Battery cell manufacturing method, end cap assembly, battery cell and battery device

Abstract

The invention discloses a manufacturing method of a battery monomer, an end cover assembly, the battery monomer and a battery device, the manufacturing method of the battery monomer comprises the following steps: determining a target film according to the current type of an electrolyte of the battery monomer, when the current type of electrolyte is arranged on the target film, the target film is not corroded, and when the current type of electrolyte is arranged on the target film, the target film is not corroded; and determining processing parameters according to the structural parameters of the code carving area of the battery monomer, processing the target film into a protective film according to the processing parameters, and bonding the protective film to the outer surface of the battery monomer so as to enable the code carving area to be covered by the protective film. When the electrolyte splashes, the protective film shields the code carving area, and the electrolyte cannot fall on the code carving area, so that the condition that the code carving area is corroded by the electrolyte is effectively reduced, the code carving area can be effectively identified, and the qualified rate of the single battery is effectively improved.

Description

Technical Field

[0001] The present application relates to the technical field of battery manufacturing, and in particular to a manufacturing method of a battery cell, an end cover assembly, a battery cell and a battery device. Background Art

[0002] With the development of new energy, more and more fields are using new energy as a power source. Due to its advantages such as high energy density, rechargeable, safe and environmentally friendly, battery devices are widely used in new energy vehicles, consumer electronics, energy storage systems and other fields.

[0003] In the related art, the battery device includes a battery cell, and a coding area is provided on the battery cell. During the manufacturing process of the battery cell, the coding area is easily corroded by the electrolyte, thereby causing the coding area to be unrecognizable. Summary of the invention

[0004] In view of the above problems, the present application provides a method for manufacturing a battery cell, an end cover assembly, a battery cell and a battery device, which solve the problem of electrolyte corrosion in the coding area.

[0005] The first aspect of the present application provides a method for manufacturing a battery cell, the method comprising: Determining a target film according to a current type of electrolyte of the battery cell, wherein the target film is not corroded when the current type of electrolyte is disposed on the target film; Determine the processing parameters according to the structural parameters of the coding area of ​​the battery cell; According to processing parameters, the target film is processed into a protective film; The protective film is adhered to the outer surface of the battery cell so that the engraved code area is covered by the protective film.

[0006] Specifically, according to the current type of electrolyte of the processed battery cell, a target film that is compatible with the electrolyte is selected, that is, the target film cannot be corroded by the electrolyte, and the target film is processed into the protective film required by the battery cell, and then the processed protective film is pasted to the outer surface of the battery cell and covers the engraved area to isolate the engraved area from the outside world. When the electrolyte splashes, the protective film blocks the engraved area, and the electrolyte cannot fall on the engraved area, thereby effectively reducing the occurrence of electrolyte corrosion of the engraved area, so that the engraved area can be effectively identified, thereby effectively meeting the requirement of improving the qualified rate of the battery cell.

[0007] In some embodiments of the present application, determining a target membrane according to a current type of an electrolyte of a battery cell includes: Get the current type of electrolyte of the battery cell; According to the current type of electrolyte, preparing a plurality of sample films, wherein at least a plurality of sample films are made of different materials; The plurality of sample films are tested, and the target film is determined from the plurality of sample films according to the test data.

[0008] Specifically, according to the current type of electrolyte of the battery cell, multiple sample films with different materials are prepared, and the multiple sample films are tested. The target film is determined based on the test data. Such a setting can make the target film effectively adapt to the battery cell, thereby reducing the corrosion of the engraved area after the electrolyte corrodes the protective film.

[0009] In some embodiments of the present application, testing the plurality of sample films, and determining the target film from the plurality of sample films according to the test data, comprises: Conduct corrosion tests on multiple sample films using the current type of electrolyte; According to the fact that the sample film is not corroded by the current type of electrolyte, a sample film that is preliminarily qualified is determined from among the multiple sample films; The preliminarily qualified sample films are reviewed and the design requirements are met according to the review parameters, and a target film is determined from the preliminarily qualified sample films, wherein the design requirements include at least one of transmittance, thickness, temperature resistance, release force and insulation.

[0010] Specifically, in the process of testing multiple sample membranes, the corrosion test can be used to directly screen out sample membranes that can resist the electrolyte of the battery cell, and then the screened sample membranes are reviewed, and the sample membranes that pass the review are determined as target membranes. Such a setting can effectively improve the quality of the protective film, so that the protective film can meet the current usage requirements of the battery cell.

[0011] In some embodiments of the present application, the step of reviewing the preliminarily qualified sample films and determining the target film from the preliminarily qualified sample films according to the review parameters to determine whether the target film meets the design requirements includes: Testing the transmittance of the initially qualified sample film, and determining the sample film with qualified transmittance according to the transmittance of the sample film being greater than or equal to a first threshold; Testing the thickness of the initially qualified sample film, and determining the sample film with qualified thickness according to the thickness of the sample film being less than or equal to a second threshold; Testing the temperature resistance of the preliminarily qualified sample films, and determining the sample films with qualified temperature resistance according to the tolerance temperature of the sample films being greater than or equal to a third threshold; Testing the release force of the initially qualified sample film, and determining the sample film with qualified release force according to the release force of the sample film being greater than or equal to a fourth threshold; The insulation of the preliminarily qualified sample film is tested, and the sample film with qualified resistance is determined according to the resistance value of the sample film being greater than or equal to the fifth threshold.

[0012] Specifically, when reviewing the preliminarily qualified sample films, the preliminarily qualified sample films are tested respectively in terms of transmittance, thickness, temperature resistance, release force and insulation, so that the transmittance, thickness, temperature resistance, release force and insulation of the determined target film meet the use requirements of the battery cell, so that the protective film can be effectively adapted to the battery cell.

[0013] In some embodiments of the present application, the first threshold is greater than or equal to 50% and less than or equal to 100%. Such a setting can make the protective film have good light transmittance, reduce the shielding of the coding area of ​​the battery cell, so as to achieve effective identification of the coding area, thereby meeting the production needs.

[0014] In some embodiments of the present application, the second threshold is greater than 0 micrometers and less than or equal to 150 micrometers. Such a setting can effectively control the thickness of the protective film while being able to resist electrolyte corrosion, thereby reducing the space occupied by the protective film and the manufacturing cost of the protective film.

[0015] In some embodiments of the present application, the third threshold is greater than or equal to 300 degrees Celsius and less than or equal to 400 degrees Celsius. This configuration enables the protective film to have the ability to withstand high temperatures, thereby reducing the adverse effects of welding heat on the protective film during welding of battery cells.

[0016] In some embodiments of the present application, the fourth threshold is greater than or equal to 1 Newton / 25 millimeters and less than or equal to 10 Newtons / 25 millimeters. This arrangement enables the protective film to have good structural strength after being pasted, thereby reducing the risk of the protective film falling off.

[0017] In some embodiments of the present application, the fifth threshold is greater than 10 to the fifth power ohms and less than or equal to 10 to the tenth power ohms. This configuration enables the protective film to have good insulation properties and reduces the situation where the protective film conducts electricity and causes short circuits in other components.

[0018] In some embodiments of the present application, processing parameters are determined based on the structural parameters of the coding area of ​​the battery cell, the structural parameters include the shape of the coding area and the size of the coding area, and the processing parameters include the shape of the protective film and the size of the protective film, wherein the shape of the protective film is consistent with the shape of the coding area, and the size of the protective film is greater than or equal to the size of the coding area.

[0019] Such an arrangement enables the protective film to be effectively adapted to the code engraving area. On the basis of effectively protecting the code engraving area, the amount of protective film used can be reduced, so that the manufacturing cost of the battery cell can be reduced. In some embodiments of the present application, when the protective film is attached to the outer surface of the battery cell, the entire coding area is covered by the protective film, and the minimum distance between the edge of the coding area and the edge of the protective film is greater than or equal to 0 mm and less than or equal to 2 mm.

[0020] Such an arrangement enables the protective film to be effectively matched with the code engraving area. On the basis of effectively protecting the code engraving area, the amount of the protective film can be reduced, so that the manufacturing cost of the battery cell can be reduced.

[0021] In some embodiments of the present application, the target film is processed into a protective film according to processing parameters, and the method of processing the target film into the protective film is cutting.

[0022] Such an arrangement makes it easier to process the target film, can effectively improve the processing efficiency, and speed up the production rhythm.

[0023] In some embodiments of the present application, the protective film is bonded to the outer surface of the battery cell so that the code area is covered by the protective film, including: Receive and secure battery cells; Acquire the current state of the outer surface of the battery cell having the coding area; According to the fact that no electrolyte remains on the outer surface of the battery cell having the code engraving area, the protective film is controlled to be attached to the outer surface of the battery cell so that the entire code engraving area is covered by the protective film.

[0024] Specifically, when sticking the protective film to the battery cell, the battery cell is first fixed, and then the surface of the battery cell with the engraved area is tested to see if there is any residual electrolyte. After confirming that there is no residual electrolyte, the protective film is stuck to the battery cell, thereby reducing the situation where there is residual electrolyte between the protective film and the battery cell.

