Thanks you guys for the advice so far. I've just spent the last two hours pouring over amazon reviews, and I am completely overwhelmed. I feel like I'm trying to learn how to build an ar15 for the very first time, trying to figure out parts and brands and compatible this and that.
Reviews speak highly of the (new made in Japan) amazon basics black AA and AAAs, but the white-wrapped ones have a longer lifespan in exchange for shorter output duration. The Panasonics get favorable reviews but are more expensive. Then there is all the made in China garbage to have to wade through and filter out. The Sanyos look good too. A few bucks per pack of batteries isn't much, but then there's the C and D cell adapters, C and D cell double adapters, and now suddenly I need three times as many AA batteries as I had anticipated, unless I get C and D cell batteries specifically, but there are a hundred more AA/AAA chargers than there are AA/AAA/C/D chargers.
The chargers.... Holy balls, the chargers. Trickle, fast, pulse, LCD display, "intelligent," blank, Chinese fire hazards, >$100 units.... Man alive.
Then to complicate things I also need 9v and CR123 rechargeables, with the latter of course blowing out bulbs in LED flashlights every other review or so.
I had no idea buying batteries was going to be this complicated.