The present invention is able to provide an excellent battery. A battery according to one embodiment of the present invention is provided with a first electrode layer (6), a second electrode layer (7), and a charge layer (3) to which a charging voltage between the first electrode layer (6) and the second electrode layer (7) is applied. The charge layer (3) is capable of trapping electrons by forming an energy level in a bandgap by causing a photoexcited structural change of an n-type metal oxide semiconductor that is covered by an insulating substance. For example, this battery has a configuration wherein the charge layer (3) is formed three dimensionally.
