Tin Networked Electrode Providing Enhanced Volumetric Capacity and Pressureless Operation for All-Solid-State Li-Ion Batteries

Abstract

Pure tin (Sn) metal nano-powder is investigated as a high capacity negative electrode for rechargeable all-solid-state Li-ion batteries. Sn is used to form a fully dense network intertwining with solid electrolyte negating necessary conductive additive. Galvanostatic cycling of the Sn composite electrode delivers a reversible capacity 800 mAh g−1 of Sn with a constant coulombic efficiency over 99.2%. We report on the effect of pressure and rate upon the delithiation mechanics, drawing correlations between Sn volume increase factors and stress accumulation over the course of Sn-Li phase transformations. Due to the fabricated electrode microstructure, we are able to operate the cell at ambient pressure conditions – the next step toward commercialization of the solid-state battery. We believe that this initial work provides new opportunities to study the electrochemical expansion of Sn with the inclusion of rigid electrolyte particles.