Coating repairing method, battery cell shell and battery cell

Abstract

The invention provides a coating repairing method, a battery cell shell and a battery cell, and relates to the technical field of coating repairing, and the coating repairing method comprises the following steps: laser is adopted to at least carry out treatment on a coating corresponding to a bad area or all coatings on the surface of a base material, and a to-be-repaired area is obtained; wherein the defocusing amount of the laser is + / -2mm; and the to-be-repaired area is coated with a repairing coating, and the to-be-repaired area is repaired. According to the coating repairing method provided by the embodiment of the invention, the purpose of removing the coating can be achieved, the energy of the laser cannot be excessively dispersed, the removing efficiency of the coating is improved, the difficulty of removing the coating from the surface of the base material is reduced, and the repairing process is simplified.

Description

Technical Field

[0001] The present application relates to the technical field of coating repair, and in particular to a coating repair method, a battery cell shell, and a battery cell. Background Art

[0002] In order to ensure the safety and durability of the battery cell, an insulating layer is usually set on the surface of the battery cell shell. The insulating layer mainly includes PET (polyethylene terephthalate) outer blue film and coating. Compared with the form of PET outer blue film, the coating has better process stability and can provide better insulation protection performance. However, when the insulating layer needs to be reworked and repaired, since the coating is tightly attached to the surface of the battery cell shell, it is difficult to peel off the coating from the surface of the battery cell shell, and the repair is more difficult. Summary of the invention

[0003] The embodiments of the present application provide a method for repairing a coating in a battery cell shell, a battery cell shell, and a battery cell, which can reduce the difficulty of peeling the coating from the surface of the battery cell shell and simplify the repair process.

[0004] In a first aspect, an embodiment of the present application provides a coating repair method, comprising:

[0005] The coating corresponding to at least the defective area is processed by laser to obtain the area to be repaired; wherein the defocus amount of the laser is ±2 mm;

[0006] A repair coating is applied to the area to be repaired, and the area to be repaired is repaired.

[0007] In some embodiments, during the laser treatment of the coating, the temperature rise of the substrate surface is ≤60°C.

[0008] In some embodiments, laser processing is used to process at least the coating corresponding to the defective area, including:

[0009] Under a protective atmosphere, at least the coating corresponding to the defective area is processed by laser.

[0010] In some embodiments, laser is used to process at least the coating corresponding to the defective area, including:

[0011] Applying laser to the contact surface between the substrate and the coating so that the substrate is separated from at least the coating corresponding to the defective area;

[0012] The coating is peeled off from the substrate surface.

[0013] In some embodiments, the power of the laser is 500 W or less.

[0014] In some embodiments, after stripping the coating from the surface of the substrate, the method further comprises:

[0015] The substrate surface is cleaned to remove carbides on the substrate surface.

[0016] In some embodiments, applying a laser to the contact surface between the substrate and the coating so as to separate the substrate from at least the coating corresponding to the defective area comprises:

[0017] The laser is applied to the contact surface between the substrate and the coating, so that the substrate and all the coatings on the substrate surface are separated from each other.

[0018] In some embodiments, laser is used to process at least the coating corresponding to the defective area, including:

[0019] The laser is applied to at least the coating corresponding to the defective area to vaporize at least the coating corresponding to the defective area, so as to remove at least the coating corresponding to the defective area from the surface of the substrate.

[0020] In some embodiments, the laser has a power of 500-1500W.

[0021] In some embodiments, repairing the area to be repaired includes:

[0022] Identify the area to be repaired and apply the repair coating to the area to be repaired;

[0023] The repair coating has the same thickness as the coating.

[0024] In some embodiments, repairing the area to be repaired includes:

[0025] Identify the area to be repaired, and apply a repair coating on the area to be repaired and on the circumference of the edge of the area to be repaired, so that the repair coating is formed on the area to be repaired, and a coating overlapping area is formed on the circumference of the edge of the area to be repaired;

[0026] The thickness of the coating is T1, the thickness of the overlapping area of ​​the coating is T2, and 0.5T1≤T2≤2T1.

[0027] In some embodiments, the defective area includes at least one of a damaged area, an uneven thickness area, a bulging area, a bubble area, a peeling area, and a deformed area.

