Method and device for charging and discharging battery after CID flip

Abstract

The application discloses a method for charging and discharging a battery CID after CID turning over again, which comprises the following steps: S1, cap disassembly, disassembling the cap of a cycle invalidation battery cell, and stripping the positive electrode lug welded on the cap; S2, lug welding, using a spot welding device to directly weld an external positive electrode lug on the original positive electrode lug, and welding an external negative electrode lug on the steel shell negative electrode end through soldering; S3, plastic aluminum film sealing, folding the plastic aluminum film in half, placing the battery cell between the double-layer plastic aluminum film, the top seal at both ends being the positive and negative electrode lug leading ends, and the side edge being a side seal, after supplementing the electrolyte into the battery cell, vacuumizing and then sealing the plastic aluminum film; and S4, retesting, performing small current calibration and cycle test on the resealed battery cell. The application provides a method for charging and discharging a battery CID after CID turning over again, which can charge and discharge the battery CID after CID turning over again without disassembling the steel shell. The application also provides a device for charging and discharging a battery CID after CID turning over again.

Description

Technical Field

[0001] This invention relates to the field of battery testing technology, and in particular to a method and apparatus for recharging and discharging a battery after its CID is flipped. Background Technology

[0002] During the design and development of cylindrical lithium-ion batteries, charge-discharge experiments are conducted under certain conditions to verify the battery's long-term cycle performance. Inevitably, excessive current may occur, leading to severe gas generation and causing the current interruption device (CID) to flip. Since the battery cannot be subjected to any further charge-discharge tests after the CID flips, failure analysis, such as low-current calibration and electrolyte replenishment, can only be performed by disassembling and reassembling the battery from its steel casing, or by using the core with the steel casing removed to fabricate a pouch battery.

[0003] However, there are certain dangers in removing the steel casing. This is because the battery may be fully charged when the CID is flipped. Due to the severe deformation of the core after long-term cycling, the steel casing can easily scratch the core during disassembly, causing a short circuit and explosion in the fully charged core. At the same time, removing the steel casing from a cylindrical battery will cause severe tearing of the negative electrode tab, which is not conducive to re-welding the tab to prepare a pouch battery. At this time, the fully charged core will also be completely exposed to the air. The entire assembly process has certain safety hazards. Summary of the Invention

[0004] The purpose of this invention is to provide a method for recharging and discharging a battery after flipping its CID, which allows the battery to be recharged and discharged without disassembling the steel casing.

[0005] The technical solution adopted by the method and apparatus for recharging and discharging a battery after CID flipping disclosed in this invention is as follows:

[0006] A method for recharging and discharging a battery after its CID has been flipped includes the following steps:

[0007] S1, Cap Disassembly: Disassemble the cap of the cycle-failed cell that has already flipped the CID. Use disassembly tools to slowly separate the cap from the whole battery and peel off the positive electrode tab welded to the cap to ensure the integrity of the positive electrode tab.

[0008] S2, tab welding: Using a spot welding device, the failed battery cell with the cap removed is re-welded with a new positive tab. The external positive tab is directly welded to the original positive tab, while the external negative tab is soldered to the negative end of the steel shell.

[0009] S3 aluminum-plastic film sealing: Fold the aluminum-plastic film in half, place the battery cell between the two layers of aluminum-plastic film, package the battery cell with the positive and negative tabs already welded, and seal the top and side openings. When sealing the aluminum-plastic film, the two ends are the top seals, and the top seals at both ends are the positive and negative tab lead-out ends. The sides are the side seals. After adding electrolyte to the battery cell, vacuum is drawn and the aluminum-plastic film is then side-sealed.

[0010] S4, Retest: Perform low-current calibration and cycle testing on the re-sealed battery cell to accurately obtain the true capacity value of the battery cell after cycle failure.

[0011] As a preferred embodiment, the external positive electrode tab is an aluminum strip, and the external negative electrode tab is a copper-nickel strip.

[0012] As a preferred embodiment, the dimensions of the external positive electrode tab are 0.1mm*4mm*60mm, and the dimensions of the external negative electrode tab are 0.1mm*4mm*60mm.

[0013] As a preferred embodiment, the aluminum-plastic film has a size of 20cm*20cm.

