Using toxic materials to create clean energy? A win-win situation never sounded so good. MIT professor Angela Belcher has created a process for using the lead from old car batteries to create solar cells. This innovation fantastic for the environment on multiple levels - dead batteries will be kept from stacking up in landfills while clean, renewable energy is simultaneously created. Recycling at its finest. Here is an excerpt:
Laboratory experiments confirm that solar cells made with recycled lead work just as well as those made with high-purity, commercially available starting materials. Battery recycling could thus support production of these novel solar cells while researchers work to replace the lead with a more benign but equally effective material.
Much attention in the solar community is now focused on an emerging class of crystalline photovoltaic materials called perovskites. The reasons are clear: The starting ingredients are abundant and easily processed at low temperatures, and the fabricated solar cells can be thin, lightweight, and flexible — ideal for applying to windows, building facades, and more. And they promise to be highly efficient.
Unlike most advanced solar technologies, perovskites are rapidly fulfilling that promise. “When perovskite-based solar cells first came out, they were a few percent efficient,” says Angela Belcher, the James Mason Crafts Professor in biological engineering and materials science and engineering at MIT. “Then they were 6 percent efficient, then 15 percent, and then 20 percent. It was really fun to watch the efficiencies skyrocket over the course of a couple years.” Perovskite solar cells demonstrated in research labs may soon be as efficient as today’s commercial silicon-based solar cells, which have achieved current efficiencies only after many decades of intensive research and development.
Research groups are now working to scale up their laboratory prototypes and to make them less susceptible to degradation when exposed to moisture. But one concern persists: The most efficient perovskite solar cells all contain lead.