A Hydrogen-bromine battery is a rechargeable flow battery in which hydrogen bromide (HBr) serves as the system’s electrolyte. During the charge cycle, as power flows into the stack, H2 is generated and stored in a separate tank. An additional product of the chemical reaction is HBr3, which is also an electrolyte and is mixed in the same tank as the HBr. During the discharge cycle H2 is consumed and energy is generated. The H2 is combined again with the HBr3 and the system returns to its initial stage with a full tank of HBr. The electrolyte suffers no degradation during the process and the system is self contained with no emissions.