Perovskite Modules Research Articles

Economically Sustainable Growth of Perovskite Photovoltaics Manufacturing

Summary The significant capital expense of photovoltaics manufacturing has made it difficult for new cell and module technologies to enter the market. We present two technoeconomic models that analyze the sustainable growth of perovskite manufacturing for an R2R single-junction technology and a perovskite-silicon tandem module, focusing on the impacts of economies of scale and average selling price on profitability. We establish a cost range of $3.30/W to $0.53/W for flexible modules manufactured in factory sizes ranging from 0.3 MW/year to 1 GW/year. In addition, we model the cost to manufacture a tandem module consisting of a single-junction perovskite cell stacked in 4-terminal configuration onto a silicon cell and show how an existing manufacturer can grow at a faster rate by co-investing in tandems. Our analyses highlight potential routes to market for perovskite photovoltaics and the possibility to sustainably grow a photovoltaics manufacturing company even in markets with higher labor rates.

Direct observation of continuous networks of ‘sol–gel’ processed metal oxide thin film for organic and perovskite photovoltaic modules with long-term stability

Continuous metal oxygen networks of TiOx are formed on top of organic semiconductors with favorable surface energy, which prolong T80-lifetime for organic and perovskite modules up to more than 2000 hours.

Scalable Fabrication of Efficient Perovskite Solar Modules on Flexible Glass Substrates

AbstractPerovskite materials are good candidates for flexible photovoltaic applications due to their strong absorption and low‐temperature processing, but efficient flexible perovskite modules have not yet been realized. Here, a record efficiency flexible perovskite solar module is demonstrated by blade coating high‐quality perovskite films on flexible Corning Willow Glass using additive engineering. Ammonium chloride (NH4Cl) is added into the perovskite precursor solution to retard the nucleation which prevents voids formation at the interface of perovskite and glass. The addition of NH4Cl also suppresses the formation of PbI2 and reduces the trap density in the perovskite films. The implementation of NH4Cl enables the fabrication of single junction flexible perovskite solar devices with an efficiency of 19.72% on small‐area cells and a record aperture efficiency of 15.86% on modules with an area of 42.9 cm2. This work provides a simple way to scale up high‐efficiency flexible perovskite modules for various applications.

Block Iodide, Save Perovskite Modules

Stability of small area perovskite solar cells has been notably improved, but large area modules have not been proven stable. Recently in Joule, E. Bi and coworkers present a highly stable perovskite module that kept 90% of its initial efficiency after 1,000 h operation under illumination. The secret is an iodide diffusion blocking layer (DBL) added at the module interconnection. The DBL with 2D graphitic carbon nitride (g-C3N4) flakes can suppress iodide diffusion at the interconnection and prevent electrode corrosion.

Energy yield analysis of textured perovskite silicon tandem solar cells and modules.

Perovskite silicon tandem solar cells combine potentially low production costs with the ability to surpass the efficiency limit of silicon single junction solar cells. Optical modeling and optimization are crucial to achieve this ambitious goal in the near future. The optimization should seek to maximize the energy yield based on realistic environmental conditions. This work analyzes the energy yield of perovskite silicon tandem solar cells and modules based on realistic experimental data, with a special focus on the investigation of surface textures at the front and rear side of the solar cell and its implication for reflection as well as parasitic absorption properties. The investigation reveals a 7.3%rel higher energy yield for an encapsulated tandem cell with a textured front side compared with an encapsulated high efficiency single junction solar cell with 24.3% harvesting efficiency for irradiance data of the year 2014 in Freiburg/Germany.