[0025] In some embodiments of the present application, according to the fact that no electrolyte remains on the outer surface of the battery cell having the code area, controlling the protective film to be attached to the outer surface of the battery cell so that the entire code area is covered by the protective film includes: Get the current position of the engraving area; The control protection film is arranged above the code engraving area; Controlling the protective film to rotate about a preset rotation axis to adjust the angle of the protective film, wherein the preset rotation axis is perpendicular to the plane where the engraved area is located; Controlling the translation of the protective film so that the projection of the protective film on the battery cell can cover the entire coding area, wherein the translation direction of the protective film is parallel to the coding area; The control protection film is adhered to the outer surface of the battery cell to cover the entire coding area.

[0026] Specifically, by controlling the angle and position of the protective film, the adhesion accuracy of the protective film can be effectively improved, so that the protective film can effectively protect the engraved area, further reducing the corrosion problem of the engraved area caused by the electrolyte.

[0027] In some embodiments of the present application, the control protection film is attached to the outer surface of the battery cell to cover the entire coding area, including: The control protection film is attached to the outer surface of the battery cell; Apply a preset pressure on the side of the protective film facing away from the battery cell; When the pressure application time of the protective film reaches a preset time, the preset pressure on the protective film is released.

[0028] Specifically, during the process of sticking the protective film, by setting a preset pressure and a preset time, the protective film can be pasted under the action of the sticking pressure, thereby improving the sticking strength of the protective film and further reducing the possibility of the protective film falling off.

[0029] In some embodiments of the present application, the pressure exerted on the protective film by the preset pressure is in the range of 0.4 MPa to 0.6 MPa.

[0030] Specifically, during the pasting process of the protective film, by setting the pressure exerted on the protective film by the preset pressure within the range of 0.4 MPa to 0.6 MPa, the protective film can have sufficient pasting strength during the pasting process while reducing the possibility of squeezing and deformation of the battery cell.

[0031] In some embodiments of the present application, the preset time is in the range of 5 seconds to 25 seconds. Specifically, by setting the preset time in the range of 5 seconds to 25 seconds, the protective film and the battery cell can have good adhesion strength during the adhesion process of the protective film, thereby further improving the adhesion effect of the battery cell.

[0032] A second aspect of the present application provides an end cap assembly, the end cap assembly comprising: An end cover, the outer surface of which is provided with a code engraving area; The protective film is the protective film as described above, and the protective film is pasted on the outer surface of the end cover and covers the engraved area.

[0033] Specifically, during the processing of the battery cell, according to the current type of electrolyte of the processed battery cell, a target film that is compatible with the electrolyte is selected, that is, the target film cannot be corroded by the electrolyte, and the target film is processed into the protective film required by the battery cell, and then the processed protective film is pasted to the outer surface of the battery cell and covers the engraved area to isolate the engraved area from the outside world. When the electrolyte splashes, the protective film blocks the engraved area, and the electrolyte cannot fall on the engraved area, thereby effectively reducing the occurrence of electrolyte corrosion of the engraved area, so that the engraved area can be effectively identified, thereby effectively meeting the requirement of improving the qualified rate of the battery cell.

[0034] A third aspect of the present application provides a battery cell, which is manufactured by the above battery production line.

[0035] Specifically, when processing the battery cell, according to the current type of electrolyte of the processed battery cell, a target film that is compatible with the electrolyte is selected, that is, the target film cannot be corroded by the electrolyte, and the target film is processed into the protective film required by the battery cell, and then the processed protective film is pasted to the outer surface of the battery cell and covers the engraved area to isolate the engraved area from the outside world. When the electrolyte splashes, the protective film blocks the engraved area, and the electrolyte cannot fall on the engraved area, thereby effectively reducing the occurrence of electrolyte corrosion of the engraved area, so that the engraved area can be effectively identified, thereby effectively meeting the requirement of improving the qualified rate of the battery cell.

[0036] A fourth aspect of the present application provides a battery device, which includes the battery cell as described above.

[0037] Specifically, when processing the battery cell, according to the current type of electrolyte of the processed battery cell, a target film that is compatible with the electrolyte is selected, that is, the target film cannot be corroded by the electrolyte, and the target film is processed into the protective film required by the battery cell, and then the processed protective film is pasted to the outer surface of the battery cell and covers the engraved area to isolate the engraved area from the outside world. When the electrolyte splashes, the protective film blocks the engraved area, and the electrolyte cannot fall on the engraved area, thereby effectively reducing the occurrence of electrolyte corrosion of the engraved area, so that the engraved area can be effectively identified, thereby effectively meeting the requirement of improving the qualified rate of the battery cell.

[0038] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1Schematically shows a structural diagram of a battery device according to an embodiment of the present application; Figure 2 A partial structural diagram of a battery device according to an embodiment of the present application is schematically shown; Figure 3 A partial structural diagram of a battery device according to an embodiment of the present application is schematically shown; Figure 4 The flowchart of a method for manufacturing a battery cell according to one embodiment of the present application is schematically shown.

[0040] The reference numerals are as follows: 100. Battery device; 110. Battery monomer assembly; 10. Battery cells; 11. Shell; 111. End cover; 112. Shell; 12. Electrode terminal; 13. Liquid injection hole; 14. Pressure relief mechanism; 15. Protective film; 16. Code engraving area; 120, box body; 121, first box; 122, second box; a. First distance; b. Second distance. DETAILED DESCRIPTION

[0041] The following embodiments of the technical solution of the present application will be described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0043] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0044] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0045] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0046] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0047] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0048] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0049] At present, from the perspective of market development, the application of battery devices is becoming more and more extensive. Battery devices are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, as well as military equipment and aerospace and other fields. With the continuous expansion of the application field of battery devices, the market demand is also constantly expanding.

[0050] In the related art, the battery device includes a battery cell, and a coding area is provided on the battery cell. During the manufacturing process of the battery cell, the coding area is easily corroded by the electrolyte, thereby causing the coding area to be unrecognizable.

[0051] In the present application, during the manufacturing process of the battery cell, the target film is determined according to the current type of the electrolyte of the battery cell, wherein when the target film is provided with the current type of electrolyte, the target film is not corroded, and the processing parameters are determined according to the structural parameters of the coding area of ​​the battery cell, and the target film is processed into a protective film according to the processing parameters, and the protective film is bonded to the outer surface of the battery cell so that the coding area is covered by the protective film. When the electrolyte splashes, the electrolyte cannot fall on the coding area because the protective film blocks the coding area, thereby effectively reducing the occurrence of electrolyte corrosion of the coding area, so that the coding area can be effectively identified, thereby effectively satisfying the improvement of the qualified rate of the battery cell.

[0052] The technical solutions described in the embodiments of the present application are not limited to the devices described above, but can also be applied to all devices using battery devices. However, for the sake of simplicity, the following embodiments are described using electric vehicles as examples.

[0053] For example, the vehicle may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A motor, a controller and a battery device may be arranged inside the vehicle, and the controller is used to control the battery device to power the motor. For example, a battery device may be arranged at the bottom, front or rear of the vehicle. The battery device may be used to power the vehicle, for example, the battery device may be used as an operating power source for the vehicle, for the circuit system of the vehicle, for example, for the working power requirements during the start-up, navigation and operation of the vehicle. In another embodiment of the present application, the battery device may not only be used as an operating power source for the vehicle, but also as a driving power source for the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0054] like Figure 1As shown, the battery apparatus 100 (Battery Apparatus) mentioned in the embodiment of the present application may include one or more battery cell assemblies 110 for providing voltage and capacity. The battery cell assembly 110 (Battery Cell Assembly) may include a plurality of battery cells 10, and the plurality of battery cells 10 are connected in series, in parallel or in mixed connection through a busbar component.

[0055] In some embodiments, a battery cell assembly 110 is generally formed by arranging a plurality of battery cells 10 .

[0056] As an example, the battery cell assembly 110 may be a battery module (Battery Module), and the battery module is formed by arranging and fixing a plurality of battery cells 10 to form an independent module. As an example, the battery module may be formed by bundling a plurality of battery cells 10 by a cable tie.

[0057] In some embodiments, Figure 2 As shown, the battery device 100 may be a battery pack, which includes a case 120 and one or more battery cell assemblies 110 , wherein the battery cell assemblies 110 are accommodated in the case 120 .

[0058] As an example, the battery cell assembly 110 may be a battery module, and the battery cell assembly 110 may be accommodated in the case 120 by fixing the battery module in the case 120 .

[0059] As an example, the battery cell assembly 110 may also be accommodated in the case 120 by directly fixing the plurality of battery cells 10 to the case 120 .

[0060] As an example, the box 120 may include a first box 121 and a second box 122. The first box 121 and the second box 122 are buckled together to form a closed space inside the box 120 to accommodate the battery cell assembly 110. The closed space here means covered or closed, which may be sealed or unsealed. The first box 121 may be a top cover or a bottom plate.

[0061] As an example, the box body 120 may include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are respectively connected to the frame, so that a closed space is formed inside the box body 120 to accommodate the battery cell assembly 110.

[0062] In some embodiments, the box 120 can be used as a part of the chassis structure of the vehicle. For example, part of the box 120 can become at least a part of the floor of the vehicle, or part of the box 120 can become at least a part of the cross beam and longitudinal beam of the vehicle.

[0063] The technical solutions described in the embodiments of the present application are applicable to various electrical devices using battery cells 10, such as mobile phones, portable devices, laptop computers, electric vehicles, electric toys, electric tools, vehicles, ships and spacecraft, for example, spacecraft include airplanes, rockets, space shuttles and spacecraft, etc.

[0064] In some embodiments of the present application, the battery cell 10 may be a secondary battery. A secondary battery refers to a battery cell 10 that can be continuously used by activating active materials by charging after the battery cell 10 is discharged.

