MANUFACTURING METHOD OF COMPOSITE GRAPHITE PARTICLE FOR LITHIUM ION SECONDARY BATTERY NEGATIVE ELECTRODE

摘要

PROBLEM TO BE SOLVED: To provide a manufacturing method of a composite graphite particle having a high discharge capacity and high initial charge efficiency and further having excellent high temperature durability and low resistance.SOLUTION: The manufacturing method includes: a first mixing step of mixing a graphite particle (a) internally having a void and an organic solution and filling the interval void of the graphite particle (a) with the organic solution to obtain a graphite particle (b) filling the internal void of the graphite particle (a) with the organic solution; a second mixing step of continuously mixing the graphite particle (b) and a carbonaceous precursor (y) after the first mixing step and depositing the carbonaceous precursor (y) on a surface of the graphite particle (b) to obtain a graphite particle (c) depositing the carbonaceous precursor (y) on the surface of the graphite particle (b); and a calcination step of calcining the graphite particle (c) obtained in the second mixing step at a temperature of 700 to 1400°C under an inactive atmosphere and modifying the carbonaceous precursor (y) into carbonaceous matter to obtain a compote graphite particle (d) covering the surface of the graphite particle (a) with the carbonaceous matter.