I'm a big fan of Rechargeable AA batteries but under a few conditions. They have to 'stay charged' even when sitting around a few weeks or even a few months. They also have to perform longer than your average battery, so less swapping through the day. This is why I built up an inventory of Sanyo Eneloop rechargeable batteries and have been using them in heavy rotation. The problem of course is these things aren't cheap.
Sanyo Eneloop 8PK AA Rechargeable Batteries
Aside from all the camera accessories such as LED lights, portable audio recorders, and wireless mic packs, they have found their way into my home inside wireless mice, wireless keyboards, television remote controls, XBOX and Wii controllers. There just doesn't seem to be enough to go around these days, and looking to buy more I turned to AmazonBasics Rechargeable AA Batteries. With almost exact performance as the Sanyo Eneloops but at maybe 33% or so cheaper.
(5) AmazonBasics Rechargeable AA batteries in F&V Z96 LED Light
I'm still using my Sanyo chargers to recharge these batteries, so if you're already invested in Sanyo Eneloops these will fit seamlessly into your workflow. I've been very happy so far, but don't take my word. There are tons of reviews and customers performing extensive tests against the Eneloops. It would be my suggestion that you look into these batteries before pricing steadily climbs (find them here).
AmazonBasics AA Rechargeable Batteries