Perovskite solar cells have been the focus recently in the solar research. In less than 2 years, perovskite solar cells efficiency has been improved to more than 19%, which is close to most of the commercial available solar cells.
Researchers from MIT, U.S.A., have found a way to produce a 0.5um (0.0000005 meter) thick thin-film Pb-based perovskite solar cells using recycled lead from old car batteries. This helps to divert toxic material from landfills the old batteries and reuse it in solar panels that could go on producing power for decades. Each single car battery can produce enough solar panels to power 30 households.
The technology behinds isn't new. The team extracted the lead (Pb) and lead-dioxide (PbO2) from the battery's positive and negative electrodes, respectively, and ground to fine pieces. Then they heated up the PbO2 to 600 degree Celsius to convert to PbO (lead-oxide). The Pb was dissolved into Nitric acid and PbO was dissolved into acetic acid. Potassium-iodide was then added to both solutions to form lead-iodide which then will be sprayed deposited onto the transparent substrate, following with sequential deposit, to form solar cell.
For more info and video to produce the solar cells go to http://newsoffice.mit.edu/2014/recycling-batteries-into-solar-cells-0818.