The electric vehicle market is developing rapidly. In order to extend the mileage of the vehicle, the demand for high -capacity batteries has continued to increase. It is reported that researchers at Postech (Postech) at the University of Korea have developed a functional polymer adhesive that can be used for stable and high -capacity negative materials, thereby increasing the current range of electric vehicles at least 10 times.
Compared with traditional graphite negative electrodes, the negative electrode material of this charged polymer adhesive can achieve a capacity of more than 10 times. This breakthrough is achieved by replacing graphite with a silicon negative electrode and combined with layered charged polymers, while maintaining stability and reliability.
It is very important for creating high -energy density lithium -ion batteries and high -capacity negative materials such as silicon. It can provide at least 10 times the capacity of existing graphite or other negative electrode materials. The challenge is that in the process of reaction with lithium, the volume of high -capacity negative materials is swollen, which pose a threat to battery performance and stability. To solve this problem, researchers have been exploring polymer adhesives that can effectively control volume expansion.
However, the current research is only concentrated in the combination of chemical cross -linking and hydrogen bonds. Chemical cross -linked covalent bonding between adhesive molecules. This makes them solids, but there is a serious defect. Once these keys are broken, they cannot be repaired. On the other hand, the combination of hydrogen bonds is a reversible two -key combination based on electrical negative differences between molecules, but the strength (10–65 kj/mol) is relatively weak.
The new type of polymer developed by the team not only uses hydrogen bonds, but also uses Klunli (gravity between positive negative charge). The strength of these forces is 250 kj/mol, which is much higher than the intensity of the combination of hydrogen bonds. Because it is reversible, it is easy to control volume expansion.
Most of the surface of the high -capacity negative material is mostly negative, and the layer -shaped charged polymer is arranged alternately with positive and negative charge, which can effectively combine the negative electrode. In addition, the team also introduced polyethylene glycol to regulate physical properties to promote lithium ion diffusion, thereby obtaining high -capacity thick electrodes in lithium ion batteries, and fully improved energy density.
