Redwood Materials finds retired EV batteries typically lose only 20% capacity
Colin Campbell · Repurposing EV batteries for grid storage · Jul 24, 2025 · at 5:18
Colin Campbell, CTO of Redwood Materials, explains the typical physical and electrochemical state of retired automotive battery packs when they arrive at their facilities.
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“So from a physical perspective they're usually almost new. And then from an electrical and electrochemical perspective we receive them when a customer might get frustrated with them, typically. So that's something like I've lost 20% of my range, or the acceleration isn't what it used to be. Something like 20% increase in impedance, 20% decrease in capacity is, is typical for what we see.”
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