Methods to improve the performance of lithium-sulfur battery -Lithium - Ion Battery Equipment
After 50 charging cycles, the capacity density of the lithium-sulfur battery drops rapidly, which is mainly due to the dissolution and volume expansion of Li2Sn (4≤ n≤ 8) as a medium and the low conductivity of sulfide and polysulfide compounds.
The first method is to stabilize sulfur: researchers use amylopectin, a polysaccharide, which is an essential component of corn starch. A three-dimensional cross-linked structure was prepared from a compound coated with amylopectin (GO-S-Amy).
With this cross-linked structure, the sulfur particles in graphene oxide are effectively controlled, and compared with the uncoated compound (GO-S-Amy), the recyclability is also greatly improved.
Another way is to improve the durability of lithium-sulfur batteries: by heating and curing polyaniline sulfur with core-shell structure, the hollow core-shell structure of nano-compound (S-Pani) is obtained.
The researchers found that compared with the chemical leaching method, the heating method can obtain more average hollow core-shell structure. In addition, the circularity of hollow core-shell nanostructures has been greatly improved because the voids in the polymer shell can accommodate the volume expansion of sulfur during the lithification reaction.(Lithium - Ion Battery Equipment)
The stability of hollow core-shell structure material is still very high after 200 times of charging. From a chemical point of view, this polyaniline coating is a chain-like structure formed by stringing benzene ring and ammonium base. It is soft and flexible, and can make the shell not crack in the long-term cycle process.