Electrode material for rechargeable lithium battery, electrode structural body comprising said electrode material, rechargeable lithium battery having said electrode structural body, process for the production of said electrode structural body, and process for the production of said rechargeable lithium battery

An electrode structural body for a rechargeable lithium battery, comprising a fine powder of a silicon-based material whose principal component is silicon element, wherein the fine powder has an average particle size (R) in a range of 0.1 μm≦R<0.5 μm, the fine powder has an oxidation preventive surface coat film which covers the surface of the fine powder, the oxidation preventive surface coat film comprises an oxide film, the fine powder contains oxygen element (O) in an amount in a range of 0.8 wt. %≦[O]≦4.6 wt. %, and the fine powder contains silicon element (Si) in an amount in a range of 95.0 wt. %≦[Si]≦98.8 wt. %.