This thesis discusses the development of a device suited for controlled bending of solar cells. When the solar cells bend, mechanical stress appears in it, causing reversible and irreversible changes, such as cracking of the material or contact layers. These changes can be detected by various diagnostic techniques such as electro- and photoluminescence. The presented device performes repeatable loading of a solar cell up to a predefined radius and force all the way to the breakage of the solar cell while performing measurements. The device consists of a lifting part and a solar cell mount. The lifting part contains a lifting guide with a position encoder and a measuring cell for measuring the force. The lifting guide lifts the tool, which acts directly on the solar cell.
The device bends the solar cell in a controlled manner, observing the cell's responses to a certain distance or force. A preliminary test of the device on a square-shaped polycrystalline solar cell with the dimension of 156 mm x 156 mm was successful. The measurements showed that the solar cell can withstand mechanical loads of up to 6 N or displacements of up to 45 mm, with electroluminescent images showing the gradual formation of cracks.
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