AA batteries look pretty much the same. But there are so many kinds: lithium, nickel-metal hybride, nickel oxyhydroxide, and alkaline. Shopsmart magazine tested 17 AA batteries, both rechargeable and regular, here are their results. 
Best Rechargeable Batteries:
- Duracell rechargeable – Thes nickel-metal hybride batteries can be recharged hundreds of times.
- Duracell precharged rechargeable – Unlike other rechargeables, you can use these without having to charge them up first. So they’re good to go right out of the box.
Best for Digital Cameras:
- Energizer Ultimate Lithium – In digital cameras these lithium batteries took the most snapshots at the best value.
Best for Toys and Flashlights:
- Kirkland Signature – These alkaline batteries are cheap and have a long shelf life. Costco sells them in packs of 48.