Research by Rensselaer Polytechnic Institute published in Nature Communications has suggested that creating a lithium-ion battery that can be charged in a matter of minutes without compromising the capacity. This research is indicative of the potential to improve battery performance for consumer electronics, electric vehicles, and grid storage. A lithium-ion battery charges and discharges as lithium ions shift between the anode and the cathode. In a standard lithium-ion battery, the anode is made of graphite, while the cathode is made of lithium cobalt oxide. These materials work together, which is why the batteries are becoming increasingly popular, but the team at the institute believe that function can be enhanced more. They are working to improve the materials used for the electrodes.
The team has improved the performance capacity by substituting cobalt oxide with vanadium disulfide (VS2). The alteration makes it lightweight results in high energy density and high conductivity that helps it charge faster. Although the possible applications of VS2 have been appealing to scientists in the field, the compound is unstable, which will result in shorter battery lives. The latest research has not only identified the cause of this instability but might also have a potential solution. The team concluded that lithium insertion resulted in an asymmetry in the space between vanadium atoms, a phenomenon also known as Peierls distortion that breaks up the VS2 flakes. The group learned that coating the flakes with titanium disulfide (TiS2) creates a “buffer layer” on the VS2 material. The compound is unaffected by the distortion and stabilizes the VS2 flakes thereby enhancing the performance of the battery.
After this issue was resolved, it was found that the VS2-TiS2 electrodes were operating with a higher capacity and were able to store a lot of charge per unit mass. The resulting battery is small in size, which can create compact batteries. The batteries can be beneficial in enhancing car batteries, solar energy storage and power for portable electronics, where high capacity and increased charging speed are needed.
