Illustration of Alessandro Volta (1745-1827), Italian physicist. Volta invented the electric battery, announcing his discovery in 1800. His battery consisted of alternating disks of silver and zinc with brine-soaked card between them. Volta, professor at the universities of Como and Pavia, had started studying electricity in 1786. The International Standard (SI) unit of electrical potential difference, the volt, is named after Volta. Engraving by G. Bonatti after G. Garavaglia (1790-1835).