Dead auto batteries may be able to keep on truckin’ as long-lasting solar panels. Researchers at MIT are developing a system based on organolead halide perovskite, a technology that uses lead from raw ores in solar cell manufacturing. By using recycled lead from discarded car batteries, this toxic material can be diverted and reused in photovoltaics. The production of perovskite solar cells is a relatively simple and benign process. “It has the advantage of being a low-temperature process, and the number of steps is reduced” compared with the manufacture of conventional solar cells, said MIT professor Dr. Angela M. Belcher. The organolead halide perovskite was found to take the form of a thin film half a micron thick. As a result, the lead from a single car battery could produce enough solar panels to provide power for 30 households, according to the researchers. Perovskite-based cells have already achieved power conversion efficiency of more than 19 percent, which is close to that of many commercial silicon-based solar cells. The new recycled-material-based cells have also already proven less expensive to manufacture. In a finished perovskite-based solar panel, the lead-containing layer would be fully encapsulated by other materials. This limits the risk of lead contamination in the environment. When the panels are eventually taken out of service, the lead can again be recycled into new solar panels. Furthermore, lead recovered from old batteries is just as effective in the production of perovskite solar cells as freshly produced metal, the researchers said. Today, 90 percent of the lead recovered from recycling old batteries is used to produce new batteries. But lead-based car batteries are quickly being replaced by new, more efficient types, such as lithium-ion batteries. “Once the battery technology evolves, over 200 million lead-acid batteries will potentially be retired in the United States, and that could cause a lot of environmental issues,” Belcher said. The work was funded by Italian energy company Eni through the MIT Energy Initiative. The research was published in Energy and Environmental Science (doi: 10.1039/C4EE00965G). For more information, visit www.mit.edu.