Used EV batteries gain second life as home power storage systems

April 10, 2025 – The conversation around electric vehicle batteries is shifting from end-of-life disposal to second-life applications. In a recent development in India, Union Minister Nitin Gadkari inaugurated an EV startup in Nagpur, emphasizing that used lithium-ion batteries from electric vehicles can serve as a "second source" of power for homes. This concept, already gaining traction in the United States, could reshape how consumers and utilities think about energy storage.

Gadkari stated that repurposing EV batteries as stationary energy‑storage systems would improve the overall value proposition of electric mobility. Instead of being discarded after their automotive life—typically when capacity drops to 70–80%—these batteries can still hold enough energy to power a household for several hours, especially during peak demand or outages.

The startup, founded by Ashish Dokania, focuses on retrofitting conventional petrol‑powered mopeds into electric vehicles. The company already operates plants in Bengaluru and Hyderabad and has expanded to Nagpur. Dokania noted that lead‑acid batteries are cheaper but have shorter lifespans, while lithium‑ion packs can run for up to 50,000 kilometers. Portable batteries can also be charged at home.

Gadkari urged the team to make retrofitting affordable so that people from various economic backgrounds can embrace EVs. The retrofit kit includes a battery, motor, controller, rear wheel, display, throttle, wiring, and necessary mounts, with modifications to the swing arm and suspension. Battery‑related components account for nearly 50% of the total cost.

Dokania explained that the retrofitting model allows existing petrol mopeds to be converted into EVs without replacing the entire vehicle, reducing both cost and environmental impact during the transition.

U.S. parallel and market context

While the Indian announcement highlights a local initiative, the idea of second‑life EV batteries is already being tested in the United States. General Motors, through its Ultium platform, has partnered with energy companies to repurpose used Chevy Bolt batteries for grid‑scale storage. Tesla has deployed Powerwall systems that can integrate with retired vehicle packs, though the company primarily uses new cells. Startups like B2U Storage Solutions in California have been operating a 25‑MWh facility using second‑life Nissan Leaf batteries to store solar energy and sell it back to the grid during peak hours.

The U.S. Department of Energy’s Vehicle Technologies Office has funded multiple projects to study battery second‑life economics, estimating that the market could reach $4.5 billion by 2030. A 2024 study from the National Renewable Energy Laboratory found that repurposing EV batteries for stationary storage could extend their useful life by 5–10 years, delaying recycling costs and reducing the carbon footprint of the battery lifecycle.

Challenges and opportunities

Despite the promise, challenges remain. Battery health assessment, repackaging, and certification for stationary use require standardized protocols. In the U.S., Underwriters Laboratories (UL) has developed safety standards for second‑life batteries, but adoption is still voluntary. Moreover, warranty and liability issues often deter automakers from encouraging second‑life reuse.

Nonetheless, the trend is accelerating. Automakers including Ford, Nissan, and Renault have launched second‑life pilot projects in Europe, the U.S., and Japan. The approach aligns with circular economy principles, reducing waste while providing affordable energy storage to households and businesses.

Gadkari’s remarks in Nagpur serve as a reminder that the second‑life battery opportunity is global. As EV adoption grows in the U.S.—with over 1.4 million EVs sold in 2024—the volume of retired batteries will surge, creating a supply that could power millions of homes if properly deployed.

Bottom line

The reuse of used EV batteries as home energy storage is no longer a niche concept. With government endorsements, corporate pilots, and technology advancements, the second‑life battery market is poised to become a cornerstone of sustainable energy. Whether in India or the United States, the message is clear: an EV battery’s journey doesn’t end when it leaves the car. It can still light up a home, stabilize a grid, and help drive the clean energy transition forward.