Lithium secondary battery and method for manufacturing the same

Abstract

Provided are a lithium secondary battery and a method for manufacturing the same. 【Solution means】The lithium battery includes a voltage adjustment circuit assembly 1, a plastic frame 2, a first metal case 3, a lithium ion cell 4, and an insulating outer skin 5. The lithium ion cell includes a wound cell assembly, a high-voltage positive electrode cap assembly, and a second metal case. An annular rolling slot that divides the second metal case into a main body part and a contraction part is provided at the upper part of the second metal case. The contraction part of the second metal case is embedded in the first metal case, and the outer surfaces of the first metal case and the second metal case are flush. 【Effect】In this application, a complete and independent lithium ion cell is fabricated, and then formation and capacity grading are performed, and a qualified lithium battery is selected and placed in the first metal case, so that the defective rate of the product can be significantly reduced. The first and second metal cases are easy to disassemble and convenient for maintenance.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium batteries, and particularly to lithium secondary batteries and their manufacturing methods.

Background Art

[0002] A low-voltage lithium battery converts the high voltage of a lithium battery to a low voltage of 1.5V through a voltage drop circuit board, and is manufactured according to the sizes of AA batteries, AAA batteries, etc., and can replace ordinary alkaline batteries and nickel-metal hydride batteries.

[0003] Chinese Patent Application Publication No. CN118315645A discloses a buck-type lithium battery, but since it adopts the process of performing formation after packaging, it is inevitable that defective products that do not meet the capacity requirements will occur in the subsequent capacity grading process, and it is impossible to disassemble the lithium battery without destroying it after packaging, and it is difficult to reuse the voltage adjustment circuit assembly with high internal value, so there is room for improvement.

Summary of the Invention

Problems to be Solved by the Invention

[0004] Since existing low-voltage lithium batteries adopt the process of performing formation after packaging, in order to solve the technical problem that defective products occur in the subsequent capacity grading process, the present invention provides a lithium secondary battery and its manufacturing method.

Means for Solving the Problems

[0005] In one aspect, the present invention provides the following technical solutions. A lithium secondary battery, A voltage regulation circuit assembly, a plastic frame, a first metal case, a lithium ion cell, and an insulating outer skin, wherein the voltage regulation circuit assembly and the plastic frame are provided within the first metal case, the plastic frame is used to fix the voltage regulation circuit assembly, the lithium ion cell includes a wound cell assembly, a high voltage positive electrode cap assembly, and a second metal case, an annular rolling slot is provided at the upper part of the second metal case, the wound cell assembly is provided within the second metal case and is positionally restricted by the annular rolling slot, the second metal case is divided by the annular rolling slot into a lower main body part and an upper contraction part, the outer diameter of the first metal case is the same as the outer diameter of the main body part of the second metal case, the inner diameter of the first metal case is the same as the outer diameter of the contraction part of the second metal case, the contraction part of the second metal case is embedded within the first metal case, the outer surfaces of the first metal case and the second metal case are flush, and the insulating outer skin covers the outside of the first metal case and the second metal case.

[0006] By adopting the above technical solution, the voltage regulation circuit assembly of the lithium secondary battery of the present application is provided with necessary circuits such as a step-down circuit, a voltage stabilization circuit, a charging circuit, an over-discharge protection circuit, etc., is electrically connected to the lithium ion cell, and by using the low voltage positive electrode cap as the battery positive electrode and the second metal case as the battery negative electrode, a low voltage can be stably output.

[0007] This application can solve the technical problem that lithium batteries in the prior art do not meet the capacity requirements, greatly reduce the defective rate of products, and manufacture a complete and independent lithium-ion cell, then perform formation and capacity grading, select a qualified lithium battery and place it in the first metal case. When the contraction part of the second metal case is embedded in the first metal case and the dimensions are appropriate, a large static friction force is generated by the tight fitting of the outer wall of the contraction part of the second metal case and the inner wall of the first metal case, which can preferably prevent the first metal case and the second metal case from separating. Furthermore, by covering the insulating outer skin on the outside of the first metal case and the second metal case, it further guarantees that the first metal case and the second metal case cannot be separated, ensuring the integrity of the lithium battery. If a defect is found during detection, after removing the insulating outer skin, the first metal case and the second metal case can be separated by pulling them apart, and the disassembly is very easy. If there is a problem with the lithium-ion cell, the lithium-ion cell can be replaced; if there is a problem with the voltage regulation circuit assembly, the voltage regulation circuit assembly can be replaced, and the defective voltage regulation circuit assembly can also be reused after maintenance. Of course, the qualified detection of electrical performance can be carried out before covering the insulating outer skin, and the insulating outer skin can be covered for the lithium battery that has passed the detection, so as to avoid unnecessary consumption of the insulating outer skin in this way.

