The disclosed technology generally relates to energy storage devices, and more particularly to redox batteries. In one aspect, a redox battery comprises a first half cell and a second half cell. The first half cell comprises a positive electrolyte reservoir comprising a first electrolyte contacting a positive electrode and has dissolved therein a first redox couple configured to undergo a first redox half reaction. The second half cell comprises a negative electrolyte reservoir comprising a second electrolyte contacting a negative electrode and has dissolved therein a second redox couple configured to undergo a second redox half reaction. The redox battery additionally comprises an ion exchange membrane separating the positive electrolyte reservoir and the negative electrolyte reservoir. The first half cell, the second half cell and the ion exchange membrane define a redox battery cell that is sealed in a casing.