Throughout the years there have been many technologies involved with notebooks, and laptop batteries are no different. There are actually three distinct notebook battery types on the market today. Knowing the difference between them will help you decide on exactly what to get when the time comes for a purchase.
In this article I will discuss the three different laptop battery types, as well as some of the advantages each one carries.
Nickel Cadmium - NiCd batteries were actually the first rechargeable laptop batteries ever. Manufactures loved them because their cost was relatively low and they had a high output. You won't find Nickel Cadmium batteries being used anymore, due to them being heavier and not as efficient as the newer laptop batteries.
Nickel Metal Hydride - NiMH batteries can still be found all over the place -- particularly for older model laptops. The rechargeable NiMH laptop battery was a big step up for notebook technology mostly in part because they were more reliable than the NiCd batteries, and they had an even higher output. The NiMH battery was also cheaper to produce, and safer to use.
The only issue with NiMH batteries is that they can have a memory effect. Basically, if you don't fully discharge the battery, it can remember this and leave you with a less than perfect battery output.
Lithium Ion - LiON batteries are now used in most new laptops. Unlike the NiMH battery, LiON laptop batteries have no memory effect. LiON batteries are also lighter than both NiCd and NiMH notebook batteries. Both of these advantages equal out to the Lithium Ion battery being the most popular and most expensive among the various notebook power sources.
You are probably wondering which type of battery to get. Getting a Lithium Ion battery would be the best solution, and if you have the money that is what I recommend. If you cannot afford a LiON battery or your notebook is not compatible with one, then getting a NiMH battery is the next best thing.