NEGATIVE ELECTRODE FOR NONAQUEOUS ELECTROLYTE SECONDARY BATTERY, AND NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

摘要

PROBLEM TO BE SOLVED: To provide a negative-electrode for a nonaqueous electrolyte secondary battery capable of fully suppressing a generated amount of gas generated by decomposition of propylene carbonate on the surface of the negative-electrode, at the charging of the nonaqueous electrolyte secondary battery.

SOLUTION: The negative-electrode for the nonaqueous electrolyte secondary battery 21 is provided with a negative-electrode current collector 21a and a negative-electrode active material layer 21b supported on the surface. The negative-electrode active material layer 21b contains amorphous region containing graphite particles and mesocarbon microbeads. The amorphous region containing graphite particles have a crystal region and an amorphous region formed on the surface of the particle by applying a mechanical milling treatment on the graphite; the ratio of a region 3R, with respect to a total sum of the region (3R) showing rhombohedral structure and a region (2H) showing hexagonal crystal structure is 21% or more and 40% or less; and a content ratio of the amorphous region containing graphite particles and the mesocarbon microbeads in the negative-electrode active material layer 21b is in the range of 30:70-70:30.

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