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

A nonaqueous-electrolyte battery comprising:

• a positive electrode containing a lithium composite oxide;
• a negative electrode disposed opposite to the positive electrode and containing a mixture of a non-carbon material to which lithium is adapted to be doped/dedoped and a carbon material;
• and
• a nonaqueous electrolyte disposed between the positive electrode and the negative electrode, wherein
• an average particle size of the non-carbon material is defined as RM and an average particle size of the carbon material is defined as RC such that a ratio RM/RC is not higher than one,
• wherein a weight of the non-carbon material is defined as WM and a weight of the carbon is defined as WC such that a ratio WM/WC is not higher than one,
• wherein the non-carbon material constitutes an alloy expressed by a general formula LixMM′ in association with lithium, where each of M and M′ is an element except for Li and C and where a relationship that x≧0.01 is satisfied, and
• wherein at least one of M and M′ is an element selected from a group consisting of Si, Sn, Al and In.

A nonaqueous-electrolyte battery comprising:

• a positive electrode containing a lithium composite oxide;
• a negative electrode disposed opposite to the positive electrode and containing a mixture of a silicon compound and a carbon material;
• and
• a nonaqueous electrolyte disposed between the positive electrode and the negative electrode, wherein
• an average particle size of the silicon material is defined as RSi and an average particle size of the carbon material is defined as RC such that a ratio RSi/RC is not higher than one.