I haven't had good luck with AA "emergency" chargers or AA Solar Chargers at all. The 2xAA emergency Cell Phone chargers get really got when I try to charge my Android phone. I have a 4000mah Solar/Lithium Charger that's 4.5 x 3.3 x .5. It can charge my Android up from empty 4 to 5 times, and will charge my IPAD from empty to around 50% without melting down.

It does have a built in Solar Cell, but it would have to sit out in the direct sun all day long to get any type of usable charge. It does work well for "topping" off the battery in the unit however.

The device is made by Opteka, It's model BP-SC4000. Unfortunately, it doesn't charge AA/AAA batteries directly. But it's light enough that it works well for most all my other EDC electronics that I carry. It's about $25.