What are the latest advancements in the development of perovskite-silicon tandem solar cells

The latest advancements in perovskite-silicon tandem solar cells reveal significant progress in efficiency, manufacturability, and practical deployment, bringing this promising technology closer to commercial reality and surpassing the limits of traditional silicon solar cells.

Efficiency Breakthroughs

• Record Efficiency Achievements:
  • Chinese manufacturer LONGi set a world record of 34.6% efficiency for a two-terminal (2T) perovskite-silicon tandem solar cell in June 2024 using a two-terminal device configuration.
  • Hanwha Qcells reached a 28.6% efficiency on a full-area M10-sized perovskite-silicon tandem solar cell, validated by the Fraunhofer Institute, marking a leap from lab-only to practical application.
  • Taiwan’s Academia Sinica demonstrated a 31.5% efficient 2T tandem cell, and Kyoto University spin-off EneCoat Technologies developed a four-terminal (4T) tandem cell with 30.4% efficiency using a proprietary low-temperature deposition process.
  • Swiss researchers at EPFL achieved 30.22% efficiency with a tandem cell featuring microtextured surfaces for enhanced performance.
  • Collaboration between China and Germany attained 25.7% efficiency in tandem cells combining perovskite with organic layers using a novel surface passivator.
• Architectural Innovations (2T vs 4T):
  The two main device architectures are 2T (series-connected) and 4T (two independent cells electrically isolated). While 2T tandems currently hold the highest efficiency records due to better light absorption, 4T offers greater flexibility for bandgap tuning and substrate choices, which enhances durability and manufacturing adaptability. 4T tandems can be fabricated on separate substrates from silicon, allowing better chemical, mechanical, and electrical isolation, potentially leading to more robust, long-lasting devices.

Manufacturing and Cost Reductions

• Perovskite layers can be deposited at much lower temperatures (below 150°C) compared to silicon cells (>1000°C), drastically reducing energy consumption and production costs by up to 90% in energy use.
• Solution-based processes with molecular-level precision have improved film uniformity and crystallinity, supporting scalability and cost-effective large-area production.
• Companies like Hanwha Qcells are already operating pilot tandem-cell production lines to transition from laboratory prototypes to mass manufacture. Automation and real-time quality control enhance throughput and device consistency.

Durability and Stability Enhancements

• Stability issues, historically a key challenge for perovskites, are being addressed through advanced hybrid architectures and encapsulation technologies, allowing devices to maintain peak performance over 1,000+ hours under real-world conditions.
• 4T tandem designs help improve stability by allowing independent optimization of perovskite and silicon cells, reducing strain and degradation caused by current mismatch in 2T devices.
• Use of intermediate 2D perovskite phases and novel passivators mitigates nonradiative recombination losses, improving open-circuit voltage and overall device stability.

Market and Application Outlook

• Perovskite-silicon tandem solar cells are extending the limits of silicon photovoltaics, which are nearing their theoretical efficiency ceiling (~29-30%). Tandems can potentially reach efficiencies above 40%, with some research projecting practical efficiencies up to about 39.5%.
• The tandem technology is applicable across scales—from residential rooftops to utility-scale solar farms—and is compatible with existing solar infrastructure, improving energy density and lowering system costs.
• Industry leaders like Oxford PV, Hanwha Qcells, and LONGi are advancing towards commercialization, with perovskite tandems expected to reshape solar manufacturing economics by enabling lower-cost, higher-performance modules.

Summary Table of Key Advances

In conclusion, perovskite-silicon tandem solar cells have transitioned from a largely theoretical concept to devices achieving record-breaking efficiencies with scalable manufacturing potential in 2025. Innovations in materials, device architectures (2T and 4T), and manufacturing processes are addressing previous challenges of efficiency limits, stability, and cost. This technology is poised to significantly advance solar energy deployment by surpassing silicon’s efficiency plateau and lowering the cost per watt of solar electricity generation.