Battery cover plate and manufacturing method therefor, and battery and processing method therefor

Abstract

A battery cover plate (1). The battery cover plate (1) is used for closing a battery housing (3) to form a battery (100), and the battery cover plate (1) comprises a cover plate body (11), a pole (12), and an insulating member (13). A first through hole (111) is formed in the cover plate body (11), a plurality of first micropores (112) are formed in the inner wall of the first through hole (111), a plurality of second micropores (122) are formed in the outer wall of the pole (12), the insulating member (13) is arranged between the pole (12) and the cover plate body (11), and the insulating member (13) at least partially invades the first micropores (112) and the second micropores (122). The insulating member (13) fills a space between the pole (12) and the cover plate body (11) by means of injection molding, thereby achieving the isolation and insulation effects, and the pole (12) and the cover plate body (11) are connected into a whole, thereby avoiding relative torsion of the pole (12) and the cover plate body (11) during use, reducing related anti-torsion structures, saving components and related processing processes, and improving the use safety of the battery cover plate (1).

Description

Battery cover and preparation method thereof, battery and processing method thereof

[0001] This application is based on the Chinese invention application with application number 202310959614.1 filed on August 1, 2023, entitled “A battery cover, its preparation method and battery”; the Chinese invention application with application number 202310964758.6 filed on August 1, 2023, entitled “A battery”; and the Chinese invention application with application number CN202310964639.0 filed on August 1, 2023, entitled “Battery monomer processing method”, and claims priority to them. Technical Field

[0002] The present application relates to the field of battery technology, and in particular to a battery cover and a preparation method thereof, a battery and a processing method thereof. Background Art

[0003] With the continuous expansion of the new energy industry, lithium-ion batteries, as an important part of the new energy industry, have been more widely used. Square aluminum shell lithium-ion batteries are widely used in the fields of power and energy storage batteries because of their simple structure, high energy density and high safety performance. Taking lithium-ion batteries as an example of power batteries, the existing lithium-ion batteries mainly have two structures: square lithium-ion batteries and soft-pack lithium-ion batteries. For square lithium-ion batteries, the existing battery cover plate has a complex structure, many components, a complex processing process, and a cumbersome preparation method; moreover, in order to ensure the overall strength of the battery, the thickness of the square aluminum shell used is relatively thick (0.4mm~0.5mm), the processing cost of the thicker square aluminum shell is high, the overall weight of the battery is heavy, and the energy density of the battery is low. For soft-pack lithium-ion batteries, the shell is made of stamped aluminum-plastic film. The pole core assembly is then melted into the accommodating cavity formed by the aluminum-plastic film by heat-melting. The connecting piece connected to the pole core assembly is also connected to the aluminum-plastic film by heat-melting. The use of aluminum-plastic film and heat-melting sealing has problems such as poor sealing, poor thermal conductivity, low lifespan, and battery leakage. In addition, in the battery production process, the battery cell is the smallest unit of the battery system and is also called a battery cell. Multiple battery cells form a module, and multiple modules form a battery system. The process flow of battery cells includes three stages: pole piece preparation, battery cell assembly, and formation testing.

[0004] In the existing hard-shell battery cell manufacturing process, battery cell assembly requires a series of steps, including casing, welding the positive and negative tabs to the positive and negative cover plates, gluing the weld points, folding the tabs and pressing the cover plates, pre-spot welding the cover, and finally sealing the positive and negative cover plates. In casing, the bare cell, wrapped in an insulating film, is placed into the shell cavity from the shell opening. Existing techniques require sucking the shell opening and then repeatedly pushing the bare cell through the shell opening to slowly enter the shell cavity. There are many problems with this shell-wrapping method. First, it requires zero tolerance for burrs on the shell opening, which increases the cost of shell production. Second, the shell opening can easily damage the bare battery cell during multiple pushes and the processing efficiency is very low. In addition, since the shell opening may be deformed when it is sucked, it makes it difficult to weld the shell cover, resulting in an increase in the welding defect rate. Finally, this shell-wrapping method can only determine the relative position of the bare battery cell and the cover plate after the shell is wrapped. Therefore, when welding the shell cover, it is necessary to reserve operating space to perform the actions of folding the pole ears and pressing the cover plate, which increases the difficulty of assembly and the complexity of the operation process.

[0005] Therefore, how to overcome the above-mentioned technical problems and defects becomes a key issue that needs to be solved.

[0006] Summary of the Invention

[0007] In response to the problems of complex structure, multiple components and complicated processing process of existing battery cover plates, the present application provides a battery cover plate and a preparation method thereof, a battery and a processing method thereof.

[0008] The technical solutions adopted by this application to solve the above technical problems are as follows:

[0009] A battery cover is used to enclose a battery shell to form a battery. The battery cover includes a cover body, a pole and an insulating member. The cover body is provided with a first through hole, the inner wall of the first through hole is formed with a plurality of first micropores, the outer wall of the pole is formed with a plurality of second micropores, the insulating member is arranged between the pole and the cover body, and the insulating member at least partially invades the first micropores and the second micropores.

[0010] A method for preparing a battery cover: used to prepare the battery cover described above, comprising the following steps:

[0011] Step 1, sequentially subjecting the cover plate body and the electrode to degreasing, water washing, alkali washing, water washing, acid washing, water washing, alkali washing, water washing, electrolytic oxidation, water washing, nano-treatment, water washing, and drying to obtain the cover plate body and the electrode with slightly corroded surfaces;

[0012] Step 2: inserting the slightly corroded pole into the first through hole of the cover body, and forming the insulating member between the cover body and the pole by injection molding.

[0013] A battery comprises a pole core assembly, at least two battery cover plates as described above, and a metal shell assembly, wherein the pole core assembly is connected to the battery cover plate, and the metal shell assembly comprises a first metal shell and a second metal shell, the first metal shell and the second metal shell are sealed and connected, and the first metal shell and the second metal shell are both provided with a receiving groove and a welding skirt, the two receiving grooves are arranged relative to each other to form a receiving cavity for receiving the pole core assembly, the welding skirt is arranged on the outer periphery of the open end of the receiving groove, and the welding skirt extends from the open end of the receiving groove in a direction away from the receiving groove, and the two welding skirts are sealed and welded; the battery cover plate is welded between the two welding skirts.

[0014] A method for processing the battery as described above, comprising:

[0015] Prepare the pole core assembly, the two battery cover plates, the first metal shell, and the second metal shell, wherein the two battery cover plates are respectively a positive electrode cover plate and a negative electrode cover plate, the first end of the pole core assembly is a positive electrode tab, and the second end of the pole core assembly is a negative electrode tab;

[0016] Welding the positive electrode tab and the positive electrode cover plate, and welding the negative electrode tab and the negative electrode cover plate to obtain a first assembly;

[0017] coating the first component with an insulating film;

[0018] The first assembly coated with the insulating film is placed into a housing space formed by the first metal shell and the second metal shell, thereby obtaining a second assembly; the housing space has a first opening and a second opening opposite to each other; the positive electrode cover plate is installed in the first opening, and the negative electrode cover plate is installed in the second opening;

[0019] The second component is subjected to shaping processing by a shaping mold so that the first metal shell and the second metal shell are bonded to each other, the positive electrode cover plate is bonded to the first metal shell and the second metal shell, and the negative electrode cover plate is bonded to the first metal shell and the second metal shell;

[0020] performing sealing welding on the reshaped second component to seal the accommodating space;

[0021] The sealed second assembly is post-processed to obtain a battery cell.

[0022] Compared with the prior art, the battery cover provided by this application has the following main effects:

[0023] (1) The present application provides an insulating member in the first through hole, thereby isolating the pole and the cover body, preventing the pole and the cover body from contacting each other, and achieving a technical effect of insulating the pole and the cover body;

[0024] (2) The insulating member of the present application is filled between the pole and the cover body by injection molding, connecting the pole and the cover body into a whole, preventing the pole from twisting relative to the cover body during use, and reducing the related anti-twist structure;

[0025] (3) In the present application, a plurality of first micropores are formed on the inner wall of the first through hole and a plurality of second micropores are formed on the outer wall of the pole. The insulating member is filled between the pole and the cover body by injection molding and intrudes into the first micropores and the second micropores, thereby improving the connection strength between the pole and the cover body and connecting the pole and the cover body into a whole.

