- Category: Conference Presentations, Posters, and Proceedings
Abstract for “Development of Lithium Sulfur Cells for Portable Power Applications”
The development of a rechargeable battery with high energy density is of considerable technological importance because of the increasing energy consumption of portable devices. Elemental sulfur is very attractive as a cathode material for rechargeable batteries because of its high theoretical specific capacity of 1670 mAh/g. The main challenges are the non-conductive nature of sulfur/polysulfides which demands sufficient amount of carbon in the cathode thereby limiting the amount of active material. In addition to that, there is gradual loss of sulfur from the cathode during discharge by means of polysulfide dissolution. As a result, lithium sulfur chemistry generally suffers from low volumetric capacity, poor rate capability and cycle life. We have developed an advanced sulfur composite cathode by entrapping sulfur/polysulfide in the internal pores of carbon and achieved high rate capability. Our proprietary electrolyte formulation further extended the cycle life and coulombic efficiency by minimizing irreversible loss of polysulfide due to shuttling. It also improved the shelf life and intermittent discharge capacity. EPT’s ion selective nanoclay modified separator which functions as conductive reservoir of polysulfides further extended the discharge capacity for practical applications.