Rivian's Money-Saving Strategy Involves Reusing Old Batteries - Jalopnik
tags:Rivian's Normal, Illinois factory will soon be drawing power from its own used battery packs. The company has partnered with Redwood Materials — founded by Tesla co-founder and former CTO J.B. Straubel — to build a second-life energy storage system directly onsite. This partnership marks the first time a repurposed battery system has been deployed by a U.S. automaker's manufacturing facility.
The initial installation will comprise more than 100 used Rivian battery packs, assembled into a system capable of storing 10 megawatt-hours of energy. Rivian supplies the used battery packs while Redwood integrates them into what it calls a Redwood Energy system, operated by the company's in-house management software. That software is designed to handle packs with varying states of health, running them together as a single coordinated power source.
The practical function on the factory floor is straightforward enough. Stored energy can be discharged during peak demand periods to reduce the amount of power Rivian needs to draw from the local utility in moments when grid electricity costs increase.
For a plant that is ramping production of the R2 alongside the R1S and R1T, those peak demand charges are only going to increase. A battery buffer built from second-life packs addresses that cost problem while making use of assets that would otherwise head directly to recycling.
Retired batteries still have value
EV batteries don't lose their usefulness when they're pulled from a vehicle. According to Redwood Materials, even degraded battery packs frequently retain more than 50% of their original capacity — enough life to make them genuinely valuable for stationary storage applications.
Redwood launched its energy division in mid-2025 specifically to capture this disparity — repurposing packs between the end of their useful automotive life and their eventual recycling. The company has already deployed an even larger system at its Nevada campus, using 792 packs to build a 63 MWh microgrid that, of course, powers an AI data center. The Rivian installation is smaller, but it's notable as the first time Redwood has integrated its storage into an automotive plant.
For Rivian, the deal solves two problems at once. It reduces energy costs at the factory, and it creates a productive use for warranty returns, engineering prototypes, and high-mileage packs that still carry usable capacity. Redwood, meanwhile, now has an auto plant as a reference customer with a growing supply of second-life battery packs — a more demanding benchmark than a data center.
Rivian CEO RJ Scaringe framed it as a grid-health argument as much as a cost one. Using vehicle batteries beyond their automotive life contributes to a more flexible and reliable energy system. Straubel's case is simpler — the U.S. will need more than 600 GWh of storage by 2030, and the batteries to do it are already sitting in EVs across America.