Zinc Batteries

Batteries. Many batteries intended for household use contain mercury or mercury compounds. In the form of red mercuric oxide [21908-53-2] mercury is the cathode material in the mercury—cadmium, mercury—indium—bismuth, and mercury—zinc batteries. In all other mercury batteries, the mercury is amalgamated with the zinc [7440-66-6] anode to deter corrosion and inhibit hydrogen build-up that can cause cell mpture and fire. Discarded batteries represent a primary source of mercury for release into the environment. This industry has been under intense pressure to reduce the amounts of mercury in batteries. Although battery sales have increased greatly, the battery industry has aimounced that reduction in mercury content of batteries has been made and further reductions are expected (3). In fact, by 1992, the battery industry had lowered the mercury content of batteries to 0.025 wt % (3). Use of mercury in film pack batteries for instant cameras was reportedly discontinued in 1988 (3). 

Fig. 7. Performance comparison of "D"-size alkaline—manganese vs carbon-zinc batteries at 21°C on (a) alight drain 150-Q continuous test at 21°C, and...

Some efforts toward sealed battery development (76) were made. However, a third electrode, an oxygen recombination electrode was required to reduce the cost of the system. High rate appHcations such as torpedo propulsion were investigated (77) and moderate success achieved using experimental nickel—zinc ceUs yielding energy densities of 35 W-h/kg at discharge rates of 8 C. A commercial nickel—zinc battery is considered to be the most likely... 

Final Report, Design and Cost Study of Nickel—Zinc Batteries forElectric Vehicles, ANE Contract No. 31-109-38-3541, Energy Research Corp., Oct. 1976. 

The dry cell was invented by Leclanche in the 1860s. This type of battery was developed in the 19th century. In the 1940s, Rubel achieved significant progress in alkaline-zinc batteries, and manufactured zinc powder with high surface area to prevent zinc passivation. 

K. Kordesch, J. Daniel-Ivad, Ch. Faistauer, High power rechargeable alkaline manganese dioxide-zinc batteries, 182nd Meeting of the Electrochem. Soc., Toronto, Oct., 1992, Extended Abstract 92-2, p. 18-18 (6 AA-bundle battery replacement of single D-cell). 

The other example, called the nickel/ zinc battery [(-Zn)/KOH/NiOOH(+)], has attracted more attention in two different versions from the "application" and "cell design" viewpoints one is the small cylindrical consumer cell [30], the other one is the flat-plate module for electrotraction [31], A very interesting review with an extended collection of references was pub-... 

In rechargeable nickel/zinc and sil-ver/zinc batteries this problem is partly compensated for by provision of a massive zinc reserve. The cells are cathode-limited and the amount of anode material exceeds the theoretically required mass by a factor between two and three. 

M. Klein, F. McLarnon, Nickel zinc batteries in Handbook of Batteries, 2th ed. (Ed. D. linden), McGraw-Hill, New York, 1995,p. 29.4. 

P.E. Streigle, Activator Investigation For A Silver Oxide—Zinc Battery (U) , Catalyst Research Corp, Md, Rept No 2, AADLPA Contract No DA-28-017-AMC-3433(A) (1967)... 

Often, the oxides of certain metals are used as the oxidizer. In the names of systems and batteries, though, often only the metal is stated, so that the example reported above is called a silver-zinc, rather than silver oxide-zinc battery (or system). 

Mercury reduction in household batteries began in 1984 and continues today. During the last five years, the industry has reduced the total amount of mercury usage by about 86%. Some batteries such as the alkaline battery have had about a 97% mercury reduction in the product. Newer alkaline batteries may contain about one-tenth the amount of mercury previously contained in the typical alkaline battery. Some alkaline batteries have zero-added mercury, and several mercury-free, heavy-duty, carbon-zinc batteries are on the market. 

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

G—Zinc Zinc anode, alkaline Manganese dioxide, nickel Primary and Nickel-zinc batteries and... 

Causes of spontaneous combustion and other hazards of silver-zinc batteries were investigated. 

The effective service life of Air/PANI-Zn battery can be greater by several folds than that of conventional alkaline air-zinc batteries owing to the absence in principle of electrolyte carbonization (pH < 7). 

The cathode can of an air -zinc cell has a hole for the air access (the respiratory hole). The substitution of the cathode oxides, which are used in traditional batteries, with air increases capacity and energy density of such a battery. The battery voltage depends first of all on the air potential, which at constant current density and temperature is also constant hence the voltage of an air-zinc battery at the discharge practically does not change. 

The air humidity influences the performance parameters of the air-zinc batteries. At high air humidity the electrode flooding is possible. On the other hand, at low air humidity a concentration of the electrolyte increases, the air electrodes get too dry. 

Button cells consist of cathode and anode cans (used as the terminals), powdered zinc anode, containing gelled electrolyte and the corrosion inhibitor, separator with electrolyte, thin (0.5 mm) carbon cathode with catalyst and PTFE, waterproof gas-permeable (teflon) layer and air distribution layer for the even air assess over the cathode surface. Parameters of battery depend on the air transfer rate, which is determined by quantity and diameters of air access holes or porosity of the gas-diffusion membrane. Air-zinc batteries at low rate (J=0,002-0,01C at the idle drain and J= 0,02-0,04C at the peak continuous current) have flat discharge curves (typical curve is shown by Figure 1). 

In this connection, Servos mentions, among others, Robert Bunsen at Heidelberg, who invented the carbon-zinc battery and the spectroscope H. H. Landolt at Bonn, later Berlin, who studied the refractive power of the molecule in relation to the refractivities of its atoms Heinrich Rose at Berlin, who followed up on Berthollet s theory of mass action and Cato Guldberg and Peter Waage in Norway, who did so more thoroughly. See John W. Servos, Physical Chemistry from Ostwald to Pauling, 1115. 

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