Ge/GeO 2 /multi-layer graphite nanocomposites as anode materials for lithium-ion batteries

Germanium (Ge) has been considered as a promising material applied in lithium-ion batteries due to its unique properties, e.g. high capacity, fast lithium-ion diffusivity, and high electrical conductivity. In this work, Ge/GeO 2 /multi-layer graphite (Ge/GeO 2 /MLG) nanocomposites have been synthesized using a solution process from graphite oxide and GeO 2 precursors. The electrochemical performances of the prepared Ge/GeO 2 /MLG nanocomposites were then investigated. The experimental results indicated that in the first cycle, the electrode delivered discharge and charge capacities of 2046 and 1146 mA h g −1 , giving the Coulombic efficiency of 56.0%. After 50 cycles, the electrode capacity was still maintained at 1008 mA h g −1 at 100 mA g −1 in the potential range from 0.01 to 1.5 V, and it reached high capacities of 790 and 700 mA h g −1 at the high rates of 1 and 2 A g −1 .