RePurpose Energy

RePurpose Energy is a clean-tech startup that’s tackling a growing problem: what to do with the massive wave of used electric vehicle (EV) batteries.

Founded in 2018 out of research at the University of California, Davis, the company aims to give these batteries a “second life” by turning them into energy-storage systems for buildings, businesses, and even the power grid.

RePurpose sits at the intersection of two major trends — electric vehicles and renewable energy. As EV adoption rises, so does the number of batteries reaching the end of their useful life in cars. But perhaps surprisingly, these batteries often retain around 70% of their capacity, making them perfectly usable for stationary energy storage.

That’s where RePurpose comes in. Its core product is a “second-life” battery system built from retired EV batteries. Using proprietary technology, including machine learning, RePurpose rapidly tests used batteries, determines their remaining health, and reassembles them into reliable storage units. These systems can then store electricity — often from solar panels — and release it when needed, such as during peak demand or power outages.

RePurpose generates revenue by selling its battery-storage systems to commercial, industrial, and utility-scale customers. It also offers battery testing and related services, which help partners evaluate and reuse their own battery supply. In some cases, the company is also involved in broader energy projects, like microgrids that combine solar power with second-life batteries.

Energy storage is a critical piece of the renewable-energy puzzle, especially as solar and wind power become more widespread. At the same time, the U.S. alone is expected to generate over 150,000 tons of retired EV batteries by the end of the decade. RePurpose is positioning itself as a key player in building a “circular economy” around these batteries — extending their lifespan while reducing waste and the need for new raw materials.

RePurpose delivered its first commercial-scale system to Nissan North America in 2024. It has ongoing partnerships and pilot deployments, including systems supporting solar installations and critical infrastructure. It has also secured more than $9.9 million in non-dilutive grant funding from sources like the U.S. Department of Energy and the California Energy Commission.

One particularly important milestone: RePurpose Energy became the first U.S.-based company to achieve UL 1974 certification for repurposing EV batteries — a key safety and quality benchmark that could help accelerate adoption.

Overall, RePurpose is building infrastructure for a future where batteries don’t just get recycled, they get reused, unlocking more value from every EV produced.

Team Background

Jae Wan Park - Chief Executive Officer

Before launching RePurpose Energy, Jae was a professor of Mechanical and Aerospace Engineering at the University of California, Davis. There, he spent years leading research on renewable energy systems, battery diagnostics, and energy storage technologies—work that ultimately became the foundation for the company.

Earlier in his career, he built his expertise in advanced energy systems and engineering, focusing on how to integrate renewables into the grid more efficiently. His academic and technical background has made him a key figure in bridging cutting-edge research with real-world commercial applications.

Jae earned his Bachelor's of Science in 1997, Master's of Science in 1999, and Ph.D. in 2005, all from Pohang University of Science and Technology in South Korea. After his Ph.D., he completed postdoctoral research and lecturing at the University of Waterloo in Canada before joining the UC Davis faculty.

Joe Lacap - Co-Founder & CTO

Prior to co-founding the company, Joe was deeply involved in research & development at UC Davis, where he worked on battery management systems and energy storage technologies. His work focused on evaluating battery health and performance — critical capabilities for safely repurposing EV batteries at scale.

Earlier in his career, he developed expertise in electrical engineering and energy systems, helping translate complex battery science into practical, deployable products. At RePurpose Energy, he plays a central role in turning second-life batteries into reliable commercial systems.

Joe completed a Ph.D. in Mechanical and Aeronautical Engineering at the University of California, Davis in 2021. Prior to that, he earned a Bachelor's of Science in Physics from Beloit College.

Ryan Barr - Co-Founder & COO

Before starting the company, Ryan worked as a management consultant for electric utilities in the Midwest. During that time, he gained firsthand exposure to how slowly traditional-energy systems were adapting to renewable technologies — a realization that pushed him toward entrepreneurship.

He later attended graduate school at UC Davis, studying energy systems with a focus on how storage can enable greater use of renewable power. It was there that he connected with Jae Wan and the underlying battery research that would eventually become RePurpose Energy.

Ryan holds a Master’s of Science in Energy Systems from the University of California, Davis, and a Bachelor’s of Science in General Engineering from the University of Illinois at Urbana Champaign.

Co-Investors