[0026] (4) The provision of the insulating member of the present application not only has the technical effect of isolating the pole and the cover body from the insulating member, but also connects the pole and the cover body into a whole, and has the technical effect of an anti-torsion structure. Therefore, the provision of the insulating member of the present application reduces the use of insulating members and / or anti-torsion structures, making the structure of the battery cover of the present application simple, using fewer parts, and at the same time, the processing method is simple, the processing cost is low, and the parts and related processing processes are saved, and the use effect is good;

[0027] (5) The extended structure on both sides of the cover body can be sealed and fitted with the battery shell through welding, ensuring the sealing and safety of the battery, thereby improving the safe use performance of the battery cover. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0029] FIG1 is a schematic structural diagram of a battery cover provided in a first embodiment of the present application;

[0030] FIG2 is an exploded schematic diagram of a battery cover provided in the first embodiment of the present application;

[0031] FIG3 is a schematic top view of a battery cover provided in the first embodiment of the present application;

[0032] FIG4 is a first cross-sectional schematic diagram of AA in FIG3 ;

[0033] FIG5 is a partial enlarged schematic diagram of portion B in FIG4 ;

[0034] FIG6 is a second cross-sectional schematic diagram of AA in FIG3 ;

[0035] FIG7 is a schematic diagram of a battery explosion provided in the first embodiment of the present application;

[0036] FIG8 is a schematic diagram of the structure of the second metal shell of the present application;

[0037] FIG9 is a schematic diagram of the battery structure provided by the first embodiment of the present application;

[0038] FIG10 is a schematic flow chart of a battery cell processing method in the first embodiment of the present application;

[0039] FIG11 is a schematic diagram of the cover plate and tab welding of the battery cell processing method in the first embodiment of the present application;

[0040] FIG12 is a schematic diagram of a battery cell shaping method according to the first embodiment of the present application;

[0041] FIG13 is a schematic diagram of a first sealing weld of a battery cell processing method according to the first embodiment of the present application;

[0042] FIG14 is a schematic diagram of a second sealing weld of the battery cell processing method in the first embodiment of the present application.

[0043] The reference numerals in the drawings of the specification are as follows: 100 - battery; 1 - battery cover; 11 - cover body; 111 - first through hole; 112 - first microhole; 113 - third microhole; 114 - fourth microhole; 12 - pole; 121 - groove; 122 - second microhole; 13 - insulating member; 131 - first insulating member; 132 - second insulating member; 133 - third insulating member; 14 - injection hole; 141 - conical sealing plug; 142 - sphere Sealing plug; 15-positive electrode cover plate; 16-negative electrode cover plate; 2-core assembly; 21-pole ear; 211-positive electrode ear; 212-negative electrode ear; 22-insulating film; 3-battery case; 31-first metal case; 32-second metal case; 33-welding skirt; 34-accommodating groove; 41-positive electrode weld; 42-negative electrode weld; 5-shaping mold; 61-first sealing weld; 62-second sealing weld. DETAILED DESCRIPTION

[0044] In order to make the technical problems, technical solutions and beneficial effects solved by this application more clearly understood, this application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0045] As shown in Figures 1-3, in one embodiment, the first aspect of the present application provides a battery cover 1, which is used to enclose a battery shell 3 to form a battery 100. The battery cover 1 includes a cover body 11, a pole 12 and an insulating member 13. A first through hole 111 is provided on the cover body 11, and a plurality of first micropores 112 are formed on the inner wall of the first through hole 111. A plurality of second micropores 122 are formed on the outer wall of the pole 12. The insulating member 13 is arranged between the pole 12 and the cover body 11, and the insulating member 13 at least partially invades the first micropores 112 and the second micropores 122.

[0046] In some embodiments, a plurality of first micropores 112 are formed on the inner wall of the first through hole 111, and a plurality of second micropores 122 are formed on the outer wall of the pole 12, and an insulating member 13 is arranged between the pole 12 and the cover body 11. The insulating member 13 isolates the pole 12 and the cover body 11 to prevent them from contacting each other. The insulating member 13 of the present application is filled between the pole 12 and the cover body 11 by injection molding, and invades the first micropores 112 and the second micropores 122, which not only has the effect of isolation and insulation, but also improves the connection strength between the pole 12 and the cover body 11, connects the pole 12 and the cover body 11 into a whole, avoids relative twisting of the pole 12 and the cover body 11 during use, reduces the relevant anti-twist structure, saves components and related processing flow, and thus improves the safe use performance of the battery cover 1.

[0047] As shown in Figure 2, in one embodiment, the insulating member 13 includes a first insulating member 131, a second insulating member 132 and a third insulating member 133. The first insulating member 131, the second insulating member 132 and the third insulating member 133 are all annular structures. The first insulating member 131, the second insulating member 132 and the third insulating member 133 are integrally formed. The first insulating member 131 and the third insulating member 133 are respectively located at both ends of the second insulating member 132, and the outer diameters of the first insulating member 131 and the third insulating member 133 are both larger than the outer diameter of the second insulating member 132.

[0048] In one embodiment, the thickness direction of the battery cell is the width direction of the cover body 11, the width direction of the battery cell is the length direction of the cover body 11; the length direction of the battery cell is the thickness direction of the cover body 11; the width of the cover body 11 is 0.5-100 mm, the length of the cover body 11 is 20-500 mm; the thickness of the cover body 11 is 2-20 mm;

[0049] In a preferred embodiment, the width of the cover body 11 is 3-50 mm, the length of the cover body 11 is 20-250 mm, and the thickness of the cover body 11 is 3-10 mm.

[0050] Furthermore, along the length of the cover plate body 11, the width of the cover plate body 11 of the present application gradually decreases from the middle to the ends. When the cover plate body 11 is welded to the battery housing 3, the weld seal line must transition from the cover plate body 11 and the battery housing 3 to the battery housing 3 and above the battery housing 3. By setting the width of the cover plate body 11 to gradually decrease from the middle to the ends, it is easier to achieve sealing in the transition area. The extended structure on both sides of the cover plate body 11 can be sealed with the battery housing 3 through welding, ensuring the sealing and safety of the battery 100, thereby improving the safe use performance of the battery cover plate 1.

[0051] In some embodiments, the insulating member 13 is made of PPS, PBT, PPA, etc.

[0052] In some preferred embodiments, the insulating member 13 is made of PPS material, which has good heat resistance, excellent electrical properties, excellent mechanical properties, and good flame retardancy. Furthermore, the insulating member 13 made of PPS material has good dimensional stability.

[0053] As shown in Figure 5, in one embodiment, a plurality of third micropores 113 are formed on the surface of the first end of the cover body 11, a plurality of fourth micropores 114 are formed on the surface of the second end of the cover body 11, the first insulating member 131 at least partially invades the first micropores 112 and the third micropores 113 located outside the first end of the first through hole 111, the second insulating member 132 at least partially invades the first micropores 112 and the second micropores 122, and the third insulating member 133 at least partially invades the first micropores 112 and the fourth micropores 114 located outside the second end of the first through hole 111. The pore diameters of the first micropores 112, the second micropores 122, the third micropores 113 and the fourth micropores 114 are 50-300 nm.

[0054] Specifically, the first insulating member 131 is injection molded on the outside of the first end of the pole 12 protruding from the first through-hole 111 by injection molding. The injection molding range is to inject molding on the surface of the first end of the cover body 11 and extend outward along the outer circumference of the first end of the cover body 11, thereby injecting molding on the surface of the first end of the cover body 11 and part of the outer surface thereof. A plurality of second micropores 122 are formed on the outer wall of the pole 12, and a plurality of third micropores 113 are formed on the surface of the first end of the cover body 11. By injection molding on the outer surface of the cover body 11, the first insulating member 131 isolates the pole 12 and the first end surface of the cover body 11 to prevent them from contacting each other, and invades the third micropores 113 and the second micropores 122, thereby achieving the effect of isolation and insulation and improving the connection strength between the pole 12 and the cover body 11.

[0055] Preferably, when the first insulating member 131 is injection-molded on the outer surface of the cover body 11, the first insulating member 131 leaves a certain width on the outer surface of the cover body 11; this width is conducive to ensuring its sealing connection effect on the one hand, and on the other hand, it also avoids excessive width causing adverse effects on the connection between the battery cover 1, the battery 100 and the battery shell 3.

[0056] In one embodiment, the thickness of the first insulating member 131 is less than the length of the first end of the pole 12 protruding from the first through hole 111; the first end of the first insulating member 131 is lower than the first end of the pole 12, and the first end of the pole 12 protrudes from the first end of the first insulating member 131.

[0057] In one embodiment, the thickness of the first insulating member 131 is equal to the length of the first end of the pole 12 protruding from the first through hole 111 ; the first end of the first insulating member 131 and the first end of the pole 12 are located on the same surface.

[0058] Specifically, a plurality of first micropores 112 are formed on the inner wall of the first through hole 111, and a plurality of second micropores 122 are formed on the outer wall of the pole 12, and the insulating member 13 is arranged between the pole 12 and the cover body 11. The insulating member 13 isolates the pole 12 and the cover body 11 to prevent them from contacting each other. The insulating member 13 of the present application is filled between the pole 12 and the cover body 11 by injection molding, and invades the first micropores 112 and the second micropores 122, which not only has the effect of isolation and insulation, but also improves the connection strength between the pole 12 and the cover body 11, so that the pole 12 and the cover body 11 are connected as a whole.