[0014] As a preferred embodiment, in step S3, the amount of electrolyte added is 1g, and the vacuum degree is <0.1Kpa.

[0015] As a preferred option, in step S4, a small current of 0.05C is used for cell calibration.

[0016] A device for recharging and discharging a battery after its CID is flipped includes a folded aluminum-plastic film, in which a failed battery cell with its cap removed is wrapped. The positive and negative tabs at both ends of the failed battery cell extend out of the aluminum-plastic film, and the sides of the aluminum-plastic film are vacuum-sealed to form a closed vacuum cavity inside the aluminum-plastic film.

[0017] As a preferred embodiment, the failed battery cell is extended by using external positive and external negative tabs, wherein the external positive tab is made of aluminum strip and the external negative tab is made of copper-nickel strip.

[0018] As a preferred embodiment, the failed battery cell is further treated with electrolyte replenishment.

[0019] As a preferred embodiment, the failed battery cell is located in the middle of the aluminum-plastic film.

[0020] The beneficial effect of the method for recharging and discharging a battery after CID flipping disclosed in this invention is as follows: by removing the cap of the battery whose CID has flipped after long-term cycling, retaining a certain length of the positive tab, connecting the positive and negative tabs externally, and resealing it with an aluminum-plastic film to form an internal seal, the original internal sealed conditions of the battery cell are simulated. Then, a vacuum treatment is performed, and by measuring the external positive and negative tabs that extend out of the aluminum-plastic film, normal charging and discharging can be carried out. Thus, the battery CID can be flipped and recharged and discharged without disassembling the steel shell. Attached Figure Description

[0021] Figure 1 This is a flowchart of a method for recharging and discharging a battery after its CID is flipped according to the present invention.

[0022] Figure 2 This is a cyclic data diagram of the failed battery cell before and after resealing, based on a method for recharging and discharging a battery after CID flipping according to the present invention.

[0023] Figure 3 This is a schematic diagram of the structure of a device for recharging and discharging a battery after its CID is flipped according to the present invention. Detailed Implementation

[0024] The present invention will be further described and illustrated below with reference to specific embodiments and the accompanying drawings:

[0025] Please refer to Figure 1 A method for recharging and discharging a battery after its CID has been flipped, comprising the following steps:

[0026] S1, Cap Disassembly: Disassemble the cap of the cycle-failed cell that has already flipped the CID. Use disassembly tools to slowly separate the cap from the whole battery and peel off the positive electrode tab welded to the cap to ensure the integrity of the positive electrode tab.

[0027] S2, tab welding: Using a spot welding device, the failed battery cell with the cap removed is re-welded with a new positive tab. The external positive tab is directly welded to the original positive tab, while the external negative tab is soldered to the negative end of the steel shell.

[0028] S3 aluminum-plastic film sealing: Fold the aluminum-plastic film in half. The size of the aluminum-plastic film is 20cm*20cm. Place the battery cell between the two layers of aluminum-plastic film. Package the battery cell with the positive and negative tabs already soldered and seal it from the top and side. When sealing the aluminum-plastic film, the two ends are the top seals, and the top seals at both ends are the positive and negative tab lead-out ends. The sides are the side seals. After adding 1g of electrolyte to the battery cell, vacuum is drawn and the aluminum-plastic film is then side-sealed. The vacuum degree is <0.1Kpa.

[0029] S4, Retest: Perform a 0.05C low-current calibration and cycle test on the resealed battery cell to accurately obtain the true capacity value of the battery cell after cycle failure.

[0030] Please refer to Figure 2 By removing the cap of a battery whose CID has been flipped after long-term cycling, leaving a certain length of the positive tab, and connecting external positive and negative tabs, and then resealing it with an aluminum-plastic film to form an internal seal, the original internal sealed conditions of the battery cell are simulated. After vacuuming, the external positive and negative tabs extending out of the aluminum-plastic film can be measured to allow normal charging and discharging. Thus, the battery CID can be flipped and charged and discharged again without removing the steel casing.

[0031] In the above scheme, the external positive electrode tab is an aluminum strip, the external negative electrode tab is a copper-nickel strip, and the dimensions of the external positive electrode tab are 0.1mm*4mm*60mm and the dimensions of the external negative electrode tab are 0.1mm*4mm*60mm.

