Battery top cover for secondary battery

Abstract

The battery top cover for the secondary battery comprises a positive / negative terminal, a top cover substrate and a lower plastic part, the positive / negative terminal comprises a plane part and a protruding part formed by stamping, and the back surface of the protruding part is provided with a concave part; the protruding part of the terminal penetrates through the top cover substrate and the lower plastic part, the lower end of the terminal can be connected with the switching piece when the battery is assembled, and the plane part of the terminal is matched with the switching piece to clamp the top cover substrate and the lower plastic part; a positive / negative insulating ring, a fixing ring and a sealing ring are sleeved on the protruding part of the terminal; a plurality of upper bulges matched with the terminals and lower bulges matched with the top cover substrate are respectively arranged on the upper surface and the lower surface of the positive / negative electrode insulating ring; the array radiuses of the upper bulges and the lower bulges are different; a plurality of lower grooves matched with the upper bulges are formed in the plane part of the terminal; a plurality of upper grooves matched with the lower bulges are formed in the top cover substrate; an annular bulge is arranged on the upper surface of the fixing ring; sawtooth structures are arranged on the inner circumferential wall and the outer circumferential wall of the annular protrusion. According to the utility model, the simplification and integration of the structure are realized, and the performance and the manufacturing efficiency of the battery cell top cover are improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of secondary batteries, and in particular relates to a secondary battery top cover. Background Art

[0002] Secondary batteries, especially lithium-ion batteries, have gradually become the star in today's energy storage field with their unique advantages. Its emergence not only solves the problems of low energy density of traditional secondary batteries and the inability to reuse primary batteries, but more importantly, lithium-ion batteries are environmentally friendly, have no memory effect, and have low self-discharge rates, making them widely used in electric vehicles, smart phones, laptops, wearable devices, energy storage power stations and other fields.

[0003] Batteries, as the core components of various energy storage devices, carry the important functions of storing and releasing energy. The performance of batteries directly determines the overall performance of energy storage devices, including energy density, cycle life, safety performance, etc. The battery cover, as an important component of the battery, plays a role that cannot be ignored. It not only ensures the sealing of the battery interior to prevent electrolyte leakage, but also ensures that the current can be transmitted smoothly, and at the same time plays a role in safety protection during battery operation.

[0004] The basic principle of battery top cover design is to ensure the safety and stability of the battery under normal use and extreme conditions. Factors that need to be considered in top cover design include but are not limited to: sealing, preventing electrolyte leakage and ensuring the sealing of the battery; safety, generally with a safety valve, which automatically opens when the internal pressure exceeds the safety threshold to release pressure and prevent battery explosion; electrical connection, providing stable and reliable electrical connection, reducing resistance and improving efficiency.

[0005] In the existing technology, electrical connections can be divided into two categories: injection molding and riveting. The injection molded top cover has the following advantages: 1. Good electrical performance, the positive and negative terminals are processed with a whole piece of metal material, and the welding area is large; 2. Precision manufacturing, the injection molded top cover can achieve complex shapes and structures through precise mold design, ensuring good dimensional accuracy and consistency; 3. Material diversity, a variety of high-performance engineering plastics can be used for injection molding, these materials have excellent chemical stability, temperature resistance and sealing; 4. Cost-effectiveness: For large-scale production, the production process of the injection molded top cover is short, the production efficiency is high, and the manufacturing cost of a single piece is relatively low. The injection molded top cover has the following disadvantages: 1. High mold cost: The cost of high-precision molds is high, which is not economical for small batch production; 2. Size limitation, because the injection molded part needs to occupy more space, the size of the top cover designed with injection molding cannot be made small, otherwise it cannot be manufactured. The main advantages of riveted top covers are as follows: 1. Structural stability. The upper and lower pole blocks are fixed by physical connection, which can provide good mechanical strength and durability. 2. Wide range of applicable sizes: The top covers of riveted technology are basically not subject to size restrictions, and different sizes can be designed according to needs. 3. Simplified production process: The production process of riveted top covers is relatively simple, does not require complex molds, and is suitable for small batches and diversified production needs. The main disadvantages of riveted top covers are as follows: 1. Reliability issues: Compared with injection molded top covers, riveted top covers will produce more metal chips and contaminate the product due to the extrusion process during the riveting process, and the terminal poles are prone to breakage. 2. Low production efficiency: The riveting process may be lower in production efficiency than the injection molding process, especially in large-scale production. The efficiency problem is more prominent; 3. Sealing issues: Although the sealing can be improved through design optimization, the sealing performance of riveted top covers is usually not as good as that of injection molded top covers, especially in demanding projects.