[0059] Specifically, the third insulating member 133 is injection molded on the outside of the second end of the pole 12 protruding from the first through hole 111 by injection molding. The injection molding range is to inject molding the surface of the second end of the cover body 11 and extend outward along the outer circumference of the second end of the cover body 11 for injection molding, thereby injecting molding the surface of the second end of the cover body 11 and part of the outer surface thereof. A plurality of second micropores 122 are formed on the outer wall of the pole 12, and a plurality of fourth micropores 114 are formed on the surface of the second end of the cover body 11. By injection molding on the outer surface of the cover body 11, the third insulating member 133 isolates the pole 12 and the second end surface of the cover body 11 to prevent them from contacting each other, and invades the fourth micropores 114 and the second micropores 122, which not only has the effect of isolation and insulation, but also improves the connection strength between the pole 12 and the cover body 11.

[0060] By providing the first insulating member 131, the second insulating member 132 and the third insulating member 133, the pole 12 and the cover body 11 are connected as a whole, thereby preventing the pole 12 from twisting relative to the cover body 11 during use, reducing the related anti-twist structure, saving components and related processing procedures, and thus improving the safe use performance of the battery cover 1.

[0061] After the micro-etching treatment is completed, micropores are formed on the surface of the cover body 11 and the pole 12. When the cover body 11 and the pole 12 are made of copper, the pore diameter of the micropores is 50-300nm; when the cover body 11 and the pole 12 are made of aluminum, the pore diameter of the micropores is 10-100nm.

[0062] As shown in FIG. 4 and FIG. 6 , in one embodiment, a liquid injection hole 14 is provided on the cover body 11 , and the liquid injection hole 14 is connected to the interior of the battery housing 3 .

[0063] In one embodiment, an annular groove 121 is provided around the outside of the pole 12 , the first end of the pole 12 passes through the first through hole 111 , and the first end of the pole 12 and the second end of the pole 12 are respectively located on both sides of the first through hole 111 , and the groove 123 is located inside the first through hole 111 .

[0064] Specifically, an annular groove 121 is provided outside the pole 12. The annular groove 121 has the function of increasing the strength of the pole 12. By providing the annular groove 121 outside the pole 12, under the action of external force, the external force will act in the groove 123 instead of acting on the insulating member 13, thereby protecting the insulating member 13.

[0065] Furthermore, the direction from the battery cover 1 to the battery shell 3 is the thickness direction of the pole 12, and the thickness of the pole 12 is greater than the depth of the first through hole 111. During installation, the pole 12 passes through the first through hole 111 and the first end of the pole 12 and the second end of the pole 12 are respectively located on both sides of the first through hole 111, so that the outer wall of the pole 12 is connected to the upper surface, lower surface and inner wall of the first through hole 111 of the cover body 11 through the insulating member 13, thereby increasing the contact area between the insulating member 13 and the pole 12 and the cover body 11, improving the connection strength between the pole 12 and the cover body 11, and connecting the pole 12 and the cover body 11 as a whole, avoiding relative twisting of the pole 12 and the cover body 11 during use, reducing the relevant anti-twist structure, saving components and related processing flow, and thus improving the safe use performance of the battery cover 1.

[0066] As shown in FIG4 and FIG6 , in one embodiment, a sealing plug is further included. The sealing plug is selected from one of a conical sealing plug 141 and a spherical sealing plug 142 . The conical sealing plug 141 or the spherical sealing plug 142 is embedded in the injection hole 14 to seal the injection hole 14 .

[0067] Specifically, the liquid injection hole 14 is in an inverted cone shape, and a conical sealing plug 141 is selected to seal the liquid injection hole 14, thereby achieving a good sealing effect.

[0068] Specifically, the injection hole 14 is an inverted cone, and a spherical sealing plug 142 is selected to seal the injection hole 14. The surface of the spherical sealing plug 142 is an annular protrusion to increase the limiting area at the second end of the injection hole 14, thereby reducing the possibility of the sealing plug escaping from the injection hole 14 to the first end of the cover plate, thereby achieving a good sealing effect.

[0069] A second aspect of the present application provides a method for preparing a battery cover plate 1, which is used to prepare the battery cover plate 1, comprising the following steps:

[0070] Step 1: Degreasing, water washing, alkali washing, water washing, acid washing, water washing, alkali washing, water washing, electrolytic oxidation, water washing, nano-treatment, water washing, and drying the cover plate body 11 and the pole 12 to obtain a slightly corroded surface.

[0071] Step 2: insert the slightly corroded pole 12 into the first through hole 111 of the cover body 11 , and form an insulating member 13 between the cover body 11 and the pole 12 by injection molding.

[0072] In one embodiment, in step 1, degreasing is performed by washing the cover plate body 11 and the pole 12 with a degreasing agent;

[0073] Specifically, the cover body 11 and the pole 12 are clamped and fixed by a clamping device and placed in a cleaning net, and the cover body 11 and the pole 12 are degreased; the degreaser is selected from an organic degreasing solvent, such as gasoline, kerosene, alcohol, trichloroethylene, carbon tetrachloride, Freon and other organic solvents to soak and scrub the cover body 11 and the pole 12, and the grease and impurities on the surface of the cover body 11 and the pole 12 are removed to obtain a cover body 11 and the pole 12 with a clean surface.

[0074] The clamping device is selected from automated clamping tools such as robotic arms, etc., which are easy to operate.

[0075] In one embodiment, the washing process in step 1 includes: placing the cover body 11 and the pole 12 in a clean water tank, washing the cover body 11 and the pole 12 for 5-60 seconds at room temperature, and washing each stage of the washing process at least twice until the pH value of the washing solution reaches 6-8;

[0076] In a preferred embodiment, the cover body 11 and the pole 12 are placed in a clean water tank and washed at least three times in each stage, each time for 30-50 seconds, until the pH value of the washing liquid reaches 6.5-7.5;

[0077] In one embodiment, the alkaline cleaning process of step 1 includes: placing the cover plate body 11 and the terminal 12 in an alkaline cleaning tank, and cleaning the cover plate body 11 and the terminal 12 with 40-100 g / L sodium hydroxide at 40-80° C. for 1-10 minutes;

[0078] In a preferred embodiment, the cover plate body 11 and the pole 12 are placed in an alkaline cleaning tank and cleaned with 60-80 g / L sodium hydroxide at 55-65° C. for 4-7 minutes to perform alkaline corrosion.

[0079] In one embodiment, the pickling process of step 1 includes: placing the cover plate body 11 and the pole 12 in a pickling tank, and cleaning the cover plate body 11 and the pole 12 with a 40-100 g / L sulfuric acid solution at 40-80° C. for 1-10 minutes;

[0080] In a preferred embodiment, the cover plate body 11 and the pole 12 are placed in a pickling tank and cleaned for 4-7 minutes using a 60-80 g / L sulfuric acid solution at 55-65° C. to perform acid etching.

[0081] The electrolytic oxidation process of step 1 includes: electrolyzing the cover body 11 and the pole 12 with a voltage of 10-30V for 1-10 minutes;

[0082] In a preferred embodiment, the cover body 11 and the pole 12 are placed in an electrolytic oxidation tank, and electrolytic oxidation is performed on the cover body 11 and the pole 12 using a voltage of 15-25V for 4-7 minutes; the surfaces of the cover body 11 and the pole 12 are electrolytically oxidized.

[0083] Because the cover body 11 is made of metal and the pole 12 is made of copper or aluminum, after alkaline and acid washing, the surfaces of the cover body 11 and the pole 12 are corroded, reducing their corrosion resistance. By oxidizing the surfaces of the cover body 11 and the pole 12, an oxide film is formed on the surfaces of the cover body 11 and the pole 12, thereby improving the surface corrosion resistance.

[0084] In one embodiment, the nano-treatment process of step 1 includes: placing the cover body 11 and the pole 12 in a sodium hydroxide alkaline solution, wherein the pH value of the sodium hydroxide alkaline solution is in the range of 8-12, at 40-80° C., and the etching time is 1-10 minutes; and the nano-treatment process is performed at least twice;

[0085] In a preferred embodiment, the cover body 11 and the pole 12 are placed in a sodium hydroxide alkaline solution, and the cover body 11 and the pole 12 are cleaned for 4-7 minutes at 55-65° C. using sodium hydroxide with a pH value range of 8-12; and the alkaline corrosion treatment is performed again.

[0086] The baking process of step 1 includes: placing the cover body 11 and the pole 12 in a baking oven, baking at 60-100° C. for 20-60 minutes; and performing the nano-processing process at least twice.

[0087] In a preferred embodiment, the cover body 11 and the pole 12 are placed in a baking oven and baked at 70-90° C. for 30-50 minutes. The baking process is performed 2-5 times, preferably 3 times.

