Abstract The bifacial p-type silicon (p-Si) passivated emitter and rear cells (PERCs) are predicted to dominate the industrial bifacial solar cells. In this work, we have investigated the impact of different rear surface morphologies on the electrical performance of bifacial PERCs with both five-busbar (5BB) and nine-busbar (9BB) grid design. The passivation and optical properties with differing rear surfaces are evaluated on semi-device structures. The depth of local aluminum back surface field is hardly affected by the rear surface morphology. The calculated efficiency loss analysis indicates that the negative electrical impact with enlarged rear surface area is more serious for rear side than that of front side. The batch conversion efficiency of 9BB bifacial PERCs increases by 0.2%–0.3% comparing to 5BB ones depending on the rear surface roughness. Consequently, a highest front-side average efficiency of 22.57%, with a champion efficiency of 22.75%, has been achieved for 9BB bifacial p-Si PERCs with a nearly planar rear surface. A highest bifaciality of 78.7% is realized for both 5BB and 9BB bifacial PERCs with the roughest rear surface. We have further simulated the relative enhancement of electric generation to compare the performance of bifacial PERCs in practical application.

中文翻译：

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工业双面PERC太阳能电池背面粗糙度和金属网格设计的优化

摘要 双面 p 型硅 (p-Si) 钝化发射极和背面电池 (PERC) 预计将主导工业双面太阳能电池。在这项工作中，我们研究了不同背面形态对具有五母线 (5BB) 和九母线 (9BB) 网格设计的双面 PERC 电气性能的影响。在半器件结构上评估具有不同背面的钝化和光学特性。局部铝背面场的深度几乎不受背面形态的影响。计算的效率损失分析表明，背面面积扩大后的负电影响比正面更严重。9BB 双面PERCs 的批量转换效率提高了0.2%–0。3% 与 5BB 相比，取决于后表面粗糙度。因此，具有近乎平面后表面的 9BB 双面 p-Si PERC 实现了 22.57% 的最高正面平均效率和 22.75% 的最佳效率。背面最粗糙的 5BB 和 9BB 双面 PERC 均实现了 78.7% 的最高双面性。我们进一步模拟了发电量的相对增强，以比较双面 PERC 在实际应用中的性能。