Solar camping trailer to recharge ebike while overlanding

welcome teslanv!
as for the controller, i'm thinking about this one
https://www.amazon.de/gp/aw/d/B01DD1IRCU
..it is not real mppt and has some issues with resetting when the tracking error is big. but in DC-DC boost mode and given the price it might be just what i need anyway. lot's of coverage on youtube about it.

while moving i hope heat can be dissipated mainly from the top as there will be some airflow. also when stationary i want to tilt my trailer roof so the hot air will rise and provide some flow over the panel.
i expect gobi in spring to be fairly windy and rather cool. ..but yes, i am aware that the heat build-up in these panels will not be ideal for efficiency.

i'm still pursuing my idea of a coffin style camper on a single wheel. so frontal area creating wind resistance will be created by the "coffin" not so much by the flat panels. but gusts of side winds have to be expected to be pretty bad for stability..

at more than a meter wide they are already a little too big for my taste. so probably no chance to add padding but maybe a ridge around the structure to add stiffness and reduce danger of cutting myself or somebody else in case of an accident. political signs to recycle are non-existent here in china.. :lol: :roll:
 
If I was you I would avoid a charge controller completely. Simply serialize your solar panels to reach the voltage you want your batteries to be at a full charge. Your panels will pull the battery up to their in-the-sun voltage. You can serialize rather small solar panels (so long as the wire gauge is thick enough) to your large panels as a means to boost the voltage a few volts at a time until you reach the desired level.

Do you know about DC power converters? You might want one spitting out 5 volts to a USB cord if you plan on travelling with a cell-phone.

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with lithium you should be careful not to overcharge. so open circuit voltage of the panels should be close to full charge of the battery pack.
in my case that's 84Vs. i guess mixing different panels is not advantageous for efficiency either.
i thought about it too. but then it means a custom-made panel... :roll:
 
just found some panels that - when 4 of them are connected in series - would be toping at 86.8V and maximum power would be at 70.8V (400Wp combined).
actually not that bad. with DC-DC converter and display for the voltage (and lots of attention) it should be manageable.
 
for the cell phone i will get one of those little panels with usb port. maybe also usefull for balancing the battery pack.. :roll:
want to get a cheap usb volt meter to monitor the cell voltages from time to time.
 
Id definitely want a 12v plug, so you can tap that for various 12v devices, lighting, air pump, etc, as well as any usb device. About 5 ah of 12v battery would be very handy. When I tour, I carry a 12v lifepo4 pack to keep the tunes going, charge the phone, run a nice light in the tent, etc.
 
I found this accurate and reliable over a few weeks:
http://www.ebay.com.au/itm/151351164508?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

2x '12v' series panel sets in got close enough at Vmax (for my 52v charge), wasn't a huge boost, pretty efficient.

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some case and a voltage display would be nice for the converter.

meanwhile we could also start the building of my trailer... despite its lenght it will turn reasonably tight. and should handle offroad (slowly!) also okay.

torsional stiffness should come with another - wider - frame i put over wheels hight and by adding the walls for storage compartments.
 

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Mondo bob trailer. cool. I think you might find a smaller wheel will work fine.
 
http://m.spiegel.de/fotostrecke/fotostrecke-129072.html

guy in germany. living permanently in a bike trailer.
 
i think this one is not ideal for solar, because of the way it folds over. so alot of the time the panel would stand upright.
 
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