I did a lot of battery analysis back at the lab for portable and remote monitoring systems. Expanding on that with recent results from NiMH cells, here is a quick summary:
Standard name-brand alkaline batteries do amazingly well, and can last a very long time in low drain or intermittent duty applications. The Duracell AA is rated for 2850 mA hours. You can estimate the operating life if you know your current drain and duty cycle.
The Energizer L91 AA lithium cells had the highest energy density available to consumers back when I did the study. While the rated capacity is not much higher than the best alkaline cells, they will do much better than alkalines in high pulse current applications, such as electronic flashes, and probably remote controls such as the Icon.
For my own use I am converting to the Sanyo Eneloop for low-drain or intermittent duty cycle applications, such as remotes or digital cameras. Their self-discharge rate is VERY low, and they will last a long time in remote controls. I use them in our Icon.
For high current applications and continuous moderate drain where long operating life is important, such as a handheld GPS, I like the 2700 mA hour Sanyo AA NiMH. Their self-discharge is pretty fast, but after a quick top-off before being installed, you can’t beat their capacity. I have never had them die in my GPS even on an all day hike.
A good charger is important. I highly recommend the La Crosse BC-900. Its test and refresh modes are particularly useful in determining when cells should be retired. Rechargeable cells do go bad, often much faster than the 500 or 1000 cycles touted by the manufacturers. However, even at 10 cycles, NiMH cells are more cost effective than disposable alkalines. And at 100 cycles, you are way ahead.
Jeff
