Sectioned centre of a Leclanche cell made by the Ever Ready Company of Great Britain. This 'dry' cell was developed in the 1860s by the French chemist, Georges Leclanche (1838-1882). It had one zinc rod electrode and a carbon rod inside a pot of manganese dioxide and carbon granules (pictured here). An elecrolyte solution of ammonium chloride lay between the zinc and carbon rods. Since it did not contain any dangerous acids this relatively safe and portable 'battery' became very popular. It was the forerunner of the dry battery, which used the same chemical constituents.
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