[0088] Specifically, the micro-corrosion process of the present application is as follows: the cover body 11 and the pole 12 are clamped and fixed by a clamping device and placed in a cleaning net, and the cover body 11 and the pole 12 are degreased with alcohol; then the cover body 11 and the pole 12 are placed in a clean water tank and washed 3 times, each time for 40 seconds; the cover body 11 and the pole 12 are placed in an alkaline cleaning tank, and at 60°C, 80g / L of sodium hydroxide is used to clean the cover body 11 and the pole 12 for 5 minutes; then the cover body 11 and the pole 12 are placed in a clean water tank and washed 3 times, each time for 40 seconds; the cover body 11 and the pole 12 are placed in an acid cleaning tank, and at 60°C, 80g / L of sulfuric acid solution is used to clean the cover body 11 and the pole 12 for 5 minutes; then the cover body 11 and the pole 12 are placed in a clean water tank and washed. 3 times, each time for 40 seconds; place the cover body 11 and the pole 12 in an alkaline washing tank, and use 80g / L sodium hydroxide to clean the cover body 11 and the pole 12 for 5 minutes at 60°C; then place the cover body 11 and the pole 12 in a clean water tank and clean them 3 times, each time for 40 seconds; place the cover body 11 and the pole 12 in an electrolytic oxidation tank, and use a voltage of 20V for electrolytic oxidation for 5 minutes; then place the cover body 11 and the pole 12 in a clean water tank and clean them 3 times, each time for 40 seconds; place the cover body 11 and the pole 12 in a sodium hydroxide alkaline solution for nano-treatment for 5 minutes; then place the cover body 11 and the pole 12 in a clean water tank and clean them 3 times, each time for 40 seconds; place the cover body 11 and the pole 12 in a baking oven, bake at 80°C for 40 minutes, and bake 3 times.

[0089] After the micro-etching treatment is completed, micropores are formed on the surface of the cover body 11 and the pole 12. When the cover body 11 and the pole 12 are made of copper, the pore diameter of the micropores is 50-300nm; when the cover body 11 and the pole 12 are made of aluminum, the pore diameter of the micropores is 10-100nm.

[0090] In step 3, the slightly corroded pole 12 is inserted into the first through hole 111 of the cover body 11, and an insulating member 13 is formed between the cover body 11 and the pole 12 by injection molding. The insulating member 13 includes a first insulating member 131, a second insulating member 132, and a third insulating member 133.

[0091] High pressure is used to inject molding into the gap between the outer side of the pole 12 and the inner side of the first through hole 111 to form the second insulating member 132; injection molding is performed on the outside of the first end of the pole 12 protruding from the first through hole 111 and covering the surface of the first end of the cover body 11 to form the first insulating member 131; injection molding is performed on the outside of the second end of the pole 12 protruding from the first through hole 111 and covering the surface of the second end of the cover body 11 to form the third insulating member 133; the first insulating member 131, the second insulating member 132 and the third insulating member 133 are all annular structures, and the first insulating member 131, the second insulating member 132 and the third insulating member 133 are integrally formed, and the first insulating member 131 and the third insulating member 133 are respectively located at both ends of the second insulating member 132. After high-pressure injection molding, the insulating part 13 is filled in the micropores and is strongly combined with the pole 12 and the cover body 11, thereby meeting the sealing and strength requirements between the pole 12 and the cover body 11. The injection molding process of the insulating part 13 can not only achieve the purpose of insulation, but also solve the sealing problem at the same time, so that there is no need to set a sealing ring on the battery cover 1, the structure is simple, the number of components is small, and the processing process is simple.

[0092] Compared with the prior art, the battery cover 1 provided in this application has the following main effects:

[0093] (1) The present application provides an insulating member 13 in the first through hole 111 to isolate the pole 12 from the cover body 11, thereby preventing the pole 12 from contacting the cover body 11 and achieving a technical insulation effect on the pole 12 and the cover body 11;

[0094] (2) The insulating member 13 of the present application is filled between the pole 12 and the cover body 11 by injection molding, connecting the pole 12 and the cover body 11 into a whole, preventing the pole 12 from twisting relative to the cover body 11 during use, and reducing the related anti-twist structure;

[0095] (3) In the present application, a plurality of first micropores 112 are formed on the inner wall of the first through hole 111, and a plurality of second micropores 122 are formed on the outer wall of the pole 12. The insulating member 13 is filled between the pole 12 and the cover body 11 by injection molding, and penetrates into the first micropores 112 and the second micropores 122, thereby improving the connection strength between the pole 12 and the cover body 11, and connecting the pole 12 and the cover body 11 into a whole.

[0096] (4) The setting of the insulating member 13 of the present application not only plays the technical effect of isolating the pole 12 and the cover body 11, but also connects the pole 12 and the cover body 11 into a whole, playing the technical effect of the anti-torsion structure. Therefore, the setting of the insulating member 13 of the present application reduces the use of the insulating member 13 and / or the anti-torsion structure, making the structure of the battery cover 1 of the present application simple, using fewer parts, and at the same time, the processing method is simple, the processing cost is low, and the parts and related processing process are saved, and the use effect is good;

[0097] (5) The extended structure on both sides of the cover body 11 can be sealed and fitted with the battery housing 3 by welding, thereby ensuring the sealing and safety of the battery 100, thereby improving the safe use performance of the battery cover 1.

[0098] As shown in Figures 7-9, the third aspect of the present application provides a battery 100, including a pole core assembly 2, at least two battery cover plates 1 as described above, and a metal shell assembly, the pole core assembly 2 is connected to the battery cover plate 1, the metal shell assembly includes a first metal shell 31 and a second metal shell 32, the first metal shell 31 and the second metal shell 32 are sealed and connected, the first metal shell 31 and the second metal shell 32 are both provided with a receiving groove 34 and a welding skirt 33, the two receiving grooves 34 are arranged relative to each other to form a receiving cavity for receiving the pole core assembly 2, the welding skirt 33 is arranged on the outer periphery of the open end of the receiving groove 34, and the welding skirt 33 extends from the open end of the receiving groove 34 in a direction away from the receiving groove 34, and the two welding skirts 33 are sealed and welded; the battery cover plate 1 is welded between the two welding skirts 33.

[0099] It can be understood that the battery 100 provided in the present application includes at least two battery cover plates 1, the battery cover plate 1 contains a pole 12, the pole core assembly 2 contains a pole ear 21, and the pole ear 21 is connected to the pole 12 by welding to realize the connection between the pole core assembly 2 and the battery cover plate 1.

[0100] Specifically, the two receiving grooves 34 are defined as a first receiving groove 34 and a second receiving groove 34, and the two welding skirts 33 are defined as a first welding skirt 33 and a second welding skirt 33. The first metal shell 31 is provided with the first receiving groove 34 and the first welding skirt 33, and the second metal shell 32 is provided with the second receiving groove 34 and the second welding skirt 33. The first welding skirt 33 is provided at the periphery of the open end of the first receiving groove 34 and extends from the open end of the first receiving groove 34 in a direction away from the first receiving groove 34. The second welding skirt 33 is provided at the periphery of the open end of the second receiving groove 34 and extends from the open end of the second receiving groove 34 in a direction away from the second receiving groove 34.

[0101] The first accommodating groove 34 and the second accommodating groove 34 are arranged opposite to each other, and can form an accommodating cavity for accommodating the pole core assembly 2 .

[0102] Specifically, the first welding skirt 33 and the second welding skirt 33 are welded together by laser welding, electromagnetic pulse welding, resistance welding, electron beam welding, etc., so that the first metal shell 31 and the second metal shell 32 are sealed and connected.

[0103] The first and second metal shells 31, 32 are made of metal, preferably a lightweight, high-strength metal such as aluminum or stainless steel. The first welding skirt 33 is also made of metal, preferably the same material as the first metal shell 31. The second welding skirt 33 is also made of metal, preferably the same material as the second metal shell 32. Since the first and second welding skirts 33, 33, are made of metal, they can be welded together to achieve a sealed connection between the first and second metal shells 31, 32.

[0104] Compared to using a plastic shell, the battery 100 can only be sealed by hot melting the two plastic shells, which has poor sealing performance and affects the performance of the battery 100. The shell of the present application is made of metal, and the first metal shell 31 and the second metal shell 32 are sealed and welded by laser welding, electromagnetic pulse welding, resistance welding, electron beam welding, etc., which can improve the sealing performance of the battery 100 and increase the cycle life of the battery 100, while ensuring that the battery 100 has high strength.

[0105] As shown in Figures 8-10, the side of the first welding skirt 33 facing the second metal shell 32 is seal-welded to the side of the battery cover 1 facing the first welding skirt 33, and the side of the second welding skirt 33 facing the first metal shell 31 is seal-welded to the side of the battery cover 1 facing the second welding skirt 33. Compared to the prior art, the battery cover 1 is welded between the first welding skirt 33 and the second welding skirt 33, achieving a sealed connection between the battery cover 1 and the first and second welding skirts 33, thereby improving the sealing performance of the battery 100.

