| 摘要 |
PROBLEM TO BE SOLVED: To provide a sufficient strength of being never reduced in the impact resistance or charge and discharge cycle durability of an electrode by using a sintered body obtained by molding silicon powder and a fibrous reinforcing material into a prescribed form followed by thermally treating in non-oxidizing atmosphere as a battery negative electrode material. SOLUTION: Silicon powder used for a nonaqueous secondary battery negative electrode desirably has a particle size of about 0.1-10 μm, and its purity is set to 90% or more. In order to provide a high capacity, the content of silicon is set to 30-90 wt.% in the sintered body, desirably, 50-90 wt.%. In order to impart sufficient mechanical strength and conductivity to the negative electrode, the content rate of the fibrous reinforcing material is set to 1-70 wt.%, desirably, 5-30 wt.%. A mixed powder consisting of silicon powder and the fibrous reinforcing material is pressure molded by a pressing machine and thermally treated under non-oxidizing atmosphere in the temperature range of 600-1400 deg.C to provide a negative electrode sintered body. The sintered body desirably consists of a porous body having a porosity of 15-60%. |
