Compensating Cutting Losses by Passivation Solution for Industry Upgradation of TOPCon and SHJ Solar Cells

Abstract

The main hurdle to the upgradation of photovoltaic industry is the large performance losses that the tunnel oxide passivated contact (TOPCon) and silicon heterojunction (SHJ) cells have during the cutting and separating process for the assembly of shingle solar panels. Here, an organic solution with the passivation effect is prepared in situ by a non‐vacuum spraying process, which effectively compensates the cutting loss caused by laser slicing technology. Both the open‐circuit voltage (Voc) and power conversion efficiency (PCE) are improved. For example, after edge passivation, the Voc and PCE of the 3 × 3 cm2 SHJ (K = 1.186%) cell increase by up to 8 mV and a 1–2% in absolute efficiency, respectively. This passivation‐solution based method can be easily integrated into the current production line and thus solve the issue of cutting loss in separated silicon solar cells. This study provides a new passivation technology to compensate the recombination loss on the edge surface caused by the cutting process in shingle solar panels.

The Development of Carbon/Silicon Heterojunction Solar Cells through Interface Passivation

“…Performing the advanced passivated edge technology on a 3 × 3 cm 2 SHJ cell with four un‐passivated edge surfaces, an initial efficiency of 22.7% increases to a higher 24.4%. [ 96 ] A shingle mini‐module by forming the cutting SHJ sub‐cells was prepared by Chen et al. and by passivating the newly formed edges with organic solution, the power of the mini‐module improved from 514.7 to 533.5 W.…”

“…These results demonstrate the role of water molecules in the passivation and de-passivation process. [162] Copyright 2022, John Wiley and Sons for Advanced Energy and Sustainability Research. b) DFT calculated charge density isosurfaces (0.05 e Bohr-3) for the passivation and de-passivation process.…”

“…The long-term stability of C/Si solar cells. a) Schematic diagram of the chemical reaction of the passivation and de-passivation mechanism [162]. Copyright 2022, John Wiley and Sons for Advanced Energy and Sustainability Research.…”

“…Copyright 2022, John Wiley and Sons for Advanced Energy and Sustainability Research. b) DFT calculated charge density isosurfaces (0.05 e Bohr-3) for the passivation and de-passivation process [162]. Copyright 2022, John Wiley and Sons for Advanced Energy and Sustainability Research.…”

Crystalline Si Surface Passivation with Nafion for Bulk Defects Detection with Electron Paramagnetic Resonance

“…In this latter application, passivation of laser-cut cell edges of the module fragment is needed prior to characterization with techniques such as electron paramagnetic resonance (EPR), 29 electrically detected magnetic resonance (EDMR), 30 deeplevel transient spectroscopy (DLTS), 31 and cell current− voltage (J−V) and Suns−V oc measurements. 32,33 In such cases, the defective, laser-damaged cell edges will obscure the true degradation mechanisms, and Nafion can effectively passivate them without causing further degradation of the bulk due to elevated-temperature passivation processes. Previously, Ji et al attributed the high quality of passivation of c-Si with Nafion to a high density of negative fixed charges (Q f ≈ 7 × 10 13 cm −2 ).…”