SIOX, AND DEPOSITION MATERIAL FOR BARRIER FILM AND NEGATIVE ELECTRODE ACTIVE MATERIAL FOR LITHIUM ION SECONDARY BATTERY EACH UTILIZING SAME

摘要

Disclosed is an SiOx which generates an H2O gas in an amount of 680 ppm or less as detected in a temperature range from 200 to 800°C in a thermally evolved gas analysis. In the SiOx, it is preferred that the amount of the H2O gas generated be 420 ppm or less. It is also preferred that the peak intensity (P1) which is a peak intensity at an Si peak point appearing around 2? = 28° and the base intensity (P2) which is an intensity appearing at a peak point that is assumed based on an average gradient as determined in a backward and a forward of the aforementioned peak point in a graph produced by X-ray diffraction meet the requirement represented by the following formula: (P1-P2)/P2 = 0.2. When the SiOx is used as a deposition material, a deposited film that does not undergo the occurrence of splashing during the formation of the film and has excellent gas barrier performance can be produced. When the SiOx is used as a negative electrode active material for a lithium ion secondary battery, the initial efficiency of the lithium ion secondary battery can be maintained at a high level.