Insulating protective coating for battery and preparation method thereof

Abstract

The present application provides an insulating protective coating for a battery and a preparation method thereof. The preparation method of the insulating protective coating for a battery comprises the following steps: cleaning the battery. Drying the cleaned battery. Electrostatically spraying the dried battery with the insulating coating. Curing the sprayed battery so that an insulating protective coating is formed on the battery shell. Electrostatic spraying of the battery with the insulating coating means that the charged insulating coating is uniformly adsorbed on the battery shell under the action of electrostatic force, which can effectively avoid the problem of bubbles. During the electrostatic spraying process, only the positions that do not require insulation need to be covered with a template, and there will be no overlapping areas in the remaining areas after electrostatic spraying. By curing the battery, a uniform, continuous, flat and smooth insulating protective coating is formed after the insulating coating is cured on the battery shell.

Description

Technical Field

[0001] The invention relates to the field of batteries, and in particular to an insulating protective coating for batteries and a preparation method thereof. Background Art

[0002] With the development of the new energy industry, lithium-ion batteries have been increasingly widely used due to their high energy density, long cycle life, good rate performance, safety and reliability.

[0003] However, during the production process of lithium-ion batteries, the shell needs to be insulated with a blue film, the main purpose of which is to insulate the battery cell. However, the method of applying an insulating protective coating has the following problems: 1. There are bubbles in the film. 2. The overlapping area of ​​the protective film affects the battery size. 3. Due to the accuracy requirements of the film, the efficiency of the film process is low, resulting in low battery production efficiency. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies in the prior art and to provide an insulating protective coating for a battery and a preparation method thereof which will not generate bubbles and will not have overlapping areas while being able to improve the production efficiency of the battery.

[0005] The objective of the present invention is achieved through the following technical solutions:

[0006] A method for preparing an insulating protective coating for a battery comprises the following steps:

[0007] Clean the battery;

[0008] Drying the cleaned battery;

[0009] Using the insulating coating to electrostatically spray the dried battery;

[0010] The battery after spraying is cured so that an insulating protective coating is formed on the shell of the battery.

[0011] In one embodiment, the specific steps of cleaning the battery are as follows:

[0012] The battery is cleaned with hot water.

[0013] In one embodiment, the water temperature of the hot water is 35°C to 50°C.

[0014] In one embodiment, the specific steps of drying the cleaned battery are:

[0015] The battery is dried using hot air.

[0016] In one embodiment, the temperature of the hot air is 110°C to 140°C.

[0017] In one embodiment, the specific operation steps of electrostatically spraying the dried battery with the insulating coating are as follows:

[0018] Performing a heating and fluidizing operation on the insulating coating to obtain a fluid insulating coating;

[0019] Performing a charging operation on the fluid insulating coating to obtain a charged insulating coating;

[0020] The charged insulating coating is subjected to an atomization spraying operation, so that the insulating protective coating is formed on the shell of the battery.

[0021] In one embodiment, the heating temperature of the heating fluidization operation is 100°C to 200°C.

[0022] In one embodiment, the specific operation steps of performing the electrification operation on the fluid insulating coating are:

[0023] The charged insulating coating is obtained by applying voltage to the fluid insulating coating through a high voltage device.

[0024] In one embodiment, the voltage value is 10kv~110kv.

[0025] An insulating protective coating is prepared by using the method for preparing an insulating protective coating for a battery according to any of the above embodiments.

[0026] Compared with the prior art, the present invention has at least the following advantages:

[0027] 1. The preparation method of the insulating protective coating for batteries of the present application first cleans the battery, that is, cleans the surface of the battery to remove foreign matter on the surface of the battery, so as to ensure the cleanliness of the surface of the battery. Secondly, the battery is dried to ensure the dryness of the surface of the battery, so as to facilitate the subsequent spraying operation. Then, the battery is electrostatically sprayed with an insulating coating, that is, the insulating coating with a charge is uniformly adsorbed on the battery shell under the action of electrostatic force, so that the problem of bubbles can be effectively avoided. Moreover, during the electrostatic spraying process, only the positions that do not require insulation need to be covered with a template, and there will be no overlapping areas in the remaining areas after electrostatic spraying. Finally, the battery is cured, that is, the insulating coating is cured on the battery shell to form a uniform, continuous, flat and smooth insulating protective coating.

