Originally Posted by jeff-o
Short answer: No. Invest in some 2700mAh NiMH rechargeable AA batteries (10 of them, to make 12V).
I tried sets of 12 AA 2500mah batteries and sets of 14 with a 20watt MR16. They worked very brightly for a short period of time. At 2500mah the math promises over an hour burn time but I didn't even get 30 minutes worth. This was even the case when I hooked up a LightBrain controller that evens the effective voltage to 13.2v.