A carbon-coated active material composite in which charge migration of lithium ions occurs at an interface between a carbonaceous film and an electrode active material, and wherein the carbon-coated material composite comprises: an electrode active material as a main component, one selected from a group consisting of lithium cobaltate, lithium nickelate, lithium manganate, lithium titanate, and Li x A y D z PO 4, with A representing one or more selected from a group consisting of Co, Mn, Ni, Fe, Cu and Cr, D representing one or more selected from a group consisting of Mg, Ca, S, Sr, Ba, Ti, Zn, B, Al, Ga, In, Si, Ge, Sc, Y, and rare earth elements, wherein 0<x<2, 0<y<1.5, and 0<z<1.5, a carbonaceous film coated on the surface of the electrode active material particles, with the carbonaceous film coating 70% or more of surfaces of the particles of the electroactive material, having a density of 0.1 g/cm 3 to 1.5 g/cm 3 and a film thickness of 0.1 nm to 10 nm, a value of a carbon supported amount with respect to a specific surface area of particles of the electrode active material, calculated as [carbon supported amount expressed in g]/[specific surface area of the particles of the electrode active material expressed in m 2 /g] is in a range of 0.01 to 0.5 g 2 /m2, and an activation energy is a value measured using an electrolyte solution obtained by mixing ethylene carbonate and diethyl carbonate at a 1:1 ratio, so that an activation energy of an insertion and removal reaction of lithium ions occurring at an interface between the carbon-coated active material composite and an electrolytic solution is in a range of 45 kJ/mol to 85 kJ/mol, wherein the carbonaceous film is generated by thermal decomposition of an organic compound of a dried substance and has a density that has been optimally adjusted by the loss of pore-forming agents. an electrode active material as a main component, one selected from a group consisting of lithium cobaltate, lithium nickelate, lithium manganate, lithium titanate, and Li x A y D z PO 4, with A representing one or more selected from a group consisting of Co, Mn, Ni, Fe, Cu and Cr, D representing one or more selected from a group consisting of Mg, Ca, S, Sr, Ba, Ti, Zn, B, Al, Ga, In, Si, Ge, Sc, Y, and rare earth elements, wherein 0<x<2, 0<y<1.5, and 0<z<1.5, a carbonaceous film coated on the surface of the electrode active material particles, with the carbonaceous film coating 70% or more of surfaces of the particles of the electroactive material, having a density of 0.1 g/cm 3 to 1.5 g/cm 3 and a film thickness of 0.1 nm to 10 nm, a value of a carbon supported amount with respect to a specific surface area of particles of the electrode active material, calculated as [carbon supported amount expressed in g]/[specific surface area of the particles of the electrode active material expressed in m 2 /g] is in a range of 0.01 to 0.5 g 2 /m2, and an activation energy is a value measured using an electrolyte solution obtained by mixing ethylene carbonate and diethyl carbonate at a 1:1 ratio, so that an activation energy of an insertion and removal reaction of lithium ions occurring at an interface between the carbon-coated active material composite and an electrolytic solution is in a range of 45 kJ/mol to 85 kJ/mol, wherein the carbonaceous film is generated by thermal decomposition of an organic compound of a dried substance and has a density that has been optimally adjusted by the loss of pore-forming agents.