An electrochemical device such as a battery and a fuel cell having two electrolytes between the anode and the cathode. The electrochemical device is preferably arranged with an alkaline electrolyte in contact with the anode and an acidic electrolyte in contact with the cathode. The electrolytes are separated by a bipolar membrane that preferably also provides ionic conductivity between the two electrolytes and also generates a supply of protons and hydroxide anions. The electrochemical device achieves fifty percent higher operating voltage and power compared to fuel cells with a single electrolyte.