TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Properties: The particles of carbonaceous base material have cores having porosity of 10-20% with respect to total volume of carbonaceous base material. The plane interval (d002) of plane (002) of crystalline carbonaceous base material is 0.337-0.338 nm. The average particle diameter of carbonaceous base material is 10-20 mu m. The silicon-based nanowire has average diameter of 10-500 nm and average length of 0.1-100 mu m. The length/width ratio of silicon-based nanowire is 100 or more. Preferred Composition: The carbonaceous base material comprises crystalline carbonaceous material preferably chosen from natural graphite, artificial graphite, expandable graphite, graphene, carbon black and/or fullerene soot. The silicon-based nanowire comprises silicon, silicon oxide (SiOx, where x is more than 0 to 2), and alloy of silicon and element (Z), where Z is alkali metal, alkali-earth metal, group XIII element, group XIV element, group XV element, group XVI element, transition metal and/or rare-earth element, and excludes silicon. The silicon-based nanowires are grown directly on the carbonaceous base material, preferably in presence of metal catalyst(s) chosen from platinum, iron, nickel, cobalt, gold, silver, copper, zinc and/or cadmium. The amount of carbonaceous base material and silicon-based nanowire is respectively 60-99 wt.% and 1-40 wt.%, with respect to total content of carbonaceous base material and silicon-based nanowire. The negative active material further comprises other carbonaceous particles comprising natural graphite, artificial graphite, expandable graphite, graphene, carbon black, fullerene soot, carbon nanotubes, and/or carbon fibers. The negative electrode further comprises conductive agent(s) chosen from carbon black, acetylene black, Ketjen black (RTM: electroconductive carbon black), carbon fiber, copper, nickel, aluminum, silver and/or conductive polymer.    TECHNOLOGY FOCUS - POLYMERS - Preferred Composition: The binder comprises polyvinylidenefluoride, polyvinylidenechloride, polybenzimidazole, polyimide, polyvinylacetate, polyacrylonitrile, polyvinylalcohol, carboxymethylcellulose, starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, polyethylene, polypropylene, polystyrene, polymethylmethacrylate, polyaniline, acrylonitrile-butadiene-styrene, phenol resin, epoxy resin, polyethylene terephthalate, polytetrafluoroethylene, polyphenylsulfide, polyamideimide, polyetherimide, polyethylenesulfone, polyamide, polyacetal, polyphenyleneoxide, polybutylene terephthalate, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene butadiene rubber and/or fluoride rubber. The content of binder is 1-15 parts weight with respect to 100 parts weight of negative active material.