Improvement of silicon heterojunction module efficiency using fast illumination post-treatments

Intense illumination treatments on silicon heterojunction cells (SHJ) have recently gained interest to improve the final cell efficiency and are now being implemented into cell manufacturing tools. However, additional efforts are still required to clarify the robustness of such approach. Indeed, it has been reported that the positive effects of the intense illumination treatments applied to cells may be partly lost during module assembly. Therefore, in order to circumvent these potential issues, we reveal herein a broad investigation on the interest of intense illumination treatments directly at module level, using an experimental lab tool provided by Applied Materials, Baccini (Italy). Efficiency gains up to +0.3 %abs have been achieved within a treatment process time compatible with industry requirements. The gains remained stable for two months after a slight decrease during the first days (−0.05 %abs). Moreover, the reliability tests against UV, thermal cycling and damp heat did not reveal any detrimental influence of the post-treatments applied to the modules, further highlighting the fast illumination post-treatment as promising candidate for the next generation of high technologically advanced photovoltaic modules manufacturing production lines. •Post-treatments on modules with a LED-based post-treatment prototype has been studied.•+ 0.3 %abs. efficiency gain is achieved on modules within industry-compatible timeframes, against +0.5 %abs on sister sells (difference are discussed).•The gain is shown to be mostly (75%) stable after a slight initial destabilization.•No warning is reported on the reliability of the treated minimodules•Other beneficial side effects of the post-treatment are illustrated and discussed.