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In the 1860's, George Leclanché of France developed what would be the forerunner of the world's first widely used battery--the zinc carbon cell. The anode was a zinc and mercury alloyed rod. (Zinc, the anode in Volta's original cell, proved to be one of the best for the job.) The cathode was a porous cup of crushed manganese di and some carbon. Into the mix was inserted a carbon rod to act as the current collector. Both anode and the cathode cup were plunged into a liquid solution of ammonium chloride, which acted as the electrolyte. The system was called a "wet cell." Though Leclanché's cell was rugged and inexpensive, it was eventually replaced by the improved "dry cell" in the 1880's. The anode became the zinc can containing the cell, and the electrolyte became a paste rather than a liquid--basically the zinc carbon cell that is known today.
This dry cell is a very common general purpose, battery. The cells are very cheap, bobbin format and, correspondingly, their performance is generally poorer than other systems at high currents, especially at low temperatures. "High power" versions, with improved low temperature performance, use a better cathode mix and a zinc chloride electrolyte in place of ammonium chloride. For cylindrical cells, the zinc anode also serves as the cell can.
