What factors restrict the low temperature performance of lithium batteries?

Factors restricting the low-temperature performance of lithium batteries ◆Positive structure The three-dimensional structure of the positive electrode material restricts the diffusion rate of lithium ions, and the effect is particularly obvious at low temperatures. The cathode materials of lithium batteries include commercial lithium iron phosphate, nickel cobalt manganese ternary materials, lithium manganese oxide, lithium cobalt oxide, etc., as well as high-voltage cathode materials in the development stage such as lithium nickel manganese oxide, lithium iron manganese phosphate, Lithium vanadium phosphate, etc. Different cathode materials have different three-dimensional structures. The current cathode materials used as power lithium-ion batteries for electric vehicles are mainly lithium iron phosphate, nickel cobalt manganese ternary materials and lithium manganate. ◆High melting point solvents Due to the presence of high melting point solvents in the electrolyte mixed solvent, the viscosity of the lithium battery electrolyte increases in a low temperature environment. When the temperature is too low, the electrolyte solidification will occur, resulting in a decrease in the transmission rate of lithium ions in the electrolyte. ◆Lithium ion diffusion rate The diffusion rate of lithium ions in the graphite anode is reduced in a low temperature environment. Xiang Yu systematically studied the influence of graphite anode on the low-temperature discharge performance of lithium batteries, and proposed that the increase in charge transfer resistance of lithium batteries in low-temperature environments, resulting in a decrease in the diffusion rate of lithium ions in the graphite anode, is an important reason for the low-temperature performance of lithium batteries. ◆Under the low temperature environment of the SEI film, the SEI film of the negative electrode of the lithium battery becomes thicker, and the impedance of the SEI film increases, which causes the conduction rate of lithium ions in the SEI film to decrease. Eventually, the lithium battery is charged and discharged in a low temperature environment to form polarization and reduce the charge and discharge efficiency. 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 article: How to maintain the lithium battery?