[0028] In some embodiments, when the defective area includes a damaged area or a peeling area, a laser is applied to at least the coating corresponding to the defective area to vaporize at least the coating corresponding to the defective area, so as to remove at least the coating corresponding to the defective area from the surface of the substrate;

[0029] When the defective area includes at least one of an uneven thickness area, a bulging area, a blistering area and a deformed area, a laser is applied to the contact surface between the substrate and the coating to separate the substrate from at least the coating corresponding to the defective area.

[0030] In some embodiments, before using laser to treat at least the coating corresponding to the defective area on the surface of the substrate, the method further includes:

[0031] Obtain the area of ​​the defective area and the total area of ​​all coatings on the substrate surface;

[0032] According to the area of ​​the defective area and the total area of ​​all coatings on the surface of the substrate, a ratio of the area of ​​the defective area to the total area of ​​all coatings on the surface of the substrate is obtained;

[0033] When the ratio is less than or equal to 30%, the coating corresponding to the defective area is removed by laser;

[0034] When the ratio is greater than 30%, the laser is used to remove all coatings on the surface of the substrate.

[0035] In some embodiments, the protective atmosphere is a nitrogen atmosphere.

[0036] In a second aspect, an embodiment of the present application provides a battery cell shell, which is repaired using the above coating repair method.

[0037] In a third aspect, an embodiment of the present application provides a battery cell, comprising the battery cell shell as described above.

[0038] Beneficial effects of the embodiments of the present application:

[0039] In the coating repair method provided in the embodiment of the present application, a laser is used to process at least the coating corresponding to the defective area to obtain the area to be repaired. After the repair coating is applied to the area to be repaired, the repair of the area to be repaired is achieved. Among them, the defocus amount of the laser is ±2mm. Since the substrate will have a certain degree of deformation during the production and use process, resulting in its surface not being completely flat, controlling the defocus amount of the laser to ±2mm can ensure that the laser can effectively act on the coating on the surface of the substrate, achieve the purpose of coating treatment, and the energy of the laser will not be excessively dispersed, thereby improving the removal efficiency of the coating, reducing the difficulty of removing the coating from the surface of the substrate, and simplifying the repair process. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0041] Figure 1 It is a schematic flow chart of a coating repair method provided in an embodiment of the present application;

[0042] Figure 2 is a schematic diagram of the process of laser modification treatment provided in an embodiment of the present application;

[0043] Figure 3 It is a schematic diagram of the process of laser vaporization treatment provided in an embodiment of the present application.

[0044] Description of reference numerals:

[0045] 1. Substrate; 2. Coating. DETAILED DESCRIPTION

[0046] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present application. In addition, it should be understood that the specific implementation methods described herein are only used to illustrate and explain the present application, and are not used to limit the present application.

[0047] In a first aspect, an embodiment of the present application provides a method for repairing a coating, such as Figure 1 As shown, including:

[0048] The coating corresponding to at least the defective area is processed by laser to obtain the area to be repaired; wherein the defocus amount of the laser is ±2 mm;

[0049] A repair coating is applied to the area to be repaired, and the area to be repaired is repaired.

[0050] In the method for repairing the substrate coating provided in the embodiment of the present application, a laser is used to process at least the coating corresponding to the defective area to obtain the area to be repaired. After the repair coating is applied to the area to be repaired, the repair of the area to be repaired is achieved. Among them, the defocus amount of the laser is ±2mm. Since the substrate will be deformed to a certain extent during the production and use process, resulting in its surface not being completely flat, controlling the defocus amount of the laser to ±2mm can ensure that the laser can act on the coating on the surface of the substrate, achieve the purpose of coating treatment, and the energy of the laser will not be excessively dispersed, thereby improving the removal efficiency of the coating, reducing the difficulty of removing the coating from the substrate surface, and simplifying the repair process.

[0051] Among them, the defocus of the laser refers to the distance between the laser focus and the substance being acted on. By setting the defocus of the laser to ±2mm, the energy distribution can be relatively uniform when the laser is used to treat the coating, avoiding problems such as severe ablation due to excessive concentration of laser energy, and reducing damage to the substrate. Since the surface of the substrate is not completely flat, by setting a suitable defocus, a larger action area can be formed, thereby improving the efficiency of removing the coating. In addition, the defocus of the laser is ±2mm, which will not cause the energy of the laser to be too dispersed, thereby ensuring the stability of the effect and removal efficiency of removing the coating.

