Silver zinc, primary applications

The first practical silver—zinc battery was developed more then 60 years ago. Since then, primary and secondary silver—zinc batteries have attracted a variety of applications due to their high specific energy, proven reliability and safety, and the highest power output per unit weight and volume of all commercially available batteries. However, they find very limited use in commercial applications, because of their high price and limited cycle life. Development of a battery separator which will improve the performance and life of zinc based alkaline cells has been... 

Currently, Yardney is in continuous production of secondary lithium-ion batteries, primary and secondary silver-zinc batteries and primary reserve silver-zinc batteries used on various Department of Defense applications. The primary battery applications include the Navy s Trident IID5 Fleet Ballistic Missile program, the Minuteman III ICBM, and primary power for the MK 21 re-entry vehicle. In 2012, the Trident II missile has achieved 143 successful test launches since 1989—a record unmatched by any other large ballistic missile or space launch vehicle. The most prominent Li-ion batteries made by Yardney have powered the Mars Explorer Rover missions (Spirit, Opportunity, and Curiosity), the USAF B-2 Bomber and Global Hawk aircraft, and the US Navy Advanced SEAL Delivery System (ASDS). One of the future applications for Yardney s Li-ion batteries is NASA s Orion Crew Exploration Vehicle (CEV). 

E. A. Megahed and D. C. Davig, Long life Divalent Silver Oxide-Zinc Primary Cells for Electronic Applications, Power Sources, Vol. 8, Academic, London, 1981. 

The cost of high-performance primary zinc/silver oxide batteries is dependent on the specifications to which they are built and the quantity involved. Manual-type batteries may cost anywhere from 5 to 15 per Watthour remote-activated types will cost about 15 to 20 per Watthour. When the price of silver is high, material cost becomes one of the chief disadvantages of these batteries. There are many applications, however, in which no other technology can meet the high energy density of the zinc/silver oxide primary system. 

As with the primary battery systems, significant performance improvements have been made with the older secondary battery systems, and a number of newer types, such as the silver-zinc, the nickel-zinc, nickel-hydrogen, and lithium ion batteries, and the high-temperature system, have been introduced into commercial use or are under advanced development. Much of the development work on new systems has been supported by the need for high-performance batteries for portable consumer electronic applications and electric vehicles. Figure 22.1 illustrates the advances achieved in and the projections of the performance of rechargeable batteries for portable applications. 

Table 52.1 shows some of the types of primary AHP type silver-zinc batteries supplied by Yardney for various aerospace applications. 

Battery systems of complex design and structure using—at least for one electrode—expensive materials are (for economic reasons) mainly conceived as storage batteries. Primary (and "reserve") versions of the zinc/silver oxide battery [(-) Zn/KOH/AgO (+)] — as a first example—are only used in particular cases where the question of cost is not crucial, e.g., for marine [26-28] and space applications [29]. 

Zinc-silver oxide batteries as primary cells are known both as button cells, e.g., for hearing aids, watches, or cameras, and for military applications, usually as reserve batteries. Since the latter after activation have only a very short life (a few seconds to some minutes), a separation by cellulo-sic paper is generally sufficient. 

The vendor states that MBS stabihzes heavy metals in soil, slndges, slag, ash, baghonse dnst, and sediment. Among the heavy metals treatable by the MBS process are arsenic, cad-minm, chrominm, copper, lead, mercnry, nickel, silver, and zinc. MBS technology is applicable in the following indnstries primary and secondary smelters, battery mannfactnrers and recyclers, ferrons and nonferrons fonndries, mnnicipal solid waste incinerators, anto and metal scrap recyclers, electronic mannfactnrers, electroplaters, ceramic prodnct mannfactnrers, and mineral refiners and processors. 

Because unalloyed magnesium is not used extensively for structural applications, it is the corrosion resistance of magnesium alloys that is of primary interest. To enhance strength and resistance to corrosion, magnesium is alloyed with aluminum, lithium, zinc, rhenium, thorium, and silver, with minor additions of cerium, manganese, and zirconium sometimes being used as well. 

The intracellular localization of stress proteins is problematic for the evaluation of the response in humans. Because the cells for the assay of stress proteins are not readily available through noninvasive procedures, the application of this response to human monitoring is limited. Recently, however, enhanced synthesis of stress proteins was demonstrated in primary cultures of human lymphocytes exposed to several metals (Yamada and Koizumi 1993). The specificity of the response was dependent on the metal to which the cultures were exposed. For example, cadmium and zinc induced both hsp70 and MT, while cobalt and triphenyltin induced only hsp70. Conversely, copper, mercury, nickel, and silver all induced synthesis of MT, but not of hsp70. Enhanced synthesis of stress proteins has also been demonstrated in vivo in lymphocytes and spleen cells excised from mice exposed to hyperthermia (Rodenhiser et al. 1985). 

A recent compilation of suppliers of primary monovalent silver oxide-zinc and divalant silver oxide-zinc cells for watch and calculator applications is given below. 

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