Lead-acid batteries are currently the least expensive option for use in hybrid electric vehicles. The battery selection process for use in hybrid electric vehicles is complicated due to the limited use of these vehicles. Considerable data exists for the use of lead-acid batteries for other purposes. Unfortunately, much of this data is not directly applicable when these batteries are to be used in hybrid electric vehicles. Currently, there exists a wide variation in the type and format of battery data that is provided by the manufacturers. A comprehensive survey of deep cycle lead-acid batteries was conducted. Batteries were compared using manufacturers published data. To provide a consistent basis for comparison, various performance parameters-energy capacity, capacity, weight, and volume- were normalized with respect to both weight and volume. Additionally, all data was normalized to reflect three hour discharge rates. The battery selection process is then described in detail. Finally, recommendations are presented for the type and format of data that, if provided by the manufacturers, would greatly assist the hybrid electric vehicle battery selection process.