Carbon aerogels for cathodes of lithium-sulfur batteries

Kurzfassung

A high attention has been paid towards the exploitation of renewable energy resources and energy storage. Among the energy storage devices, lithium-sulfur batteries are very attractive because of their very high specific energy density about 2 500 Wh·kg-1 and very high theoretical specific capacity about 1 675 mAh·g-1 [1]. Moreover to its high theoretical specific capacity, sulfur is abundant on earth and inexpensive. With these benefits lithium-sulfur batteries are considered to be the next generation power source in advanced technologies e.g. electric vehicles. However, the poor cycle stability due of polysulfide shuttle and side reactions reduces the active mass quantity resulting in decrease of capacity. Carbon aerogels are a highly promising material to be used as matrix for sulfur to fabricate cathode for lithium-sulfur batteries. Resulting from organic resorcinol-formaldehyde aerogels, carbon aerogels exhibit highly porous structure with porosity up to 97%, high surface area about 500-3500 m²·g-1, large pore volume about 2-3 cm³·g-1, and good electronic conductivity [2, 3]. Additionally, the important advantage of carbon aerogel is its tunable porous structure and pore size distribution. In the presentation actual results will be pointed out. [1] M.-K. Song, E.J. Cairns, Y. Zhang, Lithium/sulfur batteries with high specific energy: old challenges and new opportunities, Nanoscale, 5 (2013) 2186-2204. [2] R.W. Pekala, J.C. Farmer, C.T. Alviso, T.D. Tran, S.T. Mayer, J.M. Miller, B. Dunn, Carbon aerogels for electrochemical applications, J. Non-Cryst. Solids, 225 (1998) 74-80. [3] R.W. Pekala, S.T. Mayer, J.L. Kaschmitter, F.M. Kong, Carbon Aerogels: An Update on Structure, Properties, and Applications, in: Y. Attia (Ed.) Sol-Gel Processing and Applications, Springer US, 1994, pp. 369-377.