| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a pretreatment method capable of improving cycle characteristics within a short time in a lithium ion secondary battery using a solid solution positive electrode active material, and a usage method of a lithium ion secondary battery followed by the pretreatment. <P>SOLUTION: In a lithium ion secondary battery, a positive electrode active material is used, the positive electrode active material being represented by a compositional formula: [Li<SB POS="POST">1.5</SB>][Li<SB POS="POST">0.5(1-x)</SB>Mn<SB POS="POST">1-x</SB>M<SB POS="POST">1.5x</SB>]O<SB POS="POST">3</SB>(in the formula, x satisfies 0.1≤x≤0.325, and M is represented as NiαCoβMnγ where 0≤α≤0.5, 0≤β≤0.33 and 0≤γ≤0.5 are satisfied). In a pretreatment method of the lithium ion secondary battery, an upper limit voltage during charging and a lower limit voltage during discharging are controlled at a constant potential in a voltage range of 4.0 V or higher and less than 4.9 V, and 2.0 V or higher and less than 3.5 V, relative to a Li reference electrode, respectively. <P>COPYRIGHT: (C)2012,JPO&INPIT |
