by Gage Taylor
These days, it seems rare that a week passes where we don’t hear about some new kind of exotic or outlandish approach to electric car construction. With technology moving at a breakneck pace and interest in the field at an all-time high, concerns over range, power delivery, and cost are to be expected. But where most announcements seem to revolve around nanotechnology or other synthetic materials, a team of researchers from the KTH Royal Institute of Technology in Sweden announced this week that they’d constructed a small-scale model of an electric vehicle battery pack made from wood. By developing a new carbon-fiber material which has lignin, a natural polymer found in nearly every dry-land plant on earth, as its main ingredient, they’ve made a big step toward cheaper, more energy-dense batteries.
Most carbon fiber production techniques in use today are expensive, time-intensive processes. Traditionally relying on spinning synthetic polymers from substances like rayon, polyacrylonitrile, or petroleum pitch, the process requires massive amounts of energy to drive off non-carbon atoms and form the strong molecular bonds characteristic of the material. From there, the fibers are often mixed with polymer resins to create reinforced plastic.
The KTH team’s approach, though, is rather different, relying on the natural material of lignin. Found in the support tissues and cell walls of vascular plants, it’s the second most common organic polymer on earth. More than 1.1 million metric tons of the material are produced each year already, most of it as a byproduct from making paper pulp. Given the material’s abundance and incredible strength, it’s a no-brainer as a cost-effective alternative to synthetic materials.
While the KTH team is still far from fully developing the technology, their model, created in cooperation with the Swedish research institute Innventia and industrial renewal group Swerea, proves the validity of the process, utilizing both a battery and a roof made with the Lignin-based carbon-fiber. Göran Lindeberg, Professor of Chemical Engineering and leader of the project, is optimistic that the material will eventually be used to both store electrical energy and provide structural integrity for vehicles, reducing costs and energy expenditure in the process. As already demonstrated by BMW’s extensive use of carbon-fiber reinforced plastic, structural use of carbon-fibers can dramatically lower vehicle weight and thus increase fuel efficiency. If the lignin-based material can jump through the hoops required to become consumer technology, the whole process could become a much cheaper prospect.
KTH Royal Institute of Technology. “Carbon fibre from wood is used to build car.” [https://www.kth.se/en/forskning/artiklar/framtidens-bilar-byggs-av-tra-1.623626]
Gordon-Bloomfield. . “Could a Byproduct of Paper Pulp Production Make Electric Car Batteries Lighter? Yes, Says Swedish Research Team.” [https://transportevolved.com/2016/02/10/could-a-byproduct-of-paper-pulp-production-make-electric-car-batteries-lighter-yes-says-swedish-research-team/]