Mechanism and Solution of Overcharge Effect in Lithium-Sulfur Batteries.

Abstract

Increasing the sulfur cathode load is an important method for promoting the commercialization of lithium-sulfur batteries. However, there is a common problem of overcharging in high-loading experiments, which is rarely reported. In this work,it isbelieved that an insulating layer of S8 forms on the current collector surface, hindering electron exchange with polysulfides. Continuous external current input during layer formation can cause irreversible electrode changes and overcharging. The general solution is to provide nucleation centers with adsorption sites to promote the 3D growth of the insulated S8 , thus avoiding overcharging. In this work, a solution isproposed by providing nucleation centers by gallium nitrate, by regulating the 3D growth of S8 away from the surface of the current collector to avoid overcharging and by improving battery performance.