Novel helium detection process

Abstract

The invention belongs to the technical field of a secondary helium detection process of a cylindrical battery, and particularly relates to a novel helium detection process which comprises the following steps: step 1, carrying out a secondary liquid injection process on the cylindrical battery along a logistics line, and introducing helium after the secondary liquid injection of the cylindrical battery; step 2, placing a helium plug at a 5mm liquid injection hole of a battery cell positive electrode collector plate of the cylindrical battery; 3, after the helium plug is in place, identifying and positioning through equipment, puncturing the helium plug from top to bottom by a manipulator with a steel needle, and quickly pulling out the steel needle; step 5, placing a positive electrode sealing sheet for pressing, and welding the positive electrode sealing sheet and a battery cell positive electrode collector plate of the cylindrical battery from the top or the side edge through laser welding to finish the final sealing of the cylindrical battery; and step 6, enabling the cylindrical battery to flow into a helium detection process along the logistics line. According to the invention, while the traditional helium detection process design is optimized, the detection rate of secondary helium detection can be increased and decreased, the risk that a leakage battery flows to the market and a terminal user is reduced, and an effective solution is provided for the detection scheme of a battery cell.

Description

Technical Field

[0001] The invention belongs to the technical field of secondary helium inspection process of cylindrical batteries, and specifically relates to a novel helium inspection process. Background Art

[0002] With the continuous development and deepening of the lithium battery industry, the huge demand in the field of energy storage, and the requirement of low-cost large-scale products, the traditional secondary helium inspection process and the realization of electrolyte molecule detection all require filling helium and inserting glue nails at the injection port to perform secondary helium inspection. For example, in the prior art, a lithium-ion battery airtightness detection method disclosed in patent number CN111504561A is characterized in that it includes the following steps: directly nailing the injection port of a lithium-ion battery with a qualified secondary injection amount, welding a sealing sheet to seal it; after the sealing sheet position of the sealed lithium-ion battery is filled with helium at a positive pressure, The lithium-ion battery is transferred into the detection chamber for helium content detection. At present, the method of detecting leakage at the production site is usually to return helium after secondary liquid injection. The liquid injection is completed by filling helium to restore normal pressure. Batteries with qualified liquid injection volume are installed with glue nails, laser sealed and welded, and then helium tested. This method has the risk of missed judgments and misjudgments. When checking the leakage rate of the sealing nail welding, sometimes the helium cannot penetrate out due to the insertion of glue nails in the liquid injection port. The secondary helium test cannot detect the slightly leaking battery, resulting in the leakage of the battery into the market. There is a great safety hazard, which is one of the major problems that hinder the improvement of the qualified rate. For this reason, we propose a new helium detection process. Summary of the invention

[0003] The purpose of the present invention is to provide a novel helium inspection process. In order to prevent the problem in the prior art that the liquid injection port is inserted with a glue nail so that helium cannot penetrate outward, a helium plug is provided for sealing, and a steel needle is used to quickly pierce the helium plug, and a positive electrode sealing sheet is quickly inserted and pressed tightly, and the positive electrode sealing sheet and the positive electrode current collector of the cylindrical battery cell are welded together from the top or the side by laser welding, so that in the final helium inspection process, the sealed cylindrical battery is placed in a sealed cavity, and the sealed cavity is evacuated. If leakage occurs and the sealing is not thorough, helium leaks out from the through hole pierced in the middle of the helium plug and is detected by a helium detection device, so that when it is judged that the cylindrical battery has a helium leak, the cylindrical battery has a leak and is an unqualified product, and a secondary helium inspection is completed.

[0004] The technical solution adopted by the present invention is as follows:

[0005] A novel helium detection process includes the following steps:

[0006] Step 1: The cylindrical battery undergoes a secondary liquid injection process along the logistics line, and helium is introduced after the secondary liquid injection of the cylindrical battery;

[0007] Step 2: Place a helium plug at the 5mm injection hole of the positive electrode collector of the cylindrical battery cell;

[0008] Step 3: After the helium plug is in place, the device identifies and locates it, and the manipulator with a steel needle pierces the helium plug from top to bottom and quickly pulls out the steel needle;

[0009] Step 5: Put in the positive electrode sealing sheet and press it tightly, and weld the positive electrode sealing sheet and the positive electrode current collector of the cylindrical battery cell together from the top or side by laser welding to complete the final sealing of the cylindrical battery;

[0010] Step 6: The cylindrical batteries flow into the helium inspection process along the logistics line.

[0011] Preferably, the cylindrical battery further comprises an aluminum shell, a winding core is provided inside the aluminum shell, a central tube is provided in the winding core, and the aluminum shell and the upper end of the central tube are connected to the positive electrode collector disk.

