The advanced Battery Business unit of Johnson Controls, Inc. (JCI) is developing the Zinc/Bromine Battery for electric vehicle applications. The battery's potential for good energy density, low manufacturing cost, and long life make it a particularly attractive candidate. Other advantages include ambient temperature operation, a modular design which facilitates design flexibility, and minimal maintenance.In December of 1986, JCI was awarded a cost-share contract from the Department of Energy. Its main objectives are: (1) to continue research and development of the Zinc/Bromine Battery core technology, and (2) to conduct the necessary battery engineering and testing to develop the battery for a proof-of-concept Zinc/Bromine electric van battery. The design specifications for the final contract deliverable battery correspond to application in the Ford ETX-II van. Advances in the core technology, including electrode substrate, separator, cathode activation layer, and electrolyte, have significantly improved the systems's life and performance capabilities.