How to caculate your Dell battery run time

Take care of your Dell Laptop Battery and ensure that it will be ready to work properly when you need it most. Some general tips for laptop care include: avoid extreme temperatures, don't leave a laptop outside in cold weather or leave it in a hot car. Cold laptop battery can't create very much power and hot laptop batteries will discharge very quickly. Use electrical power when available to keep Dell battery charged. Don't let your laptop go for long periods of time without using the Dell laptop battery.
You may also want to know how to caculate your Dell battery run time. 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 laptop 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 Dell Laptop Battery could power your laptop for 2.8 hours.
Laptop batteries have finite life spans. Whether you use the power cord and remove the battery it will lengthen the life of the Dell battery. Li-Ion laptop battery lifespan is approximately 1000 charge cycles, or 2-4 years under normal operating conditions.
Keeping the Dell battery in a cool place can prolong its life but not in a period of extended storage. The Li-ion battery should be stored at 40 percent rather than full-charge state.
The battery ages even if not used. For best results, keep the Dell battery cool. In addition, store the battery at a 40 percent charge level. Never fully charge or discharge the Dell laptop battery before storage. The 40 percent charge assures a stable condition even if self-discharge robs some of the battery's energy. If you are looking for other laptop accessories information, you can visit here: Compaq F4812A battery(14.8V )
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