Alessandro Giuseppe Antonio Anastasio Volta devised the operating principles of all batteries in 1799. Others followed by laying his invention horizontal, and encasing it in a box. Those early inventors could only guess what made their devices work. This article takes us back to battery operating principles which never cease to astound us.
Back to Basic Battery Operating Chemistry
All batteries, and similar devices including flow cells, are able to receive, store, and release electricity. Volta’s invention helped early scientists tame this energy, and launch us into our current era culminating in space travel.
The electricity in batteries is chemical potential available for release. However, this property is not unique to storage cells. We can also release chemical potential in the form of heat by lighting a camp fire. In both cases we turn potential into useful energy.
We can ignite a log in a camp fire by heating it, because wood is a natural phenomenon. However, we first have to build a battery, because it is a human invention as we share in this short video.
That video demonstrates how a working battery consists of an electrolyte, preventing direct contact between terminals of different materials. However, those three elements do need to have complementary chemical compositions.
How a Battery Converts Potential to Electricity
Getting back to battery operating fundamentals, we note how those three constituents are almost invariably an anode, a cathode, and an electrolyte. However, this potential needs a fourth element to release the energy through, just as lightening needs an earth to complete a circuit.
This fourth element of a battery is therefore an external circuit though which electricity travels between two terminals. Electrons travel between the cathode and the anode delivering electricity through this device. While balancing ions shuttle inside the battery, restoring equilibrium to complete the picture for now.

More Information
The Beginning of Batteries Dawns, Surprisingly
Wilhelm Sinsteden Invents Lead-Acid Battery