Perovskite solar excels from its high conversion efficiency, relatively simple manufacturing process, and eco-friendliness, though issues such as instability and accelerated manufacturing speed must be resolved before realizing exrensive commercialization and popularization, in order to avoid the “death valley”. Stanford University had expedited on the development of perovskite batteries accordingly, and managed to develop an exclusive “high speed manufacturing equipment” that is able to produce a 12m perovskite film within a minute.
Nick Rolston, postdoctoral of Stanford University, commented that perovskite solar is currently standing at the intersection of commercialization and failure, and the future of the particular technology may be terminated if scientists are unable to transcend from the predicament of battery stability within the next 3 years, despite the several million of funds that went into the investment of the technology from the past.
Perovskite solar cells are made of crystals formed with cheap and abundant iodine, carbon, and lead, and are able to grow under the water near boiling temperature, with less energy required compared to the traditional polysilicon solar cells that need 3000 °C of refinement. Perovskite is lightweight, which can be produced into flexible modules, and let’s not forget about the diversified designs of the solar panels, as well as the 25% conversion efficiency.
Unfortunately, it will take quite a significant period of time before this particular technology sees the light of day. The existing perovskite solar cell that has a higher conversion efficiency is about the size of a nail, and will derive defects and pinholes once the dimension is expanded, with substantial deterioration in efficiency.
The research team plans to produce a new small-scale demonstration equipment in the laboratory by constructing a perovskite solar film using two nozzles through the patented rapid spraying plasma technology, where chemical solution is first applied on the underlying glass, before releasing the highly responsive ionized gas or plasma from another nozzle. Rolston commented that a traditional process requires a 30-minute baking procedure of the perovskite solution, and the plasma technology is able to accelerate the speed of transformation from liquid perovskite to a thin film.
As pointed out by the research, the new rapid spraying process produces a 12m perovskite thin film in one minute, which is 4 times the speed of polysilicon solar cells. In addition, the relatively cheaper manufacturing cost at US$0.25 per square foot is also far cheaper than polysilicon solar cells at US$2.5. The perovskite solar cell achieves a conversion efficiency of 18%, and will drop to 15.5% after 5 months of placement.
Rolston commented that the team wishes an extensive use of this particular technology, and the public is able to purchase the plasma processing system with a reasonable price from the market, despite its seemingly professional title.
Polysilicon solar has been lowered to US$0.05/KWh in cost, and is the most common photovoltaic technology in the market, though a number of potential technology is glowing in the dark with the rapidly progressing technology. Rolston believes that a perovskite solar module that stays intact for 30 years will be able to lower the cost of electricity to below US$0.02/KWh, and for that a better moisture-proof packaging technology is the next step in development for the team.
(Cover photo source: 史丹佛大學)