[0052] Exemplarily, the coating may be an insulating coating, which can improve the insulation performance of the covered object and provide protection and waterproofing for the covered object.

[0053] In some embodiments, during the process of laser treatment of the coating, the temperature rise on the surface of the substrate is ≤60°C. By controlling the temperature rise on the surface of the substrate to below 60°C, the thermal stress on the substrate caused by high temperature can be reduced, and deformation, cracking and other damage to the substrate due to excessive thermal stress can be avoided. It also helps to maintain the original performance of the substrate, and it can still meet the use requirements after removing the coating on its surface. If the temperature rise on the surface of the substrate is too high, it is easy to cause the heat-affected area to be too large, thereby reducing the accuracy and quality of laser treatment to remove the coating. Excessive temperature rise can also cause oxidation, discoloration and other phenomena on the surface of the substrate. When the substrate is a battery cell casing, if the temperature rise on the surface of the substrate is too high, it is also easy to cause thermal runaway of the battery cell, which poses a safety risk.

[0054] The temperature rise of the substrate surface refers to the increase in the substrate surface temperature relative to the ambient temperature during the laser treatment process. The temperature rise of the substrate surface can be controlled by controlling the laser power, scanning speed and other parameters.

[0055] In some embodiments, laser is used to process at least the coating corresponding to the defective area, including:

[0056] Under a protective atmosphere, at least the coating corresponding to the defective area is processed by laser.

[0057] The protective atmosphere refers to placing the substrate and the coating in an atmosphere of inert gas to isolate the substrate and the coating from contact with the air.

[0058] The high temperature and high energy generated by the laser during laser processing can easily cause thermal damage to the substrate, such as deformation or burns, and adding a protective gas can effectively reduce this risk. In addition, during laser processing, if the coating comes into contact with oxygen in the air, it is easy to burn, posing a safety risk. Laser processing under a protective atmosphere can reduce or avoid coating combustion and improve safety.

[0059] The protective atmosphere includes an inert gas atmosphere such as a nitrogen atmosphere or an argon atmosphere. Preferably, the nitrogen atmosphere can effectively isolate oxygen, prevent the substrate from oxidizing with oxygen in the air, reduce or avoid coating combustion, and has a low cost.

[0060] In some embodiments, before using laser to process at least the coating corresponding to the defective area, the method further includes:

[0061] Identify defective areas on the substrate surface and obtain identification results.

[0062] According to different recognition results, different laser processing methods can be used to remove the coating on the surface of the substrate. One embodiment is to remove all coatings on the surface of the substrate by laser modification, and then repair the surface of the substrate as a whole; another embodiment is to remove the coating corresponding to the defective area by laser vaporization, and perform targeted repairs on the repairable area where the coating is removed; another embodiment is to remove all coatings on the surface of the substrate by laser vaporization, and then repair the surface of the substrate as a whole. The details are as follows:

[0063] Example 1

[0064] In this embodiment, laser is used to process at least the coating corresponding to the defective area, including:

[0065] Applying laser to the contact surface between the substrate and the coating so that the substrate is separated from at least the coating corresponding to the defective area;

[0066] The coating is peeled off from the substrate surface.

[0067] That is, this embodiment uses laser modification processing to modify the coating at the contact surface between the substrate and the coating, so that the substrate and the coating are separated from each other, and then the two are peeled off to achieve the purpose of removing the coating from the surface of the substrate.

[0068] Specifically, during the laser modification process, the laser is applied to the contact surface between the substrate and the coating. Under the action of the high temperature and high energy generated by the laser, the coating near the contact surface is carbonized into particles, so that the coating and the substrate are no longer bonded and separated. After the coating and the substrate are separated, since the coating and the substrate are no longer bonded, it is easy to peel the coating off the substrate surface and remove the coating on the substrate surface, which is convenient for subsequent repair of the substrate surface.

