Takeaway: Mike Jackman explains the differences among nickel cadmium, nickel metal hydride, and lithium ion batteries, and how to properly maintain each for optimal performance.

It’s vital hardware, and your laptop isn’t going to get very far without it, but how often do you give a thought to your battery? In this Daily Feature, I’m going to give you some powerful facts that will get you charged about batteries.

What’s under the hood?
Three types of batteries power the laptops you’ll find in service today, nickel cadmium (NiCad), nickel metal hydride (NiMH), and lithium ion (Li-ion), with Li-ion being the most common in newer laptops. Each battery type has a different chemistry for generating a charge and, therefore, different characteristics.

Capacity
The capacity of batteries is measured by power delivered per battery weight, rate of self-discharge, and useful cycles. Power is often measured in watt-hours per kilogram, or Wh/kg. Self-discharge refers to the fact that all batteries lose power when they’re stored. Cycle refers to how many times a battery can be taken from a full charge to a full discharge before the battery can no longer hold power.

The fact that batteries discharge over time is affected by temperature. At higher temperatures, the discharge rate is faster. The general rule to follow is to store them in a cool place and use them at room temperature.

Nickel cadmium
In tests performed in a lab by Cadex Electronics, Inc., nickel cadmium batteries had a life of 1500 cycles, which mea