| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a nonaqueous electrolyte secondary battery low in cost and excellent in cycle characteristics. <P>SOLUTION: Natural graphite is used as a negative electrode active material, and a lithium cobalt composite oxide containing 10-100 ppm of iron and/or a lithium nickel cobalt manganese composite oxide containing 10-100 ppm of iron are used as a positive electrode active material. The lithium cobalt composite oxide is expressed: Li<SB POS="POST">a</SB>Co<SB POS="POST">1-x-y</SB>Ti<SB POS="POST">x</SB>M<SB POS="POST">y</SB>O<SB POS="POST">2</SB>(where 0<a≥1.1, 0.0001≥x≥0.005, 0.001≥y≥0.03, and M is at least one kind of Mg and Al). The lithium nickel cobalt manganese composite oxide is expressed: Li<SB POS="POST">b</SB>Ni<SB POS="POST">s</SB>Co<SB POS="POST">t</SB>Mn<SB POS="POST">u</SB>O<SB POS="POST">2</SB>(where 0<b≥1.1, 0.1≥s≥0.5, 0<t≥0.8, 0.1≥u≥0.5, and s+t+u=1). <P>COPYRIGHT: (C)2012,JPO&INPIT |
