EOS Energy Enterprises, Inc. (NASDAQ: EOSE) has announced significant changes in its leadership. Russ Stidolph, who has been the non-executive chair since April 2018, is stepping down from the board of directors, effective December 31, 2025. Stidolph's firm, AltEnergy, LLC, has been a lead investor in EOS for the past eleven years. The board has appointed Joseph Nigro to succeed Stidolph as non-executive chair, effective January 1, 2026.
Stidolph has been instrumental in guiding EOS from an early-stage research and development company to a scaled leader in stationary energy storage. Under his leadership, EOS successfully deployed over 5 GWh of operations in the field.
Joseph Nigro, who joined the EOS board in early 2025, brings more than three decades of global energy, utility, and infrastructure experience to the company. Nigro has held numerous senior leadership roles across the energy industry, including chief financial officer of Exelon Corporation and CEO of Constellation, a former Exelon operating company.
Since joining the board, Nigro has played a critical role in shaping the company’s strategic direction during a period of rapid commercial momentum and U.S. manufacturing expansion. His expertise across energy markets, finance, and large-scale operational execution makes him the right leader to guide the board at this pivotal stage.
EOS CEO Joe Mastrangelo expressed gratitude for Stidolph's leadership and highlighted his instrumental role in the company's journey. Mastrangelo also emphasized the strategic vision and industry perspective that Nigro brings, stating that it will provide invaluable guidance to the leadership team and shareholders as the company continues to scale production and meet growing demand for flexible, American-made long-duration storage.
EOS Energy Enterprises is known for its innovative zinc-based battery energy storage systems (BESS) manufactured in the United States. The company's BESS features the innovative Znyth™ technology, which is a proven chemistry with readily available non-precious earth components. This technology is considered a safe, non-flammable, secure, stable, and scalable alternative to conventional lithium-ion technology.
With these changes in leadership, EOS Energy Enterprises is poised to enter its next phase of operational execution and market expansion as it continues to play a critical role in the future energy mix, providing flexible and reliable long-duration storage solutions. As a result of these announcements, the company's shares have moved 6.12% on the market, and are now trading at a price of $13.0632. For the full picture, make sure to review Eos Energy Enterprises's 8-K report.
