| 摘要 |
PROBLEM TO BE SOLVED: To provide a battery having a large capacity and being superior in cycle characteristics in charging/discharging by setting a negative electrode to a sintered body with silicon or its compound set to the negative electrode active material and limiting the lithium quantity stored in the negative electrode active material to a specific range. SOLUTION: The quantity of lithium stored in a negative electrode active material is preferably limited to 200-800 mAh per active material 1 g, because in this region, the collapse of the crystal structure of silicon and generation of substances without involved in the charging/discharging reaction which are through to be causes of the irreversible capacity are supposed. The negative electrode is so fabricated that silicon powder is heat treated under the presence of carbon material or a material carbonized by heat treatment in non-oxidation environment in such a range as preventing the silicon from melting so as to prepare the treated powder, binder and solvent is added to the treated powder to prepare coating liquid, the coating liquid is applied to a conductive base element to form a coating film, and then it is heat treated at a prescribed temperature, integrated with a conductive base element, and sintered. |
