NiCad batteries are one of the oldest technologies used for OEM and replacement laptop batteries. However, although this technology is used in rechargeable devices for mechanical devides, it is not used in today's replacement laptop batteries. NiCad batteries are heavy compared to todays laptop and notebook batteries and have a poor power to weight ratio. NiCad laptop batteries are also subject to memory effect. The NiCad batteries also are manufactured with heavy metals, and are difficult to dispose of in an environmentally friendly manner.

Nickel Metal Hydride (NiMH) batteries succeeded NiCad batteries in laptop computer use. They are less prone to memory effects and the offer a better power to weight ratio than NiCad batteries. However, NiMH battery technology has, for the most part, been discontinued for the manufacture of replacement laptop batteries.

Today, most OEM and replacement laptop battery manufacturers employ Lithium Ion (Li-Ion) technology. Since they are relatively light compared to their power, they are also commonly found in cell phones and digital cameras and camcorders. Li-Ion batteries do not suffer from the memory effect phenomenom and are easier to dispose of than the older technologies. However, these batteries tend to lose their power charge quickly when then are near the end of their useful life, so consider this a warning that a replacement laptop battery will soon be required if you find that your laptop battery will not hold its charge.

Your laptop computer battery's life will vary depending on how your laptop comuter is configured and used. Operating time can be expanded by adjusting the screen's brightness to a lower level, disabling unused peripheral devices and exiting any unused software applications. Most laptop computer's have a software utility to adjust the computer's laptop battery power options. Today's laptop batteries will generally power a laptop computer for anywhere from two to five hours depending on the charge capacity of the OEM or replacement laptop battery and the computer's power requirements.

When buying a replacement laptop battery for your computer, you will likely find several options availabe from both the original equipment manufacturer and the secondary manufacturers. Although you will need to purchase the same battery technology and voltage rating as the original battery, consider upgrading your computer's operating life by purchasing a replacement laptop battery with a higher amperage rating.