Mixing (positive and negative active materials + conductive agent + binder + dispersant) - coating - rolling - cutting - tab welding - winding (or gasket) - adhesive paper - entering the battery shell - Welding - Sealing - Formation, etc.; Basically, the battery production process in the entire industry is similar. The main difference is the difference in equipment or different battery products. For example, soft-pack lithium battery packs generally have lamination, cylindrical winding, square winding and lamination coexist. ; Causes the battery core to be different during the winding process; the most important and core technology is mixing and coating, as well as the final formation.

　　The production process of lithium battery packs is relatively complex. The main production process mainly covers the stirring and coating stage of electrode production, the winding and liquid injection stage of cell synthesis, and the packaging and testing stage of chemical packaging. The value ratio is about (35~40 %): (30~35)%: (30~35)%. According to Coating Online, the differences mainly come from different equipment suppliers, differences in the proportion of imported/domestic products, etc. The process flow is basically the same, and the value ratio is deviated but generally consistent with this ratio.

　　The lithium battery equipment corresponding to the front-end process of lithium battery pack production mainly includes vacuum mixers, coating machines, roller presses, etc.; the middle-stage process mainly includes die-cutting machines, winding machines, lamination machines, liquid injection machines, etc.; the back-end process includes Formation machines, volumetric testing equipment, process warehousing and logistics automation, etc. In addition, the production of battery packs also requires Pack automation equipment.

　　In the lithium battery manufacturing process, the middle process is mainly to complete the forming of the battery. The main process includes sheeting, pole piece winding, die cutting, cell winding and lamination forming, etc. It is currently a fierce competition among domestic equipment manufacturers. A field that accounts for about 30% of the value of lithium battery pack production lines.

　　Lithium battery back-end process flow: volume separation and formation is the core link

　　The back-end production process of lithium battery packs mainly consists of four processes: volume separation, formation, testing, and packaging and warehousing, accounting for approximately 35% of the value of the production line. Formation and volume separation are the most important links in the back-end process, and the formed batteries are activated and tested. Since the battery has a long charge and discharge test cycle, the value of the equipment is the highest. The main function of the formation process is to charge and activate the cells after liquid injection and encapsulation. The capacity dividing process is to test the battery capacity and other electrical performance parameters and classify them after the battery is activated. The formation and volume separation are performed by the formation machine and the volume separation machine respectively, usually by an automated volume separation and conversion system.

　　The production process flow of lithium battery soft pack cells:

　　Soft-packed lithium batteries use thermal packaging, while metal-cased batteries generally use welding (laser welding). The reason why soft-packed batteries can be thermally sealed is that they use aluminum-plastic packaging film.

　　The first step - preparation of electrode slurry

　　It mainly mixes electrode active materials, binders, solvents, etc. together, and then stirs and disperses them thoroughly to form a slurry;

　　The second step - coating

　　Apply the slurry prepared in the first step evenly to the current collector (aluminum foil or copper foil, etc.) with a specified thickness, and dry the solvent;

　　Step 3 - Pole piece punching

　　Cut the pole piece made in the previous step into the specified size and shape;

　　Step 4 - Lamination

　　Assemble the positive and negative electrode sheets and separator together, and after completing the glue application, form the electrode core;

　　Step 5--Assemble the soft pack battery

　　Put the pole core produced in the previous step into the aluminum-plastic film that has been punched, and complete the top seal, side seal, etc. (leave a mouth for liquid injection) to form a soft-pack battery without liquid injection;

　　Step 6 - Injection

　　Inject the specified amount of electrolyte into the soft-packed battery core;

　　Step 7--Battery sealing

　　The gas inside the cell is extracted and sealed in a vacuum environment.

　　Advantages of soft pack lithium batteries:

　　1. Good safety performance. The soft-packed lithium battery pack is structurally packaged with aluminum-plastic film. In the event of a safety hazard, the soft-packed battery will only bulge and crack at most, unlike steel-shelled aluminum-shelled batteries. explode.

　　2. Light weight. Soft-pack lithium batteries are 40% lighter than steel-case lithium batteries of the same capacity and 20% lighter than aluminum-case batteries.

　　3. Large capacity. The capacity of lithium battery pack soft pack is 10-15% higher than that of steel-shell batteries of the same size, and 5-10% higher than that of aluminum-shell batteries.

　　4. Small internal resistance. The internal resistance of soft-pack batteries is smaller than that of lithium batteries. At present, the minimum internal resistance of domestic soft-pack battery cells can be less than 35mΩ, which greatly reduces the self-consumption of the battery.

　　5. Flexible design, the shape of the soft-pack lithium battery can be customized according to customer needs, and new cell models can be developed.

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