(Invited) Scalable Roll-to-Roll and Sheet-to-Sheet Processing for Perovskite Photovoltaics

Metal halide perovskites have emerged as a highly promising solar cell technology with high light to electric power conversion efficiency and low processing cost due to their solution processability. However, to make perovskite solar cells commercially viable, particularly to compete with or build upon the traditional silicon dominated photovoltaic market, substantial progress is needed in improving their process techniques and scalability. Fabricating perovskite devices and modules in a roll-to-roll process on flexible substrates will enable high throughput manufacturing, and it will also allow the application space to be extended beyond what is available to rigid geometries. We developed chemistries, contact and absorber layers, that can be deposited in a roll-to-roll fashion using scalable slot-die coating. Progress of scaling up perovskites to larger area, sheet-to-sheet and roll-to-roll, on flexible substrates will be reported. Insight will be given in module performance and the stability of such modules.

Reduction of lead leakage from damaged lead halide perovskite solar modules using self-healing polymer-based encapsulation

In recent years, the major factors that determine commercialization of perovskite photovoltaic technology have been shifting from solar cell performance to stability, reproducibility, device upscaling and the prevention of lead (Pb) leakage from the module over the device service life. Here we simulate a realistic scenario in which perovskite modules with different encapsulation methods are mechanically damaged by a hail impact (modified FM 44787 standard) and quantitatively measure the Pb leakage rates under a variety of weather conditions. We demonstrate that the encapsulation method based on an epoxy resin reduces the Pb leakage rate by a factor of 375 compared with the encapsulation method based on a glass cover with an ultraviolet-cured resin at the module edges. The greater Pb leakage reduction of the epoxy resin encapsulation is associated with its optimal self-healing characteristics under the operating conditions and with its increased mechanical strength. These findings strongly suggest that perovskite photovoltaic products can be deployed with minimal Pb leakage if appropriate encapsulation is employed.

Facile and scalable fabrication of low-hysteresis perovskite solar cells and modules using a three-step process for the perovskite layer

A new coating and forming process is reported for perovskite solar cells and modules. Power conversion efficiencies (PCEs) of 15.0% in the active area and 14.0% in the aperture area are achieved in a module consisting of four sub-cells connected in series with an aperture area of 5 cm × 5 cm. The I–V characteristics of the cells and modules show low hysteresis. This new process consists of three steps: coating, gas blowing, and dipping into an antisolvent. The process exhibits high reproducibility of PCE in 1 cm2 cells, and forms the perovskite layer over a large area. The size effect of the active area on the PCE is little in the cell (active area: 0.5 cm2) and module (active area: 25 cm2). This approach paves the way for the industrial production of large-scale perovskite modules.

Series and Parallel Module Design for Large-Area Perovskite Solar Cells

Organometal halide perovskites have exhibited a bright future as photovoltaic semiconductor in next-generation solar cells because of their unique and promising physicochemical properties. However, large-area perovskite solar cells (PSCs) have suffered from problems of low efficiency with large active area and output module designing. Herein, we research the influence of the length and width on output performance when device areas are increased and design of series and parallel connection for large-area PSC modules. The results show that high efficiencies of 19.52 and 18.65% are obtained for single solar cell of areas of 0.1 and 1.0 cm2, respectively. When the device area is increased, increasing the length of the device can achieve a higher efficiency than increasing the width for single PSCs. By comparing series and parallel connection mode, we found that first series and then parallel perovskite module is the best way to obtain a high power output. The design research for perovskite modules offers direction for PSC modules in future applications.

Rapid Aqueous Spray Fabrication of Robust NiOx: A Simple and Scalable Platform for Efficient Perovskite Solar Cells

