Spectroscopic Dynamic Digital-Twin Model Reveals Practical Optimization Strategy of SHJ Solar Cells

Area of Science:

• Photovoltaics and Renewable Energy
• Materials Science and Engineering
• Semiconductor Device Physics

Background:

• Silicon heterojunction (SHJ) solar cells are gaining investment due to bifacial performance, durability, and tandem compatibility.
• Optimizing SHJ solar cells requires high-fidelity device modeling that considers both power conversion efficiency (PCE) and marginal PCE gains.
• Conventional device modeling, often validated only by DC testing, is insufficient for capturing complex carrier dynamics.

Purpose of the Study:

• To establish a digital twin model for SHJ solar cells.
• To validate the model using both current-voltage (JV) and time-resolved photovoltage (TPV) spectroscopy.
• To correlate device performance with spatiotemporal carrier dynamics and identify practical optimization strategies.

Main Methods:

• Development of a digital twin model for SHJ solar cells.
• Validation of the model using both JV characteristics and spectroscopic TPV measurements.
• Quantitative analysis of inaccessible parameters like defect energy, density, and capture cross-sections.

Main Results:

• The digital twin model successfully reproduces both steady-state and transient device behavior.
• The model enables quantitative estimation of critical carrier dynamics parameters.
• Marginal revenue analysis identified practical optimization windows for SHJ solar cell development.

Conclusions:

• The digital twin model bridges the gap between idealized simulations and industrial reality for SHJ solar cells.
• Further reductions in charge transport layer defects and silicon doping offer diminishing returns.
• This modeling platform accelerates the development of next-generation photovoltaic technologies.