RadioShack 6V solar panel This is the most simplest way you can make a USB charger using a 6V solar panel. The finished product will be some what weather proof and requires no soldering at all. My solar panel was purchased from RadioShack with these specs: Typical power output : 1.5W Typical voltage output : 6V - 5% Typical current output : 250mA -5% Overall size : 129.8mm x 84.8mm x 3.2mm Because of the relatively small output current the solar panel can produce, it is recommended that this charger to be used to charge a power bank or a shut-down smartphone. If the charger is used to charge a power-up smartphone, the net current used for charging might not enough to charge the battery because the smartphone will consume most the the charging current. [25 NOV 2013] I conducted a simple experiment on how much the solar panel power will produce to fill up my 2600mAH power bank. For a full day of Sun, it fills up about a quarter of the power bank. I guess that's why commercial solar c...