Battery products of many enterprises can achieve normal discharge at low temperature, but at the same temperature, to achieve normal charging is more difficult, or even can not be charged, when Li+ embedded graphite material, the first to desolvation, this process will consume a certain amount of energy, hinder the diffusion of Li+ to the graphite; On the contrary, there will be a solvation process when Li+ is removed from graphite material into solution, and the solvation does not consume energy, so Li+ can be quickly removed from graphite. Therefore, the charge acceptance ability of graphite material is obviously inferior to the discharge acceptance ability.
In low temperature environment, lithium battery charging has certain risks. Because with the decrease of temperature, the dynamic characteristics of graphite anode progress to become worse, during the charging process, the electrochemical polarization of the cathode is significantly intensified, the precipitated lithium metal is easy to form lithium dendrite, through the membrane and lead to short circuit of positive and negative poles.
Try to avoid charging lithium-ion batteries at low temperatures. When the battery must be charged at low temperature, it is necessary to choose a small current (that is, slow charging) to charge the lithium ion battery as far as possible, and fully use the lithium ion battery after charging, so that the metal lithium precipitated out of the negative electrode can react with graphite, re-embedded into the graphite negative electrode inside.
Industry enterprises and scientific research institutions to explore and solve the problem of low temperature resistance of batteries, mostly focus on the improvement of the existing anode and anode materials process, and by raising the local ambient temperature of batteries to create conditions for the battery to work at low temperature. With the further development of technology, lithium batteries in low temperature environment will have a further breakthrough.
