Don Stewart was named president of Toyota North Carolina and region seven group vice president in May 2025, following a three-year tenure as plant operations lead and vice president of manufacturing at Toyota’s newest plant in North America.

Toyota North Carolina is the company’s first in-house battery manufacturing plant outside of Japan. As president, Stewart oversees the construction and start of production of the $13.9 billion investment. Once fully operational, the plant will employ approximately 5,100 North Carolinians and feature 14 production lines that will deliver lithium-ion batteries for hybrid electric, plug-in hybrid electric, and battery electric vehicles.

Under his leadership, Stewart oversees all areas of site construction and battery manufacturing, including the development of innovative workforce training initiatives, emergency preparedness planning and community response, team member safety and security, onsite fire brigade, production, engineering, human resources, and maintenance.

Stewart joined Toyota in 1997 as a maintenance group leader at Toyota Motor Manufacturing West Virginia (TMMWV) in Buffalo, West Virginia. From there, he was promoted to maintenance manager, the first of many promotions and assignments he would undertake in his 20-year career at TMMWV. In 2018, Stewart accepted a dispatch position with Hino Motor Manufacturing as Vice President of Manufacturing Support. He returned to Toyota in 2021 as a vice president of production engineering, overseeing the powertrain division.

Stewart is an alumnus of West Virginia University Institute of Technology, where he received bachelor’s degrees in civil and mechanical engineering. In 2019, he earned a Master of Business Administration (MBA) from the University of Charleston, and in 2025, Stewart graduated from the University of Wisconsin with a master’s degree in engineering. Stewart is a veteran of the United States Army, having served in the Ranger Battalion, is a graduate of the U.S. Army’s Sniper School, and a former US Army Sniper School instructor. He currently serves on the board of the Army Sniper Association and the North Carolina Energy Policy Task Force.

Stewart resides with his wife, Julie, in Apex, and his son, Liam, is a maintenance technician at Toyota West Virginia.

Dr. Zhengming (John) Zhang is the Chief Technology Officer and Chief Science Officer of Celgard/Polypore (Asahi Kasei Group) and a globally recognized leader in lithium-ion battery safety. His career has been devoted to understanding and mitigating failure mechanisms in high-energy batteries—one of the most critical challenges in modern energy-storage technology.

Dr. Zhang established the Internal Spot Shorting–Induced Thermal Runaway Mechanism (ISSITRM), demonstrating that most catastrophic lithium-ion battery failures originate from localized internal short circuits in the anode that propagate, rather than from uniform bulk heating of cell components. To address this dominant failure mode, he invented the Ceramic-Coated Separator (CCS), a transformative technology that suppresses short-circuit propagation and dramatically improves both safety and performance. CCS has since been adopted across the global battery industry and is now a cornerstone of high-energy lithium-ion cell design.

Dr. Zhang also led the cell-level working groups for IEEE P1625 and IEEE P1725, establishing the first production-level safety standards for lithium-ion batteries through collaboration with scientists, engineers, industry leaders, and legal experts worldwide. Together, CCS and these IEEE standards have improved real-world battery safety by five-to-six orders of magnitude, enabling the widespread and reliable use of lithium-ion batteries in consumer electronics, electric vehicles, and energy-storage systems.

Dr. Zhang has organized more than 60 international battery conferences, authored over 300 scientific publications, holds more than 260 patents, and contributed to four book chapters. His honors include the 2024 International Battery Association (IBA) Technology Award and the 2026 NAATBatt Lifetime Achievement Award, joining a distinguished group of prior recipients that includes Nobel Laureates John B. Goodenough, M. Stanley Whittingham, and Akira Yoshino, as well as CATL founder Robin Zeng.

Tien Duong currently manages the Advanced Battery Materials Research (BMR) Program and the Battery500 Consortium at the Vehicle Technologies Office (VTO). The BMR program conducts battery research with a strong emphasis on developing, modeling, and conducting diagnostics for new materials. These materials are to be utilized in future battery technologies and could be ready for commercialization in the next ten to fifteen years. The Battery500 Consortium works toward demonstrating a battery cell having 500 Wh/kg of specific energy and 1,000 cycles life. Candidate chemistries include those utilizing metallic lithium as the negative electrode with either a high-nickel NMC material or sulfur as the positive electrode and a compatible electrolyte. Altogether, Mr. Duong supervises a complex, integrated materials R&D portfolio of over 80 research projects with an annual budget of over $40 million. 

Mr. Duong has been an integral part of the Energy Storage R&D effort within the Vehicle Technologies Office for almost 30 years and served in various positions including as Manager of the Energy Storage R&D Team (1999–2003) and Team Lead for the Hybrid and Electric Systems Team (2004–2008). Before joining the U. S. Department of Energy, Mr. Duong was a Senior Electrical Engineer at the US Army Belvoir R&D and Engineering Center at Fort Belvoir, Virginia. 

Mr. Duong has also served as a member of the Technical Advisory and Management Committees of the United States Advanced Battery Consortium (USABC) formed in 1992 under a cooperative agreement between the US Department of Energy and the three U.S. automotive manufacturers (General Motors, Ford, and Chrysler) to jointly develop advanced batteries for electric vehicles. 

Mr. Duong studied Chemistry at the University of Science in Ho Chi Minh city (Saigon), Vietnam before immigrating to the United States in 1979. He holds a B.S. in Electrical Engineering and an M.S. in Civil Engineering (Environmental Sciences), both from Virginia Polytechnic Institute. Mr. Duong also holds a Professional Engineer (PE) license in the State of Virginia.