdrivers piercing the metal. Specifically, the meshing distance 18 is the gap formed between the metal lower cover 11 and the metal upper cover 12 after the first serrated structure 13 and the second serrated structure 14 mesh together.

[0056] In some embodiments, a latch 8 is provided on the metal upper cover 12. The latch 8 facilitates quick engagement with the latch 8 structures of other components, improving the assembly efficiency and practicality of the whole machine. It should be noted that the latch 8 can also be provided on the metal lower cover 11. The specific position can be adjusted according to the overall structural layout and assembly requirements. The latch 8 can be symmetrically or asymmetrically distributed on the side edges to improve connection stability and disassembly convenience. Of course, it can also be provided on both the metal upper cover 12 and the metal lower cover 11 to form a multi-point locking structure, further improving the overall connection strength and shock resistance. The latch 8 is made of elastic metal sheet integrally stamped, with good resilience and durability. It maintains stable engagement force after tens of thousands of insertion and removal tests, ensuring that it is not easy to loosen during long-term use.

[0057] Finally, to further enhance the sealing performance, an elastic label covering layer 9 can be wrapped around the metal upper cover 12 and the metal lower cover 11. This elastic label is made of thermoplastic polyurethane material and is molded to fit tightly against the outer edge of the shell, effectively blocking the intrusion of moisture and dust. It also has excellent UV resistance and weather resistance, avoiding delamination or curling caused by environmental changes. The surface of this covering layer can integrate information such as QR codes and brand logos, which has both anti-counterfeiting and aesthetic functions. It is also integrated with the shell through injection molding, significantly improving the protection level to IP68 standard and meeting the sealing requirements under harsh working conditions.

[0058] This invention also provides a method for preparing a lithium battery with a metal casing structure, specifically including the following steps:

[0059] S1. Provide battery 2, protective component 3, metal lower cover 11 and metal upper cover 12, and form a first serrated structure 13 and a second serrated structure 14 on the metal lower cover 11 and metal upper cover 12 respectively. Specifically, the metal lower cover 11 and metal upper cover 12 are both directly stamped and formed, and their four sides are bent to form the lower cover side 112 and the upper cover side 122. The bending is set as an arc transition structure.

[0060] S2, battery 2 leads out positive and negative leads 21, positive and negative leads 21 external wiring harness 6;

[0061] S3. Attach the protective component 3 to the outer surface of the battery 2;

[0062] S4. Apply double-sided tape to the top and bottom ends of battery 2 and directly attach battery 2 to the inside of the metal lower cover 11 using the double-sided tape.

[0063] S5. Then, the metal upper cover 12 and the metal lower cover 11 are spliced ​​together so that the first serrated structure 13 and the second serrated structure 14 mesh with each other. After the metal upper cover 12 and the metal lower cover 11 are spliced ​​together, they form the battery casing 1, which wraps the main body of the battery 2. The double-sided adhesive 4 on the upper surface of the battery 2 is bonded to the inner wall of the metal upper cover 12. After the metal upper cover 12 and the metal lower cover 11 are spliced ​​together, a first channel 17 is formed for the wire harness 6 to pass through.

[0064] S6. Finally, label the outer surfaces of the metal lower cover 11 and the metal upper cover 12 to perform the functional test.

[0065] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A lithium battery with a metal casing structure, characterized in that, include: The battery housing (1) includes a metal lower cover (11) and a metal upper cover (12). The metal lower cover (11) is provided with a first serrated structure (13), and the metal upper cover (12) is provided with a second serrated structure (14). The first serrated structure (13) and the second serrated structure (14) mesh with each other to realize the splicing of the metal lower cover (11) and the metal upper cover (12). An installation cavity (15) is provided inside the battery housing (1), and a clearance structure (16) is provided at the four corners of the battery housing (1). Battery (2), the battery (2) is fixed in the mounting cavity (15) so that the battery housing (1) covers the battery (2), the battery (2) leads out positive and negative tabs (21), the positive and negative tabs (21) are connected to a wire harness (6), one end of the wire harness (6) passes through the battery housing (1) for connecting other devices; A protective element (3) is disposed on the outer surface of the battery (2).

