NONAQUEOUS SECONDARY BATTERY

PURPOSE: To provide a nonaqueous secondary battery having safety and high capacity and voltage by making the negative electrode material of a nonaqueous secondary battery have boride. CONSTITUTION: In a nonaqueous secondary battery composed of a positive electrode active material, negative electrode material, and a nonaqueous electrolyte, boride is to be included as the negative electrode material. This boride is to preferably contain a compound expressed in a general formula: SiBn (n=3.2-6.6) and other than that, alkaline metal, transition metal, and Al, etc.. can be included by 0-30mole% degree. The electrolyte is preferable wherein lithium salt is melted in a solvent such as ethylene carbonate. The positive electrode active material is preferable to include Lix MO2 (x=0.05-l.2, M: Co, Ni, Mn, and Fe) and/or a compound (Co, Ni, Mn, Fe, and V) having the main body of spinel structure.