Rubber Journal Asia Materials News
Recycled carbon black to power electric vehicles? Yes, the possibility of recycled carbon black being used to power electric vehicles could be a reality. Old tyres have never had it so good. In a bid to divert them from the landfills, tyres are often recycled for use on basketball courts; new shoe products; in children’s playgrounds; as furniture, clothing and mats and many other uses. And now a research institute in the US has developed a novel idea that could see old tyres powering vehicles.
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he global battery market for vehicles and military applications is approaching US$78 billion and the materials market is expected to hit US$11 billion in 2018. One such contributor to the vehicle market could be recycled tyres that could see new life in lithiumion batteries for providing power to plug-in electric vehicles and store energy produced by wind and solar, say researchers at the US Department of Energy’s Oak Ridge National Laboratory (ORNL). By modifying the microstructural characteristics of carbon black, recovered from discarded tyres, a team led by Parans Paranthaman and Amit Naskar is developing a better anode for lithium-ion batteries. An anode is a negatively charged electrode used as a host for storing lithium during charging. The method has numerous advantages over conventional approaches to making anodes for lithium-ion batteries. “Using waste tyres for products such as energy storage is very attractive not only from the carbon materials recovery perspective but also for controlling environmental hazards caused by waste tyre stock piles,” Paranthaman said.
which exceeds the best properties of commercial graphite. Researchers attribute this to the unique microstructure of the tyre-derived carbon. Anodes are one of the leading battery components, with 11 to 15% of the materials market share, according to Naskar, who noted that the new method could eliminate a number of hurdles. “This technology addresses the need to develop an inexpensive, environmentally benign carbon composite anode material with high-surface area, higher-rate capability and long-term stability,” Naskar said. ORNL plans to work with the US industry to license this technology and produce lithium-ion cells for automobile, stationary storage, medical and military applications. The researchers are working on a pilot manufacturing process to scale up the recovery of material and demonstrate applications as anodes for lithium-ion batteries in large-format pouch cells. Researchers expect these batteries to be less expensive than those manufactured with commercial carbon powders. The research on conversion of recycled tyres to graphite powders was funded by the laboratory’s Technology Innovation Program while the research on battery fabrication and electrochemical testing was sponsored by DOE’s Office of Basic Energy Sciences, Materials Sciences and Engineering Division. Transmission electron microscopy research was supported by ORNL’s Centre for Nanophase Materials Sciences, a DOE Office of Science user facility.
Perfecting the technique for anodes he ORNL technique uses a proprietary pretreatment to recover pyrolytic carbon black material, which is similar to graphite but manmade. When used in anodes of lithium-ion batteries, researchers produced a small, laboratory-scale battery with a reversible capacity that is higher than what is possible with commercial graphite materials. In fact, after 100 cycles the capacity measures nearly 390 milliamp hours/g of carbon anode,
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