Solar Cell Interconnector Design

Various solar cell interconnector designs are analyzed for fatigue failures under extended temperature cycling. Test results are presented for several configurations. The stresses and failures of the solder joint between interconnector and silicon cell are discussed in light of test results, new long-term cycling data showing much greater incipient failures than previously expected based on extrapolation. Data are also presented for solder creep strength at elevated temperatures. A comparison between soldered and welded joints shows that both approaches have their weaknesses. The bonding method of cells to substrate must be integrated with the interconnector design to obtain optimum performance, mechanically as well as electrically.