Using materials from alfalfa (lucerne seed) and pine resin along with a clever recycling strategy, researchers have come up with a novel alternative to transform present-day lithium batteries.
"We think our discovery can open several doors to more environment-friendly, energy-efficient solutions for the batteries of the future," said co-researcher Daniel Brandell, associate professor at the Uppsala University in Sweden.
The battery is based on renewable biological material with an energy content corresponding to that of current lithium-ion batteries.
Components of the battery are made of renewable organic bio-materials from alfalfa and pine resin, and can be recycled with a low energy input and non-hazardous chemicals, such as ethanol and water.
Constructing a new battery from a spent one is also feasible. In other words, a straightforward process enables it to be reused, the researchers said.
The lithium extracted from a spent battery can be used for a new battery: all that needs to be added is bio-material, the findings showed.
The new battery proved capable of delivering as much as 99 percent of the energy output from the first.
With future modifications, this figure can very probably become even higher, the researchers noted.
Lithium-ion batteries are, thanks to their high energy content, highly promising for various products in the future energy system.
But the world's commercially extractable lithium resources are limited and whether they can meet future needs is unclear.
Moreover, it is very difficult to recover lithium from the inorganic materials used to make modern batteries.
The study is forthcoming in the journal ChemSusChem.