[0106] It should be noted that the sealing welding method in this application includes laser welding, electromagnetic pulse welding, resistance welding, electron beam welding and other welding methods.

[0107] As shown in FIG. 10 , in one embodiment, the fourth aspect of the present application provides a method for processing a single battery 100 , comprising the following steps S10 - S70 .

[0108] S10. Prepare a pole core assembly 2, two battery cover plates 1, a first metal shell 31 and a second metal shell 32. The two battery cover plates 1 are respectively a positive pole cover plate 15 and a negative pole cover plate 16. The first end of the pole core assembly 2 is a positive pole ear 211, and the second end of the pole core assembly 2 is a negative pole ear 212.

[0109] It can be understood that the battery 100 monomer is composed of a core assembly 2, an electrolyte, two battery covers 1, and two metal shells, wherein the core assembly 2 is a bare cell formed by pole pieces, and the two battery covers 1 and the two metal shells can enclose a storage space for accommodating the core assembly 2 and the electrolyte. The two battery covers 1 are respectively the positive electrode cover 15 and the negative electrode cover 16, and the two metal shells are respectively the first metal shell 31 and the second metal shell 32 with a cavity. The positive tab 211 and the negative tab 212 are the protruding parts at both ends of the core assembly 2. The battery 100 monomer is charged and discharged through the core assembly 2, which includes multiple layers of positive electrode sheets, negative electrode sheets, and diaphragms. The positive electrode sheets, diaphragms, negative electrode sheets, diaphragms... are made into a battery 100 core in a top-down order. According to the number of pole cores of the battery 100, the battery 100 can be divided into a single-pole core battery 100 and a multi-pole core battery 100. The pole core assembly 2 of the single-pole core battery 100 refers to a single pole core, and the pole core assembly 2 of the multi-pole core battery 100 refers to a combined pole core formed by multiple pole cores. The battery 100 has positive and negative poles, and the pole tabs 21 are metal conductors extending from the positive and negative poles, serving as contact points during charging and discharging. The first end of the pole core assembly 2 refers to the positive pole, and the second end refers to the negative pole. The first end can be the left end or the right end. For each pole piece, each positive pole piece is reserved with a positive pole piece tab 21, and each negative pole piece is reserved with a negative pole piece tab 21. The pole core assembly 2 includes multiple layers of positive pole pieces and negative pole pieces. The multiple layers of positive pole piece tabs 21 are pre-welded together to form the positive pole tab 211 of the pole core assembly 2, and the multiple layers of negative pole piece tabs 21 are pre-welded together to form the negative pole tab 212 of the pole core assembly 2.

[0110] S20 , welding the positive electrode tab 211 and the positive electrode cover plate 15 , and welding the negative electrode tab 212 and the negative electrode cover plate 16 to obtain a first assembly.

[0111] It can be understood that the first component is the core battery cover plate 1 consisting of the core assembly 2, the positive electrode cover plate 15, and the negative electrode cover plate 16. In this embodiment, the connection between the positive electrode tab 211 and the positive electrode cover plate 15, and the connection between the negative electrode tab 212 and the negative electrode cover plate 16 can be achieved by welding. The welding method can be laser welding or ultrasonic welding. During welding, the positive electrode tab 211 and the positive electrode cover plate 15 can be welded first, or the negative electrode tab 212 and the negative electrode cover plate 16 can be welded first. It is also possible to weld the positive electrode tab 211 and the positive electrode cover plate 15, and the negative electrode tab 212 and the negative electrode cover plate 16 at the same time.

[0112] S30 , coating the first component with an insulating film 22 .

[0113] It is understandable that before the core assembly 2 of the battery 100 is installed in the metal shell, an insulating film 22 needs to be coated on the outside of the core assembly 2 to achieve insulation between the core assembly 2 and the battery shell 3. The insulating film 22 is a film obtained by pre-forming an insulating material to adapt to the contour of the core assembly 2. The insulating material of the insulating film 22 can be polypropylene (PP) or polyethylene terephthalate (PET). At the same time, since the metal shell has internal corners during molding, coating the core assembly 2 with the insulating film 22 can also prevent mechanical damage caused by squeezing, shaking or friction between the internal corners of the core assembly 2 and the metal shell, thereby protecting the performance and safety of the battery 100.

[0114] S40. The first component covered with the insulating film 22 is installed in the accommodating space formed by the first metal shell 31 and the second metal shell 32 to obtain a second component; the accommodating space has a first opening and a second opening arranged opposite to each other; the positive electrode cover plate 15 is installed in the first opening, and the negative electrode cover plate 16 is installed in the second opening.

[0115] It can be understood that the second component is a pole core cover plate shell assembly consisting of a pole core battery cover plate 1 and a first metal shell 31 and a second metal shell 32. According to the different packaging forms, the battery 100 monomer can be divided into a hard shell battery 100 monomer and a soft shell battery 100 monomer. The hard shell battery 100 monomer uses a metal shell as the outer shell, such as a steel shell or an aluminum shell, and the soft shell battery 100 monomer uses an aluminum-plastic film as the outer shell. The battery 100 monomer of this embodiment is a square hard shell battery 100 monomer or a cylindrical hard shell battery 100 monomer, wherein the two battery cover plates 1 and the two metal shells can form a rectangular or cylindrical cavity for accommodating the pole core assembly 2 and the electrolyte. In this embodiment, the metal shell is divided into two parts, a first metal shell 31 and a second metal shell 32. The first metal shell 31 and the second metal shell 32 both have an open groove 123, which is used to form a specific shape of the accommodation space by covering. When the battery 100 cell is a square hard-shell battery 100 cell, the cross-section of the first metal shell 31 and the second metal shell 32 in the thickness direction is a semi-rectangular groove 123; when the battery 100 cell is a cylindrical hard-shell battery 100 cell, the cross-section of the first metal shell 31 and the second metal shell 32 in the thickness direction is a semicircular groove 123.

[0116] In this embodiment, the core battery cover plate 1 coated with the insulating film 22 is placed in the first metal shell 31, and the second metal shell 32 is then covered on the first metal shell 31, so that the core assembly 2 is located in the accommodation space formed by the first metal shell 31 and the second metal shell 32, thereby obtaining the core cover plate housing assembly. In addition, because the positive electrode cover plate 15 and the negative electrode cover plate 16 have been welded to the core assembly 2, the accommodation space formed by the first metal shell 31 and the second metal shell 32 has a first opening and a second opening arranged opposite each other, so that the positive electrode cover plate 15 is installed in the first opening and the negative electrode cover plate 16 is installed in the second opening.

[0117] S50. The second component is shaped by the shaping mold 5 so that the first metal shell 31 and the second metal shell 32 are bonded to each other, the positive electrode cover plate 15 is bonded to the first metal shell 31 and the second metal shell 32, and the negative electrode cover plate 16 is bonded to the first metal shell 31 and the second metal shell 32.

[0118] As can be understood, the first metal shell 31 and the second metal shell 32 include a main cavity and a welded skirt 33 surrounding the main cavity. The main cavity is a central groove 123 for accommodating the electrode core assembly 2 and the electrolyte, and the welded skirt 33 is an extension 122 surrounding the main cavity. As the welded joint between the first metal shell 31 and the second metal shell 32, between the first metal shell 31 and the positive and negative electrode covers 15 and 16, and between the second metal shell 32 and the positive and negative electrode covers 15 and 16, the welded skirt 33 also forms a welded skirt 33 groove that adapts to the positive and negative electrode covers 15 and 16. The positive electrode cover 15 has opposite front and back surfaces in the thickness direction, and the negative electrode cover 16 has opposite front and back surfaces in the thickness direction. The front surface can refer to either the upper or lower half. When the first metal shell 31 and the second metal shell 32 are covered, the welding skirts 33 of the first metal shell 31 and the second metal shell 32 overlap each other, and the grooves of the welding skirts 33 of the first metal shell 31 and the second metal shell 32 cover the front and back surfaces of the positive electrode cover plate 15 and the negative electrode cover plate 16. Because there may be gaps or shape mismatches, it is necessary to use a shaping mold 5 to shape the two metal shells of the core cover plate housing assembly so that the welding skirts 33 of the first metal shell 31 and the second metal shell 32 fit together, the grooves of the welding skirts 33 of the first metal shell 31 and the second metal shell 32 fit together with the front and back surfaces of the positive electrode cover plate 15, and the grooves of the welding skirts 33 of the first metal shell 31 and the second metal shell 32 fit together with the front and back surfaces of the negative electrode cover plate 16.

[0119] S60: performing sealing welding on the reshaped second component to seal the accommodating space.

