adding a small solar panel?

Those tiny trickle charger

Not worth bothering with! What ever it push back into the battery all day will be used up in a few seconds.

Nice setup! Idea is great! The down side . it won't recover much due to its size and location! Another down side, solar panel has a peak output up to 50+ volts requires a regulator, if that regulator fails, it could supply high voltage to sensitive electronics !

 

i glued one to my roof, and i'm running 67% ev.

 

Very true, it's excessively slow, but in my eyes it's capturing energy over a long period of time, that would have been wasted anyway. Luckily I wired it so that the panels cannot exceed 5V, but at excessive high produces 2.8A outside of the car in direct sunlight. Considering the panels are behind glass/tinting and inside the car, it's a realistic 400mA. In this case there's no voltage regulator (insert EE whining sound), and it's attached to a lamo 5V usb battery. The entire setup weighs under 1 pound and the waste energy gathered into the battery feeds my wife's phone and tablet. If I have passengers it feeds them in the back as well.

 

Djdawn can you please tell me what you bought and how you wired it to charge a usb thingy? I would love something like that as I could use some free energy to charge my phone!

 

Unfortunately the guy that I bought the panels from no longer sells them, and other sellers imo have them at an ureasonable price. However if you're interested, here's one guy that has them.
3W 5V Solar Panel 600mA 120 180mm Monocrystalline Pet Solar Cell w USB Cable | eBay
Assuming you bought 5, wired in parallel, following this pic:

It would produce 5V with 2500mA at excessive ideal peak. Considering the panels will be behind glass, they'll be about ~20% as effective. I wired a female usb socket to one end of it and used the power coming in to charge a usb battery. Not all usb batteries will charge with the massively small and varying amperage, but through trial and error I found a 16000mAh external battery that would charge with as little as 100mA. Frys has one with the flag on them periodically on sale for $20. Link of that model below:
MEGA 16800 mAh LCD Powerbank

I'd like to point out that since upgrading my tinting from weird purple to metallic tinting, the rear solars produced ~10mA, essentially nothing. I've eventually moved them to the house and they, combined with other solars, were immensely move productive there.

 

Thank you very much for your detailed instructions for helping me realize my green dreams! I'm gonna bookmark this and get this project started in the summer!

 

Its possible. I have shell cis 2inch glass solar panels that output 5 volts at 100ma. By putting 60 cells in series =300vdc . The panel would be 120 inches . Now you can reconfigure the shape into a square or rectangle for a smaller area. . With blocking diodes a constant trickle charge thru long periods would maintain the battery voltage even though the current is minute there will be current flow and the voltage will be higher than the battery and that is what will keep the voltage up.. the shell cells are sold in boxes of 170 for about 60 dollars. Look for CIS shell solar cells.