[0008] Optionally, the first metal case and the second metal case are fixedly connected by spot welding, or the lower edge of the first metal case contracts inward to form a contraction opening to define the contraction part of the second metal case.

[0009] Optionally, the voltage regulation circuit assembly includes a low-voltage positive electrode cap, a PCB board, a charging port, a high-voltage positive electrode dome, a negative electrode dome, and an elastic ejector pin. The charging port, high-voltage positive electrode dome, negative electrode dome, and elastic ejector pin are all provided on the PCB board. The plastic frame and the low-voltage positive electrode cap are defined by the top wall of the first metal case. A positive and negative electrode gasket is further provided between the low-voltage positive electrode cap and the top wall of the first metal case. The first metal case is provided with a through hole at the top and a first charging escape hole on the side. The low-voltage positive electrode cap protrudes from the through hole. The charging escape hole is used to expose the charging port of the voltage regulation circuit assembly. The elastic ejector pin abuts against the inner wall of the low-voltage positive electrode cap. The negative electrode dome abuts against the inner wall of the first metal case. The high-voltage positive electrode dome abuts against the high-voltage positive electrode cap assembly. The first metal case and the second metal case are in contact and conduct electricity. A second charging escape hole is provided at the corresponding position on the side of the insulating outer skin.

[0010] Optionally, the plastic frame includes an upper frame and a lower frame that are fastened together, and the PCB board is fixed between the upper frame and the lower frame.

[0011] Optionally, the plastic frame is attached to the inner wall of the first metal case via an adhesive.

[0012] Optionally, the plastic frame is provided in the first metal case so as to be able to move up and down. The high-voltage positive electrode dome is further used to abut the plastic frame against the top wall of the first metal case.

[0013] Optionally, the low-voltage positive electrode cap is attached to the plastic frame via an adhesive. The positive and negative electrode gasket is attached to the plastic frame and the low-voltage positive electrode cap via an adhesive.

[0014] Optionally, on the outer peripheral surface of the plastic frame, there are provided protruding vertical guide strips for reducing the frictional force with the inner wall of the first metal case.

[0015] Optionally, on the negative electrode dome, there are provided protrusions protruding outward, and by contacting the inner wall of the first metal case through the protrusions, the frictional force with the inner wall of the first metal case is reduced.

[0016] In another aspect, another technical solution further provided in the present application is as follows. The method for manufacturing the lithium secondary battery, placing the wound cell assembly in the second metal case, creating an annular rolling slot at the upper part of the second metal case, welding the negative electrode tag of the wound cell assembly to the bottom wall of the second metal case, welding the positive electrode tag to the high-voltage positive electrode cap assembly, injecting the electrolyte, placing the high-voltage positive electrode cap assembly in the second metal case, creating a contraction part at the upper part of the second metal case, and Spinning Edge creating on the upper edge of the second metal case, fixing the high-voltage positive electrode cap assembly in the contraction part to form a lithium-ion cell, and performing step S1 of forming and capacity grading on the lithium-ion cell; step S2 of fixing the voltage regulation circuit assembly to the plastic frame and then incorporating them together into the first metal case; step S3 of embedding the upper end of the lithium-ion cell into the first metal case; including step S4 of covering with an insulating outer skin, performing heat shrinkage, and wrapping the insulating outer skin around the first metal case and the lithium-ion cell.

Advantages of the Invention

[0017] In summary, the present application includes at least one of the following beneficial technical effects. 1. The lithium secondary battery of the present application is provided with a voltage regulation circuit assembly and can stably output a low voltage. 2. This application can solve the technical problem that the lithium batteries in the prior art do not meet the capacity requirements by manufacturing complete and independent lithium-ion cells, and then performing formation and capacity grading, selecting qualified lithium batteries and placing them in the first metal case, and can greatly reduce the defective rate of products. 3. By the outer wall of the contraction part of the second metal case fitting tightly with the inner wall of the first metal case, a large static friction force is generated, which can preferably prevent the first metal case and the second metal case from separating, further ensuring that the insulating outer skin cannot separate the first metal case and the second metal case, guaranteeing the integrity of the lithium battery, and making the disassembly of the first metal case and the second metal case very convenient.

