US Patent 9871247 Germanium-containing active material for anodes for lithium-ion devices

Active materials for anodes for lithium ion devices are disclosed. An active may comprise germanium nano-particles having a particle size of 20 to 100 nm, wherein the weight percentage of the germanium is between 72 to 96 weight % of the total weight of the active material; boron carbide nano-particles having a particle size of 20 to 100 nm, wherein the weight percentage of boron in the active material is between 3 to 6 weight % of the total weight of the active material; and tungsten carbide nano-particles having a particle size of 20 to 60 nm, wherein the weight percentage of tungsten in the active material is between 6 to 25 weight % of the total weight of the active material.