Printing-based methods like inkjet and roll-to-roll (R2R) printing offer scalable, potentially low-cost routes for manufacturing perovskite-silicon tandem solar cells, but optimizing these methods for large-scale production involves addressing several technical and process challenges. Based on recent advances and industry insights, here are key optimization strategies:
Optimization Strategies for Printing-Based Methods in Large-Scale Perovskite-Silicon Tandem Cell Production
1. Material Formulation and Ink Engineering
- Stable and printable perovskite inks: Development of perovskite precursor formulations that are stable in ambient conditions and compatible with printing techniques is critical. Additives such as dimethylammonium formate have been found to allow coating in ambient air and significantly extend cell lifetime by preventing rapid oxidation, mitigating the material degradation challenge inherent to perovskites.
- Tailored rheology for uniform deposition: Ink viscosity, surface tension, and drying behavior must be engineered to ensure uniform films with minimal defects over large areas, especially for roll-to-roll processes.
2. Process Control and Uniformity
- Precise layer thickness and morphology control: Printing methods must be optimized to produce highly uniform, pinhole-free perovskite layers with controlled crystallinity and grain size. This ensures high efficiency and reproducibility across large substrates (such as industry-standard M10 size wafers of ~189 cm²).
- Integration with silicon bottom cells: The perovskite top cell layer must be precisely aligned and optimized to stack over the silicon bottom cell, ensuring efficient light capture and electrical interfacing without damaging either layer.
3. Scalable, Ambient-Compatible Manufacturing
- Ambient air processing capabilities: Moving towards printing techniques that operate in ambient conditions rather than controlled inert gas environments reduces costs and complexity for large-scale production. Recent technology advances from industry leaders like Qcells demonstrate mass-production-feasible processes with perovskite layers processed in ambient air.
- High-throughput roll-to-roll setups: Roll-to-roll printing offers continuous manufacturing on flexible substrates, reducing cycle times and scaling production capacity. This requires robust inks and processing parameters that maintain cell performance during rapid coating and drying cycles.
4. Device Architecture and Design Optimization
- Two-terminal (2T) vs Four-terminal (4T) designs: Printing methods should accommodate the preferred tandem architecture. 4T designs, which allow better independence of each sub-cell, may be more compatible with printed layers since they exclude some constraints of back contact devices used in 2T architectures.
- Interface engineering: Optimizing electron and hole transport layers, along with interface passivation, through printable materials and processes is essential to enhance charge extraction and stability.
5. Durability and Stability Enhancements
- Encapsulation and protective coatings: Printing-compatible encapsulation layers or barrier coatings must be developed to protect perovskites from moisture, oxygen, and UV degradation after printing.
- Additives and compositional tuning: Incorporating additives into printable perovskite inks can improve tolerance to defects and extend operational lifetime under sunlight exposure, a key for commercial viability.
6. Cost and Equipment Considerations
- Use of standard industrial equipment: Processes should leverage existing industrial silicon wafer formats and scalable tools to enable integration into established photovoltaic manufacturing lines, minimizing new capital costs.
- Material cost reduction through scale: As perovskite precursor materials and printing equipment mature, cost reductions are expected, making printed tandem modules competitive with traditional silicon-only panels around or below $0.35/W.
Summary Table
| Optimization Aspect | Inkjet Printing | Roll-to-Roll Printing | Notes |
|---|---|---|---|
| Material Formulation | Stable, low-toxicity, printable inks | Stable inks with rheology for continuous coating | Additives for ambient air stability key |
| Process Control | High precision droplet placement | Uniform coating at high throughput | Crucial for morphology and thickness uniformity |
| Manufacturing Environment | Potential for small batch, flexible substrates | High-volume, continuous production | Ambient conditions preferred for cost reduction |
| Device Architecture | Compatible with multilayer structures | Can support flexible tandem cell designs | 4T designs favored for modularity |
| Durability | Needs encapsulation and passivation | Coatable barrier layers compatible | Degradation mitigation critical for commercial success |
| Cost and Scalability | Moderate throughput | Very high throughput and lower cost | Integration with standard industrial formats important |
Industry Examples & Progress
- Qcells has demonstrated a 28.6% efficient perovskite-silicon tandem cell using scalable processes suitable for industrial mass production, emphasizing use of processes that are compatible with mass manufacturing and standard wafer sizes.
- Oxford PV is commercializing perovskite-on-silicon tandem panels utilizing megawatt-scale pilot lines with the goal of gigawatt-scale production, highlighting the importance of scaling up printing and coating processes for commercial use.
- Techno-economic analyses by NREL support that printed tandem modules can reach competitive manufacturing costs while offering much higher efficiencies and energy yield per area.
Conclusion
Optimizing inkjet and roll-to-roll printing for large-scale production of perovskite-silicon tandem solar cells involves sophisticated material formulation to create stable printable inks, fine-tuned control of film uniformity and morphology, integration with silicon cell architectures, and scaling in ambient-compatible, high-throughput production lines. Advances from leading manufacturers demonstrate that these printing-based methods can be aligned with industrial standards, enabling cost-effective, efficient tandem solar module manufacturing with potential for broad commercial deployment in the near future.
Original article by NenPower, If reposted, please credit the source: https://nenpower.com/blog/how-can-printing-based-methods-like-inkjet-or-roll-to-roll-printing-be-optimized-for-large-scale-production-of-perovskite-silicon-tandem-solar-cells/
