He had been paying a lot of attention to the experiments of his friends, Professor Galvani. Galvani had accidentally discovered that two different metals in a special liquid will produce electrons. From Galvani's discovery, Volta got his idea for the wet cell. He used small round plates of copper and zinc as electrodes. Between them, he placed discs of cardboard soaked in salt water.
Salt water is an electrolyte.
When Volta attached a wire to the top and bottom of the pile, an electric current passed through it. Volta's wet cell is called the Voltaic Pile. He became famous for it. He received many medals and even became Count Volta. Emperor Napoleon called him to France in 1801 to demonstrate his experiments.