Brief Description of the Drawings

[0018]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Figure 18

Figure 19

Figure 20

Explanation of reference numerals

[0019] 1. Voltage adjustment circuit assembly, 11. Low-voltage positive cap, 12. PCB board, 13. Charging port, 14. High-voltage positive dome, 15. Negative dome, 151. Protrusion, 16. Elastic ejector pin, 17. Positive and negative gaskets, 2. Plastic frame, 21. Upper frame, 22. Lower frame, 23. Vertical guide strip, 24. Annular teeth, 3. First metal case, 31. Through hole, 32. First charging escape hole, 4. Lithium-ion cell, 41. Wound cell assembly, 42. High-voltage positive cap assembly, 43. Second metal case, 431. Annular rolling slot, 432. Body part, 433. Shrinkage part, 434. Spinning Edge 5. Insulating outer skin, 51. Second charging escape hole.

Embodiment for Carrying Out the Invention

[0020] Hereinafter, with reference to FIGS. 1 to 20, the present application will be described in more detail.

[0021] Example 1 With reference to FIGS. 1 to 5, this example discloses a lithium secondary battery including a voltage adjustment circuit assembly 1, a plastic frame 2, a first metal case 3, a lithium-ion cell 4, and an insulating outer skin 5. This example is specifically an AAA battery (single 4-cell battery), but the present application is not limited to AAA batteries.

[0022] With reference to FIGS. 4, 6, and 7, the voltage adjustment circuit assembly 1 and the plastic frame 2 are provided in the first metal case 3, and the plastic frame 2 is used to fix the voltage adjustment circuit assembly 1. The plastic frame 2 includes an attached upper frame 21 and a lower frame 22, and the PCB board 12 is fixed between the upper frame 21 and the lower frame 22. The plastic frame 2 can effectively prevent the PCB board 12 from contacting the first metal case 3 and short-circuiting, and can also fix the PCB board 12 more firmly to prevent the position of the PCB board 12 from changing.

[0023] Referring to FIG. 12, the lithium ion cell 4 includes a wound cell assembly 41, a high-voltage positive electrode cap assembly 42, and a second metal case 43. An annular rolling slot 431 is provided at the upper part of the second metal case 43. The wound cell assembly 41 is provided in the second metal case 43 and is positionally restricted by the annular rolling slot 431. The second metal case 43 is divided by the annular rolling slot 431 into a lower main body portion 432 and an upper shrinkage portion 433.

[0024] Referring to FIGS. 3, 5 and 13, the outer diameter of the first metal case 3 is the same as the outer diameter of the main body portion 432 of the second metal case 43, and the inner diameter of the first metal case 3 is the same as the outer diameter of the shrinkage portion 433 of the second metal case 43. The shrinkage portion 433 of the second metal case 43 is embedded in the first metal case 3, and the outer surfaces of the first metal case 3 and the second metal case 43 are flush. The insulating outer skin 5 covers the outside of the first metal case 3 and the second metal case 43.

[0025] Referring to FIGS. 3, 5 and 6, the voltage adjustment circuit assembly 1 includes a low-voltage positive cap 11, a PCB board 12, a charging port 13, a high-voltage positive dome 14, a negative dome 15, and an elastic ejector pin 16. The charging port 13, the high-voltage positive dome 14, the negative dome 15, and the elastic ejector pin 16 are all provided on the PCB board 12. The plastic frame 2 and the low-voltage positive cap 11 are defined by the top wall of the first metal case 3. A positive and negative electrode gasket 17 is further provided between the low-voltage positive cap 11 and the top wall of the first metal case 3. The first metal case 3 is provided with a through hole 31 at the top and a first charging escape hole 32 on the side. The low-voltage positive cap 11 protrudes from the through hole 31. The charging escape hole is used to expose the charging port 13 of the voltage adjustment circuit assembly 1. The elastic ejector pin 16 abuts against the inner wall of the low-voltage positive cap 11. The negative dome 15 abuts against the inner wall of the first metal case 3. The high-voltage positive dome 14 abuts against the high-voltage positive cap assembly 42. The first metal case 3 and the second metal case 43 are in contact and conduct electricity. A second charging escape hole 51 is provided at a position corresponding to the side surface of the insulating outer skin 5. The positive and negative electrode gasket 17 is used to prevent a short circuit between the low-voltage positive cap 11 and the first metal case 3 and ensure electrical safety.

[0026] In this embodiment, since the plastic frame 2 is attached to the inner wall of the first metal case 3 through an adhesive, it is possible to prevent the plastic frame 2 from rotating within the first metal case 3, avoid displacement, and prevent the charging port 13 from not being completely exposed.

