I bought this 30 000mAh solar USB battery from TinyDeal.com
I'm sceptical about the 30 00mAh, so I'll be undoing the screws in the next few weeks to check out what the actual power cells have written on them. Other sites are selling 3000mAH batteries for more, without the solar panel.
When I first charged the powerbank overnight, the power LEDs wouldn't switch off. It was crazy, they stayed on for days. However, once I charged it even longer, and then put the powerbank in the Sun for the solar battery to charge it, the power LEDs went off when it was out of the sunlight. It looks like it just needed to be filled with enough charge to behave normally.
Now the LEDS flash when its in the Sun, when its connected to the mains, and when its recharging my phone. They now switch off when I hit the "off" switch, as they should. The built-in solar panel delivers 1.5 W.
Its very light, so I carry it in my backpack at all times, and always have it available to recharge my phone. It comes with a 2A and a 1A USB port. The phone recharges in AC mode, so its pretty quick. T
he only down-side is that the LEDs are very bright when the powerbank is recharging my phone. It also comes with a super-bright LED to work as a torch. I bought mine for just $20!
At home I've teamed it up with a 7.5 W fold-out solar panel to speed up the solar recharging time. With my extra solar panel I can recharge in a day of full sunlight, or a few days of indirect sunlight.