[0065] The battery cell 10 can be a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel hydrogen battery, a nickel cadmium battery, a lead storage battery, etc., which is not limited in the embodiments of the present application.

[0066] In some embodiments of the present application, Figure 2 and Figure 3 As shown, the battery cell 10 includes a shell 11, a pressure relief mechanism, an electrode assembly and an insulating member. The shell includes a plurality of side walls, including a first side wall. The first side wall is provided with a pressure relief mechanism, and the pressure relief mechanism is configured to open or close according to whether the internal pressure of the shell reaches a pressure threshold. The electrode assembly is arranged inside the shell, and the insulating member is arranged inside the shell and between the shell and the electrode assembly for insulating and isolating the shell and the electrode assembly. The insulating member abuts against the electrode assembly.

[0067] As an example, the battery cell 10 can be a cylindrical battery cell, a prismatic battery cell, a soft-pack battery cell or a battery cell of other shapes. The prismatic battery cell includes a square shell battery cell, a blade-shaped battery cell, a polygonal battery, such as a hexagonal battery, etc. There is no special limitation in the present application.

[0068] The electrode assembly includes a positive electrode, a negative electrode, and a separator, and the separator is arranged between the negative electrode and the positive electrode. During the charge and discharge process of the battery cell 10, active ions (such as lithium ions) are inserted and removed back and forth between the positive electrode and the negative electrode. The separator is arranged between the positive electrode and the negative electrode, which can prevent the positive and negative electrodes from short-circuiting, and at the same time allow the active ions to pass through.

[0069] In some embodiments, the positive electrode may be a positive electrode sheet, and the positive electrode sheet may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0070] As an example, the positive electrode current collector has two surfaces facing each other in its thickness direction, and the positive electrode active material is disposed on either or both of the two facing surfaces of the positive electrode current collector.

[0071] As an example, the positive electrode current collector may be a metal foil, a conductive polymer material, a carbon material or a composite current collector. For example, as the metal foil, a pure metal, an alloy, a surface-treated metal, including but not limited to stainless steel, copper, aluminum, nickel, titanium or silver, etc., may be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0072] As an example, the positive electrode active material may include at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides, and their respective modified compounds. However, the present application is not limited to these materials, and other traditional materials that can be used as positive electrode active materials for batteries may also be used. These positive electrode active materials may be used alone or in combination of two or more. Among them, examples of lithium-containing phosphates may include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and a composite material of lithium iron manganese phosphate and carbon. Examples of lithium transition metal oxides may include, but are not limited to, lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also referred to as NCM 333 )、LiNi 0.5 Co 0.2 Mn 0.3 O2 (also referred to as NCM 523 )、LiNi 0.5 Co 0.25 Mn 0.25 O2 (also referred to as NCM 211 )、LiNi 0.6 Co 0.2 Mn 0.2 O2 (also referred to as NCM 622 )、LiNi 0.8 Co 0.1 Mn 0.1 O2 (also referred to as NCM 811 ), lithium nickel cobalt aluminum oxide (such as LiNi 0.8 Co 0.15 Al 0.05O2) and at least one of its modified compounds. The modified compound refers to a substance obtained by modifying the above substances by means of doping or coating.

[0073] In some embodiments, the positive electrode may be a foamed metal. The foamed metal may be a foamed nickel, a foamed copper, a foamed aluminum, a foamed alloy, or a foamed carbon. When the foamed metal is used as the positive electrode, the positive electrode active material may not be disposed on the surface of the foamed metal, but of course, the positive electrode active material may also be disposed. As an example, the positive electrode active material is filled or / and deposited in the foamed metal.

[0074] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0075] As an example, the negative electrode current collector may be a metal foil, a conductive polymer material, a carbon material or a composite current collector. For example, as the metal foil, a pure metal, an alloy, a surface-treated metal, including but not limited to stainless steel, copper, aluminum, nickel, titanium or silver, etc., may be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0076] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0077] As an example, the negative electrode current collector has two surfaces facing each other in its thickness direction, and the negative electrode active material is disposed on either or both of the two facing surfaces of the negative electrode current collector.

[0078] As an example, the negative electrode active material may adopt the negative electrode active material for the battery cell 10 known in the art. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, lithium titanate, etc. The silicon-based material may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The tin-based material may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, the present application is not limited to these materials, and other traditional materials that can be used as negative electrode active materials for the battery cell 10 may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0079] In some embodiments, the negative electrode may be a foam metal. The foam metal may be foam nickel, foam copper, foam aluminum, foam alloy, or foam carbon, etc. When the foam metal is used as the negative electrode sheet, the surface of the foam metal may not be provided with a negative electrode active material, but of course, a negative electrode active material may also be provided.

[0080] As an example, a negative electrode active material may be filled and / or deposited in the negative electrode current collector.

[0081] In some embodiments, the material of the positive electrode current collector may be aluminum, and the material of the negative electrode current collector may be copper.

[0082] In some embodiments, the electrode assembly further includes a separator disposed between the positive electrode and the negative electrode.

[0083] In some embodiments, the separator is a separator. The present application has no particular limitation on the type of separator, and any known separator with a porous structure having good chemical stability and mechanical stability can be selected.

[0084] As an example, the main material of the separator can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramic. The separator can be a single-layer film or a multi-layer composite film, without special restrictions. When the separator is a multi-layer composite film, the materials of each layer can be the same or different, without special restrictions. The separator can be a separate component located between the positive and negative electrodes, or it can be attached to the surface of the positive and negative electrodes. An inorganic particle coating, an organic particle coating, or an organic / inorganic composite coating can also be coated on the surface of the separator.

[0085] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive electrode and the negative electrode and serves to transmit ions and isolate the positive and negative electrodes.

[0086] The electrode assembly may be a wound structure, a laminated structure, or a mixed structure of a wound structure and a laminated structure.

[0087] In some embodiments, the electrode assembly is a wound structure, wherein the positive electrode sheet and the negative electrode sheet are wound into the wound structure.

[0088] In some embodiments, the electrode assembly is a laminate structure.

[0089] As an example, a plurality of positive electrode sheets and a plurality of negative electrode sheets may be provided respectively, and the plurality of positive electrode sheets and the plurality of negative electrode sheets may be alternately stacked.

[0090] As an example, a plurality of positive electrode sheets may be provided, and the negative electrode sheet may be folded to form a plurality of stacked folded segments, with a positive electrode sheet being sandwiched between adjacent folded segments.

[0091] As an example, both the positive electrode sheet and the negative electrode sheet are folded to form a plurality of folded sections that are stacked.

[0092] As an example, a plurality of separators may be provided, each of which is provided between any adjacent positive electrode sheets or negative electrode sheets.

[0093] As an example, the separator may be disposed continuously, and may be disposed between any adjacent positive electrode sheets or negative electrode sheets by folding or winding.

[0094] In some embodiments, the shape of the electrode assembly can be cylindrical, flat, or polygonal.

[0095] In some embodiments, the electrode sheet of the electrode assembly is provided with a tab, which can lead current out of the electrode assembly. The tab includes a positive tab and a negative tab.

[0096] In some embodiments, Figure 2 and Figure 3 As shown, a pressure relief mechanism 14 is provided on the housing 11 . The pressure relief mechanism 14 is used to discharge the internal gas of the battery cell 10 .

[0097] As an example, when the internal pressure or temperature of the battery cell 10 reaches a predetermined threshold, it is actuated to release the internal pressure or temperature. When the internal pressure or temperature of the battery cell 10 reaches a predetermined threshold, the pressure relief mechanism 14 performs an action or a weak structure provided in the pressure relief mechanism 14 is destroyed, thereby forming an opening or channel for the internal pressure or temperature to be released. The threshold design varies according to different design requirements. The threshold may depend on one or more materials of the positive electrode sheet, negative electrode sheet, electrolyte and separator in the battery cell 10.

[0098] As an example, the pressure relief mechanism 14 may be integrally formed with the housing 11 .

[0099] As an example, the pressure relief mechanism 14 may also be separately provided and connected to the housing 11 .

[0100] The "actuation" mentioned in this application means that the pressure relief mechanism is in action or activated to a certain state, so that the internal pressure and temperature of the battery cell 10 can be released. The action produced by the pressure relief mechanism 14 may include but is not limited to: the components in the pressure relief mechanism 14 move to form an exhaust channel, at least a part of the pressure relief mechanism 14 ruptures, breaks, is torn or opened, and so on. When the pressure relief mechanism 14 is actuated, the high-temperature and high-pressure substances inside the battery cell 10 will be discharged from the actuated part as emissions. In this way, the battery cell 10 can be depressurized and cooled under controllable pressure or temperature, thereby reducing the potential for more serious accidents.

[0101] In some embodiments, when the housing 11 is a non-sealed structure, the pressure relief mechanism 14 can be configured as a through hole for discharging the gas inside the battery cell 10 .

[0102] The emissions from the battery cells 10 mentioned in the present application include, but are not limited to: electrolyte, dissolved or split positive and negative electrode sheets, fragments of separators, high-temperature and high-pressure gases generated by the reaction, flames, and the like.

[0103] The positive electrode tab and the negative electrode tab can be led out from the same end of the electrode sheet, or can be led out from opposite ends of the electrode sheet respectively.