[0006] The traditional battery top cover is usually composed of multiple parts, such as the top cover substrate, safety valve, positive and negative terminals, positive and negative pole blocks, lower plastic parts, sealing rings, etc. These parts need to be fixed on the top cover substrate by welding, riveting or injection molding. The inventor found through research that although such a design can meet the basic functions, in the actual production process, the complex assembly steps may lead to low production efficiency and increase manufacturing costs, and also increase potential quality risks, such as poor welding, poor sealing, poor riveting, and pole fracture. In addition, the multi-component structure may also become loose due to long-term use or environmental influences, affecting the stability and safety of the battery. Secondly, the selection of top cover materials and process treatment are not scientific enough, which will cause safety problems in the use of the battery, such as thermal runaway, short circuit, etc. In addition, with the development of high-energy-density lithium-ion batteries, the performance requirements for battery top covers are getting higher and higher, and traditional design and manufacturing technologies are no longer competent.

[0007] In this context, the market urgently needs a new type of battery cell cover that can reduce manufacturing costs, improve production efficiency, and enhance battery cell safety while ensuring battery cell performance. Summary of the invention

[0008] The purpose of the utility model is to overcome the above-mentioned deficiencies of the prior art and provide a battery top cover for a secondary battery, thereby achieving structural simplification and integration, and improving the performance and manufacturing efficiency of the battery top cover.

[0009] The inventor has found through research that stamping technology can be used to stamp metal sheets through molds to produce parts with precise shapes and sizes. Applying stamping technology to the manufacture of battery cell top covers can achieve rapid and mass production of top covers while ensuring the structural accuracy and consistency of the top covers. At the same time, stamping technology can also be combined with laser welding, resistance welding and other processes to achieve reliable connection between the top cover and other parts of the battery cell, thereby improving the overall performance of the battery cell. The battery top cover for a secondary battery proposed in the utility model uses a one-time stamping process to manufacture positive and negative terminals, which can simplify the manufacturing process, reduce costs, and improve production efficiency while ensuring battery performance and safety, while enhancing the structural strength and sealing of the top cover.

[0010] To achieve the above purpose, the technical solution adopted by the utility model is as follows: a battery top cover for a secondary battery, including positive / negative terminals (positive terminal, negative terminal), a top cover substrate, and a lower plastic part.

[0011] The positive / negative terminals include a flat portion and a protrusion formed by stamping, and a recess is formed on the back of the protrusion for connecting to the bus when the batteries are grouped; the protrusions of the positive / negative terminals are passed through the top cover substrate and the lower plastic part, and the lower ends can be connected to the adapter plates (positive adapter plates, negative adapter plates) when the batteries are assembled, and the flat portions of the positive / negative terminals cooperate with the adapter plates to clamp the top cover substrate and the lower plastic part; the protrusions of the positive / negative terminals are covered with positive / negative insulating rings (positive insulating rings, negative insulating rings), fixing rings, and sealing rings.

