How Used EV Batteries Get A Second Life Powering Homes

The batteries used to power electric vehicles aren't your everyday Alkaline batteries. Most EVs are powered by lithium-ion batteries, which have long lifespans, can be recharged relatively quickly, and are high-density, offering a lot of energy in a small package. They also have a slow discharge rate, meaning they aren't losing a lot of energy when not in use. Perfect for use in electric cars, but also very difficult to dispose of without harm to the environment.

Rechargeable lithium-ion batteries are also used in cellphones, laptops, power tools and more, and can't simply be thrown away with the kitchen trash. Most EV batteries also contain cobalt, nickel, manganese, silicon and electrolytes. They're not only harmful to the environment, but they can spark fires if not disposed of properly at recycling centers. Then, the recycling process requires special facilities, is expensive, and a time-consuming process.

EV batteries have a life of about 10 to 20 years, so batteries from the first generation of EVs are reaching the end of the road. Rather than simply disposing of them, companies like General Motors are taking a different route; finding new life for these behemoth batteries as vessels for energy storage for wind and solar power. This storage allows wind and solar power to feed the grid at night or when the winds die down, and can power everything from homes to hospitals.

To help keep EV batteries out of landfills, General Motors partnered with Redwood Materials to figure out the best way to reuse them. Batteries that still have enough capacity to store energy on a stationary basis are perfect for use in something called "microgrids," which according to IBM, are "small-scale power grids that operate independently to generate electricity for a localized area." GM and Redwood Materials have installed used EV batteries in a microgrid in the aptly-named Sparks, Nevada, which is providing backup power to an AI infrastructure company.

In California, one of the most sustainable states in the U.S., another company called B2U Storage Solutions opened a solar farm that uses old batteries from Honda Clarity and Nissan Leaf EVs to store 28 megawatt-hours of power. That's enough to power about 9,500 homes. Giving used EV batteries a second life not only keeps them out of the landfill, but it helps to alleviate the environmental impact of making them in the first place. 

The process of extracting the minerals needed for these batteries can be harmful to the environment, and experts have concerns about the sustainability of not only mining, but manufacturing lithium-ion batteries. In July 2025, GM and Redwood Materials signed a non-binding memorandum of understanding to advance the deployment of energy storage systems using new U.S.-manufactured batteries from GM and second-life battery packs from GM electric vehicles. This collaboration may not just power homes, but facilities that require high levels of energy such as data centers.