(585al) Integrated Design of Sulfur Host Materials to Enhanced the Performance of Li-Sulfur Batteries

Lithium–sulfur batteries (LSBs) are considered as a promising candidate for next generation electrical energy storage systems, because they can deliver a significantly higher theoretical energy density of 2600 Wh/kg compared to lithium ion batteries (LIBs), and offer intriguing structural advantages, such as very high specific theoretical capacity (1675 mAh g^-1), low cost, and nontoxicity. Despite of multiple advantages of LSBs, they still suffer from some significant challenges, including low electrical conductivity of sulfur, fast capacity fading at high discharge rate, and low Coulombic efficiency due to the shuttle effect from polysulfides ions. The insulating nature of sulfur, the dissolution of intermediate polysulfides and final Li₂S products affecting the utilization rate of active sulfur, lead to low specific capacity. Particularly, the big stone for LSBs is the redox reactions of polysulfides at both the cathode and anode surfaces, caused by the dissolution of the reaction intermediates in the organic electrolyte, which consume a large proportion of the capacity. In order to overcome the aforementioned issues we have designated various metal/metal oxide-carbo hybrid sulfur host materials that have the ability to efficiently restrained polysulfides via both structural restriction and chemical encapsulations effect. The developed sulfur host have enhanced the performance of LSBs in term of capacity, rate capability and cyclability.

References: