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Hi guys (and girls?)! I'm new here, looks like a lovely forum!
I'm working on a project that is nearing completion, it's a solar powered self-driving car.
There's a li-ion battery bank of 1400Wh, 3 blocks in series which gives a nominal voltage of 11,1V.
We have a top flat surface area of about 1,5m², we were thinking to fill it with these cells:
Tests so far with these cells seem promising but only a small batch was tested.
Now we stumbled upon several questions regarding the solar panel:
1. Our top surface is flat and part of the structural integrity. We need the top to be somewhat forgiving so that it can flex a bit.
The rest of the structure is polyester glass fiber. It has to be able to withstand tough weather and vibration.
What options do we have for encapsulation? Is encapsulation with slygard with a plexiglass top good, or will the surface be too reflective? Will slygard stick properly to glassfiber/polyester? We'd rather not use glass to prevent brittleness.
Is epoxy (with a sanded surface for diffusing the light) a possibility?
The panels can not tilt and the surface has to stay flat so the coat has to diffuse the light, here in Belgium we are at 51° North. The next model might include tiltable panels.
2. Are the sunpower cells any good? We have ~520mm (20,5 inch) width and 3000mm length (~10 feet) available.
3. We are looking for a decent 300 watt MPPT charger to charge Li-ion 3S (11.1V nominal) banks, most seem made for lead acid batteries with slightly higher voltage. What would be a cheap solution?
I'm working on a project that is nearing completion, it's a solar powered self-driving car.
There's a li-ion battery bank of 1400Wh, 3 blocks in series which gives a nominal voltage of 11,1V.
We have a top flat surface area of about 1,5m², we were thinking to fill it with these cells:
Tests so far with these cells seem promising but only a small batch was tested.
Now we stumbled upon several questions regarding the solar panel:
1. Our top surface is flat and part of the structural integrity. We need the top to be somewhat forgiving so that it can flex a bit.
The rest of the structure is polyester glass fiber. It has to be able to withstand tough weather and vibration.
What options do we have for encapsulation? Is encapsulation with slygard with a plexiglass top good, or will the surface be too reflective? Will slygard stick properly to glassfiber/polyester? We'd rather not use glass to prevent brittleness.
Is epoxy (with a sanded surface for diffusing the light) a possibility?
The panels can not tilt and the surface has to stay flat so the coat has to diffuse the light, here in Belgium we are at 51° North. The next model might include tiltable panels.
2. Are the sunpower cells any good? We have ~520mm (20,5 inch) width and 3000mm length (~10 feet) available.
3. We are looking for a decent 300 watt MPPT charger to charge Li-ion 3S (11.1V nominal) banks, most seem made for lead acid batteries with slightly higher voltage. What would be a cheap solution?
There's also the fun of course in making something of your own that beats buying stuff too. 
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