| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem that, even when an active material layer is formed by imparting an expansion space thereto, this is not enough for relieving stresses occurring on boundary surface between a current collector and the active material, causing separation from the boundary surface, and even though this will not lead to separation from the current collector, part of the active material may be pulverized and made to fall off along with expansion and contraction of the active material, resulting in that the active material separated from the current collector or the fine particulate substance having fallen off from the active material causes current collection properties to deteriorate because of the lack of conductivity, bringing about a reduction in battery capacity or a reduction in output characteristic due to charges and discharges.SOLUTION: The present invention constitutes a mode in which an active material containing silicon capable of occluding and discharging at least lithium ions is formed while being imparted with an expansion space, and a conductive material layer prepared by dispersing conductive material in a polymer having electrolyte swelling properties is formed on the surface of the active material. |
