Turning EV batteries into power storage

Vector, an electricity and gas distribution company in New Zealand, is exploring the possibility of turning end-of-life electric vehicle (EV) batteries into affordable power storage for homes and businesses.

In collaboration with Relectrify, an Australian battery control technology growth firm, the trial is testing the capability of EV batteries to be converted into electricity storage batteries.

End-of-life battery packs from New Zealand’s most common EV, the Nissan Leaf, were retrofitted with a battery management system developed by Relectrify, and connected to the grid via a standard hybrid inverter.

At the end of their life, when batteries can no longer provide the driving range and acceleration required to power EVs, they still hold up to 80 per cent of their storage capability.

During the trial, Nissan Leaf battery packs were repurposed to supply 15kWh of usable energy at power levels up to 10kW - or enough electricity to power a standard New Zealand solar home for one to two nights.

Cristiano Marantes, head of engineering at Vector, says the trial’s results open up significant possibilities.

"As electric vehicles become more and more popular in New Zealand, they bring with them an increasing supply of lithium-ion batteries. Once these batteries reach the end-of-life, they provide no further use in a car."

"We have successfully proven that with Relectrify control technology, these batteries can be kept out of the landfill and hold significant value for further use. This is fantastic from both a business opportunity and sustainability point of view.

"The results open up an opportunity to build affordable power storage for our distribution network here in Auckland to help solidify its resiliency. While this requires some further development towards scaling, the possibility of what we could achieve is really exciting."

Relectrify’s co-founder and CEO, Valentin Muenzel, says the company is seeing significant interest in its control technology across geographies and applications.

"Vector brings extensive insight into distribution requirements and storage opportunities, alongside an interest in solutions that solve the key problems of tomorrow. Relectrify is positioned to enable collaborators such as Vector to build uniquely affordable and capable battery storage products, including for households, businesses, and the power grid."

Relectrify’s work on this innovative project has received support by the Australian Government Department of Industry, Innovation and Science under the Entrepreneurs’ Programme.