Replacement Laptop Batteries

External laptop battery packs, also known as universal laptop batteries, are great when you need to power your laptop for an extended period of time and you will not be able to charge your computer's internal battery or power it on AC via the charger itself. This is especially true for the professional that logs his or her hours 'in the field'. An external laptop battery 'system' will include the battery pack itself, a charger for it and a cable and plug to fit your laptop's power input terminal. Most external battery packs can be used with a variety of notebook PCs (providing that the electrical specifications are met) and therefore are supplied with an assortment of adapters to accomodate a range of power input terminals.

Targus APM12US External Battery

Purchasing an external laptop battery requires careful selection to ensure the safe operation of your computer due to the wide ranging electrical requirements found in laptops, notebooks and tablet PCs. Critical consideration must be given to the voltage (V) and amperage (A) ratings of the computer when selecting an external battery. Another specification to consider in the purchase of an external battery is the watt-hours (W-Hr) since a higher W-Hr rating will power the computer for a longer period of time than one with a lower rating. However, while the voltage and amperage selection is critical in the selection process, the watt-hour rating is generally more of a convenience criteria.

You may be able to find the laptop manufacturer's electrical specs for your computer from their web site or in your user's manual, but the easiest and most readily way to obtain that is to examine the charger that came with your notebook. You should easily be able to read the label on the OEM charger and find the voltage and amperage specs on it. Many, if not most, external batteries have voltage outputs that are switch selectable for two or more voltages. You will need to select an external battery that has a voltage output that matches your laptop's voltage requirement. Voltage specs of +/-1 will generally also work with your computer system, but you should check with the battery supplier if you need more information. You will also need to give careful consideration to the amperage spec of both your laptop and the external lapop battery. The external battery will need to be rated higher than the laptop's spec for amps or it won't be able to supply enough current to power the computer.