New Materials Can Dramatically Increase Lithium-ion Battery Capacity

The American researchers have designed a new material that is expected to be used to make stable, high-capacity lithium-ion batteries, extending more than double the current lifespan of smart phones and electric vehicles. The Northwestern University of the United States issued a press release a few days ago that the new material is lithium magnesium oxide doped with chromium and vanadium.

The use of the lithium-magnesium oxide as a positive electrode of a lithium-ion battery can greatly increase the capacity of the battery and provide stable performance without rapid degradation. Lithium-ion batteries generally use lithium, oxygen, and a transition metal compound as the positive electrode, in which the transition metal is responsible for storing and releasing electric energy, and its nature determines the capacity of the battery. Cobalt is currently used. Previous studies have found that replacing cobalt with magnesium can increase capacity and reduce costs, but the battery performance degrades too quickly and decreases dramatically after two rounds of charge and discharge.

The research team of Northwest University published a paper in the United States "Scientific Progress" magazine that they established a detailed model of single atoms for lithium magnesium oxide materials, analyzed the charge-discharge process, and found that oxygen also participates in the storage of electrical energy. The researchers then tried a scheme to incorporate different elements into lithium magnesium oxide, and calculated the energy storage of various mixtures. It was found that the incorporation of chromium and vanadium can achieve the stability while maintaining the large capacity of the battery. Next they will test the actual performance of the new material in the laboratory.