AbstractOrganometal halide perovskites have powerful intrinsic potential to drive next‐generation solar technology, but their insufficient thermomechanical reliability and unproven large‐area manufacturability limit competition with incumbent silicon photovoltaics. This work addresses these limitations by leveraging large‐area processing and robust inorganic hole transport layers (HTLs). Inverted perovskite solar cells utilizing NiOx HTLs deposited by rapid aqueous spray‐coating that outperform spin‐coated NiOx and lead to a 5× improvement in the fracture energy (Gc), a primary metric of thermomechanical stability, are presented. The morphology, chemical composition, and optoelectronic properties of the NiOx films are characterized to understand and optimize compatibility with an archetypal double cation perovskite, Cs.17FA.83Pb(Br.17I.83)3. Perovskite solar cells with sprayed NiOx show higher photovoltaic performance, exhibiting up to 82% fill factor and 17.7% power conversion efficiency (PCE)—the highest PCE reported for inverted cell with scalable charge transport layers—as well as excellent stability under full illumination and after 4000 h aging in inert conditions at room temperature. By utilizing open‐air techniques and aqueous precursors, this combination of robust materials and low‐cost processing provides a platform for scaling perovskite modules with long‐term reliability.

Mitigating scalability issues of perovskite photovoltaic technology through a p-i-n meso-superstructured solar cell architecture

The relevance of perovskite photovoltaics is fully supported by its impressive development in recent years. Besides high efficiency, adoption of this technology requires obtaining long operational stability and cost-effective fabrication methods of large area devices. With the current perovskite solar cell (PSC) configurations (planar or meso n-i-p), it is difficult to deposit uniform pin-hole free films over large area at low temperature (<100 °C). In order to solve the above issues, we adopt a fabrication strategy for the scaling up of perovskite solar cells. Particularly, we study and fabricate a meso-superstructured p-type/intrinsic/n-type (p-i-n) cell (p-i-n-meso) configuration in which the insulating mesoporous layer of Al2O3 plays a key role in the fabrication of perovskite solar modules and therefore we also draw attention to this structure that has been out of the map for the fabrication of large area perovskite devices. The potential of this architecture is demonstrated through fabrication of devices ranging from small area (9 mm2) up to eight-cell CH3NH3PbI3 perovskite modules over substrates as large as 100 cm2. A record photovoltaic conversion efficiency (PCE) of 9.3% and geometrical fill factor (GFF) of 84% was reached for a module with 17 cm2 of active area. Additionally, we carried out an in-situ monitoring of the photovoltaic parameters of one perovskite module for 2000 h under outdoor conditions, giving evidence of the high performance and stability of encapsulated perovskite photovoltaic technology in a real operational environment. This study paves the way to the upscaling of stable, efficient and full-solution-processed PSCs.

Cu-doped nickel oxide interface layer with nanoscale thickness for efficient and highly stable printable carbon-based perovskite solar cell

The power conversion efficiency (PCE) of hole conductor free carbon-based perovskite solar cells (PSCs) is restricted by the poor charge extraction and recombination losses at the carbon-perovskite interface. For the first time we successfully demonstrated incorporation of thin layer of copper doped nickel oxide (Cu:NiOx) nanoparticles in carbon-based PSCs, which helps in improving the performance of these solar devices. Cu:NiOx nanoparticles have been synthesized by a facile chemical method, and processed into a paste for screen printing. Extensive X-ray Absorption Spectroscopy (XAS) analysis elucidates the co-ordination of Cu in a NiOx matrix and indicates the presence of around 5.4% Cu in the sample. We fabricated a monolithic perovskite module on a 100 cm2 glass substrate (active area of 70 cm2) with a thin Cu:NiOx layer (80 nm), where the champion device shows an appreciated power conversion efficiency of 12.1% under an AM 1.5G illumination. To the best of our knowledge, this is the highest reported efficiency for such a large area perovskite solar device. I-V scans show that the introduction of Cu:NiOx mesoporous scaffold increases the photocurrent, and yields fill factor (FF) values exceeding 57% due to the better interface and increased hole extraction efficiency. Electrochemical Impedance Spectroscopy (EIS) results reinforce the above results by showing the reduction in recombination resistance (Rrec) of the PSCs that incorporates Cu:NiOx interlayer. The perovskite solar modules with a Cu:NiOx layer are stable for more than 4500 h in an ambient environment (25 °C and 65% RH), with PCE degradation of less than 5% of the initial value.

