John AE5X has a great article, “Batteries and QRP” on his nicely-designed website. Using a West Mountain Radio “Computerized Battery Analyzer II” and a Fluke 87 multimeter, he simulated conditions that batteries would normally operate under in portable/mobile conditions. The battery types he tested include:

• AA cells of different chemistries,
• lithium-polymer rechargeable batteries, and
• gel cells.