[0012] The positive / negative insulating ring is located between the positive / negative terminal and the top cover substrate; protrusions are provided on the upper and lower surfaces of the positive / negative insulating ring; the protrusions include a plurality of upper protrusions distributed in a circular array on the upper surface of the positive / negative insulating ring for cooperating with the positive / negative terminal, and a plurality of lower protrusions distributed in a circular array on the lower surface of the positive / negative insulating ring for cooperating with the top cover substrate; the array radius of the upper protrusions is different from the array radius of the lower protrusions to ensure that the assembly cannot be performed in reverse.

[0013] The plane part of the positive / negative terminal is provided with a plurality of lower grooves matched with the upper protrusions; and the top cover substrate is provided with a plurality of upper grooves matched with the lower protrusions.

[0014] The outer contour of the protrusion on the positive electrode insulating ring is different from that of the protrusion on the negative electrode insulating ring to ensure that the positive and negative electrode insulating rings cannot be assembled when they are interchanged.

[0015] The fixing ring and the sealing ring are located between the lower plastic part and the adapter plate.

[0016] An annular protrusion is provided on the upper surface of the fixing ring; a serration structure is provided on the inner and outer circumferential walls of the annular protrusion, which is used to clamp the fixing ring between the top cover substrate and the positive / negative terminals, so as to facilitate the fixing of the positive / negative terminals and the positive / negative insulating rings to the top cover substrate, and prevent the positive / negative terminals from falling off during flipping, transportation and use.

[0017] The lower end of the positive / negative terminal protrusion is provided with a step for connecting with the adapter sheet.

[0018] The height of the step is matched to the thickness of the adapter plate, and the diameter of the step is slightly smaller than the diameter of the terminal assembly hole on the adapter plate.

[0019] The lower surface of the fixing ring is provided with a plurality of protruding columns distributed in an annular array for cooperating with the sealing ring.

[0020] The diameter of the protruding column is slightly larger than the circular hole of the sealing ring, and the sealing ring can be fixed after being matched with each other.

[0021] The sealing ring is provided with a plurality of circular holes adapted to the protruding columns.

[0022] The upper surface of the positive / negative electrode insulating ring is provided with a step.

[0023] The lower plastic part is provided with a positioning ridge for positioning the adapter plate.

[0024] The top cover substrate is provided with a connecting groove for easy connection with the lower plastic part; the lower plastic part is provided with a connecting boss that matches the connecting groove on the top cover substrate; the outer diameter of the connecting boss is larger than the inner diameter of the connecting groove.

[0025] It also includes a bus bar; both ends of the bus bar are provided with protrusions for assembling with the positive / negative terminal recesses, and the middle part of the bus bar is provided with a bending part for easy telescopic bending.

[0026] The battery top cover of the utility model has a groove on the front side, and the busbar with a protruding structure can be easily grouped. The protruding part of the busbar cooperates with the concave part of the battery top cover terminal to achieve fixation, without the need for additional positioning methods, and has the characteristics of reliable connection and simple process.

[0027] Compared with the prior art, the beneficial effects of the utility model are:

[0028] 1) The utility model proposes a new battery top cover structure, which uses positive and negative terminals manufactured by stamping to complete the functions of current conduction, fixation, and sealing. Compared with the poles manufactured by friction welding, the integrated terminal has good sealing and high reliability. The height of the top cover is reduced by more than 20%. When the external dimensions of the battery cell are fixed, the height of the winding core can be increased, thereby improving the energy density of the battery cell;

[0029] 2) The utility model uses less positive and negative terminal materials, saving material costs; the stamping manufacturing method is adopted, which has high efficiency and good precision;

[0030] 3) In the manufacturing process of the battery top cover, except for the welding of the explosion-proof valve, there is no need to weld parts, which improves production efficiency and reduces equipment investment and production costs;

[0031] 4) The positive and negative terminals, insulating rings and top cover substrates are designed with protrusions and grooves of different shapes and sizes to prevent mistakes in the positive and negative polarities during assembly, and to prevent mistakes in the assembly process of different materials, which is simple and reliable;

