| 摘要 |
PROBLEM TO BE SOLVED: To improve the initial charging/discharging efficiency and cycle characteristic of a nonaqueous electrolyte secondary battery having a carbon negative electrode capable of storing/discharging lithium. SOLUTION: A coating layer made of an ionic conductive polymer, a water- soluble polymer, or alkaline metal salt is formed on the surface of a carbon negative electrode, the wettability between the carbon negative electrode and a nonaqueous electrolyte layer is improved, the decomposition of the nonaqueous electrolyte layer is suppressed, and the deposition of the decomposition product of the nonaqueous electrolyte layer on the surface of the negative electrode is suppressed. Even if the carbon negative electrode is made of a graphite carbon material and propylene carbonate is contained in the nonaqueous electrolyte layer in particular, the decomposition of this solvent on the surface of graphite is suppressed, and a good cycle characteristic is attained. |