[0120] Understandably, the reshaped pole core cover plate shell assembly has a flat surface, and a good sealing effect can be achieved by welding. The sealing welding method can be one of resistance welding, electron beam welding, electromagnetic pulse welding and laser welding. The welding operation is performed on the welding skirt 33 of the reshaped pole core cover plate shell assembly, so that the first metal shell 31 and the second metal shell 32, the first metal shell 31 and the positive electrode cover plate 15, the negative electrode cover plate 16, and the second metal shell 32 and the positive electrode cover plate 15, the negative electrode cover plate 16 are connected into a whole by welds to form a sealed accommodating space.

[0121] S70 , performing post-processing on the sealed second assembly to obtain a battery 100 single body.

[0122] Understandably, post-processing includes airtightness testing, baking, liquid injection, formation, and volume separation. In this embodiment, the sealed core cover plate housing assembly is sequentially subjected to airtightness testing, baking, liquid injection, formation, and volume separation to obtain a battery cell 100.

[0123] In this embodiment, the first assembly is formed by welding the tab 21 of the core assembly 2 to the battery cover 1. The first assembly is then placed into the cavity of an open two-part metal shell, and the two parts of the metal shell are closed to form a housing space to form the second assembly. On the one hand, this embodiment utilizes a metal shell with an open cavity, eliminating special requirements for the shell opening during production. This allows for a thinner metal shell while maintaining rigidity and structural strength, saving manpower and material resources, reducing the cost and difficulty of manufacturing the metal shell, and facilitating improved heat dissipation performance of the battery 100. On the other hand, this embodiment directly places the first assembly into the open two-part metal shell during casing, allowing for direct determination of the assembly position of the core assembly 2 and the battery cover 1. This eliminates the need for folding the tab 21 and pressing the cover, reducing assembly difficulty and simplifying the process. Furthermore, unlike a multiple-push casing method, this embodiment avoids assembly damage, improving product quality and processing efficiency. Finally, the battery cell processing method of this embodiment ensures a tighter fit between the metal shell and the cover plate by first shaping the second component, and then performing a sealing process to seal the accommodation space, thereby ensuring a good sealing effect. This battery cell processing method of this embodiment allows for the assembly of thicker pole core assemblies 2 with thinner metal shells, which is beneficial for improving the assembly ratio. It also enables negative pressure sealing of the battery cell 100, ensuring good contact between the pole pieces within the battery cell 100, and improving the stability of the battery 100, thereby ensuring the service life of the battery 100.

[0124] In one embodiment, step S20, that is, welding the positive electrode tab 211 and the positive electrode cover plate 15, and welding the negative electrode tab 212 and the negative electrode cover plate 16, includes:

[0125] S201, welding the positive electrode tab 211 and the inner lead-out tab of the positive electrode cover plate 15 according to preset welding parameters to form a positive electrode weld 41;

[0126] S202, welding the negative electrode tab 212 and the inner lead-out tab of the negative electrode cover plate 16 according to preset welding parameters to form a negative electrode weld 42;

[0127] S203 , performing glue application on the positive electrode weld 41 and the negative electrode weld 42 .

[0128] Understandably, the preset welding parameters are pre-set control parameters for welding between the positive electrode tab 211 and the positive electrode cover plate 15, and between the negative electrode tab 212 and the negative electrode cover plate 16, including welding starting point position parameters, welding direction parameters, and welding length parameters. Both the positive electrode cover plate 15 and the negative electrode cover plate 16 are provided with inner lead tabs, which allow the positive electrode tab 211 and the positive electrode cover plate 15 to be welded together, and the negative electrode tab 212 and the negative electrode cover plate 16 to be welded together.

[0129] As shown in FIG13 , in this embodiment, the left end of the electrode core assembly 2 is a positive electrode tab 211, and the right end of the electrode core assembly 2 is a negative electrode tab 212. The positive electrode tab 211 is welded to the inner lead tab of the positive electrode cover 15 according to preset welding parameters to form a positive electrode weld 41; and the negative electrode tab 212 is welded to the inner lead tab of the negative electrode cover 16 according to preset welding parameters to form a negative electrode weld 42. After welding is completed, the surfaces of the positive electrode weld 41 and the negative electrode weld 42 are coated with glue to prevent burrs on the weld from splashing or welding slag from falling off and damaging the electrode core assembly 2.

[0130] In this embodiment, the inner lead tab of the positive electrode cover plate 15 is connected to the positive electrode tab 211 via the positive electrode weld 41, and the inner lead tab of the negative electrode cover plate 16 is connected to the negative electrode tab 212 via the negative electrode weld 42. This allows for accurate positioning of the welds and ensures welding accuracy. Furthermore, applying glue to the positive electrode weld 41 and the negative electrode weld 42 effectively prevents damage to the electrode core assembly 2.

[0131] In one embodiment, step S40, that is, placing the first component covered with the insulating film 22 into the accommodation space formed by the first metal shell 31 and the second metal shell 32, includes:

[0132] S401. After the first metal shell 31 is covered on the front of the first component, the first component covered with the first metal shell 31 is turned over, and the second metal shell 32 is covered on the back of the first component, so that the first metal shell 31 and the second metal shell 32 are covered to form an accommodating space.

[0133] It can be understood that the first component is the pole core battery cover plate 1 composed of the pole core component 2, the positive electrode cover plate 15 and the negative electrode cover plate 16. The pole core component 2 has relative front and back sides in the thickness direction. The front side of the pole core component 2 can refer to the upper half or the lower half.

[0134] As shown in Figure 7, in this embodiment, the left end of the pole core assembly 2 is connected to the negative electrode cover plate 16, and the right end of the pole core assembly 2 is connected to the positive electrode cover plate 15. The surface of the pole core assembly 2 is wrapped with an insulating film 22. The upper half of the pole core assembly 2 is designated as the front side, and the lower half of the pole core assembly 2 is designated as the back side. When the front side of the pole core assembly 2 with the insulating film 22 wrapped on the surface faces upward, the first metal shell 31 is placed on the pole core assembly 2. Then, the pole core assembly 2 with the insulating film 22 wrapped on the surface and the first metal shell 31 are turned over, and when the back side of the pole core assembly 2 with the insulating film 22 wrapped on the surface faces upward, the second metal shell 32 is placed on the pole core assembly 2. When the first metal shell 31 and the second metal shell 32 are covered, a space is formed for accommodating the pole core assembly 2 with the insulating film 22 wrapped on the surface, the positive electrode cover plate 15, and the negative electrode cover plate 16.

[0135] In this embodiment, the pole core battery cover 1 is placed in two parts of the metal shell in an open state, and the two parts of the metal shell are covered to form an accommodating space to obtain a pole core cover shell assembly. There is no need to use multiple pushes to cover the shell, which avoids damage, simplifies the operation process, and improves processing efficiency.

[0136] In one embodiment, step S50, i.e., shaping the second component by the shaping mold 5, includes:

[0137] S501, loading the second component into the shaping mold 5;

[0138] S502. The first metal shell 31 and the second metal shell 32 are pressed and shaped by the shaping mold 5 so that the welding skirt 33 of the first metal shell 31 and the welding skirt 33 of the second metal shell 32, the positive electrode cover plate 15 and the edge shell of the first opening, and the negative electrode cover plate 16 and the edge shell of the second opening are in contact with each other.

[0139] Understandably, the second component is the core battery cover plate housing assembly consisting of the core battery cover plate 1, the first metal shell 31, and the second metal shell 32. The shaping mold 5 is a hollow mold pre-made according to standard dimensions to adapt to the contour of the core battery cover plate housing assembly. The shaping mold 5 includes two openable and closable parts for loading the core battery cover plate housing assembly to be shaped.

[0140] As shown in Figure 12, in this embodiment, the pole core cover plate shell assembly is loaded into the shaping mold 5 for press-fit shaping. Through the deformation of the first metal shell 31 and the second metal shell 32, the positive pole cover plate 15 and the edge shell of the first opening formed by the welding skirt 33 groove of the first metal shell 31 and the welding skirt 33 groove of the second metal shell 32, the negative pole cover plate 16 and the edge shell of the second opening formed by the welding skirt 33 groove of the first metal shell 31 and the welding skirt 33 groove of the second metal shell 32, and the first metal shell 31 and the welding skirt 33 of the second metal shell 32 are fit together to obtain the shaped pole core cover plate shell assembly.

[0141] In this embodiment, the pole core cover plate shell assembly is pressed and shaped by a standard shaping mold 5, thereby reducing the gap between the two metal shells and the two cover plates and ensuring the degree of fit between the metal shells and the cover plates.

