batteries made from trees power up electric vehicles

Tree-based batteries from lignin

Stora Enso, a renewable-materials company based in Helsinki, is powering up electric vehicles using batteries made from trees, specifically lignin. Trees are composed of 20 to 30 percent of lignin which is a binder that gives wood its stiffness and a reason it resists rotting. Lignin is a by-product of cellulose fiber production, and companies have long turned to and recycled it for their renewable source of carbon. Stora Enso picks it up as a bio-based alternative to fossil fuels and gas that drives vehicles these days.

images courtesy of Stora Enso

The company explains that lignin is separated from wood during the production of cellulose fibers. After extracting it out of the machines, the company refines the by-product into a fine carbon powder, which serves as an active material for the negative anode of the lithium-ion battery. The hard carbon powder is then used to produce electrode sheets and rolls which are then fused with positive electrodes, separators, electrolytes, and other components to transform them into a lithium-ion battery.

Lignode batteries

How does it work?

Stora Enso explains that a lithium-ion battery consists of a positive electrode, a cathode, and a negative electrode called an anode. ‘When a battery is charged, lithium ions in the cathode move into the anode, where they connect with the carbon particles and are stored until the battery is discharged – which is what happens when you use your electronic device,’ the company writes on its website.

The company notes that the material used in the batteries is often graphite carbon, whose emissions harm the environment and can contribute to the slow charging times of the batteries. By replacing this fossil-based graphite with hard and refined carbon from trees, electric vehicles can benefit from more environment-positive charging and more manageable electrification based on the current standards of living.

the hard carbon powder is then used to produce electrode sheets and rolls

Heading toward commercialization in Europe

Lignin-based carbon can be used in batteries including those used in consumer electronics, the automotive industry, and large-scale energy storage systems. Stora Enso says it is using dry lignin to manufacture Lignode, its batteries made from trees, and is planning to create a European supply chain for the lithium-ion battery industry.

The target is to offer what the company calls ‘the most sustainable and lowest-impact anode material available, to meet the eco-friendly mindset of future consumers. Our lignin has superior traceability with sustainable raw-material management certificates.’

lignin powder turned into a roll of carbon-driven sheet

Markus Mannström, Executive Vice President of Stora Enso’s Biomaterials division, comments on the company’s news that its pilot plant is now operating to supply and produce these batteries made from trees.

‘With Lignode, we can provide a bio-based, cost-competitive, and high-performance material to replace the conventionally used graphite. To serve the fast-growing anode materials market, we are now exploring strategic partnerships to accelerate scale-up and commercialization in Europe,’ he comments.