by john jeffery » Mon May 03, 2010 6:08 pm
At last the new 4 cell modules are on their way! The first shipment is scheduled to leave China on the the 15th of May so I should have them a few days after that.
They are being made on the same backing as the 3 cell modules, that is, black fibreglass 62mm x 120mm x 3mm with large square solder pads on the back. They are made from the same first quality, laser etched and anti-reflective coated cells, about 16+% efficiency, FF 0.75+.
Despite being 4 cells they actually take up more of the available space. Unfortunately because there is a bit more active material plus the extra handling in mounting the extra cell they are going to cost me a dollar or two more.
The good news is that you will probably only need to use 8 modules rather than 10. This will make for a smaller, lighter panel and require less ballast for those capable of building small, efficient, light weight cars.
To approximate the module voltages multiply by 4/3 (so 8 modules will give a bit more voltage).
To approximate the module currents multiply by 4/5.
To approximate the module power multiply by 16/15.
Full test data will be available as soon as I can get proper tests done.
For the power freaks, you can use 10 modules and still stay under the 25Voc limit.