2. A lithium battery with a metal casing structure according to claim 1, characterized in that, The lower metal cover (11) includes a lower cover body (111) and four sets of lower cover sidewalls (112) respectively vertically arranged on the four sides of the lower cover body (111). A first gap (113) is provided between adjacent lower cover sidewalls (112). The upper metal cover (12) includes an upper cover body (121) and four sets of upper cover sidewalls (122) respectively vertically arranged on the four sides of the upper cover body (121). A second gap (123) is provided between two adjacent sets of upper cover sidewalls (122). The first gap (113) and the second gap (123) are aligned to form the clearance structure (16).

3. A lithium battery with a metal casing structure according to claim 2, characterized in that, The four sets of lower cover side edges (112) and the lower cover body (111) together form a first cavity (114), and the four sets of upper cover side edges (122) and the upper cover body (121) together form a second cavity (124). The first cavity (114) and the second cavity (124) are combined to form the mounting cavity (15).

4. A lithium battery with a metal casing structure according to claim 2, characterized in that, The first serrated structure (13) includes several sets of first protruding teeth (131) and first grooves (132) alternately arranged on the side of the lower cover (112). The second serrated structure (14) includes several sets of second protruding teeth (141) and second grooves (142) alternately arranged on the side of the upper cover (122). The first protruding teeth (131) mesh with the second grooves (142), and the second protruding teeth (141) mesh with the first grooves (132).

5. A lithium battery with a metal casing structure according to claim 4, characterized in that, The corners of the first protrusion (131) and / or the second protrusion (141) are rounded, and the bottom corners of the first groove (132) and / or the second groove (142) are rounded.

6. A lithium battery with a metal casing structure according to claim 1, characterized in that, The meshing distance (18) between the first sawtooth structure (13) and the second sawtooth structure (14) is not greater than 0.3 mm.

7. A lithium battery with a metal casing structure according to claim 1, characterized in that, The protective component (3) is a PBO fiber material component, and the protective component (3) is disposed on the side wing of the battery (2) or the protective component (3) covers the outer surface of the battery (2).

8. A lithium battery with a metal casing structure according to claim 1, characterized in that, A first channel (17) for passing through the wire harness (6) is provided on the battery housing (1), and the sidewall of the first channel (17) is an arc structure.

9. A lithium battery with a metal casing structure according to claim 1, characterized in that, A latch (8) is provided on the metal upper cover (12) and / or the metal lower cover (11).

10. A method for preparing a lithium battery with a metal casing structure according to any one of claims 1-9, characterized in that, Includes the following steps: S1. Provide a battery (2), a protective component (3), a metal lower cover (11) and a metal upper cover (12), and form a first serrated structure (13) and a second serrated structure (14) on the metal lower cover (11) and the metal upper cover (12) respectively. S2, the battery (2) leads out the positive and negative terminals (21), and the positive and negative terminals (21) are connected to the external wiring harness (6). S3. Attach the protective component (3) to the outer surface of the battery (2); S4. Apply double-sided tape (4) to the upper and lower end faces of the battery (2) and directly attach the battery (2) to the inside of the metal lower cover (11) using the double-sided tape (4); S5. Then, the metal top cover (12) and the metal bottom cover (11) are spliced ​​together so that the first serrated structure (13) and the second serrated structure (14) mesh with each other. The metal top cover (12) and the metal bottom cover (11) are spliced ​​together to form a battery shell (1) that wraps the main body of the battery (2). The double-sided adhesive (4) on the upper surface of the battery (2) is bonded to the inner wall of the metal top cover (12). S6. Finally, attach labels to the outer surfaces of the metal lower cover (11) and the metal upper cover (12).

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