You can't add up mAh and compare like that. Or you can, but only if the voltage is the same.

Let's say you have those nice 2000mAh AA at 1.5 volts, (it's slightly below 1.5v, but it doesn't matter). Put two of those in your GPS, and now you have a two cell (two AA's) battery pack, rated at 3 volts. But that 3 volt package still holds 2000 mAh -- NOT 4000. Same mAh, twice the energy content, because the voltage is doubled.

I guess the batteries inside the Morphie powerstation is about 3.7 volts (that's fairly typical for lithium based rechargeable batteries). That's roughly the energy content of somewhere between 6 and 9 of your 2000 mAh AA's at 1.5 volt.

ahh, my bad. When the GZ website indicated 9200 mAh it also stated at 1.2 volts which would be different than the 6000 mAh at the Mophie's unspecified voltage, but it's safe to assume it's higher than 1.2 volts.

These figure do not tell the whole story.
The voltage of a battery or cell is as important as the mah capacity. The Mophie powerstation is said to be 6000mah, at a voltage not specified but probably 3.7 volts from a single lithium ion cell.

AA rechargeable cells are typically 1.2 volts each, or 4.8 volts for 4 in series.

6000 mah at 3.7 volts is a lot more energy than 4.8 volts at 2000 mah.

Yep, MostlyHarmless pointed that out yesterday -- upthread a couple posts. The Mophie Powerstation looks like a good piece of gear for those without reliable sun.

I'm a big fan of the Waka Waka Power for a compact phone recharging solution that has excellent solar capability. I was a Kickstarter backer of it but otherwise have no affiliation.