[0027] The manufacturing method of the lithium secondary battery described in this embodiment is Place the wound cell assembly 41 into the second metal case 43, form an annular rolling slot 431 at the upper part of the second metal case 43, weld the negative electrode tag of the wound cell assembly 41 to the bottom wall of the second metal case 43, weld the positive electrode tag to the high-voltage positive electrode cap assembly 42, inject electrolyte, place the high-voltage positive electrode cap assembly 42 into the second metal case 43, create a contraction part 433 at the upper part of the second metal case 43, and at the upper edge of the second metal case 43 Spinning Edge create 434, fix the high-voltage positive electrode cap assembly 42 in the contraction part 433 to form the lithium-ion cell 4, and perform step S1 of forming and capacity grading on the lithium-ion cell 4; After fixing the voltage adjustment circuit assembly 1 to the plastic frame 2, perform step S2 of incorporating them together into the first metal case 3; Perform step S3 of embedding the upper end of the lithium-ion cell 4 into the first metal case 3; Cover with the insulating outer skin 5, perform heat shrinkage, and perform step S4 of wrapping the insulating outer skin 5 around the first metal case 3 and the lithium-ion cell 4.

[0028] The manufacturing method described in the present application has reasonable processes, high yield, and is industrializable, and is particularly suitable for mass production.

[0029] The specific connection principle of the circuit of the present application is as follows: weld the positive electrode tab of the wound cell assembly 41 to the lower surface of the high-voltage positive electrode cap assembly 42 and connect it to the PCB board 12 through the high-voltage positive electrode dome 14. The negative electrode tab of the wound cell assembly 41 is welded to the bottom wall of the second metal case 43 and is connected to the PCB board 12 through the second metal case 43, the first metal case 3, and the negative electrode dome 15. After performing circuit step-down processing on the PCB board 12, output the positive low voltage from the low-voltage positive electrode cap 11 and output the negative electrode of the lithium battery from the second metal case 43.

[0030] The voltage adjustment circuit assembly 1 of the lithium secondary battery of the present application is provided with necessary circuits such as a step-down circuit, a voltage stabilization circuit, a charging circuit, an over-discharge protection circuit, etc., and is electrically connected to the lithium ion cell 4. By using the low-voltage positive electrode cap 11 as the battery positive electrode and the second metal case 43 as the battery negative electrode, a stable low voltage can be output.

[0031] In the present application, a complete and independent lithium ion cell 4 is fabricated, and then formation and capacity grading are performed, and a qualified lithium battery is selected and placed in the first metal case 3. Therefore, the technical problem that the lithium battery in the prior art does not meet the capacity requirement can be solved, the defective rate of the product can be significantly reduced. When the shrinkage part 433 of the second metal case 43 is embedded in the first metal case 3 and the dimensions are appropriate, a large static friction force is generated by the tight fitting of the outer wall of the shrinkage part 433 of the second metal case 43 and the inner wall of the first metal case 3, and the separation of the first metal case 3 and the second metal case 43 can be preferably prevented. Furthermore, by covering the insulating outer skin 5 on the outside of the first metal case 3 and the second metal case 43, it is further guaranteed that the first metal case 3 and the second metal case 43 cannot be separated, ensuring the integrity of the lithium battery. If a defect is found during detection, after removing the insulating outer skin 5, the first metal case 3 and the second metal case 43 can be separated and detached. The disassembly is very easy. If there is a problem with the lithium ion cell 4, the lithium ion cell 4 can be replaced, and if there is a problem with the voltage adjustment circuit assembly 1, the voltage adjustment circuit assembly 1 can be replaced. The defective voltage adjustment circuit assembly 1 can also be reused after maintenance. Of course, the electrical performance qualification detection can be performed before covering the insulating outer skin 5, and the insulating outer skin 5 can be covered for the lithium battery that has passed the detection, so as to avoid the wasteful consumption of the insulating outer skin 5 in this way.

[0032] In this embodiment, when the case structure strength of the lithium battery is further required, the connection relationship between the first metal case 3 and the second metal case 43 can also be strengthened. For example, the first metal case 3 and the second metal case 43 are fixedly connected by spot welding, or the lower edge of the first metal case 3 shrinks inward to form a shrinkage opening, and the shrinkage portion 433 of the second metal case 43 can be defined. Both are feasible and only reduce the ease of detachment, and can be reasonably selected according to the user's usage scenario.

