QUALITY CONTROL METHOD FOR NEGATIVE ELECTRODE ACTIVE MATERIAL OF LITHIUM-ION SECONDARY BATTERY, MANUFACTURING METHOD FOR NEGATIVE ELECTRODE OF LITHIUM-ION SECONDARY BATTERY, MANUFACTURING METHOD FOR LITHIUM-ION SECONDARY BATTERY, NEGATIVE ELECTRODE OF LITHIUM-ION SECONDARY BATTERY, AND LITHIUM-ION SECONDARY BATTERY

摘要

The invention addresses the problem of providing a quality control means that is used for a negative electrode active material of a lithium-ion secondary battery having an amorphous carbon layer at the surface and is capable of performing a quality control with sufficient accuracy even if the thickness of the amorphous carbon layer becomes thinner. In order to solve said problem, provided is a quality control method for a negative electrode active material of a lithium-ion secondary battery having an amorphous carbon layer at the surface, in which the appearance of the variations of a plurality of D/G ratios is used as an indicator of the quality control, said plurality of D/G ratios being obtained by, after heating an object to be tested at a predetermined heating temperature, performing a first process a predetermined number of times with changing the heating temperature, said first process being a process for measuring the D/G ratios by Raman scattering spectroscopy measurement.