[0028] 2. Compared with the traditional film-laminating process, the preparation method of the insulating protective coating for the battery of the present application utilizes the effect of electrostatic force to enable the insulating coating to be evenly adsorbed on the battery shell, which not only can meet the fitting accuracy of the insulating protective coating, but also can greatly shorten the production time of the battery, thereby effectively improving the production efficiency of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0030] Figure 1 is a flow chart of a method for preparing an insulating protective coating for a battery in one embodiment;

[0031] Figure 2 for Figure 1 The flowchart of the specific steps of S300 is shown;

[0032] Figure 3 for Figure 2 The specific step flow chart of S303 is shown;

[0033] Figure 4 A schematic diagram of the structure of an electrostatic spraying device in one embodiment;

[0034] Figure 5 A schematic diagram of the structure of a battery made using a conventional coating process;

[0035] Figure 6 The figure is a schematic diagram of the structure of a battery made by the method for preparing the insulating protective coating of the present application. DETAILED DESCRIPTION

[0036] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly understood.

[0037] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0039] The method for preparing an insulating protective coating for a battery provided in the present application comprises the following steps: washing the battery, drying the washed battery, electrostatically spraying the dried battery with the insulating coating, and curing the sprayed battery, so that an insulating protective coating is formed on the battery shell.

[0040] The above-mentioned method for preparing the insulating protective coating for batteries first cleans the battery, that is, cleans the surface of the battery to remove foreign matter on the surface of the battery, so as to ensure the cleanliness of the battery surface. Secondly, the battery is dried to ensure the dryness of the battery surface, so as to facilitate the subsequent spraying operation. Then, the battery is electrostatically sprayed with an insulating coating, that is, the insulating coating with an electric charge is uniformly adsorbed on the battery shell under the action of electrostatic force, so that the problem of bubbles can be effectively avoided. Moreover, during the electrostatic spraying process, only the positions that do not require insulation need to be covered with a template, and there will be no overlapping areas in the remaining areas after electrostatic spraying. Finally, the battery is cured, that is, the insulating coating is cured on the battery shell to form a uniform, continuous, flat and smooth insulating protective coating.

[0041] Furthermore, compared with the traditional film laminating process, the use of electrostatic force allows the insulating coating to be evenly adsorbed on the battery shell, which not only meets the laminating accuracy of the insulating protective coating, but also can greatly shorten the production time of the battery, thereby effectively improving the production efficiency of the battery.

[0042] See also Figure 1 In order to better understand the preparation method of the insulating protective coating for a battery of the present application, the preparation method of the insulating protective coating for a battery is further explained below:

[0043] A method for preparing an insulating protective coating for a battery according to one embodiment includes the following steps:

[0044] S100, cleaning the battery.

[0045] In this embodiment, the battery is cleaned, that is, dust or foreign matter on the surface of the battery is removed, so as to facilitate the smoothness of the subsequent insulating protective coating.

[0046] S200, drying the cleaned battery.

[0047] In this embodiment, the cleaned battery is dried, that is, the cleaning liquid remaining on the surface of the battery is dried, so that the surface dryness of the battery can be ensured, thereby effectively ensuring the flatness of the insulating protective coating.

[0048] S300, electrostatically spraying the dried battery with insulating paint.

[0049] In this embodiment, the battery is electrostatically sprayed with insulating paint, that is, the insulating paint with charge is uniformly adsorbed on the battery shell under the action of electrostatic force, which can effectively avoid the problem of bubbles. In addition, during the electrostatic spraying process, only the positions that do not need insulation need to be covered with a template, and the remaining areas do not have overlapping areas similar to thin films after electrostatic spraying.