[0033] Embodiment 2 Since the end of the cylindrical battery must contact the negative electrode elastic element in the external battery chamber to achieve electrical connection, the negative electrode elastic element may be deformed or the spring may fall off, which easily causes poor electrical contact of the cylindrical battery.

[0034] Referring to FIGS. 15 and 16, as Embodiment 2 of the lithium secondary battery of the present application, the difference from Embodiment 1 is that the plastic frame 2 is provided in the first metal case 3 so as to be able to move up and down freely, and the free movement distance is D, and the high-voltage positive electrode dome 14 is further used to abut the plastic frame 2 against the top wall of the first metal case 3. By increasing the height of the low-voltage positive electrode cap 11 by 1 to 4 mm, the entire lithium battery of the present application becomes 1 to 4 mm longer than the conventional lithium battery. When it is installed in the battery chamber, since the low-voltage positive electrode cap 11 is compressed and shrunk, it does not affect the installation of the lithium battery, but the installation effect of the lithium battery becomes tighter. When the negative electrode elastic element in the battery chamber is deformed or has poor elasticity, the low-voltage positive electrode cap 11 only shrinks partially or does not shrink at all, thereby filling the space lacking the elasticity of the negative electrode elastic element in the battery chamber and ensuring good electrical contact.

[0035] In this embodiment, the low-voltage positive electrode cap 11 is attached to the plastic frame 2 via an adhesive, and the positive and negative electrode gaskets 17 are attached to the plastic frame 2 and the low-voltage positive electrode cap 11 via an adhesive. In this way, the low-voltage positive electrode cap 11, the plastic frame 2, and the entire voltage adjustment circuit assembly can move up and down together and will not come apart.

[0036] Referring to FIG. 15, the high-voltage positive electrode dome 14 needs to select appropriate elasticity and should have sufficient elastic force to push up the low-voltage positive electrode cap 11, the plastic frame 2, and the voltage adjustment circuit assembly 1. Also, the elastic force should not be too strong, as if the elastic force is too strong, it will be difficult to install in the battery chamber. In order to enable the plastic frame 2 to move freely up and down, and also to minimize the frictional force with the inner wall of the first metal case 3 as much as possible. Therefore, the present application is improved as follows. Firstly, a vertical guide strip 23 protruding from the outer peripheral surface of the plastic frame 2 is provided, and since the contact area between the two is greatly reduced, the frictional force with the inner wall of the first metal case 3 can be reduced. Secondly, a protrusion 151 protruding outward is provided on the negative electrode dome 15, and by the protrusion 151 contacting the inner wall of the first metal case 3, the contact area between the two can be similarly reduced, thereby reducing the frictional force with the inner wall of the first metal case 3. Other structures and beneficial effects are all the same as those in Embodiment 1, so detailed descriptions are omitted here.

[0037] Embodiment 3 Referring to FIGS. 17 to 20, the difference from Embodiment 2 is that the plastic frame 2 can not only move up and down within the first metal case 3 but also rotate within the first metal case 3. In this way, when the charging port 13 rotates at a certain angle, it will be hidden inside the first metal case 3, making the appearance of the lithium battery more beautiful, effectively protecting the charging port 13, and improving safety.

[0038] Referring to FIG. 20, the low-voltage positive electrode cap 11 is relatively smooth, small in volume, and not easy to manually screw. Therefore, in this embodiment, an annular tooth 24 located at the upper edge of the charging port 13 is provided on the upper frame 21 of the plastic frame 2. By moving the annular tooth 24, the plastic frame 2 rotates the charging port 13 to hide it. Usually, when the low-voltage positive electrode cap 11 is not compressed, the annular tooth 24 is not exposed. However, when the low-voltage positive electrode cap 11 is compressed, the annular tooth 24 moves downward and is exposed. At this time, it can be scraped with a claw, a toothpick, a screwdriver, etc., and the charging port 13 can be exposed or hidden, so as to achieve the above-described technical effects. The other structures and beneficial effects are all the same as those in Embodiment 2, so detailed descriptions are omitted here.

[0039] The above are all preferred embodiments of the present application, which do not limit the protection scope of the present application. Any equivalent changes made according to the structure, shape, and principle of the present application are all included within the protection scope of the present application.

