I have several devices (two way radios, a gps, a graphing calculator, and a camera) that burn thru batteries and quit when they discharge below 1.4 volts. Hence they don't use rechargeables like enloops, at least not for long. So I end up with piles of alkaline batteries with quite a bit of charge. And a lot of rechargeables with no use.

Suggestions? There is only so many flashlights I can use at one time the DO take the weaker batteries. Is there some sort of " Joule Thief "
for AA's that would fit in devices?