On 20th of March 1800 Alessandro Volta reported in a letter to Joseph Banks, president of the Royal Society of London, the invention of an electric battery.

Alessandro Giuseppe Antonio Anastasio Volta (18 February 1745 – 5 March 1827) was a pioneer in the field of electricity and power.

He invented the voltaic pile – an electric battery which could produce a steady electric current.

In announcing his discovery of the voltaic pile, Volta paid tribute to the influences of William Nicholson, Tiberius Cavallo, and Abraham Bennet.

The battery made by Volta is credited as one of the first electrochemical cells. It consists of two electrodes: one made of zinc, the other of copper. The electrolyte is either sulfuric acid mixed with water or a form of saltwater brine. The electrolyte exists in the form 2 H⁺ and SO²⁻
₄. Zinc metal, which is higher in the electrochemical series than both copper and hydrogen, is oxidized to zinc cations (Zn²⁺) and creates electrons that move to the copper electrode. The positively charged hydrogen ions (protons) capture electrons from the copper electrode, forming bubbles of hydrogen gas, H₂. This makes the zinc rod the negative electrode and the copper rod the positive electrode. Thus, there are two terminals, and an electric current will flow if they are connected.

Wikipedia

He demonstrated the working battery to Napoleon in Paris in 1801 who bestowed on him great honours. The battery was a success and was improved upon by others who followed on from him. The volt is named after him.