Dr. Hun-Gi Jung of the Korea Institute of Science and Technology (KIST) Energy Storage Research Center and his research team announced that they have developed a new silicon anode material. Compared with graphite anode materials, batteries using this material can increase capacity by 4 times, and support fast charging, charging to more than 80% within 5 minutes. If used in electric vehicle power batteries, it is expected that the cruising range of the car will more than double.
At present, the capacity of graphite anode materials used in mass production of electric vehicle batteries is relatively low, and the range of electric vehicles is shorter than that of internal combustion engines. In order to develop long-range electric vehicles, people are increasingly paying attention to silicon, which has a storage capacity 10 times greater than graphite, and regard it as the next-generation anode material. However, due to the rapid expansion of silicon during the charge and discharge cycle, resulting in a significant decrease in storage capacity, silicon materials have not yet been commercialized. Researchers have proposed many methods to improve the stability of silicon anode materials. Due to the high cost and the complexity of the process, the goal of replacing graphite with silicon cannot be successfully achieved.
To improve the stability of silicon, Dr. Jung and his team focused on the common materials in life, such as water, oil and starch. They dissolved starch and silicon in water and oil, respectively, and mixed heating to produce carbon-silicon composite materials. Through a simple fried food heating process, carbon and silicon are firmly fixed to prevent the expansion of the silicon anode material during the charge and discharge cycle.
The composite material developed by the research team has a capacity four times that of the graphite anode material (360mAh / g-1,530mAh / g), and can maintain the capacity stable for 500 cycles. The study also found that batteries using this material can be charged to more than 80% in 5 minutes. Because carbon balls can prevent the expansion of common silicon materials and improve the stability of silicon materials; and the use of highly conductive carbon and rearrangement of silicon structures can increase output.
Dr. Jung, the principal researcher of the KIST team, said: "We can use common daily materials to develop carbon-silicon composite materials through a simple mixing and heating process. We use a relatively simple process and the developed composite materials Excellent performance, therefore, it is very promising to achieve commercialization and mass production. This composite material can be used in lithium-ion batteries and energy storage systems for electric vehicles. "