So all parts for the Solar panels is now on its way to their new home. While waiting for the parts to arrive lets write a part 3 for this series after doing some more planing for the actual build.
So lets start with the BOM with prices.
- VIKOCELL TPE Solar Back Sheet (560mm x 5m) – 30$
- VIKOCELL Photovoltaic Solar Cells EVA Film Sheet (550mm x 5m) 34$
- 300pcs 0.12W 0.5V 0.24A 39x19mm Micro Solar Cells 38$
- Panel Solar Cell Welding Wire Strip kits 20m 1.8×0.16mm Tab Wire, 2m 5×0.2mm Bus Wire, 1 pcs 951 Flux Pen 16$
- Cover styren-akrylnitril (SAN) – NO NAME(400x600mm) 15$
Grand total: 133$
Yes, maybe a bit expensive, but the the material is sufficient for more than one custom build. I also have some backing diodes left on the list. But I save does for later.
I went for a cover made of plastic SAN. I found it in my local store and was quite pleased with the specs of it. Before I encapsulates the panel I will take the cover for a test spin and see how effective it is.
Here is the Characteristics:
Stiff with high stability
High softening point
Moldable with heat
High chemical resistance: withstand most fats, dilute acid solutions, oils and common bleach, some solvents and weak alkaline solutions.
Softening point:> 70 ° C ISO 306
Ignition temperature: 400 ° C DIN 51794
Decomposition temperature:> 270 ° C
Density: 1.08 g / cm³ ISO 1183
Fire Information: No flammable properties
Solubility: Insoluble in water. Soluble in aromatic solvents
Approved for food contact: FDA 21 CFR 181.32
Degradation Product: Monomer
Thickness tolerance at 20 ° C
1.5-2.5 mm: ± 10%
> 2.50 mm: ± 5%
Back to the solar cells. So I started to think about the layout and was not happy about that the BUS wire would end up in between each group in the panel. Destroying a nice layout. My goal was to have the entire 600x170mm panel with even spacing between all the the cells (Otherwise, I will not be able to stop thinking about the gap).
So I went back to the drawing board and came out with a pretty sweet layout that would give me even spacing and better performance overall.
In this layout I mounted the cells vertically which lead to that I could fit 120Cells instead of 108Cells. Also the performance of the entire Panel increased slightly. I could now get 20V, 14.8W. So I think This is the layout I will use.
For a more professorial look I think it is important that everything is straight and all spacing between cells are very even. So therfore I have started to design a template that I will 3D print and then use to fix the cell at soldering. I will simply place the cells in the template and no need for alignment 🙂
I also bought a better soldering iron today. I suppose there will be a lot of soldering in this project as we move further on.
Thats it for today. Tomorrow I will post the result of the first print!