To efficiently take out electrical energy by utilizing magnetism without utilizing dynamic energy of a mechanical movable part or the like.

This battery is provided with a reaction tube 1 having electrodes 21, 22 on both end parts thereof and a reaction liquid 3 sealed therewithin, and magnets 4 such as superconducting magnets only on one end part of the reaction tube 1. A magnetic field produced by the magnets 4 is applied so as to be directed from the electrode 22 side toward the reaction liquid 3 side and electrical energy is taken out by the electrodes 21, 22 from a chemically non- equilibrated system in the reaction tube 1.