[0032] 5) The terminal structure is pre-fixed using a fixing ring, which is convenient for manufacturing, transportation and use. At the same time, the fixing ring also has a secondary sealing effect, which improves the sealing of the top cover terminal;

[0033] 6) During welding, the adapter is directly connected to the terminal structure, which shortens the current conduction distance. The battery with this top cover can achieve lower heat generation and higher rate;

[0034] 7) When grouped, the top cover has a mechanical anti-mistake structure. The groove of the top cover terminal can cooperate with the protrusion of the bus. When the positioning deviation between the bus and the terminal is large, it can still slide into place by shape. The bus welding does not require precise positioning measures (machine vision, mechanical positioning, auxiliary tooling, etc.), with high reliability and simple process. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic structural diagram of a battery top cover for a secondary battery.

[0036] Figure 2 An exploded view of a battery top cover for a secondary battery.

[0037] Figure 3 A top view of a battery cover for a secondary battery.

[0038] Figure 4 for Figure 3 AA section view.

[0039] Figure 5 for Figure 4 Enlarged view of part I in the middle.

[0040] Figure 6 for Figure 4 Enlarged view of part II.

[0041] Figure 7 The figure is a bottom view of a battery top cover for a secondary battery.

[0042] Figure 8 A top view of the top cover substrate.

[0043] Fig. 9 for Figure 8 AA section view.

[0044] Fig.10 A bottom view of the top cover substrate.

[0045] Fig.11 It is a schematic diagram of the structure of the positive terminal.

[0046] Fig.12 This is the front view of the positive terminal.

[0047] Fig.13 for Fig.12 Bottom view of .

[0048] Fig.14 for Fig.12 Top view of the .

[0049] Fig.15 for Fig.14 AA section view.

[0050] Fig.16 It is a schematic diagram of the structure of the positive electrode insulating ring.

[0051] Fig.17 This is the front view of the positive electrode insulating ring.

[0052] Fig.18 for Fig.17 Bottom view of .

[0053] Fig.19 for Fig.17 Top view of the .

[0054] Fig. 20 Schematic diagram of the structure of the negative terminal.

[0055] Fig.21 This is the front view of the negative terminal.

[0056] Fig. 22 for Fig.21 Top view of the .

[0057] Fig.23 for Fig. 22 AA section view.

[0058] Fig.24 for Fig.21 Bottom view of .

[0059] Fig.25 Schematic diagram of the structure of the negative electrode insulation ring.

[0060] Fig.26 This is the front view of the negative electrode insulating ring.

[0061] Fig. 27 for Fig.26 Bottom view of .

[0062] Fig.28 for Fig.26 Top view of the .

[0063] Fig.29 It is a schematic diagram of the structure of the lower plastic part.

[0064] Fig.30 This is the front view of the lower plastic part.

[0065] Fig.31 for Fig.30 Bottom view of .

[0066] Fig.32 for Fig.30 Top view of the .

[0067] Fig.33 It is a schematic diagram of the structure of the fixed ring.

[0068] Fig.34 The front view of the fixing ring.

[0069] Fig.35 for Fig.34 Bottom view of .

[0070] Fig.36 for Fig.34 Top view of the .

[0071] Fig.37 for Fig.36 AA section view.

[0072] Fig.38 It is a schematic diagram of the structure of the positive electrode adapter.

[0073] Fig.39 It is a schematic diagram of the structure of the negative electrode adapter.

[0074] Fig.40 This is a schematic diagram of the bus structure.

[0075] Fig.41 This is the second schematic diagram of the bus structure.

[0076] Fig.42 This is one of the schematic diagrams of the secondary battery assembly steps.

[0077] Fig.43 This is the second schematic diagram of the secondary battery assembly steps.

[0078] Fig.44 Schematic diagram of the structure of a secondary battery.

[0079] Fig.45 It is a schematic diagram of the structure of a secondary battery pack.