[0069] It can be understood that, in this embodiment, only the coating corresponding to the defective area may be processed, or part or all of the coating on the surface of the substrate may be removed, as long as the coating corresponding to the defective area can be covered.

[0070] In some embodiments, the power of the laser is less than 500 W. When the power of the laser is too high, the coating will be vaporized and defects will be easily generated on the surface of the substrate, affecting the subsequent repair effect.

[0071] Illustratively, the power of the laser can be set to 50W, 100W, 150W, 200W, 250W, 300W, 350W, 400W, 450W or 500W.

[0072] In some embodiments, after stripping the coating from the surface of the substrate, the method further comprises:

[0073] The substrate surface is cleaned to remove carbides on the substrate surface.

[0074] During the laser modification process, the coating will be carbonized. After the coating is separated from the substrate surface, a small amount of carbonized layer will adhere to the substrate surface, affecting the adhesion between the repair coating and the substrate during the subsequent repair process. In order to improve the adhesion between the repair coating and the substrate during the repair process, the substrate surface is cleaned to ensure the subsequent repair effect.

[0075] The substrate surface can be cleaned by laser cleaning or water washing, and laser cleaning is preferred, as it has higher cleaning efficiency and better cleaning effect, and makes the substrate surface have better morphology.

[0076] When the laser treatment method of this embodiment is adopted, the number of treatments is ≤3 times. After the laser modification treatment, the surface of the substrate will be damaged to a certain extent, resulting in an increase in the irregularity of the surface morphology of the substrate, and the more times the laser modification treatment is performed, the higher the irregularity of the surface morphology of the substrate. When the number of laser modification treatments is greater than 3 times, the irregularity of the surface morphology of the substrate is high. When the laser acts on the contact surface between the substrate and the coating again, the energy of the laser will be irregularly dissipated, making it difficult to completely separate the coating from the substrate. Therefore, when laser modification treatment is adopted, the number of times is controlled to be less than 3 times.

[0077] like Figure 2 , the laser acts on the contact surface between the substrate 1 and the coating 2 (the arrow indicates the laser), so that the laser energy is concentrated on the contact surface; under the action of the laser, the coating 2 at the contact surface is carbonized to form a carbonized layer, thereby separating the substrate 1 and the coating 2, making it easier to peel off and remove the coating 2 from the substrate 1. The substrate 1 after removing the coating 2 can be repaired later.

[0078] Example 2

[0079] In this embodiment, laser is used to process at least the coating corresponding to the defective area, including:

[0080] The laser is used to act on at least the coating corresponding to the defective area to at least vaporize the coating corresponding to the defective area, so as to at least remove the coating corresponding to the defective area from the surface of the substrate.

[0081] That is, the coating on the surface of the substrate is treated by laser vaporization, so that the coating in the corresponding area is directly vaporized, thereby achieving the purpose of removing the coating from the surface of the substrate.

[0082] During the laser vaporization process, the laser directly acts on the coating corresponding to the defective area, causing the coating there to be directly vaporized, while the coating in other areas not affected by the laser remains attached to the surface of the substrate. At least the coating corresponding to the defective area is removed, forming an area to be repaired, and then the area to be repaired can be repaired later.

[0083] It can be understood that, in this embodiment, only the coating corresponding to the defective area may be processed, or part or all of the coating on the surface of the substrate may be removed, as long as the coating corresponding to the defective area can be covered.

[0084] In some embodiments, the power of the laser is 500-1500W. During the laser vaporization process, the laser needs to act directly on the coating corresponding to the defective area. The high-energy laser can directly vaporize the coating in the corresponding area, thereby achieving the purpose of removing the coating. Therefore, in order to ensure that the coating can be vaporized, a higher-power laser is used in the laser vaporization process. However, if the power of the laser is too high, it is easy to cause severe ablation of the substrate surface, causing defects on the substrate surface, affecting the adhesion between the repair coating and the substrate in the subsequent repair process. In order to ensure that the coating can be effectively vaporized and reduce the impact of the laser on the substrate surface, the power of the laser is controlled at 500W-1500W.

[0085] Illustratively, the power of the laser can be set to 500W, 600W, 700W, 800W, 900W, 1000W, 1100W, 1200W, 1300W, 1400W or 1500W.

