Ergenics is developing a low pressure high power rechargeable battery for electric vehicles and other large battery applications. The Hy-Stor(TM) battery couples a bipolar nickel-hydrogen electrochemical system with the high energy storage density of metal hydride technology. In addition to its long cycle life, high specific power, and energy density, this battery offers safety and economic advantages over other rechargeable batteries. Results from preliminary testing of the first Hy-Stor(TM) battery are presented.