[0080] In the figure: battery top cover 0, bare cell 01, secondary battery 111, secondary battery pack 131, positive terminal 1, plane part 101, protrusion 102, lower groove 103, step 104, recess 105, negative terminal 2, plane part 201, protrusion 202, lower groove 203, step 204, recess 205, positive electrode insulating ring 3, step 301, upper protrusion 302, lower protrusion 303, negative electrode insulating ring 4, step 401, upper protrusion 402, lower protrusion 403, explosion-proof valve sheet 5, explosion-proof valve protection sheet 6, top cover substrate 7 , upper groove 701, upper groove 702, explosion-proof valve hole 703, injection hole 704, connecting groove 705, lower plastic part 8, positive terminal hole 801, negative terminal hole 802, positioning ridge 803, lower plastic boss 804, electrolyte leakage hole 805, connecting boss 806, fixing ring 9, annular protrusion 901, protruding column 902, sealing ring 10, circular hole 1001, positive electrode adapter 11, assembly hole 1101, negative electrode adapter 12, assembly hole 1201, bus 13, protrusion 1301, bending portion 1302. DETAILED DESCRIPTION

[0081] The battery top cover for the secondary battery of the utility model comprises a positive terminal 1, a negative terminal 2, a positive insulating ring 3, a negative insulating ring 4, an explosion-proof valve sheet 5, an explosion-proof valve protection sheet 6, a top cover substrate 7, a lower plastic part 8, a fixing ring 9, and a sealing ring 10. Figure 1-7 As shown. The battery cover for secondary batteries of the utility model covers the design of positive and negative terminals, as well as the application of positive and negative insulating rings, fixing rings and sealing rings. The focus is on the simplification of components, simplified assembly process, installation convenience and foolproof design of the battery cover. The fixing ring temporarily fixes the positive and negative terminals, and forms a complete structure after welding with the adapter. At the same time, the step design of the positive and negative terminals, the raised design of the positive and negative insulating rings, and the coordinated use of the fixing ring and the sealing ring are introduced, emphasizing the ease of assembly and the design of preventing mis-installation.

[0082] The top cover substrate 7 is made of aluminum material, and the positions of the positive and negative terminals are provided with upper grooves 701 and 702 that cooperate with the insulating rings. Figure 8-10 As shown, 703 is the explosion-proof valve hole, 704 is the injection hole, and 705 is the connecting groove.

[0083] The positive terminal 1 is made of aluminum material, preferably Al3003, with a thickness of 0.6mm-3mm, and is manufactured by stamping. The protrusion 102 includes a step 104, and the plane portion 101 has a groove 103, which can cooperate with the positive electrode insulating ring, such as Figure 11-15 As shown. The positive terminal 1 includes a flat portion 101 and a protrusion 102 formed by stamping. A recess 105 is formed on the back of the protrusion 102 for connecting to the bus 13 when the batteries are grouped. The positive terminal protrusion 102 is passed through the positive insulating ring 3, the top cover substrate 7, the lower plastic part 8, the fixing ring 9, and the sealing ring 10. The lower end can be connected to the positive adapter 11 when the battery is assembled. A step 104 for connecting to the positive adapter is provided at the lower end of the positive terminal protrusion 102. The height of the step 104 is adapted to the thickness of the positive adapter. The diameter of the step 104 is slightly smaller than the terminal assembly hole 1101 on the positive adapter ( Fig.38 shown).

