Systematic insight of the behavior of LiNO3 additive in Li-S batteries with gradient S loading

Previous studies revealed that LiNO3 can enhance the cyclic stability of lithium-sulfur (Li-S) batteries by creating a solid electrolyte interface protecting the lithium electrode. However, this study investigated the effect of LiNO3 and concentration in the electrolyte, first studied under low and high sulfur loading. It is confirmed that adding a small amount of LiNO3 inhibits the shuttle effect phenomenon in Li-S batteries, and the Coulombic efficiency was significantly improved. Appropriately increasing the concentration of LiNO3 to 2 % could prolong the cycle life. However, when LiNO3 is excessive, the rate and cycling performance decrease. The design of practical Li-S batteries requires more research on the parameters of electrolyte additives under high-sulfur -loading conditions. After gradient increasing the sulfur loading, the low concentration of LiNO3 cannot play the best performance of the battery, so it is necessary to improve the concentration of LiNO3 further. It is evident that adding LiNO3 in Li-S batteries has certain benefits, and the optimal amount of additive is related to the value of sulfur loading.