Perovskite Solar - Page 71

Researchers from University of North Carolina, North Carolina State University and Chinese Academy of Sciences have fabricated a mini perovskite solar module using a novel encapsulation technique based on the use of a self-healable, lead-adsorbing ionogel that prevents lead leakage and improves stability. The solar module has an area of 31.5cm² and has a reported efficiency of 22.9%.

Ionogel microstructure and lead adsorption mechanism. Image from article

The scientists explained that ionogel sealants were applied on the panel's front glass and between electrode and encapsulation glass, with the 100μm-thick inonogel being able to hold the shattered glass together even if the glass breaks. This is claimed to effectively suppress lead leakage from broken modules after hail test or compression by car wheels, and soaking in water for 45 days.

Scientists in Germany's Karlsruhe Institute of Technology (KIT) have applied vapor-based deposition techniques and laser scribed interconnection (well established processes in existing thin-film solar manufacturing) to fabricate perovskite mini modules which achieved a maximum efficiency of 18% for a device measuring 4cm².

The team believes that based on these processes, it would be possible to simplify processing and reduce losses associated with scaling up to commercial-sized devices.

The U.S. Department of Energy has awarded The University of Toledo (UToledo) a one-year, $300,000 grant to advance research that could lead to the integration of promising perovskite solar cell technology into existing production lines for cadmium-selenide-telluride (CST)-based solar cells, maximizing the performance of thin-film tandem solar cells and reducing the costs of energy.

UToledo's work aims to collect light from both the front and back sides of the solar panel while interconnecting layers of perovskites and CST cells on both the front and the back faces of the solar panel. UToledo has a patent pending on the technology called monolithic bifacial perovskite-CST tandem cell.

A research team, led by Germany's Fraunhofer Institute for Solar Energy Systems (ISE), studied two stages of cell manufacturing that are among the most in need of optimization due to growing concerns over the availability of the commonly used indium and silver: transparent conductive oxide deposition and cell metallization.

The research takes processes used in silicon heterojunction (HJT) cell manufacturing as a starting point, and examines how the addition of a perovskite top cell would change the requirements for the rest of the cell structure.

Solliance recently announced that a collaboration with the M2N group of René Janssen at University of Technology Eindhoven has resulted in two world-records for 4T perovskite tandems.

The partners reported that they further optimized the wide-bandgap (1.69eV) perovskite cells with high near-infrared transparency for 4T tandem applications. The perovskite cell has reached a stabilized efficiency of 17.8% during 5-min maximum-power-point tracking. In combination with the Panasonic silicon bottom cell, a new world-record 4T perovskite/Si tandem efficiency of 29.2% was realized.

Scientists at the National Renewable Energy Laboratory (NREL) and Northern Illinois University (NIU) have developed a way to prevent lead from escaping damaged perovskite solar cells. This could go a long way in addressing concerns about potential lead toxicity.

Image by NREL, from Phys.org

The light-absorbing layer in perovskite solar cells contains a small amount of lead. Simply encapsulating solar cells does not stop lead from leaking if the device is damaged. Instead, chemical absorption may hold the key. The researchers report being able to capture more than 99.9% of the leakage.

A research team at KTH Royal Institute of Technology has developed a synthetic alloy that increases perovskite cells' durability while preserving energy conversion performance.

'Perovskite usually dissolves immediately on contact with water,' says co-author James Gardner, a researcher at KTH. 'We have proven that our alloyed perovskite can survive for several minutes completely immersed in water, which is over a 100 times more stable than the perovskite alone. What's more, the solar cells that we have built from the material retain their efficiency for more than 100 days after they are manufactured.'

A research team from the Fraunhofer Institute for Solar Energy Systems, NREL, Solaronix SA and the Materials Research Center of the University of Freiburg has reported perovskite solar cells with carbon-based electrodes, which demonstrate impressive resilience against reverse-bias-induced degradation.

Previous studies have shown that a negative voltage applied to conventional perovskite solar cell stacks resulted in breakdown and irreversible destruction of the device. In this study, the international research team identified two main degradation mechanisms. The first is iodine loss due to hole tunneling into perovskite, which takes place even at low reverse-bias but decomposes the perovskite only after long time durations. Another factor is local heating at large reverse-bias leading to the formation of PbI₂, which starts at shunts and then follows the path of the least resistance for the cell current, which is primarily influenced by the electrode sheet resistance. The newly designed modules successfully endured the hotspot test conditions specified in IEC 61215-2:2016 international standard at an accredited module testing laboratory.

Researchers at South Korea's Ulsan National Institute of Science and Technology (UNIST) and Pohang University of Science and Technology report a power conversion efficiency of 25.8% for a single junction perovskite solar cell, by forming a coherent interlayer between electron-transporting and perovskite layers to reduce interfacial defects.

The cell was built with an interlayer between a tin(IV) oxide (SnO₂) electron-transporting layer and a layer made of a halide perovskite layer by coupling chlorine-bonded SnO₂ with a perovskite precursor containing chlorine. 'This interlayer has atomically coherent features which enhance charge extraction and transport from the perovskite layer; and fewer interfacial defects,' the academics explained.

Saule Technologies, developer and manufacturer of perovskite solar cells, recently announced that it is 'making good progress towards getting listed on the NewConnect Alternative Trading System'.

Saule and its shareholders, including the majority holder, Columbus Elite Global S.A. (formerly Blumerang Investors S.A.), have signed an investment agreement, setting the rules for Columbus Elite Global (CEG) to acquire Saule's shares. With this transaction, Saule will become part of the CEG capital group, which is listed on NewConnect. In return for transferring their shares to Columbus Elite Global, Saule's shareholders will get shares in the higher share capital of CEG.