[0084] The negative terminal 2 is made of copper-aluminum composite plate material, 206 is an aluminum layer, 207 is a copper layer, the aluminum material part is preferably Al3003, the copper part is preferably Cu-T2, the thickness is controlled at 0.6mm-3mm, and it is manufactured by stamping. The protrusion 202 includes a step 202, and the plane part 201 has a groove 203, which can cooperate with the negative electrode insulation ring, such as Figure 20-24 As shown. The negative terminal 2 includes a flat portion 201 and a protrusion 202 formed by stamping. A recess 205 is formed on the back of the protrusion 202 for easy connection with the bus 13 when the batteries are grouped. The negative terminal protrusion 202 is passed through the negative insulating ring 4, the top cover substrate 7, the lower plastic part 8, the fixing ring 9, and the sealing ring 10. The lower end can be connected to the negative electrode adapter 12 when the battery is assembled. The fixing ring 9 is used to temporarily fix the lower plastic part 8 to prevent the top cover from falling off during transportation. The positive terminal flat portion 101 cooperates with the positive electrode adapter 11, and the negative terminal flat portion 201 cooperates with the negative electrode adapter 12 to clamp the top cover substrate 7 and the sealing ring 10. A step 204 for connecting to the negative electrode adapter is provided at the lower end of the negative terminal protrusion 202. The height of the step 204 is adapted to the thickness of the negative electrode adapter, and the diameter of the step 204 is slightly smaller than the terminal assembly hole 1201 on the negative electrode adapter ( Fig.39 shown).

[0085] like Figure 16-19As shown, the positive insulating ring 3 is made of plastic or ceramic, glass, or resin, and is in a weakly conductive or insulating state. It includes a step 301, and has protrusions on the upper and lower surfaces. The array radius of the lower protrusion 303 is different from that of the upper protrusion 302, ensuring that the assembly cannot be performed in the reverse direction. Since there is no step at the contact part with the terminal after reverse assembly, it is easy to cause glue overflow during welding. The positive insulating ring is located between the positive terminal and the top cover substrate 7. Protrusions are provided on the upper and lower surfaces of the positive insulating ring; the protrusions include a plurality of upper protrusions 302 distributed in an annular array on the upper surface of the positive / negative insulating ring for cooperating with the positive / negative terminal, and a plurality of lower protrusions 303 distributed in an annular array on the lower surface of the positive / negative insulating ring for cooperating with the top cover substrate 7; the array radius of the upper protrusion is different from that of the lower protrusion, which plays a fool-proof role and ensures that the assembly cannot be performed in the reverse direction. The flat surface 101 of the positive terminal is provided with a plurality of lower grooves 103 adapted to the upper protrusions; the top cover substrate 7 is provided with a plurality of upper grooves 701 adapted to the lower protrusions.

[0086] like Figure 25-28 As shown, the negative electrode insulating ring 4 is made of plastic or ceramic, glass, or resin, and is in a weakly conductive or insulating state. It includes a step 401, and has protrusions on the upper and lower surfaces. The array radius of the lower protrusion 403 is different from that of the upper protrusion 402, ensuring that the reverse assembly is impossible. Compared with the positive electrode insulating ring, the protrusion shape of the negative electrode insulating ring is different, ensuring that the positive and negative electrode insulating rings cannot be assembled when they are interchanged. The negative electrode insulating ring is located between the negative terminal and the top cover substrate 7. Protrusions are provided on the upper and lower surfaces of the negative electrode insulating ring; the protrusions include a plurality of upper protrusions 402 distributed in an annular array on the upper surface of the positive / negative electrode insulating ring for matching with the positive / negative terminal, and a plurality of lower protrusions 403 distributed in an annular array on the lower surface of the positive / negative electrode insulating ring for matching with the top cover substrate 7; the array radius of the upper protrusion is different from that of the lower protrusion, which plays a fool-proof role and ensures that the reverse assembly is impossible. The plane portion 201 of the negative terminal is provided with a plurality of lower grooves 203 adapted to the upper protrusions; the top cover substrate 7 is provided with a plurality of upper grooves 702 adapted to the lower protrusions.

[0087] The outer contour of the protrusion on the positive insulating ring is different from that of the protrusion on the negative insulating ring, which plays an anti-mistake role to ensure that the positive and negative insulating rings cannot be assembled when they are interchanged.

