Old Rivian batteries now power part of a factory in Illinois
Rivian and the battery company Redwood Materials announced on April 14, 2026 that old Rivian vehicle battery packs now power part of the Rivian factory in Normal, Illinois. A stationary storage system, batteries built into a building rather than a moving car, uses more than 100 of those old packs to provide 10 megawatt hours of dispatchable power, stored electricity the factory can call on immediately, cutting cost and easing strain on the local grid during peak demand, the hours each day when the most people draw power at once. RJ Scaringe, founder and chief executive officer of Rivian, said old batteries still have work left to do.
EVs represent a massive, distributed and highly competitive energy resource.
RJ Scaringe, Founder and chief executive officer of Rivian. Source 1.
Why the old packs still work
Reading a Redwood release directly, not just news coverage of the deal, shows why these old packs are worth reusing at all. Redwood says the packs it accepts for reuse generally still hold 50 to 80% of their usable life once they leave a car, before taking on grid storage work Redwood calls less demanding. Redwood also says its storage systems passed a tougher fire safety test, UL 9540A 6th Edition, a large scale test for fire and deflagration, a rapid fire that can spread fast through a battery system, matching a 2026 national safety standard for stationary battery installations. An engineer at UL Solutions, an independent testing body with no stake in either company, confirmed the result.
One factory against a whole country of demand
Redwood frames the Illinois system as one small piece of a much larger need. Redwood estimates the United States needs over 600 gigawatt hours of storage capacity by 2030, to meet growing demand and stabilize peaks in power use, an amount Redwood compares to running the Hoover Dam continuously for 2 months. Converted to the same unit as the Illinois system, that estimate equals about 600,000 megawatt hours, so the system running today in Normal is many thousands of times smaller than what Redwood says the whole country will need.
Both figures come from Redwood Materials own estimate. The national figure is a Redwood projection, not an independent count, and the two bars describe very different scales, 1 factory against a whole country. The Illinois system is not shown here as a meaningful fraction of the national need.
Show the numbers
| Illinois system online now | 10 |
| United States storage needed by 2030, Redwood estimate | 600,000 |
The money behind the plan
Redwood closed a Series E round, its fifth major round of outside investment, in January 2026 at 425,000,000 dollars, up from the 350,000,000 dollars first announced for the same round, with new investor Google joining continuing investors Capricorn and Goldman Sachs Alternatives. The money is meant to accelerate Redwood energy storage business, the same business line building the Illinois system, alongside its battery recycling and critical minerals work. JB Straubel, founder and chief executive officer of Redwood Materials, said the Illinois system shows where that business is headed.
This is a scalable model for how we add meaningful energy capacity in the near term.
JB Straubel, Founder and chief executive officer of Redwood Materials. Source 1.
Both figures describe the same Series E round, before and after additional investors joined, including Google. Redwood says the funding is meant to accelerate its energy storage business, the same business line building the Illinois system.
Show the numbers
| Amount first announced | 350 |
| Final close in January 2026 | 425 |
Other automakers are lining up for the same deal
Rivian is not the only automaker Redwood is courting for this business. Redwood launched its Redwood Energy business in June 2025 and signed a memorandum of understanding, a formal agreement to work together though not yet a binding contract, with General Motors in July 2025 to explore similar grid storage work, and separately reached an agreement with Ford, announced in December 2025. Each deal points to the same idea the Rivian factory now runs on, that a used electric car battery still has years of paid work left in it once it leaves the road.