Can car batteries be recycled into solar panels?
Good news: Scientists have come up with a way to recycle the same batteries (or rather the lead) into new long-lasting solar panels which provide emissions-free power.
The win-win solution is based on developments in solar cells which makes use of a compound called perovskite – now as efficient as other methods for use in solar panels – which relies on lead.
The system is described in a paper in the journal Energy and Environmental Science, co-authored by MIT professors Angela M Belcher and Paula T Hammond, graduate student Po-Yen Chen, and three others.
Just one problem: to use perovskite would involve sourcing lead and its production from raw ore can produce toxic residues – not great when you’re trying to create emissions-free power.
But by using the lead from the old car batteries it stops that lead from going to landfills and saves more from having to be created.
And the resulting photovoltaic panels could go on producing power for decades.
Amazingly, because the perovskite photovoltaic material takes the form of a thin film just half a micrometre thick, the MIT team’s analysis shows that the lead from a single car battery could produce enough solar panels to provide power for 30 households.
And carrying on the win-win matra: 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, says Belcher, the WM Keck professor of energy at MIT.
Those factors will help to make it “easy to get to large scale cheaply,” Chen adds.
And there’s no shortage of lead-acid batteries because in the car industry that technology is being replaced with 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 says.
Currently 90% of the lead recovered from the recycling of old batteries is used to produce new batteries, but over time the market for new lead-acid batteries is likely to decline, potentially leaving a large stockpile of lead with no obvious application. Until now!
In a finished solar panel, the lead-containing layer would be fully encased by other materials, limiting the risk of lead contamination of the environment. When the panels are eventually retired, the lead can simply be recycled into the next generation of solar panels.
Keen to know more? See all the details in this seven-minute video from the team.
