Perhaps not quite the same thing but I have a Galaxy S Smartphone. I let it run right down until it switches itself off and then put on charge overnight so that it achives 100% and .. Then repeat the process when required. With that I have achieved seven and a half days of use. That is also my understanding with regard to my Samsung RV711 laptop purchased today and which I shall be trying out. Don't know if that bit of info helps?
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