Hey. I've been running two 12V squirrel fans in my helmet for a while now. Both are in their own individual circuits consisting of a 9V battery and two AA batteries to make up the 12V. I'm wondering if there's another method of powering them seeing as my current set-up is pretty bulky and heavy, leaving me pretty cramped in my helmet and doing terrible terrible things for my neck. Also, constantly buying sets of four AAs and two 9Vs in addition to all the other batteries I buy for the other electronics can get costly. The plan is to get the same longevity; as in trooping a whole day in them without them dying on me, and also the same fan speed. I originally had only one 9V battery per fan and it wasn't that effective at keeping me cool. I felt a big difference when I upgraded to a 12V system.
I've looked into watch batteries and those smaller 12V AA-like batteries, but neither would last the whole day.