[0088] The high temperature during welding of the positive and negative terminals to the busbar will cause a slight melting of the plastic insulating ring. After the steps 301 and 401 are arranged on the upper surface of the positive / negative insulating ring, the melting can be reduced and the melted material can be prevented from overflowing and affecting the terminal appearance. When other heat-resistant materials such as ceramics and glass are used, the steps can ensure that the edge of the terminal will not be directly squeezed to the edge of the insulating ring, resulting in noticeable damage.

[0089] like Figure 29-32As described, the lower plastic part 8 is made of plastic material, and has a positive terminal hole 801 for accommodating a positive terminal, a negative terminal hole 802 for accommodating a negative terminal, a positioning ridge 803 that can be positioned in place to ensure that the positive adapter 11 and the negative adapter 12 will not be skewed during assembly, a lower plastic boss 804 that can accommodate the folded pole ear is provided to ensure that there is a certain space between the top cover and the bare cell after the top cover and the bare cell are assembled, an electrolyte leakage hole 805 that ensures that the electrolyte can leak, and a connecting boss 806 that cooperates with the connecting groove 705 on the top cover substrate 7. The diameter of the connecting boss 806 is slightly larger than the connecting groove 705. Since the plastic material used in the lower plastic part 8 has a certain compressibility, it can be ensured that the connecting boss 806 can be inserted into the connecting groove 705, and a certain connection strength can be ensured, and it will not fall off during subsequent use.

[0090] like Figure 33-37 As shown, the fixing ring 9 is made of plastic material, and has an annular protrusion 901 with a serrated structure on the upper part. The inner and outer circumferential walls of the annular protrusion 901 are provided with serrated structures, which can be stuck in the gap between the top cover substrate and the positive and negative terminals. The lower part has a protruding column 902, which can cooperate with the sealing ring 10 to fix the sealing ring 10. The sealing ring 10 is made of fluororubber material and is distributed with a circle of circular holes 1001, which can cooperate with the protruding column 902 of the fixing ring. The fixing ring 9 and the sealing ring 10 are located between the lower plastic part 8 and the positive / negative electrode adapter.

[0091] like Figure 40-41 As shown, protrusions 1301 for assembling with the positive / negative terminal recesses 105 are provided at both ends of the busbar 13, and a bending portion 1302 that can be extended and bent conveniently is provided in the middle of the busbar 13.

[0092] like Figure 42-44 As shown, the secondary battery 111 using the battery top cover is assembled using the following assembly method:

[0093] 1) Prepare two bare cells 01, shape the tabs of the bare cells so that they are biased toward the bottom, perform ultrasonic pre-welding on the tabs to temporarily fix the tabs of the bare cells, and then cut the front ends of the tabs neatly;

[0094] 2) Prepare the positive electrode adapter 11 and the negative electrode adapter 12, fix the bare battery cell and the adapter on the tooling, place the bare battery cell tabs on the legs of the positive and negative electrode adapters, perform ultrasonic welding, and stick termination tapes on the front and back after welding;

[0095] 3) Prepare the battery top cover 0 and the bare battery cell with the adapter welded, fix them on the tooling, match the round hole of the adapter with the step on the positive / negative terminal of the battery top cover, press the welding tooling into place, and make the adapter fit tightly with the lower plastic part;

[0096] 4) Laser weld the gap between the adapter and the positive / negative terminals, fold the bare battery cell, fix it with termination tape, wrap it with mylar film (polyester film), and put it into the battery shell;

[0097] 5) The assembled battery cells are made into secondary batteries after sealing welding, baking, liquid injection, formation, aging and capacity division processes.

[0098] like Fig.45 As shown, the secondary battery pack 131 using the battery top cover is connected by the following grouping method:

[0099] 1) Alternately arrange the secondary batteries 111 according to the positive and negative polarities and fix them externally with steel tape, adhesive tape, etc.;

[0100] 2) Prepare the busbar 13, and press the protrusions at both ends of the busbar into the recesses of the positive / negative terminals of the battery top cover;

[0101] 3) The flat surface of the bus is laser welded to form a secondary battery pack.

