Soft pack lithium battery production process and process flow

　　Each of the three layers has its own function. First of all, the nylon layer ensures the shape of the aluminum-plastic film and ensures that the film will not be deformed before being manufactured into a lithium ion battery.

　　The Al layer is composed of a layer of metallic Al, and its function is to prevent the penetration of water. Lithium-ion batteries are very afraid of water. Generally, the water content of the pole pieces is required to be at the PPM level, so the packaging film must be able to block the infiltration of moisture. Nylon is not waterproof and cannot provide protection. The metal Al will react with oxygen in the air to form a dense oxide film at room temperature, which prevents water vapor from penetrating and protects the inside of the cell. The Al layer also provides the plasticity of punching pits when the aluminum plastic film is formed. Please refer to point 3 for details.

　　PP is the abbreviation of polypropylene. The characteristic of this material is that it will melt at a temperature of more than one hundred degrees Celsius, and it is viscous. Therefore, the thermal packaging of the battery mainly relies on the PP layer being melted and bonded together under the action of the heating of the head, and then the head is removed, and the temperature is cooled to solidify and bond.

　　Aluminum plastic film looks very simple. In practice, how to evenly and firmly combine the three layers of materials is not so easy. It is a pity that the good quality aluminum-plastic film is basically imported from Japan, and the domestic ones are not available, but the quality needs to be improved.

　　aluminum plastic film forming process

　　The soft-packed batteries can be designed into different sizes according to the needs of customers. After the external dimensions are designed, the corresponding molds need to be opened to form the aluminum-plastic film. The molding process is also called a punching hole (in fact, I think it should be a "punch hole", but everyone writes it like that). As the name suggests, it is to punch out a mold that can be mounted on the aluminum-plastic film under the condition of heating. Core pit

　　Soft-pack batteries are actually batteries that use aluminum-plastic packaging film as the packaging material. Relatively speaking, the packaging of lithium-ion batteries is divided into two categories, one is soft-packed batteries, and the other is metal shell batteries. Metal shell batteries also include steel shells and aluminum shells, etc. In recent years, some batteries that use plastic shells due to special needs can also be classified as this type.

　　The difference between the two is not only the case material, but also the different packaging method. Soft-packed cells are thermally packaged, while metal shell cells are generally welded (laser welding). The reason why soft-pack batteries can be thermally packaged is that they use aluminum-plastic packaging film.

　　1, soft pack battery

　　The so-called soft-pack batteries are actually batteries that use aluminum-plastic packaging film as the packaging material. Relatively speaking, the packaging of lithium-ion batteries is divided into two categories, one is soft-packed batteries, and the other is metal shell batteries. Metal shell batteries also include steel shells and aluminum shells, etc. In recent years, some batteries that use plastic shells due to special needs can also be classified as this type.

　　The difference between the two is not only the case material, but also the different packaging method. Soft-packed cells are thermally packaged, while metal shell cells are generally welded (laser welding). The reason why soft-pack batteries can be thermally packaged is that they use aluminum-plastic packaging film.

　　The constitution of aluminum-plastic packaging film (abbreviated as aluminum-plastic film) is shown in the figure, its cross-section has three layers: nylon layer, Al layer and PP layer.

　　Each of the three layers has its own function. First of all, the nylon layer ensures the shape of the aluminum-plastic film and ensures that the film will not be deformed before being manufactured into a lithium ion battery.

　　The Al layer is composed of a layer of metallic Al, and its function is to prevent the penetration of water. Lithium-ion batteries are very afraid of water. Generally, the water content of the pole pieces is required to be at the PPM level, so the packaging film must be able to block the infiltration of moisture. Nylon is not waterproof and cannot provide protection. The metal Al will react with oxygen in the air to form a dense oxide film at room temperature, which prevents water vapor from penetrating and protects the inside of the cell. The Al layer also provides the plasticity of punching pits when the aluminum plastic film is formed. Please refer to point 3 for details.

　　PP is the abbreviation of polypropylene. The characteristic of this material is that it will melt at a temperature of more than one hundred degrees Celsius, and it is viscous. Therefore, the thermal packaging of the battery mainly relies on the PP layer being melted and bonded together under the action of the heating of the head, and then the head is removed, and the temperature is cooled to solidify and bond.

　　Aluminum plastic film looks very simple. In practice, how to evenly and firmly combine the three layers of materials is not so easy. It is a pity that the good quality aluminum-plastic film is basically imported from Japan, and the domestic ones are not available, but the quality needs to be improved.

　　3, aluminum plastic film forming process

　　The soft-packed batteries can be designed into different sizes according to the needs of customers. After the external dimensions are designed, the corresponding molds need to be opened to form the aluminum-plastic film. The molding process is also called a punching hole (in fact, I think it should be a "punch hole", but everyone writes it like that). As the name suggests, it is to punch out a mold that can be mounted on the aluminum-plastic film under the condition of heating. The pit of the core,

　　The constitution of aluminum-plastic packaging film (abbreviated as aluminum-plastic film) is shown in the figure, its cross-section has three layers: nylon layer, Al layer and PP layer.

　　Each of the three layers has its own function. First of all, the nylon layer ensures the shape of the aluminum-plastic film and ensures that the film will not be deformed before being manufactured into a lithium ion battery.

　　The Al layer is composed of a layer of metallic Al, and its function is to prevent the penetration of water. Lithium-ion batteries are very afraid of water. Generally, the water content of the pole pieces is required to be at the PPM level, so the packaging film must be able to block the infiltration of moisture. Nylon is not waterproof and cannot provide protection. The metal Al will react with oxygen in the air to form a dense oxide film at room temperature, which prevents water vapor from penetrating and protects the inside of the cell. The Al layer also provides the plasticity of punching pits when the aluminum plastic film is formed. Please refer to point 3 for details.

　　PP is the abbreviation of polypropylene. The characteristic of this material is that it will melt at a temperature of more than one hundred degrees Celsius, and it is viscous. Therefore, the thermal packaging of the battery mainly relies on the PP layer being melted and bonded together under the action of the heating of the head, and then the head is removed, and the temperature is cooled to solidify and bond.

　　Aluminum plastic film looks very simple. In practice, how to evenly and firmly combine the three layers of materials is not so easy. It is a pity that the good quality aluminum-plastic film is basically imported from Japan, and the domestic ones are not available, but the quality needs to be improved.

　　aluminum plastic film forming process

　　The soft-packed batteries can be designed into different sizes according to the needs of customers. After the external dimensions are designed, the corresponding molds need to be opened to form the aluminum-plastic film. The molding process is also called a punching hole (in fact, I think it should be a "punch hole", but everyone writes it like that). As the name suggests, it is to punch out a mold that can be mounted on the aluminum-plastic film under the condition of heating. Core pit