10 second screen dim takes 90 seconds/battery life

Regarding battery life, I sometimes like to switch music a lot and explore, listening to 30 seconds here and there. As I do so, the battery drains on the controller really fast, like in a half hour or less. Is this normal battery life?

To increase battery time when I'm listening without surfing around, I set the screen dim to 10 seconds, but it takes 90 seconds, even when I put the controller down on the table. I tried to increase the number, and it took even longer. Is there a way to get the controller to dim more quickly?

Thanks!