Here's an update.
I got one of these, straight from Hong Kong, with free shipping. That link is a 'buy it now' for $23.99, I got the identical item in an auction for USD$19.50 This does not have a light like many do. The capacity of 5000 mAh is larger than many.
In reading lots of
reviews about this type of thing in general, a lot of people complained about them working poorly. They would get them, plug their phone/whatever into them, and put it in the sun.
Several reviewers that seemed more knowledgeable pointed out that most any kind of these should be fully charged by USB, then discharged (by charging your other gadgets), and cycled a few times like this, before using the solar charging part.
This one has four LEDs that blink to show the charge level, and if you push a button, apparently show the amount left. There were no instructions with this.
After I had charged/discharged it three times, I put it in the sun, totally discharged. This was after 2 PM, the first week of November in Midwest USA, not exactly a powerhouse of a time for sun. It was mildly overcast at that. I propped one end up a bit to be pointed a little more towards the sun instead of just straight up. I was pleasantly surprised to see that after about 5 hours, it showed about 50% charge. Most
devices like this say that it takes nearly a full day of sun for a full charge, so I thought that was not too bad, for an overcast early fall day.
So, for about $20? I consider it a good deal. I am planning to get another/similar type of solar battery as well. I will have several phones/cameras/PVs to keep charged and my group will be totally away from any AC power for about 9 days. I will try to get a better one, for comparison. I see some that have a handle/loop that you can put a carabiner on, that might be convenient. There are also some that have a second solar panel, that will charge the original battery up faster.