[0050] S400, curing the battery after spraying, so that an insulating protective coating is formed on the shell of the battery.

[0051] In this embodiment, by curing the sprayed battery, the insulating coating is cured on the battery shell to form a uniform, continuous, flat and smooth insulating protective coating, which can not only shorten the production time of the battery, but also effectively improve the battery yield.

[0052] In one embodiment, the specific steps of cleaning the battery are as follows:

[0053] The battery is cleaned with hot water.

[0054] It should be noted that hot water is used to clean the surface of the battery, that is, hot water is sprayed on the battery shell so that dust or foreign matter on the battery shell is washed away with the water flow. This can ensure the cleanliness of the surface of the battery shell, effectively avoid dust or foreign matter causing uneven molding of the insulating protective coating, and thus ensure that the insulating protective coating is formed on the battery shell with good flatness.

[0055] In one embodiment, the water temperature of the hot water is 35°C to 50°C.

[0056] It should be noted that the water temperature of the hot water is controlled between 35°C and 50°C, which can clean the dust or foreign matter on the surface of the battery to a large extent, so that the surface of the battery shell maintains good cleanliness and flatness, thereby ensuring that the insulating protective coating is formed on the battery shell with good flatness.

[0057] In one embodiment, the specific steps of drying the cleaned battery are:

[0058] The battery is dried using hot air.

[0059] It should be noted that hot air is blown toward the battery shell so that the residual moisture on the battery shell is dried by the hot air, thereby ensuring the dryness of the battery shell surface to facilitate subsequent processes.

[0060] In one embodiment, the temperature of the hot air is 110°C to 140°C.

[0061] It should be noted that the temperature of the hot air is controlled between 110°C and 140°C. Under the premise of not affecting the battery performance, the residual moisture on the surface of the battery shell can be dried to a large extent, so that the battery shell maintains a good degree of dryness, thereby ensuring that the insulating protective coating is formed on the battery shell with good flatness and continuity.

[0062] See also Figure 2 In one embodiment, the specific operation steps of electrostatically spraying the dried battery with insulating coating are as follows:

[0063] S301, performing a heating and fluidizing operation on the insulating coating to obtain a fluid insulating coating;

[0064] S302, performing a charging operation on the fluid insulating coating to obtain a charged insulating coating;

[0065] S303, performing an atomization spraying operation on the charged insulating coating so that the insulating protective coating is formed on the shell of the battery.

[0066] It should be noted that the insulating coating is heated and fluidized to form a fluid insulating coating so that the insulating coating can flow. Then the fluid insulating coating is charged to form a charged insulating coating, that is, the insulating coating is charged. Finally, the charged insulating coating is atomized and sprayed on the battery housing, and the insulating coating is uniformly adsorbed on the battery housing under the action of electrostatic force, which makes the insulating protective coating formed by curing the insulating coating more uniform, continuous, flat and smooth, thereby effectively improving the yield rate of the battery.

[0067] In one embodiment, the specific operation steps of heating and fluidizing the insulating coating are:

[0068] The insulating coating in the coating pool is heated to obtain a fluid insulating coating.

[0069] It should be noted that the coating pool is a place for storing insulating coatings. By heating the coating pool, the insulating coating in the coating pool is heated and fluidized to form fluid-like insulating coating, so as to facilitate the transportation of the insulating coating.

[0070] In one embodiment, the heating temperature of the heating fluidization operation is 100° C. to 200° C. It should be noted that when the heating temperature is between 100° C. and 200° C., the insulating coating can be fluidized to form a fluid insulating coating, and the fluid insulating coating is easy to transport and transfer, and can be quickly transferred to the next process, thereby effectively shortening the spraying time, thereby effectively shortening the production time of the battery, and further improving the production efficiency of the battery.

