Analysis of Series Resistance Effects in Current Solar Cell Technologies

Sunpower’s IBC MAXEON III solar cells, composed of three subcells connected in parallel, are studied using a custom-designed PCB prototype adapted for back-contact measurement. The PCB includes metal strips inspired by old 3R12 batteries to ensure solid contact. In addition, the prototype consists of six jumpers, connected just before the cell connection pads allowing selective disconnection to simulate contact faults. EL images are obtained, when injecting 4 A to the cells and two scenarios were tested: in Scenario A, pad 3 (input of subcell) was disconnected, resulting in partially disconnection of subcell; in Scenario B, pads 3 and 4 were disconnected, complete disconnection of one of the subcells leading to minimal leakage current.