The principle of the electrochemical conversion device…

The principle of the electrochemical conversion device known as the fuel cell, discovered by German chemist Christian Friedrich Schönbein in 1838, is published in the January 1839 edition of the "Philosophical Magazine.”

Later in 1839, Schönbein observes the odor of ozone, an isotope of oxygen, while using electrical equipment in a poorly ventilated laboratory.

Investigating its properties, he recognizes it as a unique chemical, naming it ozone the following year.