Batteries play a fundamental role in energy storage, and currently nearly 99 million lead acid batteries are manufactured each year. This past Wednesday, U.S. Environmental Protection Agency (EPA) issued a proposed rule in the Federal Register relating to air emissions controls for lead acid battery manufacturers. Highlights of the proposed rule are more stringent lead emission limits for grid casting, paste mixing, and lead reclamation operations under both the National Emissions Standards for Hazardous Air Pollutants (NESHAP) (for new and existing sources) and new New Source Performance Standards (NSPS) for lead acid battery facilities that begin construction, reconstruction, or modification after February 23, 2022.