[0086] In some embodiments, repairing the area to be repaired includes:

[0087] Identify the location of the area to be repaired and apply a repair coating to the area to be repaired;

[0088] The repair coating has the same thickness as the coating.

[0089] Exemplarily, a CCD (Charge-Coupled Device) is used to identify the edge position of the area to be repaired on the surface of the substrate, and a printing directory of the area to be repaired is drawn. Then, the printing device prints on the surface of the substrate according to the printing directory, so that the area to be repaired is re-covered with a layer of repair coating. In order to ensure that the repaired area to be repaired is consistent with other areas, the thickness of the repair coating is the same as that of the coating. For example, if the thickness of the coating on the substrate surface is 90μm-110μm, the thickness of the repair coating is also 90μm-110μm.

[0090] In some embodiments, repairing the area to be repaired includes:

[0091] Identify the area to be repaired, and apply a repair coating on the area to be repaired and on the circumference of the edge of the area to be repaired, so that the repair coating is formed on the area to be repaired, and a coating overlapping area is formed on the circumference of the edge of the area to be repaired;

[0092] The thickness of the coating is T1, the thickness of the overlapping area of ​​the coating is T2, and 0.5T1≤T2≤2T1.

[0093] When repairing the area to be repaired, coating, spraying, etc. can be used. In order to make the repair coating better cover the area to be repaired, a coating overlapping area can be formed in the circumferential direction of the edge of the area to be repaired. By controlling the thickness of the coating overlapping area and the thickness of the original coating within the above range, a better repair effect can be achieved while ensuring a certain thickness uniformity.

[0094] like Figure 3 As shown, the laser directly acts on the coating 2 corresponding to the defective area, so that the coating 2 there is directly vaporized to form the area to be repaired, while the remaining area is not vaporized by the laser and remains on the surface of the substrate 1. Targeted repair can be performed on the area to be repaired later.

[0095] Example 3

[0096] In this embodiment, laser is used to process at least the coating corresponding to the defective area, including:

[0097] Laser is used to act on all coatings on the surface of the substrate, so that all coatings on the surface of the substrate are vaporized and all coatings on the surface of the substrate are removed from the surface of the substrate.

[0098] That is, all coatings on the surface of the substrate are treated by laser vaporization, so that all coatings on the surface of the substrate are vaporized, thereby achieving the purpose of removing all coatings from the surface of the substrate.

[0099] During the laser vaporization process, the laser directly acts on the coating on the surface of the substrate, vaporizing all the coating on the surface of the substrate, thereby achieving the purpose of removing all the coating on the surface of the substrate. Subsequently, the substrate surface after the coating is removed can be repaired as a whole.

[0100] In some embodiments, the power of the laser is 500-1500W. In order to ensure that the coating can be vaporized, a higher power laser is used in the laser vaporization process. However, if the power of the laser is too high, it is easy to cause serious ablation of the substrate surface, causing defects on the substrate surface, affecting the adhesion between the repair coating and the substrate in the subsequent repair process. In order to ensure that the coating can be effectively vaporized and reduce the impact of the laser on the substrate surface, the power of the laser is controlled at 500W-1500W.

[0101] Illustratively, the power of the laser can be set to 500W, 600W, 700W, 800W, 900W, 1000W, 1100W, 1200W, 1300W, 1400W or 1500W.

[0102] It is understandable that in the process of repairing the coating, the appropriate repair method can be selected according to the type of defective area, the area of ​​the defective area or the expected repair effect. Laser vaporization can directly vaporize the coating on the surface of the substrate with high efficiency, but the energy of the laser is high and will have a certain impact on the substrate. Laser modification can separate the substrate and the coating with less damage to the substrate, but the efficiency is low and all the coatings on the surface of the substrate need to be removed.

[0103] In some embodiments, the defective area includes at least one of a damaged area, an uneven thickness area, a bulging area, a bubble area, a peeling area, and a deformed area.

[0104] Defective areas refer to areas that are defective or do not meet the expected quality standards. When there are damaged areas, uneven thickness areas, bulging areas, blistering areas, peeling areas or deformation areas in the coating, the quality of the coating will be affected.

