High-resolution crystal structure analysis with SPring-8 synchrotron radiation for expansion/contraction evaluations among LIB cathode active materials

Abstract

One of the factors for lithium-ion battery degradation is the disruption of electron paths inside electrodes, due to the expansion and contraction of the active material caused by charging and discharging. High-resolution Crystal Structure Analysis using SPring-8 synchrotron radiation has clarified the relationship between the state of charge (S.O.C.) and the expansion and contraction of the active material. As a result, it was found that the expansion and contraction of the lithium-rich ternary active material (NMC) is not monotonous with respect to the S.O.C.s.