Originally posted by Rosuav
Yes and no. Batteries have improved some (slower than the devices they power), but on the other hand, today's device often needs less power than yesterday's did, so the same battery will serve it better.
It seems like laptops have the same 2-4 hour battery life that they had 8+ years ago.

It seems to me that by now that number should be up to at least 12+ hours per charge.

While it is true that modern laptops use more power for their graphics cards and monitors, that increase is not terribly significant.

If batteries were improving like other technology (following Moore's Law as a minimum, a doubling every 24 months), then they should be 32 times more powerful than they were 8 years ago.

They aren't even close.