[0142] In one embodiment, step S60, namely, performing sealing welding on the shaped second component to seal the accommodating space, further includes:

[0143] S601, sealingly welding the front surface of the second component according to first preset sealing parameters to form a first sealing weld 61 surrounding the accommodating space, thereby sealing the assembly gaps between the welding skirt 33 of the first metal shell 31 and the welding skirt 33 of the second metal shell 32, between the front surface of the positive electrode cover plate 15 and the first metal shell 31 corresponding to the first opening, and between the front surface of the negative electrode cover plate 16 and the first metal shell 31 corresponding to the second opening;

[0144] S602. The reverse side of the electrode core cover plate shell assembly is sealed and welded according to the second preset sealing parameters, and a second sealing weld 62 is formed at the position corresponding to the positive electrode cover plate 15 and the negative electrode cover plate 16 to seal the assembly gap between the reverse side of the positive electrode cover plate 15 and the second metal shell 32 corresponding to the first opening, and between the reverse side of the negative electrode cover plate 16 and the second metal shell 32 corresponding to the second opening.

[0145] Understandably, the first preset sealing parameters are control parameters pre-set for surrounding welding on the front side of the pole core cover plate shell assembly. The second preset sealing parameters are control parameters pre-set for welding on the back side of the pole core cover plate shell assembly. The second assembly is a pole core cover plate shell assembly consisting of the pole core battery cover plate 1 and the first metal shell 31 and the second metal shell 32. The pole core battery cover plate 1 has relative front and back sides in the thickness direction. The front side of the pole core battery cover plate 1 can refer to the upper half or the lower half. The outermost layer of the pole core cover plate shell assembly is the outer surface formed by the first metal shell 31, the second metal shell 32, the positive electrode cover plate 15 and the negative electrode cover plate 16. The front and back sides of the pole core cover plate shell assembly refer to one of the outer surface of the first metal shell 31 and the outer surface of the second metal shell 32. When the outer surface of the first metal shell 31 is the front side of the pole core cover plate shell assembly, the outer surface of the second metal shell 32 is the back side of the pole core cover plate shell assembly; when the outer surface of the second metal shell 32 is the front side of the pole core cover plate shell assembly, the outer surface of the first metal shell 31 is the back side of the pole core cover plate shell assembly.

[0146] As shown in Figures 13 and 14, in this embodiment, the front side of the core cover plate housing assembly is the outer surface of the first metal housing 31, and the back side of the core cover plate housing assembly is the outer surface of the second metal housing 32. A single seal weld is performed on the outer surface of the welding skirt 33 of the first metal housing 31 according to first preset sealing parameters, forming a first sealing weld 61 surrounding the accommodating space. This ensures that the assembly gaps between the welding skirt 33 of the first metal housing 31 and the welding skirt 33 of the second metal housing 32, between the groove of the welding skirt 33 of the first metal housing 31 and the positive electrode cover 15, and between the groove of the welding skirt 33 of the first metal housing 31 and the negative electrode cover 16 are aligned, and the connection is sealed by the first sealing weld 61. At this point, the welding skirt 33 of the second metal housing 32 on the back side of the core cover plate housing assembly is connected to the welding skirt 33 of the first metal housing 31, but the groove of the welding skirt 33 of the second metal housing 32 is not connected to the positive electrode cover 15 and the negative electrode cover 16. The outer surface of the welding skirt 33 of the second metal shell 32 is sealed and welded for the second time according to the second preset sealing parameters, and a second sealing weld 62 is formed at the position corresponding to the positive cover plate 15 and the negative cover plate 16, so that the assembly gaps between the groove of the welding skirt 33 of the second metal shell 32 and the positive cover plate 15 and between the groove of the welding skirt 33 of the second metal shell 32 and the negative cover plate 16 are fit together, and the connection seal is achieved through the second sealing weld 62.

[0147] The first sealing welds 61 are four welds that surround the accommodating space and are connected end to end. The upper and lower first sealing welds 61 are used to connect the welding skirt 33 of the first metal shell 31 to the welding skirt 33 of the second metal shell 32. The first sealing weld 61 on the left is used to connect the groove of the welding skirt 33 of the first metal shell 31 to the positive electrode cover 15. The first sealing weld 61 on the right is used to connect the groove of the welding skirt 33 of the first metal shell 31 to the negative electrode cover 16. The second sealing welds 62 are two groups of "two horizontal and one vertical" welds, distributed along the groove of the welding skirt 33 of the second metal shell 32. The two horizontal welds in each group are parallel to each other and perpendicular to the vertical weld. The vertical welds in the group of second sealing welds 62 on the left are distributed along the length of the positive electrode cover plate 15, and are used to achieve the connection between the groove of the welding skirt 33 of the second metal shell 32 and the positive electrode cover plate 15. The transverse welds are distributed along the width of the positive electrode cover plate 15, and are used to strengthen the connection between the groove of the welding skirt 33 of the second metal shell 32 and the positive electrode cover plate 15. The vertical welds in the group of second sealing welds 62 on the right are distributed along the length of the negative electrode cover plate 16, and are used to achieve the connection between the groove of the welding skirt 33 of the second metal shell 32 and the negative electrode cover plate 16. The transverse welds are distributed along the width of the negative electrode cover plate 16, and are used to strengthen the connection between the groove of the welding skirt 33 of the second metal shell 32 and the negative electrode cover plate 16.

[0148] In this embodiment, a sealing welding is performed once on the front side of the pole core cover plate shell assembly, and a second sealing welding is performed on the back side of the pole core cover plate shell assembly. Through the complementary effect of the two sealing weldings, a sealed accommodating space is formed between the first metal shell 31, the second metal shell 32, the positive electrode cover plate 15 and the negative electrode cover plate 16, thereby improving the welding processing efficiency while ensuring the sealing effect.

[0149] In one embodiment, step S10, i.e., preparing the first metal shell 31 and the second metal shell 32, includes:

[0150] S103. Stamp the metal sheet according to preset stamping parameters to obtain a first metal shell 31 having a first cavity and a second metal shell 32 having a second cavity adapted to the first cavity; wherein, when the first metal shell 31 and the second metal shell 32 are covered, the first cavity and the second cavity are connected and enclose a accommodating space.

[0151] It is understandable that the metal shell is formed by stamping a metal sheet. The preset stamping parameters are pre-set operating parameters for stamping the metal sheet, including stamping depth, stamping angle, and stamping angle. The first metal shell 31 and the second metal shell 32 include a main cavity and a welding skirt 33 surrounding the main cavity. The main cavity is a middle groove 123 for accommodating the electrode core assembly 2 and the electrolyte. The welding skirt 33 is an extension 122 surrounding the main cavity, serving as a welding joint between the first metal shell 31 and the second metal shell 32, between the first metal shell 31 and the positive electrode cover plate 15 and the negative electrode cover plate 16, and between the second metal shell 32 and the positive electrode cover plate 15 and the negative electrode cover plate 16. The welding skirt 33 also includes a welding skirt 33 groove adapted to the positive electrode cover plate 15 and the negative electrode cover plate 16.

[0152] In this embodiment, the pole core assembly 2, the positive electrode cover plate 15 and the negative electrode cover plate 16 have relative front and back surfaces in the thickness direction. The metal sheet is stamped according to preset stamping parameters to form a cavity groove 123 on the metal sheet for accommodating the front surface of the pole core assembly 2 and a welding skirt 33 groove on the front surface for accommodating the positive electrode cover plate 15 and the negative electrode cover plate 16, thereby obtaining a first metal shell 31; the metal sheet is stamped according to preset stamping parameters to form a cavity groove 123 on the metal sheet for accommodating the back surface of the pole core assembly 2 and a welding skirt 33 groove on the back surface for accommodating the positive electrode cover plate 15 and the negative electrode cover plate 16, thereby obtaining a second metal shell 32.

[0153] This embodiment has no special requirements for the shell opening of the metal shell. It is formed in one step by stamping the metal sheet, which reduces the production cost and difficulty of the metal shell. At the same time, the assembly position of the pole core assembly 2 and the cover plate can be directly determined by the groove 123 of the metal shell, which reduces the assembly difficulty.

[0154] In one embodiment, a liquid injection hole 14 is provided on the positive electrode cover plate 15 or the negative electrode cover plate 16; step S701, that is, injecting liquid into the sealed second component, includes:

[0155] S7011, injecting electrolyte into the accommodation space of the baked second component through the injection hole 14, and temporarily sealing the injection hole 14;

[0156] The sealed second component is formed, including:

[0157] S7012, after performing a chemical conversion treatment on the second component after the temporary sealing treatment, the liquid injection hole 14 is permanently sealed.

[0158] Understandably, injection is divided into primary injection and secondary injection. The primary injection is the first injection, and the secondary injection is the process of replenishing the electrolyte after formation. The injection hole 14 can be set on the positive cover plate 15 or on the negative cover plate 16. The injection hole 14 is used to allow the electrolyte to enter the accommodating space of the pole core cover plate shell assembly. After the primary injection, the injection hole 14 is temporarily sealed. The temporary sealing treatment can be done by blocking the injection hole 14 with a rubber nail. After the formation test, if secondary injection is not required, the injection hole 14 is directly permanently sealed; if secondary injection is required, the injection hole 14 is permanently sealed after the secondary injection. The permanent sealing treatment can be done by welding metal sheets.

