Portable solar panel for charging a 48 volt battery

El3ctric_Biker

I have an electric bike with a 48 volt lithium ion battery pack. I am looking for a way to charge the batteries as I travel or when the bike is parked. I see there are lightweight flexible 12 volt panels I could carry, but the rest of the system is beyond my knowledge. I have found websites offering bike solar systems to charge laptops and phones, but not 48 volt. 

Estragon

The thing with charging the bike battery vs phones etc. is the total power (watt-hours) needed.  A phone might need 25wh to charge.  A bike battery might need 1000.  It would be hard to carry enough panel to charge that in a reasonable time.

For example, if you carried a 30w panel, it could take several days to charge.  In theory, you could series connect 12v panels to get the 48v, but you still have the problem of the size of panel vs the power you need.  There may also problems with controlling voltage to charge the battery properly.