Transferability of the light-soaking benefits on silicon heterojunction cells to modules

TL;DR

This study examines how light soaking and electric bias treatments improve silicon heterojunction solar cells and modules, revealing that lamination resets some benefits but a post-lamination treatment can maximize module performance.

Contribution

It demonstrates that a single post-lamination treatment suffices to optimize module performance, simplifying the process compared to pre-treatment of cells.

Findings

Lamination can reset light soaking benefits.

Post-lamination treatment restores performance gains.

Modules respond better to light soaking than cells.

Abstract

We investigate the effect of light soaking and forward electric bias treatment on SHJ solar cells and modules, and in particular the influence of the thermal treatment occurring during lamination. A substantial performance increase is observed after electric bias or light soaking, which is shown to be potentially partly reset by the lamination process. This reset is reproduced by annealing the cells with the same thermal budget. A second treatment after lamination again improves performances, and a similar final performance is reached independently of the pre-lamination treatment. Therefore, a single treatment after lamination enables maximal module output without any benefit from a cell pre-treatment. Whereas cells react overall better to forward bias, modules show a slightly better response to light soaking.