Preparation and properties nanomaterials for all-solid-state li-ion battery via a mechanochemical route

Abstract

A short overview is given on the rationalization of preparative processes of complex oxide nanoparticles for an all-solid-state Li-ion battery (SLIB). After a brief introduction associated with mechanochemical effects as a background, merits of combining mechanical activation and subsequent chemical treatments for the synthesis of complex oxide nanoparticles are emphasized. Mechanical stressing on the stoichiometric mixture of all the ingredients at an appropriate stage significantly reduces the subsequent calcination temperature. It is necessary for attaining high crystallinity and phase purity, while suppressing grain growth. A precursor with preformed embryos or nuclei is appropriate for subsequent low temperature solid-state synthesis. This is realized by careful choice of the starting ingredients and sparing mechanical stressing, usually exerted by a grinding mill. The procedure leads to complex oxide materials with high crystallinity and small particle size, simultaneously. Such properties are suitable for the application to electronic devices and SLIB. The entire techniques are associated with an extended concept of mechanochemistry. Case studies were centered on the garnet type cubic Li7La3Zr2O12 (c-LLZO), one of the most promising solid electrolytes for SLIB. Some notices for non-sintered c-LLZO film are given as a core of SLIB.