[0071] In one embodiment, the specific operation steps of performing the electrification operation on the fluid insulating coating are:

[0072] The charged insulating coating is obtained by applying voltage to the fluid insulating coating through a high voltage device.

[0073] It should be noted that the fluid insulating coating is pressurized by a high-voltage device so that the insulating coating is negatively charged, and then the charged insulating coating can be evenly adsorbed on the surface of the battery shell under the action of electrostatic force. This ensures that the insulating coating has better uniformity, better continuity, better flatness and better smoothness after molding, thereby effectively improving the battery yield.

[0074] In one embodiment, the voltage value is 10kv to 110kv. It should be noted that the applied voltage value is controlled between 10kv and 110kv, which can make the insulating coating uniformly adsorbed on the battery shell, so that the insulating protective coating has better uniformity, better continuity, better flatness and better smoothness after forming, further improving the yield rate of the battery.

[0075] In one embodiment, after the step of heating the insulating coating in the coating pool to obtain the fluid insulating coating and before the step of applying voltage to the fluid insulating coating by a high-voltage device to obtain the charged insulating coating, the following steps are also included:

[0076] First, compressed air is input into the transport pipeline to form a negative pressure state in the transport pipeline;

[0077] Then, the fluid coating is transported through the transport pipe.

[0078] It should be noted that by allowing compressed air to flow into the transport pipeline, a negative pressure state is formed in the transport pipeline, so that the fluid insulating coating can be quickly transferred to the charging area through the transport pipeline for charging operation, and then the charged insulating coating is quickly transferred to the atomizing spraying area through the transport pipeline for atomizing spraying operation, so that the insulating coating can be quickly transferred, thereby effectively shortening the production time of the battery, and thus effectively improving the production efficiency of the battery. Furthermore, the charged insulating coating can be evenly adsorbed on the surface of the battery shell under the action of electrostatic force and compressed air, thereby ensuring that the insulating protective coating has good uniformity, good continuity, good flatness and good smoothness after forming, thereby effectively improving the yield rate of the battery.

[0079] In one embodiment, the flow rate of the compressed air is 5m / s to 30m / s, and the air pressure of the compressed air is 0.7MPa to 10MPa. It should be noted that when the flow rate of the compressed air is between 5m / s and 30m / s and the air pressure is between 0.7MPa and 10MPa, not only can a negative pressure state be formed in the transport pipeline, but also the fluid insulating coating can be transported. Further, under the action of the compressed air flow rate of 5m / s to 30m / s and the air pressure of 0.7MPa to 10MPa, and at the same time with the action of electrostatic force, the insulating coating can be quickly and evenly attached to the surface of the battery shell, so that the insulating protective coating has better uniformity, better continuity, better flatness and better smoothness after forming, further improving the battery yield.

[0080] See also Figure 3 In one embodiment, the specific operation steps of atomizing and spraying the charged insulating coating are as follows:

[0081] S303a, placing the battery in a processing fixture, and passing a high voltage positive charge through the processing fixture;

[0082] S303b, passing high voltage negative electricity into the nozzle of the atomizing device, so that the processing fixture and the atomizing device form an electrostatic field;

[0083] S303c, the charged insulating coating is sprayed onto the battery casing through the nozzle of the atomizing device.

[0084] It should be noted that, first, by placing the battery in a processing fixture and passing high-voltage positive electricity to the processing fixture, the battery shell is positively charged. Then, by passing high-voltage negative electricity to the nozzle of the atomizing device, an electrostatic field is formed between the processing fixture and the atomizing device. Due to the electrostatic repulsion force of the electrostatic field (like repels like) and the action of compressed air, the insulating coating with negative charge can be quickly sprayed out from the atomizing device. Because of the electrostatic adsorption force of the electrostatic field (opposites attract each other) and the action of compressed air, the insulating coating with negative charge can be evenly adsorbed on the battery shell. In this way, the production time of the battery can be effectively shortened, and at the same time, the insulating protective coating has better uniformity, better continuity, better flatness and better smoothness after molding, thereby effectively improving the production efficiency and yield rate of the battery.