[0104] The structures of the positive electrode tab and the negative electrode tab may be the same or different. Taking the positive electrode tab as an example, the positive electrode tab may include multiple positive electrode tab layers, and multiple positive electrode tab layers are stacked together to form the positive electrode tab. The positive electrode tab may include at least two parts, one part is located between the main body of the pole piece and the insulating member, and the other part is located between the insulating member and the electrode lead-out member.

[0105] The insulating member can insulate at least part of the pole ear from the end face of the main body, thereby reducing the risk of the pole ear being inserted into the main body when the battery cell 10 is affected by external impact, vibration, etc., thereby reducing the risk of short circuit of the battery cell 10, which is beneficial to improving the reliability of the battery cell 10.

[0106] The insulating member may be an integral structure or a split structure. As an example, the insulating member is formed by connecting a plurality of independently formed parts. As another example, the insulating member is integrally formed by stamping.

[0107] For example, the insulating part is a plastic part, and the insulating part which is a plastic part is integrally formed by injection molding. The processing of the plastic part is convenient, and the manufacturing cost of the plastic part is low.

[0108] In some embodiments of the present application, Figure 2 and Figure 3 As shown, the housing 11 includes a shell 112 and an end cover 111 . The shell 112 has an opening. The end cover 111 is connected to the shell 112 and closes the opening. The end cover 111 constitutes a first side wall. The pressure relief mechanism 14 is disposed on the end cover.

[0109] In some embodiments of the present application, the housing 11 may be a steel shell, an aluminum shell, a plastic shell (such as polypropylene), a composite metal shell (such as a copper-aluminum composite shell) or an aluminum-plastic film, etc. In some embodiments, the housing 11 may be a sealed structure or a non-sealed structure. As an example, when the housing 11 is a non-sealed structure, the housing 11 plays a role in protecting the electrode assembly, and a sealing bag is also included between the housing 11 and the electrode assembly, and the sealing bag is used to encapsulate the electrode assembly and the electrolyte. Specifically, the sealing bag may be a bag-shaped insulating member or an aluminum-plastic film. When the housing 11 is a sealed structure, it is used to encapsulate components such as the electrode assembly and the electrolyte. The housing 112 may be provided with one or more openings. One or more end caps 111 may also be provided.

[0110] In addition, the connection methods between the end cover 111 and the housing 112 include but are not limited to snap connection, bonding, welding or connection via a connector.

[0111] In some embodiments of the present application, Figure 2 and Figure 3 As shown, the battery cell 10 also includes an electrode terminal 12, which is provided on the end cap and electrically connected to the electrode assembly. The electrode terminal 12 is electrically connected to the pole tab of the electrode assembly. The electrode terminal 12 can be directly connected to the pole tab, or indirectly connected to the pole tab through a current collecting member. The electrode terminal 12 can be provided on the end cap 111, or on the housing 112. In the embodiment shown in the present application, the electrode terminal 12 is provided on the end cap 111.

[0112] like Figures 2 to 4 As shown, in some embodiments of the present application, a method for manufacturing a battery cell 10 is proposed, and the method for manufacturing the battery cell 10 includes: S10: determining a target film according to a current type of the electrolyte of the battery cell 10, wherein when the current type of the electrolyte is disposed on the target film, the target film is not corroded.

[0113] Specifically, the coding area 16 of the battery cell 10 is set on the outer surface of the battery cell 10 by laser engraving or the like, and the coding area 16 includes but is not limited to the QR code, digital code or letter code of the battery cell 10, so that the battery cell 10 can be identified by the coding area 16. The coding area 16 is set on the outer shell 11 of the battery cell 10, and can specifically be the shell 112 or the end cover 111 of the outer shell 11, such as Figure 2 and Figure 3 As shown, the code engraving area 16 is arranged on the end cover 111 of the housing 11 .

[0114] The electrolyte is provided to be filled into the interior of the battery cell 10 through the injection hole 13 of the battery cell 10. During the electrolyte filling process, the electrolyte remaining on the filling device is easy to drip onto the battery cell 10. At the same time, when the battery cell 10 is formed, the electrolyte is easy to splash onto the outer surface of the battery cell 10 through the injection hole 13. The outer shell 11 of the battery cell 10 is usually made of metal material. The electrolyte is corrosive to the outer shell 11 of the metal material. When the electrolyte remains on the engraved area 16, the electrolyte will corrode the engraved area 16, so that the content of the engraved area 16 cannot be recognized, thereby affecting the production of the battery cell 10.

[0115] In the present application, in order to reduce the corrosion of the electrolyte on the code area 16 of the battery cell 10, a protective film 15 is pasted on the code area 16 of the battery cell 10 during the manufacture of the battery cell 10, so that the protective film 15 can be used to isolate the code area 16 from the outside world to reduce the corrosion of the electrolyte on the code area 16.

[0116] It should be understood that the protective film 15 pasted on the coding area 16 of the battery cell 10 needs to be able to resist corrosion from the electrolyte, that is, the electrolyte cannot corrode the protective film 15 , so that the protective film 15 is used to protect the coding area 16 , thereby reducing corrosion of the coding area 16 by the electrolyte.

[0117] Since there are many types of electrolytes for the battery cell 10 and different electrolytes have different corrosion capabilities, it is necessary to select a corresponding protective film 15 according to the type of electrolyte so that the protective film 15 can resist the corrosion of the electrolyte, thereby forming a better protection for the engraved area 16 of the battery cell 10.

[0118] In step S10 , the target film is determined according to the type of electrolyte of the battery cell 10 . When the target film is provided with the current type of electrolyte, the target film is not corroded. The target film is the film material of the processing protection film 15 .

[0119] The step S10 specifically includes: S11 : obtaining the current type of the electrolyte of the battery cell 10 .

[0120] Specifically, during the processing of the battery cell 10, the type of electrolyte is set according to the application scenario of the battery cell 10. Therefore, in order to make the protective film 15 have a good isolation effect on the electrolyte, it is necessary to know the type of electrolyte so as to further select the material of the protective film 15 according to the type of electrolyte, so that the protective film 15 finally pasted on the coding area 16 can provide better protection for the coding area 16.

[0121] S12: preparing a plurality of sample films according to the current type of electrolyte, wherein at least a plurality of sample films are made of different materials.

[0122] Specifically, during the manufacturing process of the battery cell 10, after knowing the type of electrolyte of the battery cell 10, multiple sample films are prepared for the type of electrolyte, and the materials of any two sample films are different. According to the type of electrolyte of the current battery cell 10, multiple sample films with different materials are set to provide multiple samples for the selection of the protective film 15, so that the protective film 15 that meets the electrolyte of the current battery cell 10 can be quickly obtained, thereby speeding up the production rhythm and effectively improving the production efficiency.

[0123] S13: testing a plurality of sample films, and determining a target film from the plurality of sample films according to the test data.

[0124] Specifically, multiple sample membranes are tested, the test data are recorded during the test, and the multiple sample membranes are screened based on the test data, so as to screen out the sample membranes that meet the requirements of the current electrolyte type from the multiple sample membranes, and determine the sample membranes that meet the requirements of the current electrolyte type as the target membrane.

[0125] Through steps S11 to S13, a plurality of sample films with different materials are prepared according to the current type of electrolyte of the battery cell 10, and the plurality of sample films are tested, and the target film is determined according to the test data. Such a setting can make the target film effectively adapt to the battery cell 10, thereby reducing the corrosion of the coding area 16 after the electrolyte corrodes the protective film 15.

[0126] In some implementations of the present application, in step S13, specifically also includes: S131: Perform corrosion tests on multiple sample films using the current type of electrolyte.

[0127] Specifically, when testing multiple sample films, it includes performing corrosion tests on multiple sample films. During the corrosion test, the electrolyte of the battery cell 10 to be manufactured is used as the corrosion liquid, and the corrosion liquid is dropped onto multiple sample films respectively, and maintained for a certain period of time (for example, 1 minute, 2 minutes, 3 minutes, 4 minutes, 5 minutes, 6 minutes, 7 minutes, 8 minutes, 9 minutes, etc.), and the corrosion data (for example, corrosion depth, etc.) of the multiple sample films are recorded, and multiple sample films are selected according to the corrosion data so that the selected sample films can resist the corrosion of the electrolyte.

[0128] S132: According to the fact that the sample film is not corroded by the current type of electrolyte, a sample film that is preliminarily qualified is determined from a plurality of sample films.

[0129] Specifically, during the corrosion test, multiple sample films are screened through corrosion data. In order to make the protective film 15 have good corrosion resistance, during the corrosion test, the sample films that are not corroded by the electrolyte (for example, the sample films with a corrosion depth of 0) are screened out, so that the sample films that are not corroded by the electrolyte can be used as preliminary qualified sample films, thereby improving the resistance to the electrolyte.

[0130] S133: Review the preliminarily qualified sample films and determine the target film from the preliminarily qualified sample films to see if they meet the design requirements based on the review parameters, wherein the design requirements include at least one of transmittance, thickness, temperature resistance, release force and insulation.

[0131] Specifically, corrosion tests are used to screen multiple sample films to select preliminarily qualified sample films. In order to make the preliminarily qualified sample films better meet the use requirements of the battery cell 10, the preliminarily qualified sample films are screened through review so as to further improve the quality of the protective film 15 so that the protective film 15 can effectively meet the use requirements of the battery cell 10.

