The Edison–Lalande cell was a type of alkaline primary battery developed by

Thomas Edison Thomas Alva Edison (February 11, 1847October 18, 1931) was an American inventor and businessman. He developed many devices in fields such as electric power generation, mass communication, sound recording, and motion pictures. These inventi ...

from an earlier design by Felix Lalande and Georges Chaperon. It consisted of plates of copper oxide and

zinc Zinc is a chemical element with the symbol Zn and atomic number 30. Zinc is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodi ...

in a solution of

potassium hydroxide Potassium hydroxide is an inorganic compound with the formula K OH, and is commonly called caustic potash. Along with sodium hydroxide (NaOH), KOH is a prototypical strong base. It has many industrial and niche applications, most of which exp ...

. The cell voltage was low (about 0.75 volts) but the internal resistance was also low so these cells were capable of delivering large currents. The cell could be replenished with fresh zinc and copper oxide plates and KOH solution for reuse.

History

Lalande–Chaperon cell

In 1880, the manufacturer De Branville and Company of 25 rue de la

Montagne Sainte-Geneviève The Montagne Sainte-Geneviève is a hill overlooking the left bank of the Seine in the 5th arrondissement of Paris. It was known to the ancient Romans as .Hilaire Belloc, '' Paris (Methuen & Company, 1900)'' Retrieved June 14, 2016 Atop the Mon ...

, Paris exploited the patent of Lalande and Chaperon to build copper oxide batteries. In 1887, the French submarine Gymnote (Q1) was built. The boat was originally fitted with 540 Lalande–Chaperon alkaline cells which used

and copper oxide electrodes with

electrolyte, manufactured by Coumelin, Desmazures and Baillache.

Edison–Lalande cell

Edison improved on the Lalande–Chaperon cell by replacing powdered copper oxide with copper oxide briquettes.

Poerscke–Wedekind cell

Another modification to the Lalande-type cell was patented by Heinrich Poerscke and Gustav Wedekind in 1905, British patent GB190416751. In this cell, the copper oxide depolarizer was pasted on the inside of a

cast iron Cast iron is a class of iron– carbon alloys with a carbon content more than 2%. Its usefulness derives from its relatively low melting temperature. The alloy constituents affect its color when fractured: white cast iron has carbide impuri ...

pot. When the depolarizer was exhausted, the cell was dismantled and the liquid was poured out. The pot was then heated in air to re-oxidize the deposited copper to copper oxide. The Neotherm cell, by

Siemens Siemens AG ( ) is a German multinational conglomerate corporation and the largest industrial manufacturing company in Europe headquartered in Munich with branch offices abroad. The principal divisions of the corporation are ''Industry'', ''E ...

, was similar.

Chemistry

The zinc anode dissolves (is oxidised) in the hydroxide solution to form zincate anions, consuming hydroxide ions in the process; electrons enter the external circuit: : Zn⁰ + 4 OH⁻ → n(OH₄)sup>2− + 2 e⁻ Half of the hydroxide ions are replenished by the hydration and reduction of the copper oxide cathode to copper metal by the electrons travelling in the external circuit: : CuO + H₂O + 2 e⁻ → Cu⁰ + 2 OH⁻ The overall reaction is: : Zn⁰ + 4 OH⁻ + CuO + H₂O → n(OH₄)sup>2− + Cu⁰ + 2 OH⁻

Applications

Applications for Lalande-type batteries included submarine power (see above), railway signalling. and powering Edison's electric fans and

phonograph A phonograph, in its later forms also called a gramophone (as a trademark since 1887, as a generic name in the UK since 1910) or since the 1940s called a record player, or more recently a turntable, is a device for the mechanical and analogu ...

References

{{DEFAULTSORT:Edison-Lalande cell Battery types