Chemical Cell (Voltaic Cell, Daniel Cell)

Electric production before Voltaic Cell

Before a chemical cell, such as a battery, there was only one way of knowing how to produce electricity. It is rubbing amber, glass, or metal.

Voltaic Cell

In the 18th century, Italy, Alessandro Volta (1745-1827) attempted to create electricity chemically. He made a voltaic cell by inserting salted wet paper between a small copper plate and a zinc plate. He stacked these cells vertically and can create high voltages.
This is the first battery of mankind. Voltaic cells generate hydrogen gas on the surface of the zinc plate. This gas blocked the flow of current, so efficiency was not good.

Daniel Cell

And then, Daniel of England (1790-1845) put copper plate and zinc plate in different containers. Then he crossed the container with a salt bridge. He was able to stop the generation of hydrogen gas in this way.
Daniel Cell is the first battery to work reliably.

(+)pole (zinc plate): Zn → Zn2+ + 2e-
(-)pole (copper plate): Cu2+ + 2e- → Cu