[0085] In one embodiment, the atomization spray speed of the atomization device is 5m / s to 30m / s. It should be noted that when the atomization spray speed is between 5m / s and 30m / s, the atomization device can quickly and evenly spray the insulating coating toward the processing fixture, and under the action of electrostatic force and compressed air, the insulating coating can be quickly and evenly attached to the surface of the battery shell, so that the insulating protective coating has better uniformity, better continuity, better flatness and better smoothness after forming, thereby effectively improving the production efficiency and yield rate of the battery.

[0086] See also Figure 4 The present application also provides an electrostatic spraying device 10, including a paint pool 100, a transport pipeline 200, a high-pressure device 300, an atomizing device 400 and a processing fixture 500, wherein a storage cavity 102 is formed in the paint pool 100, a heating device (not shown) is provided in the paint pool 100, the paint pool 100 is connected to one end of the transport pipeline 200, the transport pipeline 200 is provided with an air vent 202, the air vent 202 is used for an external compressed air source, the high-pressure device 300 is arranged on the transport pipeline 200, the atomizing device 400 is connected to the other end of the transport pipeline 200, and the nozzle of the atomizing device 400 is arranged toward the processing fixture 500.

[0087] In this embodiment, the insulating coating is stored in the storage chamber 102 of the coating pool 100, and the insulating coating is heated and fluidized by controlling the heating device to form a fluid insulating coating. Then, compressed air is input into the vent 202 to form a negative pressure state in the transport pipe 200, so that the fluid insulating coating can be transported from the coating pool 100 to the atomizing device 400 through the transport pipe 200. During the transportation process, the fluid insulating coating in the transport pipe 200 is pressurized with high voltage by the high-voltage device 300 to obtain an insulating coating with a negative charge. Further, a battery is placed in a processing fixture 500 and a high-voltage positive charge is passed through the processing fixture 500, and a high-voltage negative charge is passed through the nozzle of the atomizing device 400, so that the processing fixture 500 and the atomizing device 400 form an electrostatic field, and under the action of the electrostatic repulsion of the electrostatic field and the compressed air, the insulating coating with a negative charge can be quickly ejected from the atomizing device 400. Since the nozzle of the atomizing device 400 is disposed toward the processing fixture 500 and the negatively charged insulating coating can be uniformly adsorbed on the battery shell under the action of the electrostatic adsorption force of the electrostatic field and the compressed air, the production time of the battery can be effectively shortened, and the insulating protective coating has better uniformity, better continuity, better flatness and better smoothness after being formed, thereby effectively improving the production efficiency and yield rate of the battery.

[0088] like Figure 4 As shown, in one embodiment, the electrostatic spraying equipment 10 further includes a paint recovery pool 600 and a recovery pipe 700, wherein the paint recovery pool 600 is arranged directly below the processing fixture 500, and the paint recovery pool 600 is connected to one end of the recovery pipe 700, and the other end of the recovery pipe 700 is connected to the paint pool 100. It can be understood that during the spraying process, part of the insulating paint is not adsorbed on the battery shell and falls on the ground. In order to avoid wasting the insulating paint, the insulating paint can be effectively recovered by arranging the paint recovery pool 600 directly below the processing fixture 500, and the recovered insulating paint is returned to the paint pool 100 through the recovery pipe 700 for recycling, which can effectively improve the utilization rate of the material.

[0089] In one embodiment, the atomizing device is one of an ultrasonic atomizer, a compression atomizer or a mesh atomizer. It is understandable that the ultrasonic atomizer, the compression atomizer or the mesh atomizer can atomize the charged insulating coating and spray the charged insulating coating evenly on the battery housing in the processing fixture. At the same time, under the action of electrostatic force and compressed air, the charged insulating coating can be quickly and evenly adsorbed on the battery housing, so that the insulating protective coating has better uniformity, better continuity, better flatness and better smoothness after forming, thereby effectively improving the production efficiency and yield rate of the battery.