[0132] Through steps S131 to S133, in the process of testing multiple sample films, the corrosion test can be used to directly screen out the sample films that can resist the electrolyte of the battery cell 10, and then the screened sample films are reviewed, and the sample films that pass the review are determined as the target films. Such a setting can effectively improve the quality of the protective film 15, so that the protective film 15 can meet the current use requirements of the battery cell 10.

[0133] In some embodiments of the present application, when the preliminarily qualified sample film is reviewed, the review content includes light transmittance, thickness, temperature resistance, release force and insulation, that is, in step S133, specifically includes: S1331: Testing the transmittance of the preliminarily qualified sample film, and determining the sample film with qualified transmittance based on the transmittance of the sample film being greater than or equal to a first threshold.

[0134] Specifically, the transmittance of the protective film 15 directly affects whether the coded area 16 can be effectively identified. The transmittance is a percentage, and the value range is 0 to 100%. The smaller the value, the worse the transmittance of the protective film 15 (at this time, the recognition effect of the coded area 16 is poor). Conversely, the larger the value, the better the transmittance of the protective film 15 (at this time, the recognition effect of the coded area 16 is good). Among them, the first threshold is used to represent the preset value of the transmittance of the protective film, which is a value between 0 and 100%.

[0135] During the review, the transmittance of the sample film is reviewed to ensure that the selected sample film has good transmittance, so that the content of the engraved area 16 of the battery cell 10 can be effectively identified through the protective film 15. During the review process, the first threshold is used as the critical value for screening, thereby improving the convenience of screening.

[0136] The first threshold is greater than or equal to 50% and less than or equal to 100%. This configuration enables the protective film 15 to have good light transmittance, reduces the shielding of the code area 16 of the battery cell 10, and enables effective identification of the code area 16, thereby meeting production requirements.

[0137] It should be noted that the first threshold may specifically be 50%, 60%, 70%, 80%, 90%, or 100%.

[0138] In the present application, the value range of the first threshold value can specifically be 70% to 100%. By setting it in this way, the protective film 15 can effectively reduce the manufacturing cost while having good light transmittance.

[0139] S1332: Testing the thickness of the preliminarily qualified sample film, and determining the sample film with qualified thickness based on the thickness of the sample film being less than or equal to a second threshold.

[0140] Specifically, the thickness of the protective film 15 directly affects the corrosion resistance, structural strength and manufacturing cost of the protective film 15. In the present application, the unit of the thickness of the protective film 15 is millimeter. When the thickness of the protective film 15 is larger, the corrosion resistance and structural strength are stronger, but the manufacturing cost is higher. When the thickness of the protective film 15 is smaller, the corrosion resistance and structural strength are worse, but the manufacturing cost is lower. Among them, the second threshold is used to characterize the preset value of the thickness of the protective film 15, and its unit is micron.

[0141] During the review, the thickness of the sample film is reviewed to ensure that the selected sample film has a suitable thickness, thereby reducing the manufacturing cost of the protective film 15 and also reducing the space occupied by the protective film 15. During the review process, the second threshold is used as the critical value for screening, thereby improving the convenience of screening.

[0142] The second threshold is greater than 0 micrometers and less than or equal to 150 micrometers. This configuration can effectively control the thickness of the protective film 15 while being able to resist corrosion from the electrolyte, thereby reducing the space occupied by the protective film 15 and the manufacturing cost of the protective film 15.

[0143] It should be pointed out that the second threshold may specifically be 1 micron, 10 microns, 20 microns, 30 microns, 40 microns, 50 microns, 60 microns, 100 microns, or 150 microns.

[0144] In the present application, the value range of the second threshold value can specifically be 50 microns to 100 microns. This setting allows the protective film 15 to effectively reduce the manufacturing cost while having good corrosion resistance and structural strength.

[0145] S1333: Testing the temperature resistance of the preliminarily qualified sample films, and determining the sample films with qualified temperature resistance based on the tolerance temperature of the sample films being greater than or equal to a third threshold.

[0146] Specifically, the temperature tolerance of the protective film 15 directly affects the temperature resistance of the protective film 15. In the present application, the unit of the temperature tolerance of the protective film 15 is degrees Celsius. When the temperature tolerance of the protective film 15 is higher, the temperature resistance is stronger. When the temperature tolerance of the protective film 15 is lower, the temperature tolerance is worse. Among them, the third threshold is used to characterize the preset value of the temperature tolerance of the protective film 15, and its unit is degrees Celsius.

[0147] During the review, the temperature resistance of the sample film is reviewed to ensure that the selected sample film has appropriate temperature resistance, so that the protective film 15 can have good temperature resistance to reduce the impact of temperature on the protective film 15. During the review process, the third threshold is used as the critical value for screening, thereby improving the convenience of screening.

[0148] The third threshold is greater than or equal to 300 degrees Celsius and less than or equal to 400 degrees Celsius. This configuration enables the protective film 15 to have the ability to withstand high temperatures, thereby reducing the adverse effects of welding heat on the protective film 15 when the battery cell 10 is welded.

[0149] It should be pointed out that the third threshold may specifically be 300 degrees Celsius, 310 degrees Celsius, 320 degrees Celsius, 330 degrees Celsius, 340 degrees Celsius, 350 degrees Celsius, 360 degrees Celsius, 370 degrees Celsius, 380 degrees Celsius, 390 degrees Celsius, or 400 degrees Celsius.

[0150] In the present application, the value range of the third threshold value can specifically be 350 degrees Celsius to 400 microns. This setting allows the protective film 15 to effectively reduce the manufacturing cost while having good temperature resistance.

[0151] S1334: testing the release force of the preliminarily qualified sample film, and determining the sample film with qualified release force according to the release force of the sample film being greater than or equal to a fourth threshold.

[0152] Specifically, the release force of the protective film 15 directly affects the fixing strength of the protective film 15. In the present application, the unit of the release force of the protective film 15 is Newton / 25 mm (that is, along the length direction of the protective film 15, with a length of 25 mm as a unit, that is, the release force of the protective film 15 per 25 mm length). When the release force of the protective film 15 is greater, the fixing strength is greater, and when the release force of the protective film 15 is smaller, the fixing strength is worse. Among them, the fourth threshold is used to characterize the preset value of the release force of the protective film 15, and its unit is Newton / 25 mm.

[0153] During the review, the release force of the sample film is reviewed to ensure that the selected sample film has a suitable release force, so that the protective film 15 has sufficient strength after being pasted to reduce the situation where the protective film 15 falls off. During the review process, the fourth threshold is used as the critical value for screening, thereby improving the convenience of screening.

[0154] The fourth threshold is greater than or equal to 1 Newton / 25 millimeters and less than or equal to 10 Newtons / 25 millimeters. This configuration enables the protective film 15 to have good structural strength after being attached, thereby reducing the possibility of the protective film 15 falling off.

[0155] It should be pointed out that the fourth threshold can specifically be 1 N / 25 mm, 2 N / 25 mm, 3 N / 25 mm, 4 N / 25 mm, 5 N / 25 mm, 6 N / 25 mm, 7 N / 25 mm, 8 N / 25 mm, 9 N / 25 mm, and 10 N / 25 mm.

[0156] In the present application, the value range of the fourth threshold may specifically be 5 N / 25 mm to 10 N / 25 mm. By setting it in this way, the protective film 15 can effectively reduce the manufacturing cost while having a fixed strength.

[0157] S1335: Testing the insulation of the preliminarily qualified sample film, and determining the sample film with qualified resistance based on the resistance value of the sample film being greater than or equal to a fifth threshold.

[0158] Specifically, the resistance value of the protective film 15 directly affects the insulation performance of the protective film 15. In the present application, the unit of the resistance value of the protective film 15 is ohm. When the resistance value of the protective film 15 is larger, the insulation performance is greater. When the resistance value of the protective film 15 is smaller, the insulation performance is worse. Among them, the fifth threshold is used to characterize the preset value of the resistance value of the protective film 15, and its unit is ohm.

[0159] During the review, the insulation of the sample film is reviewed to ensure that the selected sample film has appropriate insulation, so that the protective film 15 has good insulation, and the situation that the conductive protective film 15 causes short circuits in other components is reduced. In the review process, the fifth threshold is used as the critical value for screening, thereby improving the convenience of screening.

[0160] The fifth threshold is greater than 10 to the fifth power ohms and less than or equal to 10 to the tenth power ohms. This configuration enables the protective film 15 to have good insulation properties, thereby reducing the situation where the protective film 15 is conductive and causes short circuits in other components.

[0161] It should be pointed out that the fifth threshold value can specifically be 10 to the 5th power ohms, 10 to the 6th power ohms, 10 to the 7th power ohms, 10 to the 8th power ohms, 10 to the 9th power ohms, or 10 to the 10th power ohms.

[0162] In the present application, the value range of the fifth threshold value can specifically be 10 to the power of 6 ohms to 10 to the power of 10 ohms. By setting it in this way, the protective film 15 can effectively reduce the manufacturing cost while having better insulation performance.

[0163] Through steps S1331 to S1335, when reviewing the preliminarily qualified sample film, the preliminarily qualified sample film is tested respectively in terms of transmittance, thickness, temperature resistance, release force and insulation, so that the determined target film's transmittance, thickness, temperature resistance, release force and insulation meet the use requirements of the battery cell 10, so that the protective film 15 can be effectively adapted to the battery cell 10.

[0164] S20 : ​​determining processing parameters according to the structural parameters of the code engraving area 16 of the battery cell 10 .

