| abstract |
(57) [Problem] To provide a lithium ion secondary battery which has a high capacity and a high initial efficiency, and can maintain a high capacity even during high-speed charge and discharge. SOLUTION: A carbonaceous material obtained by coating the surface of a graphitic carbonaceous material with a carbonizable organic material, calcining and pulverizing the amorphous carbon-coated graphite-based carbonaceous material with an acidic or alkaline solution is used as a negative electrode. Lithium-ion secondary battery used as a battery. |