A mixture of amorphous PAHs and at least one of a carrier ion storage metal, a Sn compound, a carrier ion storage alloy, a metal compound, Si, Sb, and SiO2 is used as the negative electrode active material. The theoretical capacity of amorphous PAHs greatly exceeds that of a graphite-based carbon material. Thus, the use of amorphous PAHs enables the negative electrode active material to have a higher capacity than in the case of using the graphite-based carbon material. Further, addition of at least one of the carrier ion storage metal, the Sn compound, the carrier ion storage alloy, the metal compound, Si, Sb, and SiO2 to the amorphous PAHs enables the negative electrode active material to have a higher capacity than the case of only using the amorphous PAHs.