How plants could power better batteries

Professor Thomas Nann said the electrolyte his team has created would make aluminium batteries cheaper and easier to produce. Photo / Victoria University

Could plants be the key to safer, greener batteries?

A New Zealand-led research team has created a new electrolyte – one of several key parts in a battery, acting as a conductor for electricity.

Professor Thomas Nann, of the MacDiarmid Institute for Advanced Materials and Nanotechnology at Victoria University, said the electrolyte would make aluminium batteries cheaper and easier to produce.

"It is more affordable than the ionic liquids currently used in aluminium batteries, and it is also more sustainable, as our electrolyte can be made from plants."

This research was part of a wider project led by Nann to create better battery alternatives.
Batteries were currently made out of lithium and cobalt, but Nann said problems with these materials were quickly becoming apparent.

"Lithium and cobalt are potentially dangerous substances," he said.

"Damage to batteries containing these substances can make them explode. They are also toxic, leading to several deaths every year from children swallowing these batteries.

"Nor are they easily recyclable, and we are running low on available sources of the raw materials.

"If we do not find alternate sources of lithium and cobalt, we will eventually run out of the resources we currently use to make batteries."

While aluminum was a good alternative, the technology for creating aluminium batteries lagged behind other battery technology—although it was catching up.

However, aluminium was safer to use, as it was non-toxic and not at risk of exploding, was recyclable, and the most abundant metal on Earth.

"This new electrolyte is just another step towards improving aluminium battery technology and making it suitable for commercial use."

Nann and his team had so far tested their electrolyte with a standard graphite-based battery, with plans to adapt the electrolyte so it can be used in batteries that use better performing materials in the future.