[0159] In this embodiment, the injection hole 14 is temporarily sealed after one injection to prevent leakage of electrolyte while facilitating the addition of electrolyte. After the formation test, the injection hole 14 is permanently sealed to prevent leakage of electrolyte and ensure the stability of the battery 100.

[0160] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0161] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A battery cover, wherein: The battery cover is used to close the battery shell to form a battery. The battery cover includes a cover body, a pole and an insulating member. The cover body is provided with a first through hole, the inner wall of the first through hole is formed with a plurality of first micropores, the outer wall of the pole is formed with a plurality of second micropores, the insulating member is arranged between the pole and the cover body, and the insulating member at least partially invades the first micropores and the second micropores.

2. The battery cover according to claim 1, wherein: The insulating member includes a first insulating member, a second insulating member and a third insulating member, the first insulating member, the second insulating member and the third insulating member are all annular structures, the first insulating member, the second insulating member and the third insulating member are integrally formed, the first insulating member and the third insulating member are respectively located at both ends of the second insulating member, and the outer diameters of the first insulating member and the third insulating member are both greater than the outer diameter of the second insulating member.

3. The battery cover according to claim 2, wherein: A plurality of third micropores are formed on the surface of the first end of the cover body, a plurality of fourth micropores are formed on the surface of the second end of the cover body, the first insulating member at least partially invades the first micropores and the third micropores located outside the first end of the first through hole, the second insulating member at least partially invades the first micropores and the second micropores, the third insulating member at least partially invades the first micropores and the fourth micropores located outside the second end of the first through hole, and the pore diameters of the first micropores, the second micropores, the third micropores and the fourth micropores are 50-300nm.

4. The battery cover according to claim 1, wherein: The cover plate body is provided with a liquid injection hole, and the liquid injection hole is connected to the interior of the battery shell.

5. The battery cover according to claim 4, wherein: It also includes a sealing plug, which is selected from a conical sealing plug and a spherical sealing plug. The conical sealing plug or the spherical sealing plug is embedded in the injection hole to seal the injection hole.

6. A method for preparing a battery cover: wherein: The method for preparing the battery cover according to any one of claims 1 to 5 comprises the following steps: Step 1, sequentially subjecting the cover plate body and the pole to degreasing, water washing, alkali washing, water washing, acid washing, water washing, alkali washing, water washing, electrolytic oxidation, water washing, nano-treatment, water washing, and drying to obtain the cover plate body and the pole with slightly corroded surfaces; Step 2: insert the slightly corroded pole into the first through hole of the cover body, and form the insulating member between the cover body and the pole by injection molding.

7. The method for preparing a battery cover according to claim 6, wherein: In the step 1, degreasing is performed by washing the cover plate body and the pole with a degreasing agent; The washing process in step 1 comprises: placing the cover body and the pole in a clean water tank, washing the cover body and the pole for 5-60 seconds at room temperature, washing at least twice in each stage of the washing process until the pH value of the washing liquid is 6-8; The alkali washing process of step 1 comprises: placing the cover plate body and the pole in an alkali washing tank, and washing the cover plate body and the pole with 40-100 g / L sodium hydroxide at 40-80° C. for 1-10 min; The pickling process of step 1 comprises: placing the cover plate body and the pole in a pickling tank, and cleaning the cover plate body and the pole with a 40-100 g / L sulfuric acid solution at 40-80° C. for 1-10 min; The electrolytic oxidation process of step 1 includes: electrolyzing the cover body and the pole using a voltage of 10-30V. The time is 1-10min; The nano-treatment process of step 1 comprises: placing the cover plate body and the pole in a sodium hydroxide alkaline solution, wherein the pH value of the sodium hydroxide alkaline solution is in the range of 8-12, at 40-80° C., and the corrosion time is 1-10 minutes; and the nano-treatment process is performed at least twice; The baking process of step 1 includes: placing the cover plate body and the pole in a baking oven, baking at 60-100° C. for 20-60 minutes; and performing the nano-treatment process at least twice.

8. A battery, wherein: It includes a pole core assembly, at least two battery cover plates as described in any one of claims 1 to 5, and a metal shell assembly, wherein the pole core assembly is connected to the battery cover plate, and the metal shell assembly includes a first metal shell and a second metal shell, the first metal shell and the second metal shell are sealed and connected, and the first metal shell and the second metal shell are both provided with a receiving groove and a welding skirt, the two receiving grooves are relatively arranged to form a receiving cavity for receiving the pole core assembly, the welding skirt is arranged on the outer periphery of the open end of the receiving groove, and the welding skirt extends from the open end of the receiving groove in a direction away from the receiving groove, and the two welding skirts are sealed and welded; the battery cover plate is welded between the two welding skirts.

9. A method for processing a battery as claimed in claim 8, wherein: include: Prepare the pole core assembly, the two battery cover plates, the first metal shell and the second metal shell, the two battery cover plates are respectively a positive electrode cover plate and a negative electrode cover plate, the first end of the pole core assembly is a positive electrode ear, and the second end of the pole core assembly is a negative electrode ear; Welding the positive electrode tab and the positive electrode cover plate, and welding the negative electrode tab and the negative electrode cover plate to obtain a first assembly; Coating an insulating film on the first component; The first component coated with the insulating film is installed in a housing space formed by the first metal shell and the second metal shell to obtain a second component; the housing space has a first opening and a second opening arranged opposite to each other; the positive electrode cover plate is installed in the first opening, and the negative electrode cover plate is installed in the second opening; The second component is subjected to shaping processing by a shaping mold, so that the first metal shell and the second metal shell are bonded to each other, the positive electrode cover plate and the first metal shell and the second metal shell are bonded to each other, and the negative electrode cover plate and the first metal shell and the second metal shell are bonded to each other; Performing sealing welding on the second component after shaping to seal the accommodating space; The sealed second assembly is post-processed to obtain a battery cell.

10. The battery processing method according to claim 9, wherein: The welding of the positive electrode ear and the positive electrode cover plate, and the welding of the negative electrode ear and the negative electrode cover plate, comprises: Welding the positive electrode ear and the inner lead-out sheet of the positive electrode cover plate according to preset welding parameters to form a positive electrode weld; Welding the negative electrode ear and the inner lead-out sheet of the negative electrode cover plate according to preset welding parameters to form a negative electrode weld; The positive electrode weld and the negative electrode weld are subjected to a glue treatment.

11. The battery processing method according to claim 9, wherein: The step of placing the first component covered with the insulating film into a containing space formed by the first metal shell and the second metal shell comprises: After the first metal shell is covered on the front of the first component, the first component covered with the first metal shell is turned over, The second metal shell is covered on the reverse side of the first component, so that the first metal shell and the second metal shell are covered to form the accommodating space.

12. The battery processing method according to claim 9, wherein: The step of shaping the second component by using a shaping mold comprises: loading the second component into the shaping mold; The first metal shell and the second metal shell are pressed and shaped by the shaping mold so that the welding skirt of the first metal shell and the welding skirt of the second metal shell, the positive electrode cover plate and the edge shell of the first opening, and the negative electrode cover plate and the edge shell of the second opening are fitted to each other.

13. The battery processing method according to claim 9, wherein: The step of sealing and welding the second component after shaping to seal the accommodating space comprises: Performing sealing welding on the front side of the second component according to the first preset sealing welding parameters to form a first sealing welding seam surrounding the accommodating space, so as to seal the assembly gaps between the welding skirt of the first metal shell and the welding skirt of the second metal shell, between the front side of the positive electrode cover plate and the first metal shell corresponding to the first opening, and between the front side of the negative electrode cover plate and the first metal shell corresponding to the second opening; The reverse side of the pole core cover plate shell assembly is sealed and welded according to the second preset sealing parameters, and a second sealing weld is formed at a position corresponding to the positive cover plate and the negative cover plate, so as to seal the assembly gap between the reverse side of the positive cover plate and the second metal shell corresponding to the first opening, and between the reverse side of the negative cover plate and the second metal shell corresponding to the second opening.

14. The battery processing method according to claim 9, wherein: The preparation of the first metal shell and the second metal shell comprises: The metal sheet is stamped according to preset stamping parameters to obtain the first metal shell having a first cavity, and the second metal shell having a second cavity adapted to the first cavity; wherein, when the first metal shell and the second metal shell are covered, the first cavity and the second cavity are connected and enclose the accommodating space.

15. The battery processing method according to claim 9, wherein: A liquid injection hole is provided on the positive electrode cover plate or the negative electrode cover plate; The step of injecting liquid into the sealed second component comprises: injecting electrolyte into the accommodation space of the baked second component through the injection hole, and temporarily sealing the injection hole; The step of chemically forming the sealed second component comprises: After the second component that has undergone temporary sealing treatment is subjected to chemical treatment, the injection hole is subjected to permanent sealing treatment.

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