I want to buy an external battery for my laptop so it lasts longer without me having to keep on charging it.
I want to know the average battery life of the folowing laptop batteries are before they need charging:
Not enough information.
For example, what laptop are we talking about using these batteries in? What is the power draw of the laptop we are talking about?
For example... in a Toshiba A75, a 6600mAh battery will last approximately 2.5 hours, while a 4400mAh battery will last approximately 1.5 hours. This is a laptop with an Intel P4 3.2ghz processor, two cooling fans and a 15.6" widescreen LCD. If the processor were slower, the screen was smaller, and there was only one cooling fan, these batteries would last longer. If the processor were newer, utilizing better power saving technologies, the batteries would last longer.
So, without more specific details as to where these batteries would be used, it is impossible to say how long they would last.
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