[0032] Please refer to Figure 3 A device for recharging and discharging a battery after its CID is flipped includes a folded aluminum-plastic film 10, inside which is wrapped a failed battery cell 20 whose cap has been peeled off. The positive electrode tab 21 and negative electrode tab 22 at both ends of the failed battery cell 20 extend out of the aluminum-plastic film 10, and the sides of the aluminum-plastic film 10 are vacuum-sealed to form a closed vacuum cavity inside the aluminum-plastic film 10.

[0033] The failed battery cell 20 is extended by external positive tab 23 and external negative tab 24. The external positive tab 2321 uses a new positive tab 21 made of aluminum strip and a new negative tab 22 made of copper-nickel strip. The failed battery cell 20 is also treated with electrolyte replenishment. The failed battery cell 20 is located in the middle of the aluminum-plastic film 10.

[0034] This invention provides a method for recharging and discharging a battery after its CID has been flipped. The method involves removing the cap of a battery whose CID has been flipped after long-term cycling, retaining a certain length of the positive tab, connecting external positive and negative tabs, and then resealing the external tabs with an aluminum-plastic film to create an internal seal. This simulates the original sealed conditions of the battery cell. After vacuuming, the external positive and negative tabs extending out of the aluminum-plastic film are measured to allow for normal charging and discharging. Thus, the battery can be recharged and discharged after its CID has been flipped without disassembling the steel casing.

[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A method for charging and discharging a battery after CID flip, characterized in that, It comprises the following steps: S1, cap disassembly, the cycle failure battery cell whose cap has been turned over is disassembled, the cap is slowly separated from the whole battery using disassembly tools, and the positive electrode ear welded on the cap is peeled off to ensure the integrity of the positive electrode ear; S2, the positive electrode ear welding, using a point bottom welding device, the failure battery cell whose cap has been peeled off is welded with a new positive electrode ear, the external positive electrode ear is directly welded on the original positive electrode ear, and the external negative electrode ear is welded on the steel shell negative electrode through soldering; S3, the aluminum plastic film sealing, the aluminum plastic film is folded, the battery cell is placed between the double-layer aluminum plastic film, the battery cell whose positive and negative electrode ears have been welded is packaged and top sealed, when the aluminum plastic film is sealed, the two ends are top sealed, the top of the two ends is the positive and negative electrode ear lead-out end, and the side edge is side sealed, after the electrolyte is supplemented in the battery cell, the aluminum plastic film is side sealed after vacuumizing; S4, retesting, the resealed battery cell is subjected to 0.05C small current calibration and cycle test to accurately obtain the real capacity value of the battery cell after cycle failure.

2. The method for recharging and discharging a battery after flipping its CID as described in claim 1, characterized in that, The external positive electrode ear is an aluminum strip, and the external negative electrode ear is a copper-nickel strip.

3. The method of claim 2, wherein the battery CID is flipped over and recharged and discharged. The size of the external positive electrode ear is 0.1mm*4mm*60mm, and the size of the external negative electrode ear is 0.1mm*4mm*60mm.

4. The method of claim 1, wherein the battery CID is flipped over and recharged and discharged again. The size of the aluminum plastic film is 20cm*20cm.

5. The method of claim 1, wherein the battery CID is flipped over and recharged and discharged. In step S3, the supplemented electrolyte is 1g, and the vacuum degree is less than 0.1Kpa.

6. A device for recharging and discharging a battery after CID flipping for the method as claimed in claim 1, characterized in that, The aluminum plastic film is folded, the failure battery cell whose cap has been peeled off is wrapped in the aluminum plastic film, the positive and negative electrode ears at both ends of the failure battery cell extend out of the aluminum plastic film, and the side edges of the aluminum plastic film are vacuum sealed to form a closed vacuum cavity inside the aluminum plastic film.

7. A device for recharging and discharging a battery after CID flip as claimed in claim 6, wherein, The failure battery cell is extended by the external positive and negative electrode ears.

8. A device for recharging and discharging a battery after CID rollover as defined in claim 6, wherein, The failure battery cell is also subjected to electrolyte supplementing treatment.

9. A device for recharging and discharging a battery after CID flip as claimed in claim 8, wherein, The failure battery cell is located in the middle of the aluminum plastic film.

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