Researchers demonstrate working rechargeable "proton battery"

Researchers from RMIT University have demonstrated for the first time a working rechargeable "proton battery" that could be a game changer for powering cars, homes, and gadgets. The rechargeable battery has the potential with future development of storing more energy than current lithium-ion batteries. The team also notes that with modifications and scaling up, the proton battery tech could also be used for medium-scale storage on electricity grids.

The prototype proton battery uses a carbon electrode as a hydrogen store along with a reversible fuel cell to produce electricity. That electrode combined with protons from water is key to the environmental energy and potential economic edge over current batteries. When charged the carbon in the electrode bonds with protons generated from splitting water with the help of electrons from the power supply.

The scientists say that protons are released again and pass back through the reversible fuel cell to form water with oxygen from the air to generate power. No emissions are released, and the carbon doesn't burn in this process. The small proton battery the scientists created has an active surface of 5.5 square centimeters and could store as much energy as commercially-available lithium-ion batteries.

The team points out that storage capacity was before the battery had been optimized. The major potential advantage for the battery is that it has much higher energy efficiency than conventional hydrogen systems. This experiment has shown that a porous activated-carbon electrode made from phenolic resin could store about 1 wt% hydrogen in the electrode.

The team says that energy storage per unit is already comparable with commercial lithium batteries despite the proton battery being far from optimized. The team was able to generate a maximum cell voltage of 1.2 volt.