Low-Cost Metallization Based on Ag/Cu Fingers for Exceeding 25% Efficiency in Industrial Silicon Heterojunction Solar Cells

Although Ag-coated Cu technology is considered to be an effective approach to mitigate the metallization expenses associated with silicon heterojunction (SHJ) solar cells, there is limited reporting on the photovoltaic performance and reliability of devices employing Ag/Cu electrodes. Herein, industrial SHJ solar cells were successfully fabricated, yielding an average efficiency of 25.18% with bifacial Ag/Cu fingers, which caused a 0.13% decline in efficiency but saved 46% in Ag consumption when compared to traditional Ag fingers. Performance degradation is demonstrated to originate essentially from the front rather than rear Ag/Cu fingers, as revealed by a comprehensive analysis of resistances enhancement and optical losses. Notably, the Ag/Cu fingers exhibited 1.4% lower printed qualification rate and similar high-temperature stabilities in contrast to Ag fingers. In the results, valuable insights were provided for further optimization of low-cost and high-efficiency SHJ solar cells based on Ag/Cu electrodes. Herein, the application of Ag/Cu fingers to industrial silicon heterojunction (SHJ) solar cells with Ag fingers serving as a reference, obtaining an average efficiency of 25.18% and a 46% decline in Ag consumption, is explored. The optical and electrical roles of the Ag/Cu fingers are reported separately to verify the contribution of the front and rear sides. image (c) 2024 WILEY-VCH GmbH