Batteries store energy over long periods of time and make that power conveniently available in the form of electricity. The Molecular Expressions website points out that "dry cell," zinc carbon batteries are the most common type of stored electrical energy, found in devices like flashlights and calculators.
The heart of the dry cell is a rod made of graphite or another form of carbon derivative. This electrode is submerged into a electrolyte paste and wrapped in a thin metal outer cylinder.
Dry cell electricity comes from a chemical reaction in the battery. The electrode reacts with the ammonium chloride (NH4Cl) and manganese dioxide (MnO2) metal paste, oxidizes, and releases charged particles. According to EDinformatics, dry cells lose their electricity as the chemical changes become complete.
The average electric output of dry cells is about 1.5 volts of DC power. An article on the Kapi'olani Community College Library website suggests linking dry cells in a series to boost the voltage output.
In the late 1880s, Karl Gassner developed a dry cell that formed a chemical reaction with zinc oxide and a water mixture. Another inventor, Georges Leclanche, later replaced this design with a more stable ammonium chloride solution.