Components of lithium-ion batteries, how do they work?

Lithium-ion batteries play a major part in our day-to-day lives and have shaped how we store and use energy for our appliances and devices. From laptops to home batteries, to electric cars, and phones, lithium-ion battery technology is becoming more entwined in our daily activities as the demand for batteries continues to increase across the globe.


So, how do lithium-ion batteries work and what are they made of?


Here is a rundown on what you need to know about the composition of lithium-ion batteries that make up the energy storage in your phone and even similarly in your LG RESU.


The mechanisms


Within a lithium-ion battery cell, there are four elements that play important roles.


Cathode – The cathode is where lithium is placed in a lithium-ion battery on one end.


Anode – The other end of the battery in which lithium can be stored and released.


Electrolyte – A liquid that sits between the cathode and anode, carrying the lithium ions between both ends of the battery.


Separator – A microporous layer that physically separates the cathode and anode, while allowing for the ions to pass through to both ends of the cell.



Source: LG Energy Solution

In usage


A lithium-ion battery uses the electrolyte to carry the positively charged lithium ions from one end of the battery (cathode) to the other end (anode) and vice versa through the separator. When the battery is discharging or in use, the positively charged ions move from the anode to the cathode, in doing so, this also creates free electrons which move to the other side of the battery through a conducting wire. When the battery is charging, the opposite occurs, lithium ions are sent from the cathode to the anode, allowing for further use of the battery.