New Cell Configuration with Carbon Interlayers for High Cycle Stability Lithium Sulfur Batteries

Lithium sulfur batteries are the most promising next-generation energy storage system due to their high energy density and low cost^[1]. Although the studies on Li-S batteries have been ongoing over many years, commercialization of Li-S battery has not been successful due to many problems including the significant capacity fading.

The diffusion of polysulfides causes fast capacity decay of Li-S battery^[2]. In this work, a well-designed carbon interlayer was used between the separator and the sulfur electrode for accommodating the migration of polysulfides during cycling. This Li-S cell configuration delivers excellent cycle stability, retaining a reversible discharge capacity of 850.7mAh·g^-1 after 50 cycles with a retention rate of 80.5% when the sulfur loading of the cathode is 5.2mg·cm^-2(Figure 1). The result indicates that this configuration is highly practical for the lithium sulfur batteries.

References:

[1]P.G.Bruce, S.A.Freunberger, L.J.Hardwick, and J.M.Tarascon, Nature materials., 11, 19(2011).

[2] Y. Yang, G. Zheng, and Y. Cui, Chemical Society Reviews., 42, 3018(2013).