Silicon oxide and negative electrode material for lithium-ion secondary battery

摘要

A silicon oxide for use as a negative electrode active material of a lithium-ion secondary battery is characterized by: a g-value measured by an ESR spectrometer is in the range of not less than 2.0020 to not more than 2.0050; and given that A, B, and C are the area intensities of peaks near 420 cm−1, 490 cm−1 and 520 cm−1 respectively in a Raman spectrum measured by a Raman spectroscopy, A/B is not less than 0.5 and C/B is not more than 2. The lithium-ion secondary battery has excellent cycle characteristic and initial efficiency in addition to high capacity. The silicon oxide preferably has a spin density in the range of not less than 1×1017 spins/g to not more than 5×1019 spins/g. A negative electrode material for the lithium-ion secondary battery contains not less than 20% by mass of this silicon oxide as a negative electrode active material.

主权项

1. A silicon oxide to be used for a negative electrode active material of a lithium-ion secondary battery,
wherein a g-value measured by an ESR spectrometer is in the range of not less than 2.0020 to not more than 2.0050; and wherein, given that A, B, and C are the area intensities of peaks corresponding to about 420 cm−1, 490 cm−1 and 520 cm−1 respectively in a Raman spectrum measured by a Raman spectroscopy, A/B is not less than 0.5 and C/B is not more than 2.