Material for negative electrode and nonaqueous-electrolyte battery incorporating the same

摘要

A material for a negative electrode capable of preventing change in the volume of an active material occurring when lithium is doped/dedoped to improve resistance against cycle operations. A material for a negative electrode contains a mixture of a non-carbon material and a carbon material, wherein when an assumption is made that the average particle size of the non-carbon material is RM and the average particle size of the carbon material is RC, the ratio RM/RC is not higher than one, and when an assumption is made that the weight of the non-carbon material is WM and the weight of the carbon is WC, the ratio WM/WC is not higher than one or a mixture of a silicon compound and a carbon material, wherein when an assumption is made that the average particle size of the silicon compound is RSi and the average particle size of the carbon material is RC, the ratio RSi/RC is not higher than one.