The lithium-ion batteries energies millions of its users every day. The use of this battery is from cell phones to electric cars in order to improve the quality of human life. As an engineer or technical person it is very common to know the lithium ion battery working principle.
To understand the battery mechanism, you should first learn some basics. This basic will help you to learn the battery principles quickly.
Basics On Battery:
- Electrode: Electrodes are the negatively and positively charged ends of the cell. Electrodes stay connected with the current collectors.
- Anode: Negative electrode of a cell is known as an anode.
- Cathode: Positive electrode of a cell is known as the cathode.
- Electrolyte: An electrolyte is a liquid or gel-type material which carries electricity.
- Current Collectors : The current collectors are conductive metal foils connected to the battery's electrodes. The electrodes are connected to the battery terminals.
- Separator: It is a porous polymeric film that segregates the electrodes during the lithium-ion exchange.
Working Principle of Lithium-ion battery(lithium ion battery working principle):
->> The lithium is stored in the cathode and anode of the Lithium-ion battery.
->> The electrolyte transmits positive lithium ions from the anode end to the cathode end and vice versa using the separator path.
->> Thus the lithium ion moves and generates free electrons in the anode, which produces some free charges in the current collector.
->> This way, current flows through the device from the positive current collector to the negative current collector.
->> At last, the separator barriers the electron flow and stores energy inside the lithium battery.
Charging and discharging
Discharging means the anode end releases lithium ions to the cathode end and generates a current flow to power the device connected as load the battery. On the other hand, charging means the cathode end releases lithium ions and the anode end receives that ions.
Energy density and power density.
Two factors are essential to understand the battery principle: power density and energy density. The measuring unit of power density is watts per kilogram(W/Kg) which is the power quantity generated by battery against it's mass.
Watt hours per kilogram(Wh/Kg) is the unit of energy density, the quantity of energy a battery can store according to it's mass.
For example, Imagine a tank full of water and the draining process of the tank. Then the energy density is the size of tank and power density is the time required to drain the tank water.
