Hybrid Electric Vehicles (HEVs) have several potential advantages over traditional internal combustion engine (ICE) vehicles. They promise higher fuel economy and lower emissions without sacrificing vehicle performance and range. They can also take advantage of the existing fuel delivery infrastructure which may facilitate their acceptance by the consumer. High performance electrochemical battery systems are the most promising candidates for providing peak power for HEVs in the near future. However, the specific requirements these batteries must meet (higher specific power, good high rate charge acceptance, low self discharge) are much more stringent than for any other application. This paper summarizes general test requirements and procedures used in the development and characterization of battery packs and management system for hybrid electric vehicles. A comparison of the capabilities of existing test equipment is also given.