[0105] In some embodiments, when the defective area includes a damaged area or a peeling area, a laser is applied to at least the coating corresponding to the defective area to vaporize at least the coating corresponding to the defective area, so as to remove at least the coating corresponding to the defective area from the surface of the substrate;

[0106] When the defective area includes at least one of an uneven thickness area, a bulging area, a blistering area and a deformed area, a laser is applied to the contact surface between the substrate and the coating to separate the substrate from at least the coating corresponding to the defective area.

[0107] When the defective area includes a damaged area or a peeling area, the coating is easy to pass through the damaged area or the peeling area and contact with the outside air during the laser treatment, resulting in combustion. It is preferred to use a gasification mode for treatment to remove the coating corresponding to the defective area or all the coatings on the substrate surface. In order to improve safety, it can be carried out in a protective atmosphere to directly gasify the coating and improve the removal efficiency.

[0108] When the defective area includes at least one of the uneven thickness area, bulging area, blister area and deformation area, and the coating is not damaged, the laser modification treatment can be performed by acting the laser on the contact surface between the substrate and the coating. Since the laser action position does not come into contact with the outside air during the laser modification treatment, the risk of combustion caused by the contact between the coating and the air is avoided, and the safety performance is guaranteed.

[0109] In some embodiments, before using laser to treat at least the coating corresponding to the defective area on the surface of the substrate, the method further includes:

[0110] Obtain the area of ​​the defective area and the total area of ​​all coatings on the substrate surface;

[0111] According to the area of ​​the defective area and the total area of ​​all coatings on the surface of the substrate, a ratio of the area of ​​the defective area to the total area of ​​all coatings on the surface of the substrate is obtained;

[0112] When the ratio is less than or equal to 30%, laser treatment is used to remove the coating corresponding to the defective area;

[0113] When the ratio is greater than 30%, the entire coating on the substrate surface is removed by laser treatment.

[0114] That is, the laser treatment process is selected according to the ratio of the area of ​​the defective area to the total area of ​​all coatings on the substrate surface. When the ratio is less than or equal to 30%, since the area of ​​the coating that needs to be repaired is relatively small, laser treatment can be used to specifically remove the coating corresponding to the defective area, and retain the remaining coating, which can improve the treatment efficiency, reduce the repair area, and reduce the repair cost. When the ratio is greater than 30%, since the area of ​​the coating that needs to be repaired is large, all coatings on the surface of the substrate can be removed by laser treatment, thereby achieving a better repair effect. When removing all coatings on the surface of the substrate, laser modification treatment can be used to make the laser act on the contact surface between the coating and the substrate, and then the coating can be trimmed and peeled off, or laser vaporization treatment can be used to make the laser act directly on the coating, so that all coatings on the surface of the substrate are vaporized, and then the substrate after the coating is removed is repaired as a whole.

[0115] It is understandable that the present embodiment uses 30% of the ratio of the area of ​​the defective region to the total area of ​​all coatings on the substrate surface as a basis for judgment, but it can also be adjusted according to specific process requirements during actual application.

[0116] In a second aspect, an embodiment of the present application provides a battery cell shell, which is repaired using the above coating repair method.

[0117] The cell shell includes a cell shell and a coating disposed on the surface of the cell shell. The coating on the surface of the cell shell may be an insulating coating.

[0118] The coating on the surface of the battery cell shell can improve the insulation performance of the battery cell shell, resist moisture, pollution and chemical corrosion to the battery cell shell, improve the stability of the battery cell, enhance the safety of the battery cell and prevent thermal runaway. During the production and use of the battery cell, defects may occur in the coating on the surface of the battery cell shell. The coating is tightly combined with the battery cell shell. The above-mentioned coating repair method can improve the removal efficiency of the coating, reduce the difficulty of removing the coating from the surface of the battery cell shell, simplify the repair process, and thus save costs.

[0119] In a third aspect, an embodiment of the present application provides a battery cell, comprising the battery cell shell as described above. The battery cell provided by the embodiment of the present application has all the beneficial effects of the battery cell shell as described above, which will not be described in detail here.