[0012] Preferably, the central tube is aligned with the liquid injection hole, and the helium plug is inserted into the upper port of the central tube from the liquid injection hole.

[0013] Preferably, the helium plug has a three-section structure, the diameter of the upper plug portion of the helium plug is 6 mm, the height of the upper plug portion of the helium plug is 1 mm, the diameter of the middle plug portion of the helium plug is 4.8 mm, the height of the middle plug portion of the helium plug is 3.23 mm, the inner diameter of the lower plug portion of the helium plug is 3 mm, and the height of the lower plug portion of the helium plug is 2.8 mm.

[0014] Preferably, the device identification and positioning in step 3 adopts a CCD industrial camera identification and positioning system.

[0015] Preferably, the positive electrode sealing sheet includes an outer ring portion and an inner ring portion, and the inner and outer peripheries of the lower edge of the outer ring portion are provided with step portions, and the step portion of the outer periphery of the lower edge of the outer ring portion is adapted to the positive electrode current collecting plate, the outer diameter of the outer ring portion is 46 mm, the width of the step portion of the outer periphery of the lower edge of the outer ring portion is 4.1 mm, the width of the step portion of the inner periphery of the lower edge of the outer ring portion is 3 mm, and the inner diameter of the outer ring portion is 8 mm.

[0016] Preferably, an outer connecting ring is provided on the side of the inner ring portion, the connecting ring is fitted with a step portion provided on the inner periphery of the lower edge of the outer ring portion, the middle portion of the inner ring portion is convex, and the inner ring portion is located directly above the helium plug.

[0017] Preferably, the helium inspection process in step 6 is to place the sealed cylindrical battery into a sealed cavity, evacuate the sealed cavity, and then determine whether there is helium leakage in the cylindrical battery to complete the secondary helium inspection.

[0018] The technical effects achieved by the present invention are:

[0019] In the present invention, in order to prevent the problem that the helium cannot penetrate outward due to the insertion of the glue nail in the liquid filling port in the prior art, a helium plug is provided for sealing, and a steel needle is used to quickly puncture the helium plug, and the positive electrode sealing sheet is quickly inserted and pressed, and the positive electrode sealing sheet and the positive electrode current collector of the cylindrical battery are welded together from the top or the side by laser welding, so that in the final helium inspection process, the sealed cylindrical battery is placed in the sealed cavity, and the sealed cavity is evacuated. If leakage occurs and the sealing is not thorough, helium leaks out from the through hole punctured in the middle of the helium plug and is detected by the helium detection device, so that when it is judged that the cylindrical battery has helium leakage, the cylindrical battery has leakage and is an unqualified product, and a secondary helium inspection is completed. The present invention can increase or decrease the detection rate of the secondary helium inspection while optimizing the traditional helium inspection process design, reduce the risk of leaking batteries flowing to the market and end users, and provide an effective solution for the detection scheme of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a flow chart of a novel helium detection process of the present invention;

[0021] Figure 2 It is a diagram of the cylindrical battery, helium plug, positive electrode sealing sheet and steel needle adaptation in the present invention;

[0022] Figure 3 is a cross-sectional view of a cylindrical battery in the present invention;

[0023] Figure 4 is a cross-sectional view of the positive electrode sealing sheet of the present invention;

[0024] Figure 5 It is a cross-sectional view of the helium plug in the present invention.

[0025] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0026] 1. Cylindrical battery; 2. Helium plug; 3. Steel needle; 4. Positive electrode sealing sheet; 101. Positive electrode current collecting plate; 102. Liquid injection hole; 103. Aluminum shell; 104. Winding core; 105. Center tube; 201. Upper end plug; 202. Middle plug; 203. Lower end plug; 401. Outer ring; 402. Inner ring; 403. Connecting ring; 404. Step. DETAILED DESCRIPTION

[0027] In order to make the purpose and advantages of the present invention more clearly understood, the present invention is specifically described below in conjunction with embodiments. It should be understood that the following text is only used to describe one or several specific embodiments of the present invention, and does not strictly limit the scope of protection of the specific claims of the present invention.

