What is the composition of lithium batteries? What is the role of the chemical composition of lithium batteries? As the power source of future electric vehicles and energy storage, lithium batteries need to be formed and divided into cells during the production process to ensure the quality and quality of the final power supply product.

The lithium battery has no power when assembly is completed and must be charged to activate. The first charge is called 'formation' and is used to activate the active materials in the battery body. Formation, also called 'activation', is a very complex process, and it is also an important process that affects battery performance, because during the first charging process of the battery, it is inevitable to form at the interface between the carbon negative electrode and the electrolyte. The thin passivation layer covering the surface of the carbon electrode is called the solid electrolyte interface film or SEI film.

The capacity of the battery is determined by charging and discharging the battery and detecting the discharge capacity when the capacity is fully charged. Only batteries whose tested capacity meets or exceeds the design capacity are qualified. This process of selecting qualified batteries through capacity testing is called capacity classification.

2. The role of formation and  classification
The formation, volume fractionation and detection system are the most critical links in the back-end process. The chemical composition of lithium battery cells is achieved by charging and discharging to activate the active material of the battery cells, which is an energy conversion process. The composition and capacity principle of lithium battery cells is relatively complex, but it is also an important process that affects battery performance. The power connector serves as a connection switch between the battery and the outside and also affects the performance of the battery. High-quality battery terminals allow lithium batteries to be used effectively.

Formation is just a charging process, and there is no need to discharge the battery core. Therefore, a separate charger can be used during formation, so the charger is often called a forming machine or a forming cabinet. Although formation does not require discharge, the formation process of some cells requires more than one charge. The capacity dividing process immediately after formation requires charging and then discharging the cells. After formation and charging, the cells must also be discharged. This technological need has also led many battery manufacturers to directly use charge and discharge machines with charging and discharging functions for formation.