Zinc-Air

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). 

Parameter Garb on—2inc (Zn/Mn O2) Alkalinemanganese dioxide (Zn—Mn02) Mercuricoxide(Z n-HgO) Silveroxide (Zn—A Zinc—air (Zn—02 )... 

Fig. 21. Retention of discharge capacity of miniature zinc—air battery having an unopened sealed cell after storage at 20°C (-) projected data (21).

Fig. 22. Effect of temperature on discharge efficiency of miniature zinc—air batteries (21).

Fig. 26. Schematic diagram of the separate charge and discharge modules of the Gnnerale d ElectricitH circulating zinc—air battery (91).

A. L. Almerini and S. J. Bartosh, "Simulated Field Tests on Zinc—Air Batteries," Proceedings of the 26th Power Sources Symposium, Adantic City, N.J.,... 

Leclanche or dry cell Alkaline Cell Silver-Zinc Reuben Cell Zinc-Air Fuel Cell Lithium Iodine Lithium-Sulfur Dioxide Lithium-Thionyl Chloride Lithium-Manganese Dioxide Lithium-Carbon Monofluoride... 

In compounds, the important oxidation numbers of Cr are +2, +3, and +6. In all of these states the chromium ions are colored and, in fact, the element got its name from this property (ichroma is the Greek word for color). The +2 state is not frequently encountered but it can be made quite easily as the beautiful blue chromous ion in solution by dripping a solution containing CrM over metallic zinc. Air has to be excluded since O rapidly converts Cr1-5 back into Cr. ... 

The capacity of single-use alkaline zinc-air cells is twice that of manganese dioxide-zinc cells. They cost less than silver oxide-Zn batteries or Li batteries. The best example of consumer usage is the hearing-aid button cell. In sealed condition it can be... 

Soon it became evident that the zinc anode, working in both cases under capacity-limiting conditions, causes severe troubles too. Whereas in the zinc/air system the anode automatically limits the discharge (because access to oxygen from the air is practically unlimited), the anode limitation in zinc/manganese dioxide cells has another reason Kordesch and co-workers... 

The Zinc-air battery is more expensive than the dry cell and deteriorates relatively quickly once it is exposed to air. High capacity and a cell potential that does not vary with use offset these disadvantages. Like the dry cell, a zinc-air battery uses zinc for the anode reaction. Uniquely among batteries in common use, this battery relies on molecular oxygen from the atmosphere for its cathode reaction. 

In a zinc-air battery, zinc is oxidized and molecular oxygen is reduced, but no net change occurs in the concentrations of any species in solution. The migration of OH through the zinc paste carries current and maintains a uniform concentration. 

C19-0082. A digital watch draws 0.20 mA of current provided by a zinc-air battery, whose net reaction is... 

C19-0089. Explain why zinc-air batteries find extensive use for cameras and pacemakers but are not used to start automobiles. 

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. 

Mercuric oxide batteries are being gradually replaced by new technologies such as silver oxide and zinc-air button batteries that contain less mercury. 

D—Leclanche Zinc anode Carbon, silver chloride, and air Primary and secondary Zinc—air batteries, carbon—zinc batteries, and silver chloride-zinc batteries... 

The second and the third papers of this chapter were contributed by Bulgaria s National Academy of Sciences distinguished developers, Dr. A. Kaisheva and Professor I. Iliev. The two papers address magnesium-air and zinc-air chemistries, respectively. Concepts of mechanical recharging, new non-KOH based electrolytes, and the role of carbon materials in cell design have been thoroughly studied. Authors have reduced to practice their many developments. Systems created work(ed) in many specialty applications. 

Zinc is commonly used as an anode in metal-air batteries. Zinc-air batteries are commercially available and used as power supply for navigation buoys, communication systems, hearing aids, and etc. [2], Mechanically rechargeable Zn-air batteries are developed recently for traction [3],... 

Iliev I., Kaisheva A., Stoynov Z. Pauling H.J, Mechanically rechargeable Zinc-air cells, Proceedings of the 3th International Battery Recycling Congress, July 2 - 4, 1997, Noordwijk Aan Zee, the Netherlands. 

The theoretical data [1] shows that Li and Ca possess very high energy density (13172 and 4560 Ah/kg respectively) but these metals are not suitable to be used as anodes because of their instability in aqueous electrolytes. The theoretical energy densities of Mg and A1 are also high (6846 Wh/kg and 8212 Wh/kg). It is shown that some alloys of Mg and A1 can be successfully used as anodes, especially in metal-air cells with neutral electrolytes. The theoretical energy density of Zn is much lower than that of Li and Ca, but the self-discharge of Zn can be effectively suppressed by the use of suitable inhibitors. That s why the zinc-air batteries with KOH electrolyte are the first metal-air system brought into service. 

A series of primary zinc-air cells are developed with capacity ranging from 100 Ah to 3300 Ah and nominal currents ranging from 2 A to 50 A. Technologies for the production of the air electrodes, porous zinc electrodes and for the assembling of the cells are elaborated. Some of the developed zinc-air cells are in production since 1981. 

The high capacity, low power zinc-air cells from the types ZV500 and ZV3000 are used as a power supply of navigation buoys in Baltic see for more than 10 years. Batteries from these cells operate for more than 1 year continuously. Zinc-air cells from the same types are successfully used in Bulgarian Himalayan expeditions (Lhotze 1981, Everest 1984 and Anapuma 1986) as power supply of the telecommunication system and electric light at the base camp. It must be underlined that in these cases the zinc-air cells... 

Active carbon promoted with small amount of silver is used as catalyst in the air electrodes of these cells. In Figure 15 we presented the discharge curve of the zinc-air cell ZV3000 at constant current 1 A. 

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