u/GNX63

I have a garage door opener hanging on the side of my house to get into my garage. It's basically a remote. It is not wired to anything and it takes two AAA batteries. I've tried rechargeable Eneloops in it but they don't seem to function well. They don't seem to last long but, oddly, when I charge them, they don't take many amps before the charger says they are full. Couple questions: Should Envelops work okay outside? If not, what is the best battery for this type of use? Reading online, it seems as though some standard (not rechargeable) lithium batteries would be best. Looking for some insight. I need this unit to be more reliable than it is given that the batteries seem to go very quick under very little use. TIA