Well, when I've come across a device that used little AA, and especially AAA, batteries that don't last worth a crap, I install a D-sized battery holder. Case in point? I have those LCD's digital weather stations, where a remote 433MHz TX operates outside for that temperature reading. I got tired of swapping AAA batteries in those every couple of month, even Li AAA's. So, I installed D-sized in place of that AAA holders. Looks like hell, but BFD, problem solved.