Br-containing alkyl ammonium salt-enabled scalable fabrication of high-quality perovskite films for efficient and stable perovskite modules

The incorporation of a Br-containing tetrabutylammonium salt into perovskite precursors demonstrates superior advantages in both crystallization and large-area uniformity control during the scalable blade-coating of perovskite films.

Outdoor performance of perovskite solar technology: Silicon comparison and competitive advantages at different irradiances

Perovskite solar cells have shown an impressive performance evolution during the last years. This technology has been mostly tested under laboratory conditions using small area devices. In this work, the outdoor photovoltaic performance of perovskite solar cells was evaluated under real tropical weather conditions. Specifically, two perovskite modules with active area of 17 and 50 cm2 were fabricated, encapsulated and tested. Taking a commercial silicon panel as reference, both technologies were evaluated for 500 h correlating the in-situ I-V measurements with atmospheric variables measured every minute during the light hours. To obtain the performance and the average outdoor efficiency of devices, we proposed a new adapted methodology based on the standard IEC 61853-1, showing the photovoltaic parameters performance through maps, to graphically visualize their behavior in a broad range of atmospheric conditions. Additionally, we demonstrated that the power delivery and short circuit current of both technologies correlate linearly with the atmospheric variables. Moreover, the open circuit voltage of perovskite technology exhibited a nonlinear behavior and an improved performance with temperature at high irradiance regimes. This work presents reliable information concerning perovskite solar technology performance under real outdoor operation conditions, being this crucial to identify competitive advantages of this technology and the aspects to be improved.

Perovskite Photovoltaic Modules: Life Cycle Assessment of Pre-industrial Production Process

SummaryPhotovoltaic devices based on perovskite materials have a great potential to become an exceptional source of energy while preserving the environment. However, to enter the global market, they require further development to achieve the necessary performance requirements. The environmental performance of a pre-industrial process of production of a large-area carbon stack perovskite module is analyzed in this work through life cycle assessment (LCA). From the pre-industrial process an ideal process is simulated to establish a benchmark for pre-industrial and laboratory-scale processes. Perovskite is shown to be the most harmful layer of the carbon stack module because of the energy consumed in the preparation and annealing of the precursor solution, and not because of its Pb content. This work stresses the necessity of decreasing energy consumption during module preparation as the most effective way to reduce environmental impacts of perovskite solar cells.

Electrode Design to Overcome Substrate Transparency Limitations for Highly Efficient 1 cm2 Mesoscopic Perovskite Solar Cells

Summary Fluorine-doped tin oxide glass substrate is typically used for state-of-the-art perovskite solar cells (PSCs). However, indium-doped tin oxide (ITO) is better due to higher transparency for a given conductivity, although it has lower tolerance to high-temperature processes required for the compact and mesoporous TiO2 layers. Here we overcome this challenge by developing and utilizing a new electrode design. We successfully demonstrate high-efficiency mesoscopic PSCs on annealed ITO substrates showing improved photocurrent without sacrificing fill factor. After further optimizations of cell geometry and substrate conductivity guided by simulation, a certified 19.63% efficiency is achieved on 1 cm2 for ITO-based mesoscopic PSC, which is the highest among PSCs prepared by gas quenching. This work is useful for providing design principles and methods for optimizing cell geometry, metal electrode design, and substrate conductivity requirements for large-area PSCs.

Outdoor Measurement and Modeling of Perovskite Module Temperatures.