[0165] Specifically, the coding area 16 is disposed on the outer surface of the battery cell 10 , and the protective film 15 is disposed on the outer surface of the battery cell 10 by pasting and covers the entire coding area 16 . Therefore, the structural parameters of the coding area 16 are the basis for processing the protective film 15 .

[0166] Among them, the structural parameters of the coding area 16 are measured or the structural parameters include but are not limited to shape and size. The processing parameters are determined according to the structural parameters of the coding area 16, so that the processed protective film 15 can be more matched with the coding area 16, thereby effectively isolating the coding area 16 from the outside, thereby reducing the corrosion of the coding area 16 caused by the electrolyte.

[0167] Furthermore, the structural parameters include the shape of the coding area 16 and the size of the coding area 16 , and the processing parameters include the shape of the protective film 15 and the size of the protective film 15 , wherein the shape of the protective film 15 is consistent with the shape of the coding area 16 , and the size of the protective film 15 is greater than or equal to the size of the coding area 16 .

[0168] Such a configuration can make the protective film 15 effectively fit the code area 16 , and on the basis of effectively protecting the code area 16 , can reduce the amount of the protective film 15 used, so that the manufacturing cost of the battery cell 10 can be reduced. Furthermore, the size of the protective film 15 is greater than or equal to the size of the coding area 16. When the protective film 15 is pasted on the outer surface of the battery cell 10, the entire coding area 16 is covered by the protective film 15, and the minimum distance between the edge of the coding area 16 and the edge of the protective film 15 is greater than or equal to 0 mm and less than or equal to 2 mm.

[0169] Such a configuration enables the protective film 15 to be effectively matched with the code area 16 , and on the basis of effectively protecting the code area 16 , the amount of the protective film 15 can be reduced, so that the manufacturing cost of the battery cell 10 can be reduced.

[0170] It should be noted that the minimum distance between the edge of the engraved area 16 and the edge of the protective film 15 can be 0 mm, 0.5 mm, 0.8 mm, 1 mm, 1.2 mm, 1.5 mm, 1.8 mm, or 2 mm.

[0171] In the present application, the minimum distance between the edge of the coding area 16 and the edge of the protective film 15 can specifically range from 0.8 mm to 1.2 mm. This setting allows the protective film 15 to effectively reduce the manufacturing cost while providing better protection for the coding area 16.

[0172] like Figure 3 As shown, in Figure 3 In the embodiment, the code engraving area 16 is a rectangular structure, the protective film 15 is also a rectangular structure, and the size of the protective film 15 is larger than the size of the code engraving area 16. Figure 3 In the figure, along the first direction (horizontal direction in the figure), the minimum distance between the edge of the protective film 15 and the edge of the code area 16 is a first distance a, and along the second direction (vertical direction in the figure), the minimum distance between the edge of the protective film 15 and the edge of the code area 16 is a second distance b. By setting the protective film 15, the protective film 15 can fully cover the code area 16, further reducing the situation where the electrolyte penetrates through the edge into the space between the protective film 15 and the code area 16, thereby corroding the code area 16.

[0173] S30: Processing the target film into a protective film 15 according to processing parameters.

[0174] Specifically, the method of processing the target film into the protective film 15 is cutting. Such a configuration facilitates processing of the target film, can effectively improve processing efficiency, and speed up the production cycle.

[0175] S40 : bonding the protection film 15 to the outer surface of the battery cell 10 , so that the code area 16 is covered by the protection film 15 .

[0176] Specifically, after the protective film 15 is processed, the protective film 15 is connected to the outer surface of the battery cell 10 by bonding, so that the protective film 15 covers the coding area 16 of the battery cell 10, and the protective film 15 is used to isolate the coding area 16 from the outside world, so as to reduce the adverse effects of electrolyte and the like on the coding area 16, thereby meeting the production needs.

[0177] The protective film 15 is bonded and fixed to the outer surface of the battery cell 10 . The bonding method has a simple structure and is easy to implement, which can effectively speed up the production rhythm and improve the production efficiency.

[0178] In some implementations of the present application, in step S40, specifically including: S41 : receiving and fixing the battery cell 10 .

[0179] Specifically, when pasting the protective film 15 to the coding area 16 of the battery cell 10, the battery cell 10 is first placed on a corresponding fixture, and the battery cell 10 is fixed by the fixture to maintain the position of the battery cell 10, thereby facilitating the positioning of the protective film 15 during the process of pasting it to the battery cell 10, thereby improving the accuracy of pasting the protective film 15.

[0180] S42 : obtaining the current state of the outer surface of the battery cell 10 having the code area 16 .

[0181] Specifically, before attaching the protective film 15 to the battery cell 10, it is necessary to obtain the current state of the outer surface of the battery cell 10 to which the protective film 15 is attached, so as to eliminate factors that affect the attachment of the protective film 15, such as residual electrolyte, dust or other foreign matter at the attachment position.

[0182] When there is foreign matter at the position of the battery cell 10 where the protective film 15 is pasted, the foreign matter needs to be removed before pasting the protective film 15 , thereby improving the fit between the protective film 15 and the battery cell 10 and improving the pasting effect of the protective film 15 .

[0183] S43 : according to the fact that no electrolyte remains on the outer surface of the battery cell 10 having the code area 16 , controlling the protective film 15 to be attached to the outer surface of the battery cell 10 so that the entire code area 16 is covered by the protective film 15 .

[0184] Specifically, the protective film 15 is attached to the battery cell 10 and covers the entire code area 16, and its purpose is to isolate the code area 16 from the electrolyte. When the protective film 15 is not attached, if there is residual electrolyte in the code area 16, it will corrode the code area 16. Therefore, it is necessary to discharge the residual electrolyte in the code area 16, that is, before attaching the protective film 15, it is necessary to keep the code area 16 free of residual electrolyte, so as to reduce the corrosion of the code area 16 by the electrolyte.

[0185] Through steps S41 to S43, when the protective film 15 is pasted on the battery cell 10, the battery cell 10 is first fixed, and then the surface of the battery cell 10 having the coding area 16 is detected to see whether there is any residual electrolyte. After confirming that there is no residual electrolyte, the protective film 15 is pasted on the battery cell 10, thereby reducing the situation where there is residual electrolyte between the protective film 15 and the battery cell 10.

[0186] In some implementations of the present application, in step S43, specifically also includes: S431: Acquire the current position of the code engraving area 16.

[0187] Specifically, after the battery cell 10 is fixed, the protective film 15 is pasted on the outer surface of the battery cell 10 having the coding area 16. Therefore, it is necessary to know the current position of the coding area 16 so that the protective film 15 can be accurately pasted on the outer surface of the battery cell 10 having the coding area 16 and completely cover the coding area 16.

[0188] S432 : Control the protective film 15 to be disposed above the code engraving area 16 .

[0189] Specifically, in the process of bonding the protective film 15, the protective film 15 is moved to the position of the coding area 16 of the battery cell 10, and is spaced above the coding area 16 so that the protective film 15 is opposite to the coding area 16, so that the protective film 15 can be adhered to the battery cell 10 by vertically moving the protective film 15 and the entire protective film 15 is covered.

[0190] S433: Control the protective film 15 to rotate about a preset rotation axis to adjust the angle of the protective film 15, wherein the preset rotation axis is perpendicular to the plane where the code area 16 is located. By rotating the protective film 15, the angle of the protective film 15 relative to the code area 16 is controlled within a reasonable range (the relative angle between the protective film 15 and the code area 16 is 0 degrees or close to 0 degrees), thereby improving the pasting accuracy of the protective film 15.

[0191] S434: Control the translation of the protective film 15 so that the projection of the protective film 15 on the battery cell 10 can cover the entire code area 16, wherein the translation direction of the protective film 15 is parallel to the code area 16. By translating the protective film 15, the position of the protective film 15 relative to the code area 16 is controlled within a reasonable range, and the exposure of the code area 16 to the outside of the protective film 15 is reduced, thereby improving the adhesion accuracy of the protective film 15.

[0192] S435 : The control protection film 15 is adhered to the outer surface of the battery cell 10 to cover the entire code area 16 .

[0193] Specifically, during the process of sticking the protective film 15 , the protective film 15 is moved downward until the protective film 15 is stuck on the outer surface of the battery cell 10 and completely covers the engraved code area 16 .

[0194] It should be understood that the protective film 15 is adhered and fixed to the outer surface of the battery cell 10 , wherein the protective film 15 may have its own adhesive layer, or the adhesive layer may be coated on the outer surface of the battery cell 10 .

[0195] Through steps S41 to S43, by controlling the angle and position of the protective film 15, the adhesion accuracy of the protective film 15 can be effectively improved, so that the protective film 15 can effectively protect the engraved area 16, further reducing the corrosion problem of the engraved area 16 caused by the electrolyte.

[0196] In some implementations of the present application, in step S43, specifically also includes: S436 : The control protection film 15 is attached to the outer surface of the battery cell 10 .

[0197] Specifically, during the process of sticking the protective film 15 , the protective film 15 is moved downward until the protective film 15 is stuck on the outer surface of the battery cell 10 and completely covers the engraved code area 16 .

[0198] S437 : applying a preset pressure to the side of the protection film 15 facing away from the battery cell 10 .

[0199] Specifically, the preset pressure refers to the pressure applied to the side of the protective film 15 facing away from the battery cell 10 , and the pressure is a set value, and its unit is Newton.

