Batteries are everywhere. The modern world is dependent on these portable sources of energy, which are found in everything from mobile devices to hearing aids to cars. ????
But despite their prevalence in people's daily lives, batteries often go overlooked. Think about it: Do you really know how a battery works? Could you explain it to someone else?????
To envision how a battery works, picture yourself putting alkaline batteries, like double AAs, into a flashlight. When you put those batteries into the flashlight and then turn it on, what you're really doing is completing a circuit. The stored chemical energy in the battery converts to electrical energy, which travels out of the battery and into the base of the flashlight's bulb, causing it to light up. Then, the electric current re-enters the battery, but at the opposite end from where it came out originally.
All of the parts of the battery work together to make the flashlight light up. The electrodes in the battery contain atoms of certain conducting materials. For instance, in an alkaline battery, the anode is typically made of zinc, and manganese dioxide acts as the cathode. And the electrolyte between and inside those electrodes contains ions. When these ions meet up with the electrodes' atoms, certain????electrochemical reactions????take place between the ions and the electrodes' atoms.????
The series of chemical reactions that occurs in the electrodes are collectively known as oxidation-reduction (redox) reactions. In a battery, the cathode is known as the oxidizing agent because it accepts electrons from the anode. The anode is known as the reducing agent, because it loses electrons.???? ????
Ultimately, these reactions result in the flow of ions between the anode and the cathode, as well as the freeing of electrons from the atoms of the electrode, Sastry said.????</div