Air batteries

Both primary and secondary metal-air batteries have been considered for mobile applications. The metal negatives involve mainly zinc and iron, in rechargeable, and aluminum, in primary systems. 

Discussion of the oxygen electrode performance is beyond the scope of this chapter (recent reviews are available ). The main disadvantages introduced by state-of-art air electrodes in EV 

The merits and disadvantages introduced by iron or zinc negatives have been previously discussed (Sections III.2 and III.3). 

The iron-air battery has been under development in Sweden (SNDC, SAB NIFE, KTH ), the USA (Westinghouse Electric 160,165 (SAFT), West Germany (Siemens A.G. ), and 

A1 + NaOH + H20 + IO2 NaAl(OH)4 The chemical reaction in the crystallizer produces hydrargillite NaAl(OH)4 NaOH + Al(OH)3 

Hissel, H. Gualous, C. Turpin, Electrochemical Components, ISTE, London, John Wiley Sons, New York, 2013. 

3 Of course, during discharge, the oxygen combines with the positive electrode, which decreases the gravimetric energy density. 

Because of its very low molar mass (6.9 g/mol), lithium, as a metal, is obviously a very attractive choice to make the negative electrode, which led to the introduchon of the lithium-dioxygen system (or lithium-air the molar mass of oxygen is 16 g/mol) as a rechargeable element, first advanced in 1976. Also, in the electrochemical reactions in which they are involved, the lithium at the negative electrode (E°(Li /Li) = -3.05 V/NHE) and the oxygen at the positive electrode (E°(02/0H ) = 0.40 V/NHE in an aqueous medium, and E°(02/0 ) = 1.12 V/NHE in an anhydrous medium) offer a significant difference of redox potential of 3.45V or 4.17V. 

Bennion, E. L. Littauer, Mathematical model of a lithium water electrochemical power cell. 7. ofElectrochem. Soc., 123,1462-1469,1976. 

5 The mass of the battery increases over the course of discharge, because oxygen is absorbed by the positive electrode. 

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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).

Fig. 27. Cross-section of SNDC iron—air battery pile (93).

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.,... 

EAR Energy Resources, which develops Zn-air batteries for portable computers, claims about 250 Wh for a computer unit. The price (in 1994) was 600, including the charger. For the first discharge, ten operating hours are claimed. However, it must be realized that the subsequent cycle behavior is not well established. Sony s Li... 

Aluminum is directly applied in its metallic form when it serves as battery anode. The battery concepts considered are in general single-use types (primary batteries). The most developed systems belong to the metal-air batteries, using the reduction of atmospheric oxygen as the cathode reaction, e.g., (-) A1 / KOH / 02 (+) or (-) A1 / seawater / 02 (+). The main discharge reactions are ... 

In acid electrolytes, carbon is a poor electrocatalyst for oxygen evolution at potentials where carbon corrosion occurs. However, in alkaline electrolytes carbon is sufficiently electrocatalytically active for oxygen evolution to occur simultaneously with carbon corrosion at potentials corresponding to charge conditions for a bifunctional air electrode in metal/air batteries. In this situation, oxygen evolution is the dominant anodic reaction, thus complicating the measurement of carbon corrosion. Ross and co-workers [30] developed experimental techniques to overcome this difficulty. Their results with acetylene black in 30 wt% KOH showed that substantial amounts of CO in addition to C02 (carbonate species) and 02, are... 

The overpotentials for oxygen reduction and evolution on carbon-based bifunctional air electrodes for rechargeable Zn/air batteries are reduced by utilizing metal oxide electrocatalysts. Besides enhancing the electrochemical kinetics of the oxygen reactions, the electrocatalysts serve to reduce the overpotential to minimize... 

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. 

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

Battery applications Titanium containing y-Mn02 (TM) hollow spheres synthesis and catalytic activities in Li-air batteries [123] Orthorhombic LiMn02 nanorods for lithium ion battery application [124] Electrochemical characterization of MnOOH-carbon nanocomposite cathodes for metal—air batteries [125] Electrocatalytic activity of nanosized manganite [126]... 

Hu, C., Liao, S., Chang, K., Yang, Y. and Lin, K. (2010) Electrochemical characterization of MnOOH-carbon nanocomposite cathodes for metal-air batteries impacts of dispersion and interfacial contact. Journal of Power Sources, 195, 7259-7263. 

The last paper in this chapter is by Professor N. Korovin of Moscow Power Engineering Institute, Russian Federation. The author could not attend the NATO-CARWC in Chicago due to a last minute cancellation. His work, contributed to this volume is a comprehensive overview of various metal-air battery technologies, with a heavy focus on the role of carbon materials in these electrochemical systems. 

While during the NATO-CARWC, the session on metal-air batteries featured other important contributions, it is, perhaps, by coincidence that only presenters from the former Eastern Block submitted their papers for this volume. In this regard, the editors wish to note, that papers below may be of special interest to the western reader, as they offer a rather unique insight into the science and application of the metal-air battery systems from the... 

NEW CONCEPT FOR THE METAL-AIR BATTERIES USING COMPOSITES CONDUCTING POLYMERS / EXPANDED GRAPHITE AS CATALYSTS... 

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