Battery Types 

Before you learn how to prolong the life of your laptop battery, you need to determine what type you are using. The three dominant types of rechargeable batteries are Nickel Cadmium (NiCd), Nickel Metal Hydride (NiMH), and Lithium Ion (LiIon).

• Nickel Cadmium (NiCd): the most prevalent and rugged type of rechargeable battery on the market. NiCd batteries perform better in extreme temperatures and can endure approximately 750 charge and discharge cycles. However they are prone to "memory effect" when they are not completely discharged each cycle.
• Nickel Metal Hydride (NiMH): a step up from NiCd batteries. It offers up to 40 percent additional capacity compared to a NiCd battery of equal size. NiMH batteries are not as subject to memory effect degradation. These batteries generally have a life expectancy of approximately 400 charge/discharge cycles.
• Lithium Ion (LiIon): the newest technology in portable power. LiIon will deliver roughly twice the run time of a comparable NiMH battery. LiIon batteries are more expensive, however, and are available for a very limited number of devices. A charger designed specifically for LiIon batteries must be used to charge them. LiIon technology also has a life span of about 400 charge/discharge cycles and is completely immune to memory effect.

Memory Effect

NiCd batteries, and to some extent, NiMH batteries, suffer from what is called "memory effect." Memory effect occurs when a battery is only partially discharged before being recharged. The battery "forgets" that it has the capacity to further discharge all the way down. For example, if on a regular basis, you fully charge your battery and then use only 50 percent of this capacity before the next recharge, eventually the battery will become unaware of its extra 50 percent capacity, which has remained unused. The battery will remain functional, but only at 50 percent of its original capacity.

The way to avoid memory effect is to fully charge and then fully discharge the battery at least once every three to four weeks. Letting your laptop run on the battery until it ceases to function can do this.

Charging the Battery

When charging the battery for the first time, the device may indicate that charging is complete after just 10 or 15 minutes. This is normal with rechargeable batteries. New batteries are hard for the device to charge because they have never been fully charged and are not "broken in." Sometimes the device's charger will stop charging a new battery before it is fully charged. If this happens, remove the battery from the device and then reinsert it. The charge cycle should begin again. This may happen several times during the first battery charge. This is normal. Batteries that have been in storage or out of use for long periods of time should be reinitialized before being put back into service.

Conserving Battery Power

Here are some tips on conserving laptop battery power:

• Optimize the power management features provided on your system. Managing the power used by the hard drive will save significant amounts of power and will extend your usage time.
• Decrease screen brightness. On color systems, you can save quite a bit of power by changing to black-and-white (monochrome) mode.
  

Be sure to clean dirty battery contacts with a cotton swab and alcohol. This helps maintain a good connection between the battery and the portable. Also, if you don't plan on using the battery for a month or more, store it in a clean, dry, cool place away from heat and metal objects. NiCd, NiMH, and LiIon batteries will self-discharge during storage. Remember to recharge the batteries before use.

Cleaning and Replacement 

After a certain number of charging cycles, your battery will no longer charge fully and will not give you its initial performance. This is due to normal wear and tear, and unfortunately, you can do nothing about it. You do have a couple of options at this point. You can dispose of your battery and buy a new one, or you can have the worn-out battery refurbished.

If you dispose of your battery, please dispose of it properly. These batteries should not be thrown in the trash. They should be taken to a recycling facility.

Refurbishing is an economical alternative to buying a new battery. Most battery packs can be rebuilt to like-new condition to provide you with more years of continued service.