[0090] The present application also provides an insulating protective coating, which is prepared by the method for preparing an insulating protective coating for a battery according to any of the above embodiments;

[0091] The insulating protective coating includes the following components in parts by mass:

[0092] 10 to 80 parts of the first high molecular polymer;

[0093] 10 to 80 parts of the second high molecular weight polymer;

[0094] 5 to 10 parts of inorganic filler.

[0095] In this embodiment, at this ratio, the insulating protective layer composed of the first high molecular polymer and the second high molecular polymer has good electrical insulation performance and good high temperature resistance, and the first high molecular polymer has good adhesion and good dispersibility, and combined with the preparation method of electrostatic spraying, a layer of insulating protective coating with good uniformity, good continuity, good flatness and good smoothness is formed on the surface of the battery, which can effectively improve the yield rate of the battery.

[0096] It should also be noted that the inorganic filler can color the insulating protective coating.

[0097] In one embodiment, the mass fractions of the components of the insulating protective coating are preferably:

[0098] 30 to 50 parts of the first high molecular polymer;

[0099] 40 to 60 parts of the second high molecular polymer;

[0100] 5 to 8 parts of inorganic filler.

[0101] It should be noted that under this mass fraction distribution, each component is dispersed more evenly in the system, thereby ensuring that the insulating protective layer has good insulating properties. At the same time, the surface uniformity, continuity, flatness and smoothness of the insulating protective layer after molding are further improved, further improving the battery yield.

[0102] In one embodiment, the first high molecular polymer includes polyamide, polyimide, polyacrylic acid, polypropylene, polyacrylamide and epoxy resin.

[0103] It should be noted that polyamide can improve the wear resistance, weather resistance and corrosion resistance of the insulating protective layer. Polyimide improves the electrical insulation performance and high temperature resistance of the insulating protective layer. Since polyacrylic acid has a good dispersion effect, each component can be more evenly dispersed under the action of polyacrylic acid. Polypropylene can improve the flexibility of the insulating protective film. Polyacrylamide acts as a flocculant in the system, allowing the insulating coating to form a glue during the preparation process. Epoxy resin has good adhesion and insulation, and can form a uniform and continuous insulating coating under the action of epoxy resin and polyacrylic acid. In this way, under the synergistic effect of each component, the first high molecular polymer makes the insulating protective layer formed by the insulating coating have better uniformity, better continuity and better flatness, and can effectively improve the adhesion between the insulating protective layer and the battery shell, thereby effectively improving the battery yield.

[0104] In one embodiment, the second high molecular polymer includes polyvinylidene fluoride, polytetrafluoroethylene, polyethylene and polypropylene.

[0105] It should be noted that polyvinylidene fluoride not only has good adhesion, but also has good low flammability and electrical insulation properties, that is, polyvinylidene fluoride can not only effectively improve the adhesion between the insulating protective layer and the battery shell, but also improve the electrical insulation and fire resistance of the insulating protective layer. Polytetrafluoroethylene has high lubricity, which makes the insulating protective layer smoother when formed. Polyethylene has good electrical insulation and good corrosion resistance, which effectively improves the electrical insulation and corrosion resistance of the insulating protective layer, and polypropylene can also improve the electrical insulation of the insulating protective layer. In this way, under the synergistic effect of each component, the second polymer can effectively improve the adhesion, electrical insulation and smoothness of the insulating protective layer, thereby effectively improving the yield of the battery.

[0106] In one embodiment, the inorganic filler is a combination of one or more of silicon dioxide, zirconium oxide, aluminum oxide and titanium oxide. It is understood that the inorganic filler can color the insulating protective layer.