Photovoltaic cells and modules are exposed to partially rapid changing environmental parameters that influence the device temperature. The evolution of the device temperature of a perovskite module of 225 cm2 area is presented during a period of 25 days under central European conditions. The temperature of the glass–glass packaged perovskite solar module is directly measured at the back contact by a thermocouple. The device is exposed to ambient temperatures from 3 to 34 °C up to solar irradiation levels exceeding 1300 W m−2. The highest recorded module temperature is 61 °C under constant high irradiation levels. Under strong fluctuations of the global solar irradiance, temperature gradients of more than 3 K min−1 with total changes of more than 20 K are measured. Based on the experimental data, a dynamic iterative model is developed for the module temperature evolution in dependence on ambient temperature and solar irradiation. Furthermore, specific thermal device properties that enable an extrapolation of the module response beyond the measured parameter space can be determined. With this set of parameters, it can be predicted that the temperature of the perovskite layer in thin‐film photovoltaic devices is exceeding 70 °C under realistic outdoor conditions. Additionally, perovskite module temperatures can be calculated in final applications.

Cost Analysis of Perovskite Tandem Photovoltaics

Summary Recently, metal halide perovskite photovoltaics (PV) are marching toward commercialization. The possibility for perovskite absorbers to be incorporated into multi-junction solar cells is also being discussed, which suggests alternative market entry. Although intensive investigations are being made on their technical feasibility, serious analysis on the cost of perovskite-based tandem modules is lacking. The levelized cost of electricity (LCOE) of solar modules is often used to evaluate technoeconomic competitiveness. Here, we performed a detailed cost analysis on two perovskite-based tandem modules (the perovskite/c-silicon and the perovskite/perovskite tandem module) compared with standard multi-crystalline silicon and single-junction perovskite solar cells. We found that perovskite PVs (both single junction and multi-junction) are competitive in the context of LCOE if the module lifetime is comparable with that of c-silicon solar cells. This encourages further efforts to push perovskite tandem modules onto the market in the future.

Efficient fully laser-patterned flexible perovskite modules and solar cells based on low-temperature solution-processed SnO2/mesoporous-TiO2 electron transport layers

Efficient flexible perovskite solar cells and modules were developed using a combination of SnO2 and mesoporous-TiO2 as a fully solution-processed electron transport layer (ETL). Cells using such ETLs delivered a maximum power conversion efficiency (PCE) of 14.8%, which was 30% higher than the PCE of cells with only SnO2 as the ETL. The presence of a mesoporous TiO2 scaffold layer over SnO2 led to higher rectification ratios, lower series resistances, and higher shunt resistances. The cells were also evaluated under 200 and 400 lx artificial indoor illumination and found to deliver maximum power densities of 9.77 μW/cm2 (estimated PCE of 12.8%) and 19.2 μW/cm2 (estimated PCE of 13.3%), respectively, representing the highest values among flexible photovoltaic technologies reported so far. Furthermore, for the first time, a fully laser-patterned flexible perovskite module was fabricated using a complete three-step laser scribing procedure (P1, P2, P3) with a PCE of 8.8% over an active area of 12 cm2 under an illumination of 1 sun.

Scalable fabrication of perovskite solar cells

Perovskite materials use earth-abundant elements, have low formation energies for deposition and are compatible with roll-to-roll and other high-volume manufacturing techniques. These features make perovskite solar cells (PSCs) suitable for terawatt-scale energy production with low production costs and low capital expenditure. Demonstrations of performance comparable to that of other thin-film photovoltaics (PVs) and improvements in laboratory-scale cell stability have recently made scale up of this PV technology an intense area of research focus. Here, we review recent progress and challenges in scaling up PSCs and related efforts to enable the terawatt-scale manufacturing and deployment of this PV technology. We discuss common device and module architectures, scalable deposition methods and progress in the scalable deposition of perovskite and charge-transport layers. We also provide an overview of device and module stability, module-level characterization techniques and techno-economic analyses of perovskite PV modules. Perovskite solar cells (PSCs) have emerged as a revolutionary class of photovoltaic technology. Here, we review recent progress and challenges in scaling up PSCs towards commercialization. We discuss several areas, including device architectures, deposition methods, scalable deposition of perovskite and charge transport layers, device stability, module-level characterization and techno-economic analyses.