High-Efficiency Flexible and Scalable Halide-Perovskite Solar Modules

To date, crystalline silicon-based solar cells dominate 90% of the solar market due to their technological maturity and high power conversion efficiency (PCE) of ~ 25%. However, these cells suffer from relatively high production costs, long energy payback times and are rigid, with heavy form factors. They are therefore unsuitable to power the rapidly growing portable electronics market, particularly wearables and Internet of Things (IoT) devices that are expected to reach trillions of units in the next few years. Current commercial solar technologies are also not compatible with the blooming mobile solar markets requiring high specific power (W/kg) or portable electronics requiring flexible form factors. It is therefore urgent to develop cheaper materials together with scalable manufacturing techniques to further accelerate the uptake of solar electricity. Here, metal halide perovskites have emerged as a new class of semiconductor having important applications in next generation solar cells. Indeed, an unprecedented advancement in the PCE of perovskite solar cells (PSCs) has resulted in the demonstration of devices having certified PCEs of 25.2% within just 8 years. Significantly, such materials are based on inexpensive starting compounds that can be processed at low-temperatures using solution-based techniques; properties that open up disruptive technology applications.

In this proposal we will develop fully flexible perovskite solar cells, with our aim being the development of devices that can power wearable technologies and IoT wireless devices. Scale-up of such technologies are also likely to find longer-term applications in utility and rooftop power generation and mobile solar (e.g. electric vehicles), and will be facilitated by a combination of ultra-low cost, high-volume manufacture processes together with selection of materials having reduced embodied energy. Here, the use of perovskite semiconductors is critical, as they can be deposited on temperature sensitive flexible plastic substrates using low-temperature processes.

We expect that success in our research will - in a shorter time frame - open the very large wearables and IoT power-source markets, and will power the increasing number of mobile (wireless) technologies that currently utilise conventional Li-ion power batteries. Indeed, there are already over 50 billion IoT devices in the market that currently map and gather information, and 127 new devices are connected to the internet each second, leading to a potential IoT market worth of US$1 trillion by 2023.

However the 10 trillion wireless sensors delivering the data needed by the IoT will need one million tons of lithium if they are to be powered by batteries; this represents the combined worldwide lithium production in 10 years. Besides the environmental impact of battery production, disposal and recycling, there are further costs that should be considered as batteries need regular maintenance.

Looking further ahead, we expect our project to de-risk the application of PSCs for larger scale deployment. Here, the exploitation of clean and renewable energy sources is a global challenge that we must solve in the next 30 years if we are to avoid non-reversible environmental changes. We therefore propose to exceed the state of the art in the development of current flexible perovskite solar cells (f-PSCs), where current single-junction perovskite devices demonstrate power conversion efficiencies of ~19% -- surpassing all competing flexible technologies. This will be developed together with key stability demonstrations.

Our project team represents some of the leading international experts in halide perovskite photovoltaics, including the leading industry partners in this space, giving a very high likelihood of success - allowing us to power a smart and flexible electronics future.