Post-Metallization Passivated Edge Technology (PET) for Bifacial Silicon Shingle Solar Cells - pSPEERPET

We present results in post-metallization “passivated edge technology” (PET) and its application on bifacial p-type silicon shingle solar cells. Host cells (full cells with shingle metallization layout after contact firing) separated by either thermal laser separation (TLS) or conventional laser scribe and mechanical cleave (LSMC) show similar drops in pseudo fill factor pFF of -1.2
^%
_abs
, After PET, the TLS-separated cells regain 50
^%
_rel
of the pFF-drop, i.e. ApFF = +0.6
^%
_abs
, while the LSMC-separated ones regain 17
^%
_rel
in pFF after PET, i.e. ApFF = +0.2
^%
_abs
. Bifacial shingle solar cells processed with TLS and PET attain a peak designated area output power density of 23.5 mW/cm
²
that is 0.4 mW/cm
²
higher than a LSMC-separated shingle cell without PET (considering 100 W/ m2 irradiance from the rear side). The PET leads to improved cell results after separation into shingle cells. The edge passivation is most effective when applied on cells with TLS-separated and thus smooth edges.