A research team at the Korea Institute of Science and Technology (KAIST) has developed an ultra-stable, high-rate lithium-sulfur battery. The research team uses hierarchical porous titanium nitride (h-TiN) as a sulfur host. . The research team wrote in the paper that when the ambient temperature is 5 ° C, the battery is charged and discharged 1000 times. The reversible capacity of h-TiN / S is about 557 mAh / g, and the capacity per charge and discharge declines. The rate is only 0.016%.
To cope with this kind of problem, Jinwoo Lee, a professor in the Department of Chemistry and Biomolecular Engineering, and his team synthesized a more developed macroscopic / mesoporous titanium nitride as a host material for sulfur.
Titanium nitride has a high chemical affinity for sulfur and high electrical conductivity, which prevents dissolution of the active material and assists in charge transfer. In addition, the synergistic effect of the macroporous and mesoporous structures can stably contain a large amount of sulfur, and assist in electrode penetration.
Earlier reports mentioned that the polar inorganic materials have a high chemical affinity for sulfur, but have insufficient ability to control the sulfur host porous structure. Now, this research has developed a new synthetic route, which is simpler to control the porous structure of inorganic materials, and breaks through the above technical limitations, so as to obtain excellent cycling (charge and discharge) stability and high charging rate.