Achieved is an electricity storage device having a low internal resistance and a high energy density. In a pore distribution, which is obtained for a carbon material using a BJH method and is plotted on a graph with a pore diameter D on the abscissa and a derivative ΔV/ΔD of a pore volume per unit mass or unit volume with respect to the pore diameter D on the ordinate, a ratio M1/M2 of the maximum value M1 of the derivative ΔV/ΔD in an interval of the pore diameter D from 10 to 100 nm with respect to the maximum value M2 of the derivative ΔV/ΔD in an interval of the pore diameter D from 2 to 10 nm is 1.5 or more.