[0120] The embodiments of the present application are introduced in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A coating repair method, characterized in that: include: The coating corresponding to at least the defective area on the surface of the substrate is processed by laser to obtain the area to be repaired; wherein the defocus amount of the laser is ±2 mm; A repair coating is applied to the area to be repaired, and the area to be repaired is repaired.

2. The coating repair method according to claim 1, characterized in that: During the process of treating the coating with the laser, the temperature rise on the surface of the substrate is ≤60°C.

3. The coating repair method according to claim 1, characterized in that: The method of using laser to process at least the coating corresponding to the defective area on the surface of the substrate comprises: Under a protective atmosphere, laser is used to process at least the coating corresponding to the defective area on the surface of the substrate.

4. The method for repairing a coating according to any one of claims 1 to 3, characterized in that: The method of using laser to process at least the coating corresponding to the defective area includes: Applying the laser to the contact surface between the substrate and the coating so that the substrate is at least separated from the coating corresponding to the defective area; The coating is peeled off from the substrate surface.

5. The coating repair method according to claim 4, characterized in that: The power of the laser is below 500W.

6. The coating repair method according to claim 5, characterized in that: After the coating is peeled off from the surface of the substrate, the method further comprises: The surface of the substrate is cleaned to remove carbides on the surface of the substrate.

7. The coating repair method according to claim 6, characterized in that: The step of applying the laser to the contact surface between the substrate and the coating so that the substrate is separated from at least the coating corresponding to the defective area comprises: The laser is applied to the contact surface between the substrate and the coating, so that the substrate and all the coatings on the surface of the substrate are separated from each other.

8. The coating repair method according to any one of claims 1 to 3, characterized in that: The method of using laser to process at least the coating corresponding to the defective area on the surface of the substrate comprises: The laser is applied to at least the coating layer corresponding to the defective area to vaporize at least the coating layer corresponding to the defective area, so as to remove at least the coating layer corresponding to the defective area from the surface of the substrate.

9. The coating repair method according to claim 8, characterized in that: The power of the laser is 500-1500W.

10. The coating repair method according to claim 9, characterized in that: The repairing of the area to be repaired includes: Identifying the area to be repaired, and applying the repair coating to the area to be repaired; Wherein, the repair coating has the same thickness as the coating.

11. The coating repair method according to claim 10, characterized in that: The repairing of the area to be repaired includes: Identify the area to be repaired, and apply the repair coating on the area to be repaired and on the circumference of the edge of the area to be repaired, so that the repair coating is formed on the area to be repaired and a coating overlapping area is formed on the circumference of the edge of the area to be repaired; Wherein, the thickness of the coating is T1, the thickness of the overlapping area of ​​the coating is T2, and 0.5T1≤T2≤2T1.

12. The coating repair method according to any one of claims 1 to 3, characterized in that: The defective area includes at least one of a damaged area, an uneven thickness area, a bulging area, a blistering area, a peeling area and a deformed area.

13. The coating repair method according to claim 12, characterized in that: When the defective area includes a damaged area or a peeling area, the laser is applied to at least the coating corresponding to the defective area to vaporize at least the coating corresponding to the defective area, so as to remove at least the coating corresponding to the defective area from the surface of the substrate; When the defective area includes at least one of an uneven thickness area, a bulging area, a blistering area and a deformed area, the laser is applied to the contact surface between the substrate and the coating to separate the substrate from at least the coating corresponding to the defective area.

14. The coating repair method according to any one of claims 1 to 3, characterized in that: Before the laser is used to treat at least the coating corresponding to the defective area on the surface of the substrate, the method further comprises: Obtaining the area of ​​the defective region and the total area of ​​all the coatings on the surface of the substrate; According to the area of ​​the defective area and the total area of ​​all the coatings on the surface of the substrate, obtaining a ratio of the area of ​​the defective area to the total area of ​​all the coatings on the surface of the substrate; When the ratio is less than or equal to 30%, the laser is used to remove the coating corresponding to the defective area; When the ratio is greater than 30%, the laser is used to remove all of the coating on the surface of the substrate.

15. A battery cell casing, characterized in that: The battery cell shell is repaired by using the coating repair method according to any one of claims 1 to 14.

16. A battery cell, characterized in that: Comprising the battery cell casing as claimed in claim 15.

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