Contact, Characterisation, Characterization, Solar Cell, Busbarless, Probe bar
Summary / Abstract:
A novel contacting system with Flexible Spring Suspension (FSS) has been developed. The system is optimized for the current-voltage (I-V) curve measurement of busbar-less silicon solar cells and is also suitable for other structures such as multi-busbar and shingled solar cells. It is equipped with independent current and voltage contacts on the fingers, in order to achieve ideal 4-wire connection. The contacting structures of the FSS4 consist of multiple small reed-shaped strips, thereby realize more secure and reproducible contact to the fingers with low contact resistance than conventional pin probes. Excellent reproducibility of relative ±0.05% or better in the Isc, Voc, Pmax, and FF has been confirmed for 20 times of dynamic testing of a 6-inch busbar-less cell, which includes mounting/unmounting of the cell to the sample stage and connecting/removing of the FSS4 system to the cell. Undesirable damages to the fingers and cells during the measurements are minimized by the FSS4, because of its innovative structure where each strip has perpendicular contact to the fingers by monolithic plate spring suspentions, and also its line contact to the fingers. It also has an excellent mechanical durability of over 10 million times. In the actual production line conditions, reliability of 4 million times is expected, which enabling low-cost and reproducible production. tual production line conditions, reliability of 4 million times is possible, which enables low-cost and accurate production.