Second-Life EV Batteries Find Grid Storage Applications
Second-life EV batteries at $50-80/kWh are being repurposed for grid storage, with 200 GWh expected annually by 2030, offering significantly lower costs than new battery installations.
Electric vehicle batteries that have degraded below the threshold for automotive use — typically retaining 70-80% of original capacity — are finding second lives in stationary energy storage applications. This reuse pathway extends battery value, reduces waste, and provides lower-cost storage for grid and commercial applications.
The supply of second-life EV batteries is growing rapidly as early-generation electric vehicles reach the end of their automotive life. By 2030, an estimated 200 GWh of EV batteries will become available for second-life applications annually — enough to support a significant portion of grid storage needs. Companies including ReJoule, Repurpose Energy, and B2U Storage Solutions are scaling operations to aggregate, test, and deploy second-life batteries.
B2U Storage Solutions operates the world's largest second-life battery storage facility, a 25 MWh installation in Lancaster, California, that participates in CAISO wholesale energy markets. The facility uses batteries retired from Honda and Nissan electric vehicles, reconfigured into stationary storage racks with new power electronics and battery management systems.
The economics of second-life storage are compelling. Used EV batteries can be procured at $50-$80 per kWh — less than half the cost of new lithium-ion cells for stationary applications. Even accounting for reduced capacity and shorter remaining lifespan (typically 5-10 additional years in stationary use), the levelized cost of storage from second-life batteries is highly competitive.
Quality control and safety are critical considerations. Each battery pack must be individually tested and graded to determine its remaining capacity and internal resistance. Advanced diagnostic equipment using AI and machine learning algorithms can rapidly characterize battery health, enabling efficient sorting and matching of packs for second-life systems.