Novel Porous Complex Framework Materials (CFM) Based Sulfur Hosts for High Energy Density Li – S Batteries

Abstract

Research to date has focused on improving the performance of conventional Li-ion batteries. Sulfur has been correspondingly identified as a promising cathode material. Li-Sulfur (Li-S) batteries exhibits a theoretic specific capacity if 1672 mAh/g1-2 as opposed to that of conventional cathode-based Li-ion batteries (372 mAh/g)3. Sulfur is also a relatively inexpensive and abundant material that adds to the advantages of the Li-S batteries4. However, the poor ionic and electronic conductivity (~10-30S/cm)5 of sulfur greatly limits its utilization during the electrochemical cycling process, in addition to the formation of non-insertion based polysulfide intermediates(Li2Sn ; n = 2 – 8)6. These polysulfide intermediated are extremely soluble in the organic Li-S battery electrolyte leading to loss of active material and fade in capacity eventually leading to cell failure. Reduction of polysulfide dissolution is the primary focus of current Li-S battery research along with improving the ionic and electronic conductivity of sulfur. Polysulfide dissolution was reduced considerably by hosting sulfur into various porous carbonaceous materials7-12. These porous hosts act as polysulfide traps and help reduce the polysulfide diffusion and dissolution into the electrolyte. However, the porosity and architecture of these materials need to be engineered comprehensively in order to completely prevent polysulfide dissolution and meet the high sulfur loading (>6mg/cm2) requirements of the DOE Batt500 program. In this work, novel highly porous carbonaceous materials with engineered porosity and mesoporous architectures have been identified to serve as effective high sulfur loading (~4-6 mg/cm2) cathodes with unique carbon-sulfur chemical interactions. These porous and engineered chemically bonded structures help improve the conductivity of the cathode along with the prevention of polysulfide dissolution. Detailed results of the chemical and electrochemical characterization of these materials will be presented and discussed. References Akridge, J. R.; Mikhaylik, Y. V.; White, N., Li/S fundamental chemistry and application to high-performance rechargeable batteries. Solid State Ionics 2004, 175 (1–4), 243-245.Ji, X.; Nazar, L. F., Advances in Li-S batteries. Journal of Materials Chemistry 2010, 20 (44), 9821-9826.Yang, H.; Zhuang, G. V.; Ross, P. N., Thermal stability of LiPF6 salt and Li-ion battery electrolytes containing LiPF6. Journal of Power Sources 2006, 161 (1), 573-579.Li, G. C.; Hu, J. J.; Li, G. R.; Ye, S. H.; Gao, X. P., Sulfur/activated-conductive carbon black composites as cathode materials for lithium/sulfur battery. Journal of Power Sources 2013, 240, 598-605.Kim, J.; Lee, D. J.; Jung, H. G.; Sun, Y. K.; Hassoun, J.; Scrosati, B., An Advanced Lithium‐Sulfur Battery. Advanced Functional Materials 2013, 23 (8), 1076-1080.Lin, C.-N.; Chen, W.-C.; Song, Y.-F.; Wang, C.-C.; Tsai, L.-D.; Wu, N.-L., Understanding dynamics of polysulfide dissolution and re-deposition in working lithium–sulfur battery by in-operando transmission X-ray microscopy. Journal of Power Sources 2014, 263, 98-103.Chen, S.-R.; Zhai, Y.-P.; Xu, G.-L.; Jiang, Y.-X.; Zhao, D.-Y.; Li, J.-T.; Huang, L.; Sun, S.-G., Ordered mesoporous carbon/sulfur nanocomposite of high performances as cathode for lithium–sulfur battery. Electrochimica Acta 2011, 56 (26), 9549-9555.Ahn, W.; Kim, K.-B.; Jung, K.-N.; Shin, K.-H.; Jin, C.-S., Synthesis and electrochemical properties of a sulfur-multi walled carbon nanotubes composite as a cathode material for lithium sulfur batteries. Journal of Power Sources 2012, 202, 394-399.Guo, J.; Xu, Y.; Wang, C., Sulfur-Impregnated Disordered Carbon Nanotubes Cathode for Lithium–Sulfur Batteries. Nano Letters 2011, 11 (10), 4288-4294.Shanthi, P. M.; Hanumantha, P. J.; Gattu, B.; Sweeney, M.; Datta, M. K.; Kumta, P. N., Understanding the Origin of Irreversible Capacity loss in Non-Carbonized Carbonate − based Metal Organic Framework (MOF) Sulfur hosts for Lithium − Sulfur battery. Electrochimica Acta 2017, 229, 208-218.Murugavel Shanthi, P.; Jampani Hanumantha, P.; Albuquerque, T.; Gattu, B.; Kumta, P. N., Novel Composite Polymer Electrolytes (CPEs) of PVdF – HFP derived by Electrospinning with Enhanced Li-ion Conductivities for Rechargeable Lithium – Sulfur batteries. ACS Applied Energy Materials 2018.Hanumantha, P. J.; Gattu, B.; Shanthi, P. M.; Damle, S. S.; Basson, Z.; Bandi, R.; Datta, M. K.; Park, S.; Kumta, P. N., Flexible sulfur wires (Flex-SWs)—A new versatile platform for lithium-sulfur batteries. Electrochimica Acta 2016, 212, 286-293.