Tomographical analysis of electrochemical lithiation and delithiation of LiNi 0.6 Co 0.2 Mn 0.2 O 2 cathodes in all-solid-state batteries

Abstract

We demonstrated the use of three-dimensional (3D) atom-probe tomography (APT) for analyzing the electrochemical lithiation/delithiation in the composite cathodes of all-solid-state batteries (ASSBs). 3D APT provides direct determination of the Li-ion contents, having difficult by X-ray excitation. Compared with various cathodes, they showed a significant variation in the Li-ion concentration during lithiation/delithiation because of the poor solid-to-solid interfaces, which is an inherent problem in ASSBs. In addition, the loss of transition-metal content was quantitatively verified. We have confirmed that our APT can be effectively applied to ASSB systems and it would be provide a deeper understanding of electrochemistry in ASSBs.