A battery is a kind of device that makes an energy of a chemical reaction converted into an electricity. This process was made through immersing two metals in an electrolic solution, by which a nonmetallic (electrolyte) dissociates into ions or in a charge components.

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According to their electrochemical activity, the metals must be selected. Electrochemical activity depends on their ability to gain or lose electrons.

The gain and lose of electron will cause potential differences. or voltage between this two metals.

A current of electrons will flow from the “anode” (first metal) through the wire going to the load and goes through the “cathode” (the second metal). Through the electrolytic solution, ions carry the current and complete the circuit.

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The “anode” is negative and the “cathode” is positive in consideration with the electron current moving through the wire and the load. Meanwhile, with regards to the ion current, the “anode” is positive and the “cathode” is negative because the “anode” will be coat by the positive ions and make it appear positive.

The “anode is the metal which release electrons to the wire as well as positive ions to the solution while the “cathode is the metal that accepts electrons from the wire as well as accepting ions from the solution.

When compared to the “fuel cells”, they differ in the matter that the fuel “cells” are supplied with reactants from outside source, while the batteries contains all the chemical to be used in the reactions.