A New Stabilized Nickel-Zinc Battery System for Electric Vehicle Applications 830287
A substantially modified chemistry for the nickel oxide-zinc battery system has been discovered and developed to stabilize the zinc anode and substantially reduce the well-known problems of dendrite shorting, shape change and plate densification. As is well known, these phenomenon have been basically responsible for the poor cycle life (typical 100 -200) normally experienced in this battery system.
The introduction of the new chemistry has resulted in stabilization of the performance of the zinc anode without adversely affecting the nickel electrode. The result has been a major enhancement of the cycle life capability. In tests conducted on 15, 60 and 225 AH capacity, nickel-zinc cells, control groups were used for the sake of comparison. Most tests were conducted using a 3-hour rate of discharge and an 80% depth with a 9-hour recharge rate. Cycle life enhancement obtained range by a factor of 2 to 4 times with capacity retentions over 60% compared to the true original capacity.
A cycle life of at least 500 is shown to be necessary for economic use of the nickel-zinc battery in electric vehicle applications. The new chemistry stabilized battery system provides the opportunity to achieve and exceed this goal on a practical level in full size 15 - 40 KWH batteries.