From：CTECHI GROUP Limited Release time：2019-11-06
Overview：Many companies' battery products can achieve normal discharge at low temperatures, but at the same temperature, it is more difficult to achieve normal charging, and even can not be charged.
Why does a lithium battery require more temperature than discharge?
Many companies' battery products can achieve normal discharge at low temperatures, but at the same temperature, it is more difficult to achieve normal charging, and even can not be charged. When Li+ is embedded in graphite material, it must first be desolvated, this process will consume a certain amount of energy. It hinders the diffusion of Li+ into the graphite; on the contrary, Li+ has a solvation process when it takes out the graphite material into the solution, while solvation does not consume energy, and Li+ can quickly take out graphite. Therefore, the charge acceptance of the graphite material is significantly inferior to the discharge acceptance capability.
Lithium battery charging has certain risks in low temperature environments. Because the kinetics of the graphite anode deteriorates with the decrease of temperature, the electrochemical polarization of the anode is obviously intensified during the charging process, and the precipitated metal lithium easily forms lithium dendrites, which break through the separator and cause short circuit between the positive and negative electrodes. .
Try to avoid lithium-ion batteries charging at low temperatures. When the battery must be charged at a low temperature, it is necessary to select a small current (ie, slow charge) to charge the lithium ion battery, and fully charge the lithium ion battery after charging, thereby ensuring that the lithium metal precipitated by the negative electrode can react with the graphite. , re-embedded into the graphite negative electrode.