Like all rechargeable batteries, a notebook computer battery's ability to hold a maximum charge will decrease over time or with use.
Lithium-ion batteries used in notebook computers typically have a lifespan of 300 to 500 charge cycles. After a year of use or 300 charge cycles, a Lithium-ion battery holds only about 80 percent of its original capacity. But there are ways to extend a notebook battery's life, which reduces the need to buy additional batteries, which in turn is good for the environment.
First, conserve battery power by reducing power consumption on your notebook. Hewlett-Packard recommends several steps, such as keeping the computer cool (between 65 and 77 degrees Fahrenheit). You can also try adjusting screen brightness, removing peripherals and lowering processor speed.
Second, because high temperatures accelerate the deterioration of Lithium-ion cells, keep the notebook away from prolonged exposure to heat (for example, don't leave it in your car on a warm day). Also, remove the battery if the notebook is turned off and not plugged in to an AC adapter for more than two weeks -- or if the notebook is plugged in to AC power continuously for more than two weeks.
Third, calibrate the battery. When users power up in fits and starts and then recharge without fully draining the battery, it reduces the amount of power available in a single charge cycle and can render the battery meter inaccurate.
There are four steps to calibrating a battery:
Last, Lenovo Master Inventor Howard Locker advises against leaving a notebook always plugged in. "The battery will last longer if it charges and discharges, so you don't want it 100 percent charged all the time," he explains. "Once in a while, let the battery drain." But contrary to popular opinion, he says, it does not have to drain completely the first time it's used.