The battery life of my DS3 is actually pretty good. Very rarely need to charge it, even when playing I was playing through Yakuza 4! :awesome:
It is weird how wireless controller battery life varies so much though. If I had to rate them by battery life alone it'd be:
Wavebird
Wii U Pro Controller
Wii Remote
DS3
Wii U Gamepad
DS4
Not sure how the Gamepad manages to outperform the DS4, seeing as it has 6" screen to continually power, but there you go.
Anyway, it's no big deal, I'll just treat the DS4 as a wired controller form now on.