Bifacial p-Type Silicon Shingle Solar Cells - the "pSPEER" Concept

Shingled interconnection of solar cells allows increased output power density p(out) by (i) increasing the active cell area within the module, (ii) decreasing shading losses, and (iii) reducing both series resistance per cell as well as interconnection losses. An additional increase in p(out) is possible by shingled interconnection using bifacial solar cells, allowing the light capture from the rear side as well. The p-type silicon shingled passivated edge, emitter, and rear (pSPEER) solar cell concept introduced and examined in this work as an approach for fabrication of bifacial shingle solar cells is based on the passivated emitter and rear cell (PERC) concept. This article portrays bifacial pSPEER solar cells that are fabricated using industrial 6-inch p-type Czochralski-grown silicon PERC precursors. After contact firing, the 6-inch host wafers are separated by means of conventional laser scribing and manual mechanical cleaving into six pSPEER solar cells each with an area of 23 x 148 mm(2). Current-voltage measurements of these bifacial pSPEER solar cells with front side illumination yield peak p(out,f) = 20.4 mW cm(-2) on a black background (total cell area, busbar included). For an irradiance of 1000 W m(-2), this p(out,f) is equivalent to an energy conversion efficiency of 20.4%. By additional rear side illumination with an irradiance of 100 W m(-2), peak p(out) = 21.5 mW cm(-2) is obtained for these pSPEER solar cells.