Do you have a favorite brand of batteries? ( mostly aa/ aaa)
I've heard good things about energizer universal

Eneloops have been very good to me. Amazon's house brand have not proven to work as well for my uses. I haven't tried any other brands recently.

Most of my batteries are Eneloops, most date back from 2008 and 2009. Used in everything from flashlights, headlights, radio's to computermouses. They just keep on going.

It's Eneloops and lithium primaries for me.

Another vote for Eneloops - very satisfactory and much cheaper in the long run than alkalines.

For NiMH rechargeables, you should just get Eneloops and not worry about the rest. If you can't find those, pick up some Eneloops, or possibly some Eneloops.

For LiIon Rechargeables, I bought some AW brand protected 14500 batteries many years ago. Those are still going strong and I highly recommend them. Recently, I bough some NiteCore brand 18650's and those seem very good, but I've only been using them for a few months. I'm sure they are from some other manufacturer and rebranded. But I don't know who. They are 3400mAh protected LiIon rechargeables. Lots of capacity there. I hope they last long. I predict they will, and hope I'm right in that prediction.

I use Eneloops for AA / AAA, and Panasonic 3400mah protected 18650s for my flashlights along with a Nitecore Intellicharger i4 to charge both

Seriously, I'm amazed more people don't know about Eneloops. This is good, cheap technology, saves money in the long run, and it reduces toxic waste. What's not to like?