A team of researchers led by Dr. Hun-Gi Jung at Korea Institute of Science and Technology’s (KIST’s) Center for Energy Storage Research developed a new carbon-silicon anode material that can increase battery capacity four-fold compared to graphite anode materials. When applied to batteries for EV, it can more than double the driving range and enable fast charging to over 80% in merely five minutes.
Electric vehicles (EV’s) on the roads today typically use graphite anode batteries. While great for the environmental issue of carbon emissions, these batteries have a low capacity for energy, so they tend to provide a shorter range compared to cars with internal combustion engines that run on gasoline. Silicon anodes have an energy storage capacity ten times greater than graphite but are worse at holding their capacity over time. Nevertheless, the potential is there, so the material has been the focus of next-generation anode material studies intent on developing long-range electric vehicles.
Dr. Jung’s team found a simple way to enhance the stability of silicon by using a thermal process used for frying food. They used ordinary, everyday materials – water, starch, and oil. The starch they dissolved in water and the silicon in oil. Then, they mixed and heated them to produce carbon-silicon composites. Lastly, they put the composites through a thermal process that firmly fixed the carbon and silicon, making it so the silicon anode materials can’t expand during charge and discharge cycles.
Dr. Jung said:
We were able to develop carbon-silicon composite materials using common, everyday materials and simple mixing and thermal processes with no reactors. The simple processes we adopted and the composites with excellent properties that we developed are highly likely to be commercialized and mass-produced. The composites could be applied to lithium-ion batteries for electric vehicles and energy storage systems (ESSs).
The result is a battery that has four times the capacity of graphite anode and remains stable over 500 cycles, spelling a vast improvement for EV range. The research was recently published in the journal Nano Letters.
