What Are Amps, Volts, Run Time and Battery Chemistry?
Every battery has two ratings which are volts and amp-hours (AH). The Ah rating may also be given as milliamp-hours (mAh), which are one-thousandth of an amp-hour ( for example, a 2Ah battery is equal to 2000mAh). Ah hours are a rating of the amount of energy that a battery can store. Typically, the mAh rating is also a measure of the number of hours a battery may last. For example, a 2000mAh battery will last at least 2 hours. The higher a battery's amp hour rating is, the longer the battery's run-time will be. It is not uncommon for some of our batteries to have higher or lower amp ratings. This will not cause any incompatibilities.
Voltage ratings, however, must be within a reasonable range. For instance, your original battery may say 3.6v, but you purchase a battery that is 3.7v. This is still acceptable. The rule of thumb when dealing with voltage is to never exceed one volt higher than your original rating. So if your original battery is rated at 3.6v, then you would be able to use a replacement battery up to 4.6v and nothing higher.
Run times vary for many reasons, such as the type of device, the type of applications being used, whether or not you are playing a cd or dvd and the chemistry of the battery. The average computer should give you between 1½ to 3 hours of run time. Once again, this varies for many reasons.
There are two main cell types of batteries that we carry. They are Li-ion and Ni-MH. "Li-ion" stands for Lithium Ion and "Ni-MH" stands for Nickel Metal Hydride. Li-ion batteries are 50% lighter compared to Ni-MH batteries and will run your device about 50% longer, thus they are more expensive.
Other cell types for batteries do exist. One older type is Ni-Cd which stands for Nickel Cadmium. These cells have been replaced by Ni-MH technology making them very much alike and compatible. Another newer type of cell is Li-pol which stands for Lithium Polymer. This is the most recent cell type which is currently being used to replace Lithium Ion cells. Although Li-pol cells are lighter and last longer than Li-ion ones, they are still both compatible cell types.