I use Gerbing heated gloves, but the battery's pretty new, so is working well at the moment. I have had problems with older batteries draining on other bikes though.
The gloves are brilliant if you ride all year, they keep your hands warm all round, not just the palms. Also, Gerbing will replace the gloves if they pack up, no matter how old, and they're warm enough to wear without plugging in at the moment.
Highly recommended!