“Simplify, then add lightness. Adding power makes you faster on the straights. Subtracting weight makes you faster everywhere,” said Colin Chapman, the founder of Lotus Cars, explaining the light-weighting trend in cars.
It is especially important in designing electric cars because the lighter the weight of the chassis leads lower battery weight, and the battery is the heaviest part of an electric car.
Moreover, the range is a key factor in electric cars, and lesser weight leads to longer range between recharges. According to the US Department of Energy, reducing a car’s weight by 10% gives an additional 8% miles per gallon.
Thus, it is essential for electric cars to be lighter, stronger, and faster so they can meet strict emissions, fuel economy, and safety standards while remaining favorable to consumers. As Paolo Martino, an analyst at IHS Markit, said, “There is a rush to try and cut as much weight as possible, especially on cars which will pollute more, like SUVs or pick-up trucks.”
Aiming for car light-weighting, researchers from Japan’s Kyoto University is venturing on fabricating vehicle components out of wood pulp and plastic. The resulting composite material is as strong as steel but 80% lighter. The research team, headed by Professor Hiroyuki Yano, conducts a chemical treatment to wood pulp to break it down to millions of cellulose nanofibers. These nanofibers are then dispersed and incorporated into a plastic to constitute a cellulose-nanofiber-plastic composite material, which has a strength five times greater than the steel used in automobiles.
Aside from these properties of the cellulose-nanofiber-plastic composite material, Professor Yano adds that the production costs will also be reduced to one-fifth, “This is the lowest-cost, highest performance application for cellulose nanofibers, and that’s why we’re focusing on its use in auto and aircraft parts.” Compared to carbon fibers, which are currently being used in light-weighting, the cellulose-nanofiber-plastic composite material could also be cheaper.
The research team is working together with automobile manufacturer to assess if the technology is commercially feasible.