Firstly, you may be wondering why you would want to split a solar cell into two? There are two primary reasons, one to boost voltage with a limited number of cells or area and the second is if you have broken cells and you wish to cut the broken side off and still make use of the undamaged side.

When you need to boost the voltage output of your homemade solar panel and you do not want to buy a voltage regulator, you could try splitting your solar cells into two. With two halves of a 0.5V cell, you can connect them in series and get a voltage output of 1V. All that happens is your power output from the original cell is divided in two as well, so you will be left with two 0.5V 2W cells from one original 0.5V 4W cell.

Solar cells are not damaged by cutting them in half. As long as you retain the full tabs on the front and back of the cell, the divided cells with still produce the full voltage. This means that a solar cell can only be divided along lines parallel to the tab lines and can only be divided by the number of tabs. For example, if you have a double tabbed cell, you can split it into two while if you have a triple tabbed cell, you can split it into three smaller cells.

Step 1: What You Will Need

Anyone who has worked with solar cells knows that they are extremely fragile, even a small bump or nick can cause them to break in half. So you need to be extremely careful when cutting a solar cell into two.

What You Will Need:

A Solar Cell (With at Least 2 Tabs)
A Ruler
A Sharp Craft Knife

You cannot cut a cell which has been laminated in any way. The cells need to be bare and uncovered, ie this doesn't work will glass cells.

Step 2: Cutting the Cell

To cut the cell, place the cell face down on a clean and flat surface. It is important that there are no high spots, pieces of dirt of metal on the surface as these may cause the cell to crack when you put pressure on it.

Place the ruler down the centre line along where you wish to split the cell. Now repeatedly run the craft knife lightly along the edge of the ruler. Do not apply too much pressure or the cell will crack. Do this until you feel parts of the cell splitting underneath the knife (the knife movement will become slightly jerky). Lift the ruler and break the cell in half along the line. The idea is to gently score the cell over and over so that you encourage it to "break" along your line. You are not actually cutting through the material.

The video below shows how to do it in detail as well as the voltage measurements before and after to verify that the cells still work:

Step 3: Test the Cell

Finally, test the cell to check that it still produces the correct voltage.

In this case, the original cell was a 0.5V cell and the cell still produces just under 0.4V but this is indoors without direct sun. In direct sun, the cell will still produce the full 0.5V.

You can now use the split cells to build your own panel. This article covers selecting the cell configuration, tabbing your cells and then assembling them into a working solar panel.