Primary batteries silver oxide cells

Primary Battery Design, Fig. 8 Cross section of a silver oxide cell... 

Zinc/Silver oxide valency 1 or 2 1.55 350 650 Primary battery in button cell design... 

The primary zinc/silver oxide batteries are manufactured mainly in the button cell configuration in a wide range of sizes from 5 to 250 mAh. Most of these batteries are now prepared from the monovalent silver oxide (Ag20). 

The performance advantages of several types of lithium batteries compared with conventional primary and secondary batteries, are shown in Secs. 6.4 and 7.3. The advantage of the lithium cell is shown graphically in Figs. 7.2 to 7.9, which compare the performance of the various primary cells. Only the zinc/air, zinc/mercuric oxide, and zinc/silver oxide cells, which are noted for their high energy density, approach the capability of the lithium systems at 20°C. The zinc/air cell, however, is very sensitive to atmospheric conditions the others do not compare as favorably on a specific energy basis nor at lower temperatures. 

The Japanese Standards Association issues Standard J15 8501 Dry Cells and Batteries, J15 8508 Mercury Cells and Batteries, J15 8509 Alkaline-Manganese Dioxide Cells and Batteries, J15 8510 Silver Oxide Cells and Batteries, and J15 8511 Alkaline Primary Cells and Batteries. All are available through Japanese Embassies or direct from the Japanese Standards Association, 1-24 Atasak4 Chome, Minato-ku, Tokyo, Japan. 

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 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... 

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. 

Regeneration of primary cells is generally not advisable. There is a danger of an augmented inner pressure which can lead to a leakage or explosion. Regeneration should especially not be taken into consideration with mercury oxide, alkaline manganese, and silver oxide batteries due to the mentioned risk of explosion. 

The more familiar types of primary alkaline systems are the zinc/manganese dioxide, zinc/ mercuric oxide, and zinc/silver oxide batteries. These, typically, use potassium or sodium hydroxides, in concentrations from 25 to 40% hy weight, as the electrolyte, which functions primarily as an ionic conductor and is not consumed in the discharge process. In simple form, the overall discharge reaction for these metal oxide cells can be stated as... 

The weight and size of a silver-zinc battery or cell is less than half that of a lead-aeid or niekel-cadmium type of similar capaeity. The silver oxide-alkaline zinc (AgjO KOH Zn) primary battery is a major contribution to miniature power sourees, and is well suited for hearing-aids, instruments, photoelecti ic exposure devices, eleetronie watehes and as referenee voltage sources. 

Other alkaline primary cells couple zinc with oxides of mercury or silver and some even use atmospheric oxygen (zinc—air cell). Frequendy, zinc powder is used in the fabrication of batteries because of its high surface area. Secondary (rechargeable) cells with zinc anodes under development are the alkaline zinc—nickel oxide and zinc—chlorine (see Batteries). 

Batteries contain several voltaic cells in series and are classified as primary (e.g., alkaline, mercury, and silver), secondary (e.g., lead-acid, nickel-metal hydride, and lithium-ion), or fuel cell. Supplying electricity to a rechargeable (secondary) battery reverses the redox reaction, forming more reactant for further use. Fuel cells generate a current through the controlled oxidation of a fuel such as H2. 

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