Optimal charge current of lithium ion battery

It is an essential issue that fast charging of lithium ion battery which is restricted by lithium deposition. The aim of this research is to provide an optimal charge current of lithium ion battery, by which the theoretically fastest charging speed without lithium deposition is able to be reached. In other words, a maximal acceptable charge current of lithium ion battery is proposed. The expression of the charge curve is derived mathematically according to the lithium deposition criterion and validated by an electrochemical model. The charge current is found highly related with the anode equilibrium potential Un, as well as the charge transfer resistance Rct which is a critical parameter. Lower Rct can accommodate higher acceptable charge current amplitude, indicating that better charge capability of the battery. For real applications, the charge current can be easily derived from this method and directly used to charge the lithium ion battery in electric vehicles.