That means that after your old car battery dies, it may one day find new life, creating enough clean, renewable energy to power 30 households while also helping to reduce lead pollution. Exposure to lead has been shown to cause cognitive and behavioral problems in children.
Professors and graduate students at the university published their findings in the journal Energy and Environmental Science. They described how recent advances in solar technology allow for the use of a lead-based substance called perovskite to make solar cells.
“Amazingly, because the perovskite photovoltaic material takes the form of a thin film just half a micrometer thick, the team’s analysis shows that the lead from a single car battery could produce enough solar panels to provide power for 30 households,” MIT said in a statement about the discovery.
The lead-based cells are nearly as efficient as silicon-based cells used commercially today, the authors said, and recycled lead is just as effective as newly smelted lead.
“Cells made from perovskite have an efficiency of 19 to 20 percent,” said Po-Yen Chen, a graduate student of chemical engineering, who coauthored the paper.
Standard silicon-based cells have an efficiency ranging from 20 to 25 percent, Chen said.
Using car batteries as a source of lead for the panels benefits the environment in at least three ways: It recycles the neurotoxic heavy metal and keeps it out of landfills, it reduces the need for mining and smelting, and it creates sustainable, nonpolluting energy.
Environmental contamination from car-battery lead is a “global pollutant” that is especially acute in the developing world,” according to the Blacksmith Institute, a nonprofit group that works to clean up highly polluted sites where children are most at risk.
Used car batteries are shipped to cities in the developing world. “Recycling and smelting operations are usually conducted in the open air, in densely populated urban areas, and often with few (if any) pollution controls [that] release lead contaminated compounds into the local environment in critical quantities,” the Blacksmith Institute stated on its website.
In the United States, car batteries are the primary source of lead pollution, according to a study conducted in 2003 by the Michigan-based Ecology Center and the Environmental Defense Fund. The report found that the North American automobile industry contributes to the release or transfer of more than 300 million pounds of lead annually due to mining, smelting, manufacturing, recycling, and disposal, as well as normal vehicle use.
More than 200 million lead-acid batteries could be retired in the near future as automakers switch to new technologies, Chen said.
“When the perovskite cells came out three years ago, we saw they were made of lead, and we got the idea to use car batteries,” said Chen. “We were thinking of how to make the cells without harvesting more lead from the environment.”
A video of the team building a prototype solar panel from a car battery can be viewed here.
“From a general perspective, the concept is very appealing,” said Bob Gibson, a spokesperson for the Solar Electric Power Association. “A big question will be in what it will take to bring this to commercial production and at a price point where it can compete with silicon” solar panels.
Two companies are trying to commercially develop the battery-to-solar-cell technology, according to Chen. “The process is much simpler compared to silicon cells, and you don’t need an expansive facility,” he noted. “The process is expected to be cheaper, so the product would be too.”