1-158-114 - Oxford Science Archive/Heritage Images

Leclanche wet cell, an early storage battery, 20th century. Invented by the French engineer Georges Leclanche (1839-1882), this was an early form of the zinc carbon (dry cell) battery, the first widely used storage battery. It consists of a glass vessel containing a zinc rod (left), and a central porous cell of a carbon block surrounded by small pieces of carbon and manganese dioxide and sealed with pitch. The conducting fluid or electrolyte is a strong solution of chloride of ammonia. They were used as a power source in early telephones.