Claims

Claim 1 A lithium secondary battery, comprising: a voltage regulation circuit assembly, a plastic frame, a first metal case, a lithium ion cell, and an insulating outer skin; the voltage regulation circuit assembly and the plastic frame are provided inside the first metal case, the plastic frame is used to fix the voltage regulation circuit assembly; the lithium ion cell includes a wound cell assembly, a high voltage positive electrode cap assembly, and a second metal case; an annular rolling slot is provided at the upper part of the second metal case; the wound cell assembly is provided inside the second metal case and is positionally restricted by the annular rolling slot; the second metal case is divided by the annular rolling slot into a lower main body part and an upper shrinking part; the outer diameter of the first metal case is the same as the outer diameter of the main body part of the second metal case; the inner diameter of the first metal case is the same as the outer diameter of the shrinking part of the second metal case; the shrinking part of the second metal case is embedded inside the first metal case, and the outer surfaces of the first metal case and the second metal case are flush; and the insulating outer skin covers the outside of the first metal case and the second metal case. A lithium secondary battery characterized by the above. Claim 2 The first metal case and the second metal case are fixedly connected by spot welding, or the lower edge of the first metal case shrinks inward to form a shrinking opening to define the shrinking part of the second metal case. The lithium secondary battery according to claim 1, characterized by the above. Claim 3 The voltage adjustment circuit assembly includes a low-voltage positive electrode cap, a PCB board, a charging port, a high-voltage positive electrode dome, a negative electrode dome, and an elastic ejector pin. The charging port, high-voltage positive electrode dome, negative electrode dome, and elastic ejector pin are all provided on the PCB board. The plastic frame and the low-voltage positive electrode cap are defined by the top wall of the first metal case. A positive and negative electrode gasket is further provided between the low-voltage positive electrode cap and the top wall of the first metal case. The first metal case is provided with a through hole at the top and a first charging escape hole on the side surface. The low-voltage positive electrode cap protrudes from the through hole. The charging escape hole is used to expose the charging port of the voltage adjustment circuit assembly. The elastic ejector pin abuts against the inner wall of the low-voltage positive electrode cap. The negative electrode dome abuts against the inner wall of the first metal case. The high-voltage positive electrode dome abuts against the high-voltage positive electrode cap assembly. The first metal case and the second metal case are in contact and conductive. A second charging escape hole is provided at a position corresponding to the side surface of the insulating outer skin. The lithium secondary battery according to claim 1, characterized in that

4. The plastic frame includes an upper frame and a lower frame that are fastened. The PCB board is fixed between the upper frame and the lower frame. The lithium secondary battery according to claim 3, characterized in that

5. The plastic frame is attached to the inner wall of the first metal case via an adhesive. The lithium secondary battery according to claim 3, characterized in that

6. The plastic frame is provided in the first metal case so as to be vertically movable. The high-voltage positive electrode dome is further used to abut the plastic frame against the top wall of the first metal case. The lithium secondary battery according to claim 3, characterized in that

7. The low-voltage positive electrode cap is attached to the plastic frame via an adhesive. The positive and negative electrode gasket is attached to the plastic frame and the low-voltage positive electrode cap via an adhesive. The lithium secondary battery according to claim 6, characterized in that

8. A protruding vertical guide strip for reducing the frictional force with the inner wall of the first metal case is provided on the outer peripheral surface of the plastic frame. The lithium secondary battery according to claim 6, characterized in that

9. The negative electrode dome is provided with protrusions protruding outward, and by contacting the inner wall of the first metal case through the protrusions, the frictional force with the inner wall of the first metal case is reduced. The lithium secondary battery according to claim 6, characterized in that.

10. A method for manufacturing a lithium secondary battery according to any one of claims 1 to 9, comprising: Placing the wound cell assembly in a second metal case, creating an annular rolling slot at the upper part of the second metal case, welding the negative electrode tag of the wound cell assembly to the bottom wall of the second metal case, welding the positive electrode tag to the high-voltage positive electrode cap assembly, injecting an electrolytic solution, placing the high-voltage positive electrode cap assembly in the second metal case, creating a contraction part at the upper part of the second metal case, and creating a spinning edge at the upper edge of the second metal case, fixing the high-voltage positive electrode cap assembly in the contraction part to form a lithium ion cell, and performing formation and capacity grading on the lithium ion cell, step S1; After fixing the voltage adjustment circuit assembly to the plastic frame, incorporating it together into the first metal case, step S2; Embedding the upper end of the lithium ion cell into the first metal case, step S3; Coating with an insulating outer skin, performing heat shrinkage, and wrapping the insulating outer skin around the first metal case and the lithium ion cell, step S4. A method for manufacturing a lithium secondary battery, characterized in that it includes.

Images