[0200] After the protective film 15 is attached to the outer surface of the battery cell 10 , pressure is applied to the protective film 15 so that the protective film 15 can be in close contact with the outer surface of the battery cell 10 , thereby increasing the bonding strength and improving the stability of the protective film 15 after attachment.

[0201] In some embodiments of the present application, the pressure exerted on the protective film 15 by the preset pressure is in the range of 0.4 MPa to 0.6 MPa.

[0202] Specifically, during the pasting process of the protective film 15, by setting the pressure exerted on the protective film 15 by the preset pressure within the range of 0.4 MPa to 0.6 MPa, the protective film 15 can have sufficient pasting strength during the pasting process while reducing the possibility of squeezing and deformation of the battery cell 10.

[0203] It should be pointed out that the pressure exerted on the protective film 15 by the preset pressure may specifically be 0.4 MPa, 0.45 MPa, 0.5 MPa, 0.55 MPa, or 0.6 MPa.

[0204] S438: When the duration of pressure on the protective film 15 reaches a preset duration, the preset pressure on the protective film 15 is released.

[0205] Specifically, the preset time length refers to the time length for which pressure is applied to the side of the protective film 15 facing away from the battery cell 10 and is maintained on the protective film 15 , and the unit is seconds.

[0206] By setting the duration of the pressure application of the protective film 15, during the process of the protective film 15 being pasted, the protective film 15 and the battery cell 10 can have good adhesion strength, thereby improving the adhesion effect of the battery cell 10. In some embodiments of the present application, the preset time is within a range of 5 seconds to 25 seconds. Specifically, by setting the preset time within a range of 5 seconds to 25 seconds, the protective film 15 and the battery cell 10 can have good adhesion strength during the adhesion process of the protective film 15, thereby further improving the adhesion effect of the battery cell 10.

[0207] It should be pointed out that the specific value of the preset duration can be 5 seconds, 7 seconds, 9 seconds, 10 seconds, 13 seconds, 15 seconds, 17 seconds, 20 seconds, 22 seconds, 24 seconds, and 25 seconds.

[0208] Through steps S436 to S438, during the process of pasting the protective film 15, by setting a preset pressure and a preset time, the protective film 15 can be pasted under the action of the pasting pressure, thereby improving the pasting strength of the protective film 15 and further reducing the possibility of the protective film 15 falling off.

[0209] In the present application, according to the current type of electrolyte of the processed battery cell 10, a target film adapted to the electrolyte is selected, that is, the target film cannot be corroded by the electrolyte, and the target film is processed into the protective film 15 required by the battery cell 10, and then the processed protective film 15 is pasted to the outer surface of the battery cell 10 and covers the engraved area 16 to isolate the engraved area 16 from the outside. When the electrolyte splashes, the protective film 15 blocks the engraved area 16, and the electrolyte cannot fall on the engraved area 16, thereby effectively reducing the occurrence of electrolyte corrosion of the engraved area 16, so that the engraved area 16 can be effectively identified, thereby effectively satisfying the improvement of the qualified rate of the battery cell 10.

[0210] For example, taking the organic electrolyte with LiPF6 as the most widely used solute in power battery manufacturing, the solvent is mostly ester compounds, which have a low risk of corrosion to the aluminum shell. The main corrosion risk is the hydrofluoric acid (HF) generated by the reaction of LiPF6 with water. For hydrofluoric acid corrosion, polyimide (PI) tape with high corrosion resistance can be selected. Polyimide is one of the organic polymer materials with the best comprehensive performance. It has excellent properties such as high temperature resistance (400 degrees Celsius), high insulation, acid and alkali corrosion resistance, and high light transmittance (greater than 90%), which can well adapt to the needs of the protective film 15 of the engraved area 16.

[0211] In the production process of the battery cell 10 , the above-mentioned method for manufacturing the battery cell 10 is implemented through a battery production line.

[0212] The second aspect of the present application proposes an end cap assembly, which includes an end cap 111 and a protective film 15. The outer surface of the end cap 111 is provided with a coding area 16. The protective film 15 is the protective film 15 as described above. The protective film 15 is adhered to the outer surface of the end cap 111 and covers the coding area 16.

[0213] Specifically, during the processing of the battery cell 10, according to the current type of electrolyte of the processed battery cell 10, a target film that is compatible with the electrolyte is selected, that is, the target film cannot be corroded by the electrolyte, and the target film is processed into the protective film 15 required by the battery cell 10, and then the processed protective film 15 is pasted to the outer surface of the battery cell 10 and covers the code area 16 to isolate the code area 16 from the outside. When the electrolyte splashes, the protective film 15 blocks the code area 16, and the electrolyte cannot fall on the code area 16, thereby effectively reducing the occurrence of electrolyte corrosion of the code area 16, so that the code area 16 can be effectively identified, thereby effectively meeting the requirement of improving the qualified rate of the battery cell 10.

[0214] A third aspect of the present application provides a battery cell 10 , which is manufactured by the above battery production line.

[0215] Specifically, when processing the battery cell 10, according to the current type of electrolyte of the processed battery cell 10, a target film that is compatible with the electrolyte is selected, that is, the target film cannot be corroded by the electrolyte, and the target film is processed into the protective film 15 required by the battery cell 10, and then the processed protective film 15 is pasted to the outer surface of the battery cell 10 and covers the engraved area 16 to isolate the engraved area 16 from the outside. When the electrolyte splashes, the protective film 15 blocks the engraved area 16, and the electrolyte cannot fall on the engraved area 16, thereby effectively reducing the occurrence of electrolyte corrosion of the engraved area 16, so that the engraved area 16 can be effectively identified, thereby effectively meeting the requirement of improving the qualified rate of the battery cell 10.

[0216] A fourth aspect of the present application provides a battery device 100 , which includes the battery cell 10 as described above.

[0217] Specifically, when processing the battery cell 10, according to the current type of electrolyte of the processed battery cell 10, a target film that is compatible with the electrolyte is selected, that is, the target film cannot be corroded by the electrolyte, and the target film is processed into the protective film 15 required by the battery cell 10, and then the processed protective film 15 is pasted to the outer surface of the battery cell 10 and covers the engraved area 16 to isolate the engraved area 16 from the outside. When the electrolyte splashes, the protective film 15 blocks the engraved area 16, and the electrolyte cannot fall on the engraved area 16, thereby effectively reducing the occurrence of electrolyte corrosion of the engraved area 16, so that the engraved area 16 can be effectively identified, thereby effectively meeting the requirement of improving the qualified rate of the battery cell 10.

[0218] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below.

[0219] In the implementation mode of the present application, Figures 2 to 4 As shown, the present application proposes a method for manufacturing a battery cell 10, and the method for manufacturing the battery cell 10 includes: S10: determining a target film according to a current type of the electrolyte of the battery cell 10, wherein when the current type of the electrolyte is disposed on the target film, the target film is not corroded.

[0220] The step S10 specifically includes obtaining the current type of electrolyte of the battery cell 10, preparing a plurality of sample films according to the current type of electrolyte, wherein at least a plurality of sample films have different materials, testing the plurality of sample films, and determining a target film among the plurality of sample films according to the test data.

[0221] Furthermore, the step of testing a plurality of film samples and determining a target film among the plurality of film samples based on the test data includes performing corrosion tests on the plurality of film samples using a current type of electrolyte, determining preliminarily qualified film samples among the plurality of film samples based on the fact that the film samples are not corroded by the current type of electrolyte, reviewing the preliminarily qualified film samples and determining a target film among the preliminarily qualified film samples based on whether the review parameters meet the design requirements, wherein the design requirements include at least one of transmittance, thickness, temperature resistance, release force and insulation.

[0222] Furthermore, in reviewing the preliminarily qualified sample film and satisfying the design requirements based on the review parameters, the step of determining the target film from the preliminarily qualified sample film includes testing the transmittance of the preliminarily qualified sample film, and determining a sample film with qualified transmittance based on the transmittance of the sample film being greater than or equal to a first threshold value, testing the thickness of the preliminarily qualified sample film, and determining a sample film with qualified thickness based on the thickness of the sample film being less than or equal to a second threshold value, testing the temperature resistance of the preliminarily qualified sample film, and determining a sample film with qualified temperature resistance based on the temperature resistance of the sample film being greater than or equal to a third threshold value, testing the release force of the preliminarily qualified sample film, and determining a sample film with qualified release force based on the release force of the sample film being greater than or equal to a fourth threshold value, testing the insulation of the preliminarily qualified sample film, and determining a sample film with qualified resistance based on the resistance value of the sample film being greater than or equal to a fifth threshold value.

[0223] Among them, the first threshold is greater than or equal to 70% and less than or equal to 100%. The second threshold is greater than 50 microns and less than or equal to 100 microns. The third threshold is greater than or equal to 350 degrees Celsius and less than or equal to 400 degrees Celsius. The fourth threshold is greater than or equal to 5 Newtons / 25 millimeters and less than or equal to 10 Newtons / 25 millimeters. The fifth threshold is greater than 10 to the sixth power ohms and less than or equal to 10 to the tenth power ohms.

[0224] S20 : ​​determining processing parameters according to the structural parameters of the code engraving area 16 of the battery cell 10 .

