What problems are encountered in the production of lithium batteries

1. Material dispersion problem Pulping is one of the most critical processes in the battery processing process. Its core task is to evenly mix the active materials, conductive agents, binders and other materials to make the material performance better. To mix well, it must first be able to disperse. As the particles decrease, the corresponding specific surface area increases, so the surface energy increases, and the tendency of particles to polymerize increases. The greater the energy required to overcome the surface energy dispersion. At present, mechanical stirring is commonly used, and the energy distribution of mechanical stirring is uneven. Only in a certain area, the shear strength is high enough and the energy is high enough to separate the aggregated particles. 2. Difficulty in drying. Because lithium iron phosphate has a large surface area and a large amount of binder, the amount of solvent required when preparing the slurry is also large, and it is more difficult to dry after coating. How to control the volatilization rate of solvents is a problem worthy of attention. High temperature, large air volume, and fast drying speed will cause large voids. At the same time, it may drive the migration of colloids, resulting in uneven distribution of materials in the coating. If colloids are concentrated on the surface, it will hinder the conduction of charged particles , Increase impedance. The temperature is low, the air volume is low, the solvent escapes slowly, the drying time is long, and the output is low. 3. Poor flexibility. At present, when the lithium pole piece is produced, it is generally felt that the pole piece is hard and brittle. It may not have a small impact on the laminate, but it is very unfavorable when it is wound. The flexibility of the pole piece is not good, it is easy to fall off and break when winding and bending, resulting in short-circuit and other defects. The mechanism explanation for this is not clear, but it is speculated that the particles are small and the elastic space of the coating is small. Reducing the compaction density can improve, but in this way the volumetric energy density will also be reduced. Originally, the compaction density of lithium iron phosphate is relatively low, and reducing the compaction density is a must. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous: Will frequent fast charging damage the battery life?