Flexibility - Page 7

A joint research team from the Gwangju Institute of Science and Technology (GIST) and the Korea Photonics Technology Institute has developed perovskite-enabled hybrid flexible copper indium gallium selenide (CIGS) thin-film solar cells that can convert all ultraviolet, visible and infrared sunlight into electric energy.

Current flexible CIGS thin-film solar cells are limited by a short wavelength band, from 300 to 390 nanometers, which is absorbed from the transparent electrodes at the top of the solar cell. They cannot convert short wavelength solar energy into electricity. The research team succeeded in developing CsPbBr₃ perovskite high-efficiency fluorescents that light up visible light bands by absorbing the light in the ultraviolet region, and applied them to the top of the transparent photoelectric layer of CIGS solar cells.

Researchers at the National University of Singapore (NUS) have developed highly efficient, large-area and flexible perovskite-based near-infrared LEDs for new wearable device technologies.

The team, led by Tan Zhi Kuang from the Department of Chemistry and the Solar Energy Research Institute of Singapore (SERIS), has developed high-efficiency near-infrared LEDs which can cover an area of 900 mm² using low-cost solution-processing methods. This is several orders of magnitude larger than the sizes achieved in previous reports, and opens up a range of new applications.

Researchers from the University of North Carolina have devised a method to rapidly produce large perovskite films for solar cells. The new approach, which combines the right amounts of volatile and less volatile solvents in a blade-coating process, could be an important step towards the commercialization of perovskite solar cells.

The blading process can create perovskite films rapidly to produce much larger devices than ever before. Image source: Yehao Deng et al/Science/AAAS

Although rapid deposition of large-area perovskite films under ambient conditions is an important goal in photovoltaics, rapid crystallization at low temperatures generally results in poor quality films that are not suitable for solar cell applications, so a slow growth and/or high temperatures are commonly used. The new method allows for the deposition of large-area, high-quality perovskite films at 99 mm/s under mild conditions. "We designed a general solvent mixing so that one can blade-coat continuous, large grain and compact perovskite films at unprecedented speed at room temperature in air" says team leader Jinsong Huang of the University of North Carolina.

Researchers at the Massachusetts Institute of Technology (MIT) have improved a transparent and conductive coating material by increasing its electrical conductivity by 10 times. When this coating material was integrated into a perovskite solar cell, it boosted the stability and efficiency of the solar cell.

'The goal is to find a material that is electrically conductive as well as transparent,' explained the team, which would be ‘'useful in a range of applications, including touch screens and solar cells.'

MIT researchers have designed perovskite photovoltaic-powered sensors that could potentially transmit data for years before they need to be replaced. To this end, the team mounted thin-film perovskite cells as energy-harvesters on inexpensive radio-frequency identification (RFID) tags.

The cells could power the sensors in both bright sunlight and dimmer indoor conditions. Moreover, the team found the solar power actually gives the sensors a major power boost that enables greater data-transmission distances and the ability to integrate multiple sensors onto a single RFID tag.

Solliance and U.S-based MiaSolé announced a new record - power conversion efficiency of 23% on a flexible tandem solar cell: a top flexible semi-transparent perovskite solar cell with a bottom flexible copper indium gallium selenide (CIGS) cell.

This achievement comes only 9 months after the January 2019 announcement by Solliance and MiaSolé regarding a flexible solar cell with an impressive power conversion efficiency of 21.5%. The solar cell, similarly to this newly announced one, combined two thin-film solar cell technologies into a 4 terminal tandem solar cell stack: a top flexible semi-transparent perovskite solar cell with a bottom flexible copper indium gallium selenide (CIGS) cell.

Saule Technologies announced that it finished construction of the first stage of its new cleanroom. The entire working area will be around 430 m², and should be complete in a couple of weeks.

Saule Technologies aims to launch a prototype production line by Q4 2019. The production line will include a modular system of printers with an annual production capacity of 40,000 sqm. In 2020, the company aims to increase the annual production capacity to 200,00 sqm.

Saule Technologies has announced that it has reached the point of technology development to be able to print its flexible, lightweight, semi-transparent, single junction solar modules with a consistent 10% efficiency. This performance, according to the Company, already enables BIPV and IoT applications in an economically viable manner.

By the end of March, Saule Technologies has also reached as high as 17.6% efficiency at the cell level (measured by an independent research institute). The durability has been significantly improved as well, with the latest stability tests indicating multiple years of flawless operation under accelerated ageing tests.

Researchers at the University of California, Irvine and other institutions have developed a new process for producing oxide perovskite crystals in flexible, free-standing layers.

'Through our successful fabrication of ultrathin perovskite oxides down to the monolayer limit, we've created a new class of two-dimensional materials,' said co-author Xiaoqing Pan, professor of materials science & engineering at UCI. 'Since these crystals have strongly correlated effects, we anticipate they will exhibit qualities similar to graphene that will be foundational to next-generation energy and information technologies.'

A joint research team including scientists from the Chinese Academy of Scinces (CAS), Shijiazhuang Tiedao University in China and Chiao Tung University in Taiwan has developed a novel type of highly flexible and stable perovskite-based solar cell that could be used in wearable electronics.

The team stated that current PSCs are mainly made of a polymer substrate, which has been proven fragile, unstable and not adequately waterproof. The team built a new type of PSC based on an inorganic mica substrate, which could reduce the strain in the device even under large bending deformation. Mica is a mineral that separates easily into small flat transparent pieces of rock.