Overvoltage relaxation of lithium ion secondary batteries after current interruption

Theoretical modelling

Abstract

It is well known that the lithium secondary battery (LiSB) is the most promising power source for electric vehicle (EV), the further development is still needed to assure the life and performance prediction of LiSB. In our former paper1), we reported that the overvoltage relaxation after the current interruption could be expressed by the linear relation to the square root of time for initial stage and the following exponential decay. However, this function was derived for only separator part, and the real battery showed some potential stationary for the initial stage after current interruption, there was no explanation for these phenomena. In this paper, we derived the theoretical functions for the potential relaxation process after the current interruption by applying the transmission line model for LiSB electrodes, and the attributions for these phenomena have been made.