I have 2 main laptops:
I'm sort of okay with the battery for both, my MacBook lasts me almost an entire workday on battery, especially if I switch to SublimeText which is very light on the battery and ease down on npm processing commands.
The DELL only lasts 3,5 to 4 hours, I could probably extend that if I disabled some features, but I don't want to mess around with that. I don't use that one for when I need long battery life, I use it more as a replacement for a desktop since I don't want a big computer to take up space. The Dell has build in 960M NVidia and 4K screen which I believe is heavy for the battery. I do have the portable extra battery from DELL though, so I think I can extend it to 6-7 hours with that.