Alessandro Volta's main invention was the battery, of which he made several versions. He also invented the electrophorus and he discovered and isolated methane gas.
In the late 1700s and early 1800s when science was much less advanced than it is now, Alessandro Volta's inventions and discoveries were major strides in the science of the day.
Voltas invention of the electrophorus
It was only a year after Volta was appointed as professor of Physics in the Como high school that he made his first major invention.
Volta's invention was the improved electrophorus. The device itself was invented in 1762 by Swedish professor Johan Carl Wilcke but Volta improved and popularized the device. Sometimes the electrophorus is credited as one of Alessandro Volta's inventions.
The electrophorus was a simple manual capacitive generator used to produce electrostatic charge via the process of electrostatic induction. It comprised two metal plates, one of which was covered with ebonite - a material used as an insulator. Negative static charge was repeated built up on the ebonite, or other insulator. When a second plate with an insulated handle was brought near, the ebonite attracted a positive charge in the second plate, which collected on the side nearest the ebonite. The side of the plate opposite the ebonite was left with a negative charge.
It was then possible to drain the charge from the ebonite and then recharge it by rubbing again and then repeat the process to build up a considerable level of positive charge on the second plate.
The invention of the electrophorus enabled the Leyden jar that had been previously used to be superseded, although it still remained in use for years after the electrophorus was invented.
Voltas invention of the crown of cups
Another of Alessandro Volta's inventions was the crown of cups battery. The invention started with work undertaken by Luigi Galvani. He had been investigating electricity and its effects on animal tissue. He discovered that when two dissimilar metals touched the muscle in a frog it caused it to twitch - he reasoned that animal electricity was released.
Volta started his own investigations and found that the animal tissue was irrelevant to the release of electricity. He discovered that it was the two dissimilar metals placed into a fluid that caused electricity to flow.
To prove his point, Alessandro Volta invented the crown of cups battery. He arranged a series of cups in the shape of a circle or crown and filled them with saline solution. Into each one he placed two strips of metal, one of copper and the other of tin or zinc. Bending the metal strips to remain in place, he connected them together, copper to zinc, etc, making Alessandro Volta's invention of the world's first electrical battery.
The crown of cups battery invention was a major milestone in electrical technology. The invention of the battery enabled electric current flow to be used and investigated in a totally different way - previously only static electricity had been used.
Alessandro Voltas pile invention
The crown of cups occupied a large amount of space and was not particularly easy to use. To improve its usability and performance, Volta invented a new format for the battery. Called Volta's pile, he used discs of copper, cardboard and zinc stacked on top of each other.
Alessandro Volta's invention of the battery in a pile or 'Voltaic Pile' format enabled batteries to be made in a far more manageable format.