Silver oxide primary batteries

TABLE 12.1 Major Advantages and Disadvantages of Zinc/Silver Oxide Primary Batteries ... 

FIGURE 18.4 Assembly of automatically activated zinc/silver oxide primary battery with tubular coil reservoir. Courtesy of Eagle-Picher Industries.)... 

FIGURE 18.12 Service life of zinc/silver oxide primary batteries. (Courtesy of... 

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. 

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. 

There are two major types of household batteries (a) Primary batteries are those that cannot be reused. They include alkaline/manganese, carbon-zinc, mercuric oxide, zinc-air, silver oxide, and other types of button batteries, (b) Secondary batteries are those that can be reused secondary batteries (rechargeable) include lead-acid, nickel-cadmium, and potentially nickel-hydrogen. 

There are several types of battery we can envisage. A majority of the batteries we meet are classed as primary batteries, i.e. a chemical reaction occurs in both compartments to produce current, but when all the chemicals have been consumed, the battery becomes useless, so we throw it away. In other words, the electrochemical reactions inside the battery are not reversible. The most common primary batteries are the Leclanche cell, as described below, and the silver-oxide battery, found inside most watches and slim-line calculators. 

Mineral wool, asbestos substitute, 3 314t Miniature alkaline primary cells, 3 449 59 cutaway view, 3 449 divalent zinc-silver oxide batteries, 3 454 55... 

Demand pacemakers are very low current devices, requiring only 25-50 jiW for sensing and 60-100 pW for stimulation. In contrast, implanted ventricular defibrillators (Fig. 1.3) must be able to deliver short electric pulses of 25-40 J (e.g. 2 A at 2 V for 10 s) which can shock the heart into normal rhythm, and hence require a much higher rate battery. The most common system is a lithium-silver vanadium oxide cell with a liquid-organic based electrolyte. More than 80 000 such units have been implanted. Implanted drug delivery devices also use lithium primary batteries, as do neurostimulators and bone growth stimulators. 

In Scotland, the cost of domestic mains electricity is 0.0713/kWh (in 1997). A D-size Leclanchd cell, delivering say 5 Wh, currently retails at 0.50. Thus, energy from the primary battery costs I00/kWh - a factor of over 1000 more expensive. For a 150 mWh zinc-silver oxide button cell, retailing at 1.50, the cost of energy is over 10 000/kWh ... 

The primary objective of miniature battery design is to maximize the energy density in a small container. A compromise must be reached, however, since volumetric energy density decreases as cell volume decreases and the dead volume due to containers, seals, etc. becomes increasingly significant. A plot of energy density as a function of total volume is given in Fig. 3.28 for the zinc-mercuric oxide and zinc-silver oxide systems. 

Batteries, lead-acid -zinc-silver oxide [BATTERIES - PRIMARY CELLS] (Vol 3) - [BATTERIES - SECOND ARYCELLS - LEAD-ACID] (Vol 3) -arsenic m [ARSENIC AND ARSENIC ALLOYS] (Vol 3) -barium m [BARIUM] (Vol 3) -use of lead compounds [LEAD COMPOUNDS - LEAD SALTS] (Vol 15)... 

Batteries. Primary, ie, nonrechargeable, batteries containing silver compounds have gained in popularity through use in miniaturized electronic devices. The silver oxide—zinc cell has a cathode of Ag-O or AgO. These cells are characterized by a high eneigy output per unit weight and a fairly... 

Leifer et al. [105]. used Li MAS NMR to study the strucmre of lithiated silver vanadium oxide, Liy4g2V40n, where x = 0.72,2.13, and 5.59. This compound is used in biomedical applications as a primary battery, particularly as the power source for implantable cardiac defibrillators (ICDs). Silver vanadium oxide is a vanadium bronze with semiconducting properties. It has been used successfully as a cathode material in the battery of ICDs due to its high rate capability and its high theoretical capacity (315 mAh/g) to 2 V. Electrochemical and structural studies of the average structure were performed by various authors who concluded that the systems undergoes a multistep reduction mechanism and forms silver metal in the early stage of the overall reaction [106-108]. 

The Zn negative electrode material, or anode, and electrolyte solution are similar to other primary alkaline battery types, like zinc-air and zinc-silver oxide (Zn/ Ag20). Zinc powder is mixed with a gelling agent like polyacrylic acid and a KOH-Zn0-H20 electrolyte. 

Sony Corporation started its battery business in the mid-1970s. Its staple battery products in those days were primary ones, e.g. silver oxide, carbon zinc, alkaline manganese, and primary lithium cells. To adapt Sony s battery business to the above-mentioned trend, the development of novel rechargeable cells was a pressing necessity. 

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