Volt invented the battery.
In 1799, the Italian physicist Volt dipped a zinc plate and a tin plate in salt water and found that there was current flowing through the wires connecting the two metals. Therefore, he put a lot of fluffed cloth or paper sheets soaked in salt water between the zinc sheets and the silver sheets.
When you touch both ends by hand, you will feel strong current stimulation. In this way, Volt succeeded in making the world's first battery, the "Volt Stack." This "volt stack" is actually a battery pack in series. This became the power source for early electrical experiments and telegraph machines.