Executive Team

Mr. Stepien is Amprius’ Chief Executive Officer and has served as a director on the Amprius Board since May 2025. He brings more than 3 decades of leadership experience in energy storage, advanced manufacturing and technology innovation. Prior to joining Amprius, Tom served as CEO of South 8 Technologies, where he led the commercialization of liquefied gas electrolytes for lithium-ion batteries. Previously, he was an Operating Partner at KCK Group, a private equity firm focused on industrial technologies; co-founded and led Primus Power, a long-duration stationary energy storage company; and spent over a decade at Applied Materials, where he held roles of increasing responsibility in software, operations and general management.

Tom earned bachelor’s and master’s degrees in mechanical engineering from MIT. He is an Independent Director of Euro Manganese (TSX-V and ASX: EMN), where he chairs the Sustainability Committee and is a member of the Technology Committee. He attended Stanford Law School's Directors College, an executive program on board responsibilities, corporate governance and legal frameworks. Tom is passionate about teamwork, customer success and lifelong learning.

Mr. Rodriguez has served as Amprius’ Chief Financial Officer since October 2025. He most recently served as Chief Financial Officer and Treasurer of Aspen Aerogels, Inc., a publicly traded advanced materials company, from April 2022 until joining Amprius, and previously as Aspen’s Chief Strategy Officer from November 2021 to April 2022. From February 2019 to November 2021, he was a Corporate Strategy Director at Aptiv, a global automotive technology company, where he led the establishment of the Vehicle Electrification Systems group, among other value-adding initiatives. From April 2010 to February 2019, he held finance, planning, and operational leadership roles at ClearMotion; General Motors’ OnStar division (in-vehicle safety and security); Amazon; and Fiat Chrysler Automobiles (now Stellantis). Earlier in his career, Mr. Rodriguez was an investment banker at Lazard, a financial advisory firm, focusing on automotive mergers and acquisitions and restructuring advisory services. He received his Bachelor of Science degree in Mechanical Engineering from General Motors Institute / Kettering University while working at Magna International and holds an MBA from Harvard Business School.

Dr. Stefan has served as Amprius’ Chief Technology Officer since August 2015. Dr. Stefan is a recognized expert in electrochemistry and energy storage and leads Amprius’ scientific research and development activities for advancing lithium ion cell performance. Dr. Stefan has also served as a Senior Scientist at Amprius, Inc. since November 2009 and as Director of Battery Technology since November 2012. Prior to joining Amprius, Inc., Dr. Stefan was a Scientist Electrochemist at Nanosys Inc. Dr. Stefan holds a Ph.D. in Chemistry from Case Western Reserve University, a M.S. degree in Electrochemistry and Analytical Chemistry from Babes-Bolyai University, and a B.S. degree in Chemistry from Babes-Bolyai University.

Ronnie Tao is Chief Business Officer at Amprius Technologies, where he leads the company's global commercial organization, including business development and customer partnerships for its silicon-anode batteries. He has more than 15 years of experience in the battery industry across Asia, Europe, and North America.

Before Amprius, Ronnie led North American business development at Highpower International and held senior commercial roles at Sony/Murata and Amazon Lab126, where he worked on battery programs spanning wearables to automotive applications. At Amprius, he focuses on expanding the company's presence in aviation, defense, mobility, and consumer applications.

Anne Torricelli is Vice President of Sales at Amprius Technologies, where she leads global sales and business development for the company's silicon-anode batteries. She brings nearly 20 years of international commercial experience, including more than 12 years commercializing battery technologies across grid-scale energy storage, aerospace, defense, and electric mobility, with a track record of closing agreements ranging from $5M to over $100M.

Before Amprius, Anne served as Managing Director of Energy Storage Solutions at Gotion, a top-three global LFP battery manufacturer, where she managed a multi-billion-dollar opportunity pipeline and structured multi-year supply agreements for manufacturing scale-up. Earlier, as Head of Business Development at Cuberg (a Northvolt company), she led global commercialization of lithium-metal battery technology and secured the company's first strategic engagement with Safran. She has also held commercial leadership roles at Honeywell, Samsung SDI, and Trina Solar, spanning lithium-ion, lithium-metal, flow, and long-duration energy storage across the renewable energy, utility, and mobility markets.

Anne holds honors and standard Bachelor of Business Administration degrees in international business from Montpellier Business School in France and La Trobe University in Australia. A dual U.S. and French citizen who has lived and worked across France, Italy, China, and the United States, she speaks five languages.

Ms. Jiang brings more than a decade of experience in the legal industry to Amprius. For seven years, she was an associate at Wilson Sonsini Goodrich and Rosati, counseling both public and private companies on corporate and transactional legal proceedings. Prior to that, she was an associate at Davis Polk and Wardell, serving as counsel for various public offerings and capital markets deals. She received her J.D. from the University of Michigan Law School, graduating cum laude.

Mr. Huie has served as Amprius’ Vice President of Infrastructure since September 2022, leading the Company’s high-volume manufacturing initiative as it begins to scale its production capacity. He focuses on factory planning, facility development, and regulatory compliance. Prior to joining Amprius, Mr. Huie served as the Director of Facilities for Panasonic Energy of North America at Tesla’s first Gigafactory in Sparks, NV. He was instrumental in the site selection and development plans of Panasonic Energy’s Gigafactory in De Soto, Kansas aiming to advance the EV industry in the US. Previously Mr. Huie has held different senior management positions for expansions of critical infrastructures at The Jackson Laboratory, Xyratex International, Jacobs Engineering Group, Optisolar, and NEC Electronics America. Mr. Huie is a Certified Facility Manager and holds a B.S. degree in Mechanical Engineering from CSU, Chico.