Batteries are simply a controlled chemical reaction designed to provide electrons on the anode electrode to power an electrical circuit. This is an important idea to keep in mind when discussing battery technology. Despite the fact that batteries are used to power electronics, batteries must follow the laws of chemical reactions and are constrained by those physical laws. Simply put, chemistry is the key to a well designed battery.
Batteries are categorized into primary and secondary batteries. The difference between the two types of batteries is that secondary batteries can be recharged; that is, the chemical reaction that moves the free electrons to the cathode and powers the electrical circuit can be reversed. By driving an electric current through the battery, you can force the battery to create positive and negative ions on the cathode and anode so that it can be used to provide electricity again. Secondary batteries are also known as rechargeable batteries or storage batteries.