If your battery uses AAA-sized cells, get rid of it.

These tiny cells just can't reliably deliver the kind of current your servos will be drawing with hard-core 3D stuff and you will eventually experience a failure (don't ask how I know :-)

A *much* better option is a battery built from the 2/3A sized GP1100 hi-current cells. I get mine from Radical RC and they're bloody marvelous. My Mojo 60 has two 5925 high-speed digitals on the tail and two S3010s on ailerons. The GP1100-based 5-cell pack gives me easily 40 minutes of reliable flying between charges with plenty of capacity in reserve.

Being a high-current cell, these batteries will also take a fast field charge so you can top them up for 10 minutes after every third or fourth flight and fly all day.