The renewable energy economy needs batteries for everything from electric cars to solar energy storage. But current lithium-ion batteries aren’t exactly environmentally friendly–especially when they wear out, since the materials inside shouldn’t go in the trash and are energy-intensive to recycle.
Swedish researchers have come up with one possible alternative: A new battery made partly from alfalfa and pine resin instead of rare metals like cobalt or nickel.
“Current lithium-ion batteries can be recycled, but demand high energy processing and harsh chemical treatment,” explains Uppsala University’s Daniel Brandell. Lithium itself isn’t recovered at all, he says, since the process takes so much energy and lithium isn’t worth enough.
The new battery is simple to recycle without toxic chemicals or huge amounts of energy. “We use low temperatures and extraction in easy and non-toxic solvents like water and ethanol,” Brandell says.
The process makes it possible to recover 99% of the lithium and then turn it back into a new battery, just by adding more of the renewable materials. As the market for lithium-ion batteries is expected to expand by as much as 400% in the next six years, fueled by growing demand from car manufacturers and utilities, recycling could help keep prices low and reduce the need for mining.
Extracting the battery’s key materials from alfalfa and pine resin also makes it possible to avoid mining rare metals like cobalt and nickel. The renewable materials also take far less energy to manufacture, and will likely help bring down the cost of the batteries.
The researchers hope that the new batteries could be ready for the market in a couple of years, after further tweaking the chemistry to make the batteries as competitive as possible.
“Our battery can sustain a few hundred cycles, which is good, but with the right processing, it could be more than one thousand,” Brandell says. “To achieve this goal, it might take approximately one to two years, if we get involved with a proper li-ion battery manufacturer.”