There are laptops that can last 7 - 10 hours, but most are not gaming laptops and that can only happen when not playing games. When playing games on battery at best you might get 2 hours worth of gaming.
The Dell XPS 15 1080p version with a quad core i5 / i7 and GTX 960m GPU can generally get 7 - 9 hours of battery life with "light" usage; meaning no games.
The high end Dell XPS 15 with the 4k resolution screen and 512GB SSD comes with a larger capacity battery (84WHr vs 56WHr), but only lasts on average around 6.5 hour base on reviews. 4K screen uses a lot of powerful compared to a 1080p screen.