Upgrade and Performance Evaluation of G8+ Large-size Cast Mono-Si Ingot

Abstract

With the rapid growth of CZ mono-Si solar cell technology in the global market, the development of cast mono-Si faces challenges in terms of crystal quality and cost. This study introduces the first preparation of a G8+ large-size casting furnace by upgrading a G7 furnace to enhance casting mono-Si's performance and economic benefits. The effects of the G8+ casting furnace on the preparation cost of mono-Si ingot, crystal quality and its impact on the performance of solar cells were thoroughly investigated. Modifying the thermal field and optimizing the seed pavement strategy increased the G8+ cast mono-Si ingot weight to 1600kg, raised the monocrystalline ratio to approximately 98%, and achieved an effective yield exceeding 50%. Solar cells made from G8+ cast mono-Si demonstrated electrical performance comparable to CZ mono-Si cells, achieving an average efficiency of 22.64% with only a 0.3% efficiency gap. Consequently, the upsizing of cast mono-Si ingots and adopting rigorous defect control strategies could significantly enhance the electrical performance and manufacturing productivity of cast mono-Si.