RMIT’s “cheaper, cleaner” proton battery has li-ion firmly in sights

Researchers from RMIT in Melbourne have made what they say is a “crucial step” towards cheap, sustainable battery storage after successfully demonstrating a working, rechargeable “proton battery” prototype.

In a paper published in the Science Daily journal on Wednesday, the RMIT team said its latest experiments had demonstrated the carbon-based battery was already comparable with commercially-available lithium-ion batteries, even though it was “far from being optimised.”

The breakthrough comes as a global battery boom – so far dominated by lithium-ion based products – starts to gear up, in the race to renewable power networks and electric vehicles.

The working prototype proton battery uses a carbon electrode as a hydrogen store, coupled with a reversible fuel cell to produce electricity.

During charging, the carbon in the electrode bonds with protons generated by splitting water with the help of electrons from the power supply, the paper says.

The protons are then released again and pass back through the reversible fuel cell to form water with oxygen from air to generate power.

Lead researcher, Professor John Andrews, says it is the carbon electrode plus protons from water that give the battery it’s environmental, energy and potential economic edge.

“Our latest advance is a crucial step towards cheap, sustainable proton batteries that can help meet our future energy needs without further damaging our already fragile environment,” Andrews said.

“As the world moves towards inherently-variable renewable energy to reduce greenhouse emissions and tackle climate change, requirements for electrical energy storage will be gargantuan.

“Powering batteries with protons has the potential to be more economical than using lithium ions, which are made from scare resources.

“Carbon, which is the primary resource used in our proton battery, is abundant and cheap compared to both metal hydrogen-storage alloys, and the lithium needed for rechargeable lithium ion batteries.”

Andrews said the team focus would now shift to further improving the battery’s performance and energy density through the use of “atomically-thin layered carbon-based materials” like graphene.

But he said their target – a proton battery that is truly competitive with lithium-ion batteries – was “firmly in sight.”

RMIT’s research on the proton battery has been partly funded by the Australian Defence Science and Technology Group and the US Office of Naval Research Global.