The LiPo Rider can be used to charge a LiPo-Cell
using a 4.8-6.5 Volts Solarcell or using a USB cable.
The saved energy can be taken from the solar lipo charger through a USB-Port using the integrated Step-Up Converter
Additionally it has an On/Off switch for Output Voltage
4.8-6.5V Solarcell voltage
up to 400mA Carging current
up to 350mA Output current @ 5 V
under 100mV Ripple voltage @ 300mA
Size:: 47*37.5*6.6 (mm)
The LiPo Rider can be bought at the Manufacturer and costs ~10$
Theres is also a bigger version, the LiPo Rider Pro, capable of 1A output current.