Claims

1. A battery top cover for a secondary battery, characterized in that: Includes positive / negative terminals, top cover substrate, and lower plastic parts; The positive / negative terminals include a flat surface and a protrusion formed by stamping, and a concave portion is formed on the back of the protrusion to facilitate connection when the batteries are grouped; the protrusion of the positive / negative terminal is penetrated through the top cover substrate and the lower plastic part, and the lower end can be connected to the adapter when the battery is assembled, and the flat surface of the positive / negative terminal cooperates with the adapter to clamp the top cover substrate and the lower plastic part; the protrusion of the positive / negative terminal is sleeved with a positive / negative insulation ring, a fixing ring, and a sealing ring; The positive / negative insulating ring is located between the positive / negative terminal and the top cover substrate; the upper and lower surfaces of the positive / negative insulating ring are provided with protrusions; the protrusions include a plurality of upper protrusions distributed in an annular array on the upper surface of the positive / negative insulating ring for cooperating with the positive / negative terminal, and a plurality of lower protrusions distributed in an annular array on the lower surface of the positive / negative insulating ring for cooperating with the top cover substrate; the array radius of the upper protrusions is different from the array radius of the lower protrusions; The plane part of the positive / negative terminal is provided with a plurality of lower grooves adapted to the upper protrusions; the top cover substrate is provided with a plurality of upper grooves adapted to the lower protrusions; The outer contour of the protrusion provided on the positive electrode insulating ring is different from the outer contour of the protrusion provided on the negative electrode insulating ring; The fixing ring and the sealing ring are located between the lower plastic part and the adapter plate; An annular protrusion is provided on the upper surface of the fixing ring; a serration structure is provided on the inner and outer circumferential walls of the annular protrusion, which is used to clamp the fixing ring between the top cover substrate and the positive / negative terminals, so as to facilitate the fixing of the positive / negative terminals and the positive / negative insulating rings to the top cover substrate.

2. The battery top cover for a secondary battery according to claim 1, characterized in that: The lower end of the positive / negative terminal protrusion is provided with a step for connecting with the adapter sheet.

3. The battery top cover for a secondary battery according to claim 2, characterized in that: The height of the step is matched to the thickness of the adapter plate, and the diameter of the step is smaller than the diameter of the terminal assembly hole on the adapter plate.

4. The battery top cover for a secondary battery according to claim 1, characterized in that: The lower surface of the fixing ring is provided with a plurality of protruding columns distributed in an annular array for cooperating with the sealing ring.

5. The battery top cover for a secondary battery according to claim 4, characterized in that: The diameter of the protruding column is larger than the circular hole of the sealing ring, and the sealing ring can be fixed after being matched with each other.

6. The battery top cover for a secondary battery according to claim 4, characterized in that: The sealing ring is provided with a plurality of circular holes adapted to the protruding columns.

7. The battery top cover for a secondary battery according to claim 1, characterized in that: The upper surface of the positive / negative electrode insulating ring is provided with a step.

8. The battery top cover for a secondary battery according to claim 1, characterized in that: The lower plastic part is provided with a positioning ridge for positioning the adapter plate.

9. The battery top cover for a secondary battery according to claim 1, characterized in that: The top cover substrate is provided with a connecting groove for easy connection with the lower plastic part; the lower plastic part is provided with a connecting boss that matches the connecting groove on the top cover substrate; the outer diameter of the connecting boss is larger than the inner diameter of the connecting groove.

10. The battery top cover for a secondary battery according to claim 1, characterized in that: It also includes a bus bar; both ends of the bus bar are provided with protrusions for assembling with the positive / negative terminal recesses, and the middle part of the bus bar is provided with a bending part for easy telescopic bending.

Images