Germanium based glass modified by graphene as anode material with high capacity for lithium-ion batteries

Abstract

The performance of a lithium-ion battery (LIB) is largely contingent upon its anode material. At present, germanium-based anode materials are of interest due to their high theoretical capacity, but there are fewer studies on germanium-based glass anode materials. In this work, graphene mixed germanium-based glass composite material was fabricated utilizing the ball-milling technique. The addition of graphene greatly reduces the charge transfer resistance of the germanium-based glass anode during cycling. Meanwhile, the composite anode exhibited a high specific capacity of 1101.5 mAh g^-1 during the first discharge cycle, and the discharge/charge specific capacity was still as high as 1108.2/1098.6 mAh g^-1 after 450 cycles at a current density of 500 mA g^-1. Moreover, at a high current of 2 A g^-1, the composite anode still maintains a high discharge specific capacity of 437.2 mAh g^-1, and there is no obvious swelling on the surface, showing excellent stability. It is hoped that the current research endeavor may offer a fresh direction for future studies aimed at optimizing germanium-based glass anode materials.