Other than the chance of it no longer having a charge when you would like to use it, I don't think there is a problem.
+1. I use Eneloops for camera flashes and Guitar and vocal wireless belt loops.Some of the newer rechargeables like Eneloop are pretty good about holding most of their charge while they're sitting around. They do lose a bit, but they're not all like the old rechargeables that would just keep discharging down to nothing over a fairly short time.
If you haven't tried any, I'd recommend Eneloop AAs for just about anything that takes 'em. They're all I've been using for several years, I use them every day, and I'm still happy with them.![]()
I wrote the month and year on the battery with a sharpie to remind me