To test the battery today we put the machine through three sets of real world situations. One as a media movie lover on the move, a person wanting to watch HD media on a train journey or bus with two thirds screen brightness (any less and quality suffers). Secondly as a business man, using the machine for productivity with wireless enabled and balanced power settings with a mid way (around half) brightness setting. Thirdly as a gamer on the move, with the nVidia solution fully active and screen brightness up high.
The 7800 mAh/87Wh, 9 cell battery is capable of keeping the machine alive for many hours under normal conditions, although when gaming you can expect the battery to be about to give up around the 1 hr and 30 minutes mark.