LITHIUM SECONDARY CELL, NEGATIVE ELECTRODE MATERIAL FOR IT, AND IMPROVING METHOD THEREFOR

摘要

PROBLEM TO BE SOLVED: To increase the energy capacity of the material used as the negative electrode for a lithium secondary cell, and to improve the output characteristics and charge/discharge cycle characteristics. SOLUTION: The negative electrode material for a lithium secondary cell is covered with a metal compound thin-film. The thickness of the thin-film is preferred to be 2-50 nm. The metal compound thin-film may be acquired by either physical deposition method or chemical deposition method, otherwise by vapor-phase deposition method or liquid-phase deposition method. The lithium secondary cell and the negative electrode material for it are thus acquired.