• 专利标题:   Carbon-coated composite material useful for negative electrode for lithium ion secondary battery, is obtained by coating surface of composite material containing carbon material and silicon with carbonaceous coating layer, where material has preset coefficient of variation in Raman spectrum.
  • 专利号:   JP2021187708-A
  • 发明人:   BAI Z X, FUJITA M, FUKUI T, ITO Y
  • 专利权人:   SHOWA DENKO KK
  • 国际专利分类:   C01B032/00, C01B032/05, C01B032/184, C01B033/029, H01M004/36, H01M004/38
  • 专利详细信息:   JP2021187708-A 13 Dec 2021 C01B-032/00 202205 Pages: 23 Japanese
  • 申请详细信息:   JP2021187708-A JP094312 29 May 2020
  • 优先权号:   JP094312

▎ 摘  要

NOVELTY - Carbon-coated composite material (c) is obtained by coating a surface of a composite material (a) containing a carbon material and silicon with a carbonaceous coating layer (b), where in the Raman spectrum of the carbon-coated composite material (c) by microscopic Raman spectroscopic analysis, the coefficient of variation of the ratio (ID/IG) of the R value (peak intensity (ID) near 1350 cm-1 to the peak intensity (IG) near 1580 cm-1) is 0.6 or less, and the coefficient of variation of the ratio (ISi/IG) of the 450-495 cm-1 to the peak intensity (ISi/IG) is 1 or less. USE - The material (c) is useful for a negative electrode active material, which is useful for a negative electrode for a lithium ion secondary battery (all claimed). ADVANTAGE - The material (c) suppresses deterioration of silicon by forming thin and uniform carbonaceous coating layer on the surface, and has excellent initial discharge capacity of lithium ions, initial coulomb efficiency and cycle characteristics.