| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a lithium ion battery which is superior in safety, along with being a large-capacity and high-output battery. <P>SOLUTION: In a lithium ion secondary battery, a spinel lithium manganese composite oxide is used for the positive-electrode active material, and amorphous carbon is used for the negative-electrode active material. In a positive-electrode mixture, a predetermined quantity of Fe-Cu alloy powder is intentionally made contained. A separator is made of polyethylene and has a thickness of 40μm. By dividing the alloy powder which depends according to the particle size, the ratio a / b is made 0.75 or larger, when the diameter size of the alloy powder is represented by (a), and the thickness of the separator is represented by b. The alloy powder desorbs or is eluted from the positive-electrode mixture by being overcharged, deposits as dendrites on the negative electrode, and penetrates the separator. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
