To provide a fine carbon fiber excellent in characteristics such as dispersing property, close adherence, deterioration resistance, electroconductivity and heat conductivity on mixing with a basic material such as a resin, and various secondary batteries to begin with a Li ion secondary battery improved with its charging and discharging capacity and a battery improved with the strength of electrode plates and decomposition of electrolyte.

This finely graphitized carbon fiber is characterized with that its carbon fiber has a multiple-layered structure having a hollow structure at its central axis and a non-continuous graphene sheet having a broken surface at the fiber end part and a continuous surface bonded with the end part of the graphene sheet to which the end part of at least ≥1 piece of the graphene sheet approaches. The electroconductive material obtained from a composition using the fine carbon fiber, the secondary battery by using the same as an electrode material, and a gas occlusion material are provided.

COPYRIGHT: (C)2004,JPO