Instructables

Step 1: Buy some solar cells

I bought a couple of bricks of 3 X 6 mono-crystalline solar cells. It takes a total of 36 of these type solar cells wired in series to make a panel. Each cell produces about 1/2 Volt. 36 in series would give about 18 volts which would be good for charging 12 volt batteries. (Yes, you really need that high a Voltage to effectively charge 12 Volt batteries) This type of solar cell is as thin as paper and as brittle and fragile as glass. They are very easily damaged. The Ebay seller of these solar cells dips stacks of 18 in wax to stabilize them and make it easier to ship them without damaging them. The wax is quite a pain to remove though. If you can, find cells for sale that aren't dipped in wax. Keep in mind though that they may suffer some more damage in shipping. Notice that these cells have metal tabs on them. You want cells with tabs on them. You are already going to have to do a lot of soldering to build a panel from tabbed solar cells. If you buy cells without tabs, it will at least double the amount of soldering you have to do. So pay extra for tabbed cells.

I also bought a couple of lots of cells that weren't dipped in wax from another Ebay seller. These cells came packed in a plastic box. They rattled around in the box and got a little chipped up on the edges and corners. Minor chips don't really matter too much. They won't reduce the cell's output enough to worry about. These are all blemished and factory seconds anyway. The main reason solar cells get rejected is for chips. So what's another chip or two? All together I bought enough cells to make 2 panels. I knew I'd probably break or otherwise ruin at least a few during construction, so I bought extras.
 
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rashaism16 days ago

thank you for this very nice project...

I want to ask you if i want to buy the solar cell what must be its power?

warren43213 years ago
For the latest update on DIY solar cells you can refer to http://www.buysolarpanelweb.com
king70703 years ago
i want to buy 3 X 6 mono-crystalline solar cells !!! please tell me the web site where i can buy these cells . i am waiting for your's reply
speedstix4 years ago
 Hello, very nice my group and I did the exact same thing for a final year project. We actually made a Maximum Power Point Tracker for solar panels. I wanted to clear something up in step 1. Yes it is true that you need a voltage higher than 12 V to charge a batter (assuming lead acid here) but keep in mind that the panels themselves will only produce a higher voltage IF the load permits. This means that if the battery requires 14.4 V to get charged the panels will operate at that voltage. You have no control over that. Also if say those panels are at that point you might not be getting the maximum power from them. Check out a Maximum Power Point Tracker and you will see why. Here is a typical current vs voltage and power vs voltage curve of a typical solar panel. Typical curve keep in mind that the panel can operate anywhere from 0V to 18V. Somewhere at that voltage you will get maximum power. It was a really cool project, we were able to extract 10% more power using our circuit then without using it. 

suzylennox4 years ago
If you are looking for a source in the UK, you can buy direct from Sharp. Their minimum order quantity is 40kg. Cells are damged and are classified as either potential halves (£60 per kg) or potential quarters (£45 per kg) depending on how much undamaged cell is available. If you want further details email suzy.lennox@sharp.eu
Valence_45 years ago
Go to eBay and write, in the search box, "Photovoltaic" or "solar cells".
thank  u  V
sspence5 years ago
What ebay sellers did you get these from?