Introduction to the processing flow of 26650 lithium-ion batteries.
The production and processing flow and control of lithium-ion batteries: raw materials → raw material inspection → raw material pretreatment → batching → batching inspection → vacuum induction melting → rapid cooling ingot casting → semi-finished product inspection → heat treatment → coarse crushing → powder milling → screening → post-treatment → vacuum or nitrogen filling packaging → finished product inspection → product.
Smelting
1. The process requires the material supplier to provide a material list, and the QC department also needs to conduct testing. If the composition and impurity content meet the process requirements, they will be stored for future use.
2. The important aspect of raw material pretreatment is to remove pollutants and oxide layers from the surface of raw materials, ensuring their cleanliness.
3. The ingredients should be supplemented with certain volatile elements such as rare earths and manganese according to the prescribed indicators based on different situations.
4. Vacuum induction melting requires filling argon gas at a vacuum degree of 0.1Pa, melting each component metal into an alloy at a high temperature of 1300 ℃, and rapidly cooling the ingot to obtain an alloy with refined grain size and uniform structure.
Semi finished product
1. Appearance: The appearance of the alloy should have a metallic luster, no obvious oxidation discoloration, and the alloy structure should be uniform and dense, without looseness or impurities;
2. Chemical composition: The chemical composition of the alloy should match the design composition;
3. Electrochemical capacity: It should meet the company's standard requirements, otherwise it cannot be lowered.
3、 Heat treatment: A vacuum heat treatment furnace is used, which is evacuated and then filled with argon gas for protection. The heat treatment process is important for homogenizing and stabilizing the product (eliminating internal stress), ensuring a flat platform pressure, good uniformity, and good cycle life characteristics of the alloy. Focus on ensuring temperature and vacuum degree, and conduct oxygen content measurement.
4、 The entire process of coarse crushing, powder production, and packaging of the alloy is fully enclosed under argon protection to ensure that the oxygen content of the alloy is very low.
