| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide silicon oxide used as an anode active material for a lithium ion secondary battery having stable initial efficiency and stable cycle characteristics, and also to provide an anode material for a lithium ion secondary battery. <P>SOLUTION: In the powdery silicon oxide used for an anode active material for a lithium ion secondary battery and expressed in SiO<SB>x</SB>, when the silicon oxide is measured by using an X-ray diffraction system equipped with an enclosed type light source as a light source and a high speed detector as a detector, a halo is detected at 20°≤2θ≤40°, a peak is detected at the strongest line position of quartz, and a height P1 of the halo and a peak height P2 at the strongest line position of the quartz satisfies P2/P1≤0.05. It is preferable that x of the SiO<SB>x</SB>is 0.7<x<1.5. The anode material for a lithium ion secondary battery includes silicon oxide of 20 mass% or more as an anode active material. <P>COPYRIGHT: (C)2011,JPO&INPIT |
