"Used EV Batteries Could Upend The Race For Long-Duration Storage"

"Redwood Materials says second-life batteries are the cheapest form of long-duration storage. If true, battery startups are in trouble — and renewables are in luck." 

"Energy storage is having a moment — but the batteries that are taking off today only have enough juice to provide a few hours of grid power. Developers technically could stack up more batteries for longer-term storage, but that gets prohibitively expensive. For a renewables-dominated grid to ride out days of poor solar production or even just an entire night, a breakthrough in cost-effective, longer-term storage is needed.

Over the last couple decades, venture capitalists have recognized this transformative possibility and heaped billions of dollars into the sector known as long-duration energy storage, or LDES. They have little to show for their efforts. The startups that haven’t gone bankrupt have built some factories and early installations, but have not built any particularly large-scale projects, at least in the U.S.

A few weeks ago, I saw something in the desert outside Reno, Nevada, that got me thinking the investors and startups may have been barking up the wrong tree all along.

Former Tesla Chief Technology Officer JB Straubel unveiled a surprising new project in June at the Tahoe campus of his lithium-ion recycling company, Redwood Materials. Instead of ripping apart old electric vehicle battery packs, his engineers arranged them across a patch of desert and hooked them up to an adjacent solar field. This assemblage now stores so much clean power that it can run a small on-site data center, rain or shine, night or day."

Julian Spector reports for Canary Media August 6, 2025.

Source: Canary Media, 08/07/2025