[0107] In order to verify the authenticity of the preparation method of the insulating protective coating for batteries of the present application, Figure 5 The schematic diagram of a battery using a conventional coating process to insulate the battery is shown in FIG. Figure 6 A schematic diagram of a battery in which an insulating coating is applied to the battery using the method for preparing the insulating protective coating for the battery of the present application.

[0108] Depend on Figure 5 It can be seen that there are overlapping areas on the film of the battery housing.

[0109] Depend on Figure 6 It can be seen that there is no overlapping area in the insulating protective layer of the battery casing.

[0110] Compared with the prior art, the present invention has at least the following advantages:

[0111] 1. The preparation method of the insulating protective coating for batteries of the present application first cleans the battery, that is, cleans the surface of the battery to remove foreign matter on the surface of the battery, so as to ensure the cleanliness of the surface of the battery. Secondly, the battery is dried to ensure the dryness of the surface of the battery, so as to facilitate the subsequent spraying operation. Then, the battery is electrostatically sprayed with an insulating coating, that is, the insulating coating with a charge is uniformly adsorbed on the battery shell under the action of electrostatic force, so that the problem of bubbles can be effectively avoided. Moreover, during the electrostatic spraying process, only the positions that do not require insulation need to be covered with a template, and there will be no overlapping areas in the remaining areas after electrostatic spraying. Finally, the battery is cured, that is, the insulating coating is cured on the battery shell to form a uniform, continuous, flat and smooth insulating protective coating.

[0112] 2. Compared with the traditional film-laminating process, the preparation method of the insulating protective coating for the battery of the present application utilizes the effect of electrostatic force to enable the insulating coating to be evenly adsorbed on the battery shell, which not only can meet the fitting accuracy of the insulating protective coating, but also can greatly shorten the production time of the battery, thereby effectively improving the production efficiency of the battery.

[0113] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for preparing an insulating protective coating for a battery, characterized in that: The steps include: Clean the battery; Drying the cleaned battery; Electrostatically spraying the dried battery with insulating paint; Curing the battery after spraying so that an insulating protective coating is formed on the battery shell; The specific operation steps of electrostatically spraying the dried battery with the insulating coating are as follows: Performing a heating and fluidizing operation on the insulating coating to obtain a fluid insulating coating; Performing a charging operation on the fluid insulating coating to obtain a charged insulating coating; Performing atomization spraying operation on the charged insulating coating; The heating temperature of the heating fluidization operation is 100°C to 200°C; The specific operation steps of performing the electrification operation on the fluid insulating coating are: Applying voltage to the fluid insulating coating through a high-voltage device to obtain the charged insulating coating; The voltage value is 10kv~110kv; The mass fractions of the components of the insulating protective coating are: 30 to 50 parts of the first high molecular polymer; 40 to 60 parts of the second high molecular polymer; 5~8 parts of inorganic filler; The first high molecular polymer includes polyamide, polyimide, polyacrylic acid, polyacrylate, polyacrylamide and epoxy resin; The second high molecular polymer includes polyvinylidene fluoride, polytetrafluoroethylene, polyethylene and polypropylene.

2. The method for preparing an insulating protective coating for a battery according to claim 1, characterized in that: The specific steps of cleaning the battery are as follows: The battery is cleaned with hot water.

3. The method for preparing an insulating protective coating for a battery according to claim 2, characterized in that: The water temperature of the hot water is 35°C to 50°C.

4. The method for preparing an insulating protective coating for a battery according to claim 1, characterized in that: The specific operation steps of drying the cleaned battery are as follows: The battery is dried using hot air.

5. The method for preparing an insulating protective coating for a battery according to claim 4, characterized in that: The temperature of the hot air is 110°C to 140°C.

6. An insulating protective coating, characterized in that: The insulating protective coating is prepared by the method for preparing the insulating protective coating for the battery according to any one of claims 1 to 5.

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