[0028] like Figure 1-5As shown, a novel helium detection process includes the following steps:

[0029] Step 1: The cylindrical battery 1 is subjected to a secondary liquid injection process along the logistics line, and helium is introduced after the secondary liquid injection of the cylindrical battery 1;

[0030] Step 2: Place a helium plug 2 at the 5 mm injection hole 102 of the positive electrode current collecting disk 101 of the cylindrical battery 1;

[0031] Step 3: After the helium plug 2 is in place, the device identifies and locates it, and the manipulator with a steel needle 3 pierces the helium plug 2 from top to bottom, and quickly pulls out the steel needle 3;

[0032] Step 5: Place the positive electrode sealing sheet 4 and press it tightly, and weld the positive electrode sealing sheet 4 and the positive electrode current collecting plate 101 of the cylindrical battery 1 together from the top or side by laser welding to complete the final sealing of the cylindrical battery 1;

[0033] Step 6: The cylindrical battery 1 flows into the helium inspection process along the logistics line.

[0034] like Figure 1-5 As shown, in the present invention, in order to prevent the problem that the helium cannot penetrate outward due to the insertion of the glue nail in the liquid filling port in the prior art, a helium plug 2 is provided for sealing, and a steel needle 3 is used to quickly pierce the helium plug 2, and the positive electrode sealing sheet 4 is quickly inserted and pressed, and the positive electrode sealing sheet 4 and the positive electrode current collecting plate 101 of the cylindrical battery 1 are welded together from the top or the side by laser welding, so that in the final helium inspection process, the sealed cylindrical battery 1 is placed in the sealed cavity, and the sealed cavity is evacuated. If leakage occurs and the sealing is not thorough, helium leaks out from the through hole pierced in the middle of the helium plug 2 and is detected by the helium detection device, so that when it is judged that the cylindrical battery 1 has a helium leak, the cylindrical battery 1 has a leak and is an unqualified product, and a secondary helium inspection is completed. While optimizing the traditional helium inspection process design, the present invention can increase or decrease the detection rate of the secondary helium inspection, reduce the risk of leaking batteries flowing to the market and end users, and provide an effective solution for the detection scheme of the battery cell.

[0035] like Figure 1 As shown, the cylindrical battery 1 also includes an aluminum shell 103, a winding core 104 is provided inside the aluminum shell 103, a central tube 105 is provided in the winding core 104, the aluminum shell 103 and the upper end of the central tube 105 are connected to the positive electrode collecting plate 101; the central tube 105 is aligned with the injection hole 102, and the helium plug 2 is inserted into the upper end of the central tube 105 from the injection hole 102.

[0036] like Figure 5As shown, the helium plug 2 has a three-section structure, the upper end plug portion 201 of the helium plug 2 has a diameter of 6 mm, the upper end plug portion 201 of the helium plug 2 has a height of 1 mm, the middle plug portion 202 of the helium plug 2 has a diameter of 4.8 mm, the middle plug portion 202 of the helium plug 2 has a height of 3.23 mm, the lower end plug portion 203 of the helium plug 2 has an inner diameter of 3 mm, and the lower end plug portion 203 of the helium plug 2 has a height of 2.8 mm.

[0037] like Figure 2 As shown, in the present invention, by providing a helium plug 2, the helium plug 2 can fully seal the helium injected after the secondary liquid injection and prevent it from leaking, thereby providing a guarantee for detecting whether there is a helium leakage after the helium plug 2 is subsequently punctured. If the helium plug 3 is not used, the helium injected after the secondary liquid injection will leak quickly when the positive electrode sealing sheet 4 is welded. In subsequent detections, if the battery sealing effect is poor, no helium leakage can be detected either, because at this time there is no helium or only a small amount of helium in the cylindrical battery 1, which ultimately causes a false detection. In summary, by providing the helium plug 2, the accuracy of the detection is greatly improved.

[0038] The device identification and positioning in step 3 adopts a CCD industrial camera identification and positioning system. By using the CCD industrial camera identification and positioning system, the positioning is made more accurate. The manipulator is equipped with a steel needle 3 to accurately pierce the helium plug 2 from top to bottom.

[0039] like Figure 4 As shown, the positive electrode sealing sheet 4 includes an outer ring portion 401 and an inner ring portion 402. The inner and outer peripheries of the lower edge of the outer ring portion 401 are provided with step portions 404. The step portion 404 on the outer periphery of the lower edge of the outer ring portion 401 is adapted to the positive electrode current collecting plate 101. The outer diameter of the outer ring portion 401 is 46 mm, the width of the step portion 404 on the outer periphery of the lower edge of the outer ring portion 401 is 4.1 mm, the width of the step portion 404 on the inner periphery of the lower edge of the outer ring portion 401 is 3 mm, and the inner diameter of the outer ring portion 401 is 8 mm. An outer connecting ring 403 is provided on the side of the inner ring portion 402. The connecting ring 403 and the step portion 404 on the inner periphery of the lower edge of the outer ring portion 401 are fitted together. The middle part of the inner ring portion 402 is convex, and the inner ring portion 402 is located directly above the helium plug 2.

