Tests were completed on a 8 Ah, 12 V silver-iron experimental battery designed for the performance requirements of a radio pack. Common operating constraints for communications batteries, such as maintenance-free operation, were considered in the design. The need for high capacity, rechargeability, and cyclic stability was assumed. Results show that the silver-iron battery can be operated maintenance-free for over 20 cycles with negligible degradation in capacity or voltage. During operation the battery was tilted and inverted but no free electrolyte was observed. Any decline in capacity past 20 cycles of operation was immediately recovered with the addition of water at cycle 25. The data indicate that careful control of the charge and discharge procedures could extend maintenance-free operation beyond 20 cycles. The discussion concludes with a review of several design modifications which are underway to eliminate the need for maintenance entirely

A seawater-activated power cell for low power, long life undersea missions is under development. The cathode uses dissolved oxygen in seawater as a reactant. The anode is a selected magnesium alloy which limits self discharge and extends cell life. The cell displays an open circuit voltage of about 1.6 volts. Under a load that would be equivalent to that required for a typical one year mission, eg., 2 to 3 watts, this power cell displays a working potential of 1.3 to 1.4 volts and has a total weight of about 32 kg. No pressure compensation is necessary since the structure is totally open to the seawater. Tests to date in selected ocean environments show that the cell operates well in low salinity water and in oxygen-depleted areas where other systems generally fail. Ocean tests have also shown that this power source can provide in excess of 700 Wh/kg for months. It has also been shown to operate both under ice and in fresh water

A study was undertaken to determine compatability requirements of the Westinghouse iron-air battery propulsion system when utilized in various commuter electric vehicles. Both battery and vehicle size and weight parameters were adjusted to satisfy several defined vehicle missions. 6 refs.

An iron-active electrode is provided for secondary cells or batteries with spaced apart perforated and expanded nickel sheets the interstices of which are filled with a powder prepared by reducing a ferric oxide powder in hydrogen at about 700/sup 0/C to an aglomerated iron powder. The iron powder is separated and surface-oxidized by treatment with deionized water followed by drying at temperatures from ambient to about 100/sup 0/C. A pore former such as urea having a minimum particle size of about 83 microns is added and the mixture die pressed with the current collectors and sintered in hydrogen between about 700/sup 0/C and about 900/sup 0/C to produce electrodes having a density between about 15% and about 35% of the theoretical density of iron.

High-temperature (1000/sup 0/C) solid-oxide cells were employed to electrolyze water vapor. System energy efficiency of 45%, compared to conventional electrolysis at approx. 30% maximum could be possible. Stable levels of resistance and diffusion polarization were observed after approximately 450 hours of continuous testing. Approximately 100% coulombic efficiency was measured. Water vapor dissociation at a nominal 1 volt at > 300 A/sq. ft. can be expected with heat sources near 1000/sup 0/C. Lower-temperature heat sources may be employed as well, at a commensurately higher voltage. Future planned studies would evaluate design/performance tradeoffs and cost/economic advantages derived from interfacing with various primary resources, such as solar thermal as well as coal conversion systems. 16 references, 5 figures, 3 tables.