Amprius Technologies, Inc. (NYSE: AMPX), a developer of next-generation lithium-ion batteries based on its silicon anode platform, has announced a planned leadership transition. The company’s Board of Directors has appointed President Tom Stepien as Chief Executive Officer, effective January 1, 2026.
The transition follows the planned retirement of current CEO and founder Dr. Kang Sun, who will step down at the end of 2025. Dr. Sun will continue to serve on Amprius’ Board of Directors and remain involved as an Executive Advisor, providing strategic guidance as the company advances its technology and commercial roadmap.
Founded in 2015, Amprius has focused on developing and commercializing silicon anode battery technology designed to deliver higher energy density and improved performance compared to conventional lithium-ion batteries. Under Dr. Sun’s leadership, the company progressed from early-stage research to commercial deployment, achieving performance milestones that have positioned Amprius as a technology innovator in aerospace, electric mobility, and other high-performance energy storage applications.
Reflecting on his transition, Dr. Sun said, “Leading Amprius Technologies has been one of the most rewarding experiences of my career. I am proud of what our team has accomplished in advancing silicon anode technology from the lab to commercial deployment, and I look forward to continuing to support the company in my ongoing roles.”
Tom Stepien joined Amprius in May 2025 as President and has since played a role in strengthening operations, expanding customer engagement, and supporting the company’s growth strategy. He brings more than 35 years of leadership experience across innovation-driven and customer-focused technology companies.
Prior to joining Amprius, Stepien served as CEO of South 8 Technologies, where he led the development of advanced electrolyte solutions for lithium-ion batteries. He also co-founded and led Primus Power, a company focused on long-duration stationary energy storage, and served as an Operating Partner at KCK Group, a private equity firm specializing in industrial technologies. Earlier in his career, he held leadership roles at Applied Materials.
Commenting on his appointment, Stepien said, “I am honored to step into the role of CEO and build on the strong foundation Kang and the team have established. Amprius’ silicon anode technology continues to set new performance standards, and I look forward to leading the company through its next phase of growth and innovation.”
Don Dixon, Chairman of the Board, thanked Dr. Sun for his leadership and said the Board is confident that Stepien’s experience and industry knowledge position him well to guide Amprius as demand for advanced battery technologies continues to grow.
