DEVELOPMENT OF ZINC/AIR 24 VOLT, 48 AMPERE-HOUR STANDARD LINE BATTERY SYSTEM.

Abstract : The report covers the work performed toward the development of a 48 ampere-hour zinc/air battery system conforming to the Electronics Command Technical Requirement SCL 6895 amendment 1 dated April 20, 1967. This requirement called for the development of a versatile battery system capable of delivering 48 ampere-hours within a weight restriction of 15 pounds and conforming to the standard line battery cross section. The standard line battery cross section (length 12 in, width 4 in, height 9 in) represents a size designation for a new military family of batteries. Batteries have been designed, fabricated and tested. The battery weight is 14.8 pounds and the system has a maximum current capability of 10 amperes. This system has been tested on three duty cycles at various ambient temperatures (0F, 70F and 125F). These tests have indicated that full capacity can be obtained at room temperature on a battery having up to 150 hours of operation. Repeated cycling of the battery beyond this point results in an increased loss of water evaporation from the cells and a lowering of the electrochemical performance. This loss of water can be replenished by a simple water addition to all cells and full capacity is obtained. Re-addition of water also has the advantage that full capacity can be delivered at the high temperature point (+125F). Life studies have been performed at LML and indicate that a battery life in excess of 600 hours is obtainable at the present time. (Author)