[0040] like Figure 2 As shown, in the present invention, since the inner and outer peripheries of the lower edge of the outer ring portion 401 are provided with step portions 404, the step portion 404 of the outer periphery of the lower edge of the outer ring portion 401 is adapted to the positive electrode collector 101, so that the positive electrode sealing sheet 4 and the positive electrode collector 101 of the cylindrical battery cell can be welded together from the top or the side by laser welding, and the welding result is more accurate, which further avoids the occurrence of defective products caused by welding errors of the positive electrode sealing sheet 4, and further improves the qualified rate of the product.

[0041] The helium inspection process in step 6 is to place the sealed cylindrical battery 1 into a sealed cavity, evacuate the sealed cavity, and determine whether there is helium leakage in the cylindrical battery 1 to complete the secondary helium inspection.

[0042] The above is only a preferred embodiment of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principles of the present invention, and these improvements and modifications should also be considered as the protection scope of the present invention. The structures, devices and operating methods not specifically described and explained in the present invention shall be implemented according to the conventional means in the art unless otherwise specified and limited.

Claims

1. A new helium detection process, characterized in that: The following steps are involved: Step 1: The cylindrical battery (1) undergoes a secondary liquid injection process along the logistics line, and helium is introduced into the cylindrical battery (1) after the secondary liquid injection; Step 2: Place a helium plug (2) at the 5 mm injection hole (102) of the positive electrode current collecting plate (101) of the cylindrical battery (1); Step 3: After the helium plug (2) is in place, the device identifies and locates it, and the manipulator with a steel needle (3) pierces the helium plug (2) from top to bottom, and quickly pulls out the steel needle (3); Step 5: insert the positive electrode sealing sheet (4) and press it tightly, and weld the positive electrode sealing sheet (4) and the positive electrode current collecting plate (101) of the cylindrical battery (1) together from the top or the side by laser welding to complete the final sealing of the cylindrical battery (1); Step 6: The cylindrical battery (1) flows into the helium inspection process along the logistics line.

2. A novel helium detection process according to claim 1, characterized in that: The cylindrical battery (1) further comprises an aluminum shell (103), a winding core (104) is provided inside the aluminum shell (103), a central tube (105) is provided in the winding core (104), and the upper ends of the aluminum shell (103) and the central tube (105) are connected to the positive electrode current collecting disk (101).

3. A novel helium detection process according to claim 1, characterized in that: The central tube (105) is aligned with the liquid injection hole (102), and the helium plug (2) is inserted into the upper end of the central tube (105) from the liquid injection hole (102).

4. A novel helium detection process according to claim 1, characterized in that: The helium plug (2) is a three-stage structure. The diameter of the upper plug portion (201) of the helium plug (2) is 6 mm, the height of the upper plug portion (201) of the helium plug (2) is 1 mm, the diameter of the middle plug portion (202) of the helium plug (2) is 4.8 mm, the height of the middle plug portion (202) of the helium plug (2) is 3.23 mm, the inner diameter of the lower plug portion (203) of the helium plug (2) is 3 mm, and the height of the lower plug portion (203) of the helium plug (2) is 2.8 mm.

5. A novel helium detection process according to claim 1, characterized in that: The device identification and positioning in step 3 adopts a CCD industrial camera identification and positioning system.

6. A novel helium detection process according to claim 1, characterized in that: The positive electrode sealing sheet (4) comprises an outer ring portion (401) and an inner ring portion (402); the inner and outer peripheries of the lower edge of the outer ring portion (401) are provided with step portions (404); the step portion (404) on the outer periphery of the lower edge of the outer ring portion (401) is adapted to the positive electrode current collecting plate (101); the outer diameter of the outer ring portion (401) is 46 mm; the width of the step portion (404) on the outer periphery of the lower edge of the outer ring portion (401) is 4.1 mm; the width of the step portion (404) on the inner periphery of the lower edge of the outer ring portion (401) is 3 mm; and the inner diameter of the outer ring portion (401) is 8 mm.

7. A novel helium detection process according to claim 1, characterized in that: An outer connecting ring (403) is provided on the side of the inner ring portion (402), and the connecting ring (403) is in contact with a step portion (404) provided on the inner periphery of the lower edge of the outer ring portion (401). The middle portion of the inner ring portion (402) is raised, and the inner ring portion (402) is located directly above the helium plug (2).

8. A novel helium detection process according to claim 1, characterized in that: The helium inspection process in step 6 is to place the sealed cylindrical battery (1) into a sealed cavity, evacuate the sealed cavity, and determine whether the cylindrical battery (1) has helium leakage, thereby completing a secondary helium inspection.

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