How long will the new main battery power the laptop and How long does battery last? Battery run-time on a laptop is difficult to determine. Actual battery running time depends upon the power demands made by the equipment. The use of the screen, the hard drive and other accessories also results in an additional drain upon the battery, effectively reducing its running time. The total run-time of the battery is also dependent upon the design of the equipment. Generally, a new Hi-Capacity battery will run 30% to 50% longer than the old battery did when it was new.
The life span of a Notebook battery is about 1.5 to 3 years under normal conditions. As the rechargeable battery begins to die, the user will notice a decline in the running time of the battery.
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