What are the disadvantages of graphite as a negative electrode material for lithium batteries
Graphite has a six-membered ring carbon network layered structure, the carbon-carbon is SP2 hybridized, and the layers are connected by molecular force. Graphite lithium batteries have the advantages of low cost, high crystallinity, mature purification, crushing, and classification technologies, low charge and discharge voltage platform, and high theoretical specific capacity. Lithium battery anode material.jpg Disadvantages of graphite as a lithium battery anode material 1. Poor solubility in the electrolyte solution and high selectivity. The intercalation compound formed by lithium and carbon during the first charge and discharge process is very unstable in the electrolyte. It easily reacts with the electrolyte. A small part of the product is dissolved in the electrolyte, and the other part forms an SEI film on the surface of the negative electrode and the electrolyte. The SEI membrane can prevent the electrolyte molecules from continuously being inserted into the graphite negative electrode, which can greatly increase the service life of the battery. 2. The high-current discharge performance is poor. The SEI film formed on the surface of the graphite negative electrode is uneven and thick, which will cause the Li+ to pass through the SEI film for a long time, and the graphite itself has high orientation. Li+ can only be inserted perpendicular to the C axis of the graphite end face , The high current discharge performance is not ideal. 3. Due to its own crystal structure and the limitation of crystal lattice and crystal packet parameters, the number of inserted Li+ is limited, which determines its capacity. Disclaimer: Some pictures and content of the articles published on this site are from the Internet. If there is any infringement, please contact to delete.