REDOX FLOW BATTERY

A redox flow battery charged and discharged by supply of a positive electrode electrolyte stored in a positive electrode tank and a negative electrode electrolyte stored in a negative electrode tank to a battery element, in which the positive electrode electrolyte contains a Mn ion as a positive electrode active material, and the positive electrode tank includes a positive electrode charging pipe opening to a position close to a liquid level of the positive electrode electrolyte in the positive electrode tank, and a positive electrode discharging pipe opening to a position close to the bottom of the positive electrode tank. This redox flow battery can include a stirring mechanism for stirring the electrolytes in the tanks, and can include a connection pipe connecting the positive electrode tank to the negative electrode tank.