In Part 4 of our solar module microcrack series, CEA's Paul Wormser dives into the ways that microcracks occur during the solar cell and solar panel manufacturing process.

Video Transcript

There are quite a number of steps in manufacturing modules. And one of the most critical steps to get exactly right is the solar cell to solar cell interconnection, where you're soldering electrical connections and mechanical wires between cells.

In this case, in order to melt the solder, to get that connection, you have to really raise the temperature, and that causes thermal stress on the wafer and on the cell. If that stress is not managed well, if that temperature heating profile is not managed well, you can cause enough thermal stress that you disrupt the structure of the wafer underneath, and you actually can cause permanent damage to that wafer.

You can't see it. And it's very small, but it's pretty significant. And this is really what we call the microcrack. So it happens due to a thermal disruption, usually at the interconnect machine.

Watch Part 5, How Can Buyers Visually Inspect For Solar Module Microcracks here.