Disclosed is a highly efficient electrical storage device, which uses a fiber cathode and a fiber anode, and in which lithium ions are intercalated. Further disclosed is a method for producing such an electrical storage device. The electrical storage device is provided with: a fiber cathode wherein a cathode active material coat layer containing a transition metal oxide represented by chemical formula 1 (Li1-xAx)aMbXcOd (in chemical formula 1, A is at least one alkali metal chosen from the group consisting of Na, K, Rb, and Cs; M is at least one transition metal chosen from the group consisting of Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Nb, Mo, Ru, Pd, Ag, Ta, W, Ce, Pr, Sm, Eu, and Pb; X is at least one representative element chosen from the group consisting of B, Al, Si, P, S, Ga, and Ge; and 0<a=6, 1=b=5, 0=c=4, 0<d=12, 0=a / b=4, 0=x=0.5) is formed on the surface of a conductive fiber; a fiber anode wherein an anode active material coat layer is formed on the surface of a conductive fiber; a separator; and an electrolyte.