This is difficult to determine. Actual laptop battery running time depends upon the power demands made by the equipment. The use of the monitor, the hard drive and other accessories result in additional drain upon the battery, effectively reducing its running time. The total running time of the battery is also dependent upon the design of the equipment. Generally, a new BatteryFuel.com battery will run at least as long (and usually longer) as your old battery did when it was new.


BatteryFuel’s Laptop batteries have two main ratings on them: Volts and Amperes. Because size and weight of laptop batteries is limited when compared to larger batteries such as car batteries, most companies show their ratings with Volts and Milliamperes. One thousand Milliamperes equals 1 Ampere. When buying a battery, select batteries with the most Milliamperes (or mAh). Batteries are also rated by Watt-Hours, perhaps the simplest rating of all. This is found by multiplying the Volts and the Amperes together. For example:


14.4 Volts, 4000mAh (Note: 4000mAh is equal to 4.0 Amperes).
14.4 x 4.0 = 57.60 Watt-Hours


Watt-Hours signifies the energy needed to power one watt for one hour. This laptop battery can power 57.60 watts for one hour. If your laptop runs at 20.50 watts, as an example, this laptop battery could power your laptop for 2.8 hours. (57.60 battery watts/20.50 laptop watts = 2.8 hours or runtime)


You can find your laptop’s watt hour usage in the user or specification’s manual. Some laptop manuals will give more than one watt hour specification based on running the already installed OS by itself and or with one other program open as in the laptop’s word processor. Once you open up other programs and start adding pheriphials, the run time will be reduced. Please keep in mind that WiFi, Gaming and Video Streaming will eat up your battery power very fast and the laptops watt hour use does not include these activities.
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BatteryFuel is an eCommerce reseller, since 2002, of replacement batteries for laptops, cell-phones, camcorders, digital cameras and many more electronic devices. You can find many name brand replacement batteries and adapters like Acer, Apple, Compaq, Sony, Toshiba, Dell, Hewlett Packard HP at the online store.