29 Dec 2020

The search for a better battery

From Summer Times, 9:31 am on 29 December 2020

The race to discover the next sustainable and long lasting battery is on right here in New Zealand's capital.

Shalini Divya portraits against blue sky and Te Toki A Rata bavkgrounds

Photo: © Victoria University of Wellington. All rights reserved.

The reusable battery of choice today is lithium-ion - it is in our phones, torches, e-bikes - you name it.

Wellington based scientist, Dr Shalini Divya has just completed her PhD in Chemistry and has started a company hoping to create a more sustainable and more easily recyclable alternative.

She told Summer Times with Jesse Mulligan that unless more sustainable ways of storing energy are developed, the move to renewable energy won’t be realised.

“You have these lithium batteries coming in all shapes and sizes (from car batteries down to your AAAs) so, it’s about reducing the pressure on lithium-ion batteries because lithium-ion cobalt are the major components of these batteries and we are going to run out of these resources pretty soon.

“So, I think it’s high time that we as scientists start focussing on alternatives.”

Dr Divya admitted she had never heard of aluminium-ion batteries before she started her PhD but is a big believer in their potential as an alternative to lithium-ion.

She said there are several advantages to using aluminium over lithium in batteries, including its abundance on the earth’s crust, that it’s easily recyclable and reusable and that it does not need to be unethically mined like lithium is in South America and Africa.

However, aluminium still has its challenges, she said.

“There is this other thing called the energy density, now energy density is basically the amount of energy a particular battery can store, so right now we are not able to compete with lithium, but that’s what my job is, so I’m trying to design these batteries in a better way so that we are able to compete with Tesla in the coming years.”

Tesla, the electric car manufacturer in the US, produces nickel-cobalt-aluminum batteries with Panasonic for its vehicles.

Dr Divya said her company, only in its infancy and not yet registered in New Zealand, is at least five-10 years behind its competitors like Tesla.

However, she believes with the help of more investors aluminium batteries will become the sustainable energy storage device the world needs.