Advances in Ni-MH battery performance

The V-Ti-Zr-Ni-Cr alloy system has been developed for Ni-MH batteries. The authors discuss alloy characteristics, implications for cell construction, and advances in cycle life performance for a variety of practical conditions. These alloys have high hydrogen storage capacity, low cost, excellent mechanical and chemical properties, and are easy to manufacture. General performance characteristics of these Ni-MH batteries allow drop-in replacement for Ni-Cd batteries. Cycle life has been established at over 400 cycles under aggressive 100% depth of discharge conditions and under several test conditions emphasizing overcharge and deep discharge. Advanced cell designs have achieved over 700 cycles under 100% DOD conditions, with projections that 1000 cycles may be possible