How Do Lithium Ion Laptop Batteries Work?

As you surf this site and the Web, you'll find that lithium ion (LiON) laptop batteries are extremely popular; they are the most used type of laptop battery. Many take this wondrous atom for granted, but knowledge of how the LiON battery discharges and recharges might just make you work a bit more efficiently while considering what exactly changes the battery life for each battery. Note that many laptops have the same battery, but the battery lives are different.

It's time to revisit basic chemistry. Anodes have a negative charge, while cathodes have a positive charge. These two are the names of the sides of LiON batteries. With these charges, batteries can move electrons around (remember that electrons determine stability and bonding!) to attract the lithium ions in the same direction. Anodes are carbon, while cathodes are Lithium cobalt oxide (LiCoO2). As a battery discharges, a simple process happens:

1. The carbon anode releases electrons to move towards the cathode side.
2. Lithium ions previously attached to carbon move with the electrons to bond with LiCoO2.
3. A current is given off from the cathode side, which is your battery power.
4. Current given off attracts electrons to the cathode.

Something similar happens for recharging, except that the current comes from an outside source, and the electrons will then move from cathode to anode, bringing the lithium ions with them. This is how a battery is recharged, and this is also why LiON batteries don't have the memory effect (lithium ions are natural, they simply "follow their own rules).

You probably know that a LiON laptop battery will be absolutely ruined if it is discharged completely. This means that the voltage is way down, and there's not enough energy. As all atoms have some required energy, no energy means that the ions just won't recharge/give off power. LiON batteries also are ruined if they sit for 3 years, regardless of use. This is because of the decay rate of lithium. As they decay, they simply age. LiON batteries sadly only last a few years. Now that you know how a LiON battery charges and discharges, make use of your battery wisely. Don't let it discharge completely, don't let it sit. Proper care of your battery, obviously, is important to battery life, and knowing the basic concepts of the function of LiON batteries will make this easier.