[0225] The step S20 includes the step of determining processing parameters according to the structural parameters of the coding area 16 of the battery cell 10, wherein the structural parameters include the shape of the coding area 16 and the size of the coding area 16, and the processing parameters include the shape of the protective film 15 and the size of the protective film 15, wherein the shape of the protective film 15 is consistent with the shape of the coding area 16, and the size of the protective film 15 is greater than or equal to the size of the coding area 16. The size of the protective film 15 is greater than or equal to the size of the coding area 16, and when the protective film 15 is attached to the outer surface of the battery cell 10, the entire coding area 16 is covered by the protective film 15, and the minimum distance between the edge of the coding area 16 and the edge of the protective film 15 is greater than or equal to 0.8 mm and less than or equal to 1.2 mm.

[0226] S30: According to the processing parameters, the target film is processed into the protective film 15. The method of processing the target film into the protective film 15 is cutting.

[0227] S40 : bonding the protection film 15 to the outer surface of the battery cell 10 , so that the code area 16 is covered by the protection film 15 .

[0228] The step S40 includes receiving and fixing the battery cell 10, obtaining the current state of the outer surface of the battery cell 10 having the coding area 16, and according to the fact that no electrolyte remains on the outer surface of the battery cell 10 having the coding area 16, controlling the protective film 15 to be adhered to the outer surface of the battery cell 10 so that the entire coding area 16 is covered by the protective film 15.

[0229] Furthermore, according to the fact that no electrolyte remains on the outer surface of the battery cell 10 having the coding area 16, the step of controlling the protective film 15 to be adhered to the outer surface of the battery cell 10 so that the entire coding area 16 is covered by the protective film 15 includes obtaining the current position of the coding area 16, controlling the protective film 15 to be disposed above the coding area 16, controlling the protective film 15 to rotate about a preset rotation axis to adjust the angle of the protective film 15, wherein the preset rotation axis is perpendicular to the plane where the coding area 16 is located, controlling the protective film 15 to translate so that the projection of the protective film 15 on the battery cell 10 can cover the entire coding area 16, wherein the translation direction of the protective film 15 is parallel to the coding area 16, and controlling the protective film 15 to be adhered to the outer surface of the battery cell 10 to cover the entire coding area 16.

[0230] Furthermore, the step of controlling the protective film 15 to be pasted onto the outer surface of the battery cell 10 to cover the entire coding area 16 includes controlling the protective film 15 to be pasted onto the outer surface of the battery cell 10, applying a preset pressure on the side of the protective film 15 away from the battery cell 10, and releasing the preset pressure on the protective film 15 when the pressure application time of the protective film 15 reaches a preset time.

[0231] The preset pressure exerts a pressure on the protective film 15 in a range of 0.4 MPa to 0.6 MPa, and the preset duration is in a range of 5 seconds to 25 seconds.

[0232] Specifically, according to the current type of electrolyte of the processed battery cell 10, a target film that is compatible with the electrolyte is selected, that is, the target film cannot be corroded by the electrolyte, and the target film is processed into the protective film 15 required by the battery cell 10, and then the processed protective film 15 is pasted to the outer surface of the battery cell 10 and covers the engraved area 16 to isolate the engraved area 16 from the outside. When the electrolyte splashes, the protective film 15 blocks the engraved area 16, and the electrolyte cannot fall on the engraved area 16, thereby effectively reducing the occurrence of electrolyte corrosion of the engraved area 16, so that the engraved area 16 can be effectively identified, thereby effectively meeting the requirement of improving the qualified rate of the battery cell 10.

[0233] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A method for manufacturing a battery cell, characterized in that: The manufacturing method of the battery cell comprises: Determining a target film according to a current type of electrolyte of the battery cell, wherein when the current type of electrolyte is disposed on the target film, the target film is not corroded; Determining processing parameters according to structural parameters of the coding area of ​​the battery cell; According to the processing parameters, processing the target film into a protective film; The protective film is adhered to the outer surface of the battery cell so that the engraved code area is covered by the protective film.

2. The method for manufacturing a battery cell according to claim 1, wherein: The step of determining the target membrane according to the current type of the electrolyte of the battery cell comprises: Obtaining the current type of electrolyte of the battery cell; According to the current type of electrolyte, preparing a plurality of sample films, wherein at least the materials of the plurality of sample films are different; The plurality of sample films are tested, and the target film is determined from the plurality of sample films according to the test data.

3. The method for manufacturing a battery cell according to claim 2, wherein: The testing of the plurality of sample films and determining the target film from the plurality of sample films according to the test data comprises: Performing corrosion tests on the plurality of sample films using the current type of electrolyte; According to the fact that the sample film is not corroded by the current type of electrolyte, determining the sample film that is preliminarily qualified from the multiple sample films; The sample films that are preliminarily qualified are reviewed and the design requirements are met according to the review parameters, and the target film is determined from the sample films that are preliminarily qualified, wherein the design requirements include at least one of transmittance, thickness, temperature resistance, release force and insulation.

4. The method for manufacturing a battery cell according to claim 3, wherein: The reviewing of the preliminarily qualified sample films and determining the target film from the preliminarily qualified sample films to determine whether the target film meets the design requirements according to the review parameters, comprises: Testing the transmittance of the preliminarily qualified sample film, and determining the sample film with qualified transmittance according to the transmittance of the sample film being greater than or equal to a first threshold; Testing the thickness of the preliminarily qualified sample film, and determining the sample film with qualified thickness according to the thickness of the sample film being less than or equal to a second threshold; Testing the temperature resistance of the preliminarily qualified sample film, and determining the sample film as having qualified temperature resistance according to the tolerance temperature of the sample film being greater than or equal to a third threshold; Testing the release force of the preliminarily qualified sample film, and determining the sample film with qualified release force according to the release force of the sample film being greater than or equal to a fourth threshold; The insulation of the preliminarily qualified sample film is tested, and the sample film with qualified resistance is determined according to the resistance value of the sample film being greater than or equal to a fifth threshold.

5. The method for manufacturing a battery cell according to claim 4, wherein: The first threshold is greater than or equal to 50% and less than or equal to 100%; And / or, the second threshold is greater than 0 micrometers and less than or equal to 150 micrometers; And / or, the third threshold is greater than or equal to 300 degrees Celsius and less than or equal to 400 degrees Celsius; And / or, the fourth threshold is greater than or equal to 1 N / 25 mm and less than or equal to 10 N / 25 mm; And / or, the fifth threshold is greater than 10 to the fifth power of ohms and less than or equal to 10 to the tenth power of ohms.

6. The method for manufacturing a battery cell according to claim 1, wherein: In the step of determining processing parameters according to the structural parameters of the coding area of ​​the battery cell, the structural parameters include the shape of the coding area and the size of the coding area, and the processing parameters include the shape of the protective film and the size of the protective film, wherein the shape of the protective film is consistent with the shape of the coding area, and the size of the protective film is greater than or equal to the size of the coding area.

7. The method for manufacturing a battery cell according to claim 6, wherein: When the protective film is attached to the outer surface of the battery cell, the entire engraved area is covered by the protective film, and the minimum distance between the edge of the engraved area and the edge of the protective film is greater than or equal to 0 mm and less than or equal to 2 mm.

8. The method for manufacturing a battery cell according to claim 1, wherein: In the step of processing the target film into a protective film according to the processing parameters, the target film is processed into the protective film by cutting.

9. The method for manufacturing a battery cell according to any one of claims 1 to 8, characterized in that: The step of bonding the protective film to the outer surface of the battery cell so that the engraved code area is covered by the protective film comprises: receiving and fixing the battery cell; Acquire a current state of the outer surface of the battery cell having the code area; According to the fact that no electrolyte remains on the outer surface of the battery cell having the code area, the protective film is controlled to be attached to the outer surface of the battery cell so that the entire code area is covered by the protective film.

10. The method for manufacturing a battery cell according to claim 9, wherein: According to the fact that no electrolyte remains on the outer surface of the battery cell having the code area, controlling the protective film to be attached to the outer surface of the battery cell so that the entire code area is covered by the protective film comprises: Obtaining the current position of the engraving area; Controlling the protective film to be disposed above the code engraving area; Controlling the protective film to rotate about a preset rotation axis to adjust the angle of the protective film, wherein the preset rotation axis is perpendicular to the plane where the engraved area is located; Controlling the translation of the protective film so that the projection of the protective film on the battery cell can cover the entire code area, wherein the translation direction of the protective film is parallel to the code area; The protective film is controlled to be adhered to the outer surface of the battery cell to cover the entire code area.

11. The method for manufacturing a battery cell according to claim 10, wherein: The step of controlling the protective film to be attached to the outer surface of the battery cell to cover the entire coding area includes: Controlling the protective film to be attached to the outer surface of the battery cell; Applying a preset pressure on a side of the protective film facing away from the battery cell; According to the duration of the pressure applied to the protective film reaching a preset duration, the preset pressure on the protective film is released.

12. The method for manufacturing a battery cell according to claim 10, wherein: The pressure exerted by the preset pressure on the protective film is in the range of 0.4 MPa to 0.6 MPa; And / or, the preset duration is in the range of 5 seconds to 25 seconds.

13. An end cap assembly, characterized in that: The end cap assembly comprises: An end cover, wherein the outer surface of the end cover is provided with a code engraving area; A protective film, wherein the protective film is the protective film according to any one of claims 1 to 12, and the protective film is adhered to the outer surface of the end cover and covers the engraved area.

14. A battery cell, characterized in that: The battery cell includes the end cap assembly of claim 13 .

15. A battery device, characterized in that: The battery device includes the battery cell according to claim 14 .

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