A large-volume manufacturing of multi-crystalline silicon solar cells with 18.8% efficiency incorporating practical advanced technologies†
The optimization processes for the mass-production of high-efficiency multi-crystalline silicon solar cells have been observed in this paper. After incorporating several practical advanced technologies such as grain-size controlled low defect-density mc-Si casting ingot, precisely aligned selective emitter, surface-damage free reactive ion etch texturing on a mass production line, the total-area efficiencies up to 18.84% and a production average efficiency of 18.65% for large size (156 × 156 mm2) multi-crystalline silicon (mc-Si) solar cells have been demonstrated, equating to an absolute efficiency gain of 1.58% compared to a conventional solar cell. The corresponding module power is 270.3 W, a 20 W increase over a conventional 60-cell mc-Si module of the same dimensions. These results demonstrate a successful transfer of advanced techniques from laboratory to large scale industrial production, which promote the mc-Si solar cells taking a big step forward in solar cells applications.