Currently widely used Lithium ion batteries are based on metal oxides or phosphates and carbon systems with theoretical specific capacity of about 400 Wh/Kg. However to meet the ever growing energy demand of modern society, specifically for extended range electric vehicles, high energy density batteries are required [1, 2]. From this viewpoint, the use of sulfur as a cathode material is highly beneficial since its theoretical specific capacity corresponding to 1675 mAh/g could generate high energy density of 2600 Wh/Kg which is 3x10⁵ folds higher than the state-of-the art Lithium ion batteries [3]. However, research on lithium sulfur (Li/S) batteries using liquid electrolytes faces several problems such as the loss of the active material in the form of soluble polysulfide reaction products [4, 5]. Hence, for the development of next generation high performance power sources with high energy densities substantial emphasis has be laid on rechargeable all solid-state Li/S batteries. All solid state Li/S batteries include a solid electrolyte that offers several benefits such as good flexibility, potentially high electrochemical stability window and low flammability. The solid state nature could be very beneficial to Li/S batteries as they can prevent polysulfide dissolution and efficiently lessen dendrite penetration [6]. In this work, two kind of sulfur carbon composite electrodes were prepared by mechanical activation and thermal activation technique and the performance was evaluated by incorporating in a solid state battery. A composite solid polymer electrolyte prepared by dispersing the Li_1.3Al_0.3Ti_1.7(PO₄)₃ (LATP) ceramic fillers in the blend of high and low molecular weights polymer matrix was used as a solid electrolyte. The solid state battery using thermally activated composite electrode showed good electrochemical performance and cycle stability due to intimate contact between the sulfur and the carbon.

[1] Morris, R. Scott, et al. "High-energy, rechargeable Li-ion battery based on carbon nanotube technology." Journal of Power Sources 138.1 (2004): 277-280.

[2] Thackeray, Michael M., Christopher Wolverton, and Eric D. Isaacs. "Electrical energy storage for transportation—approaching the limits of, and going beyond, lithium-ion batteries." Energy & Environmental Science 5.7 (2012): 7854-7863.

[3] Aurbach, Doron, et al. "On the surface chemical aspects of very high energy density, rechargeable Li–sulfur batteries." Journal of the Electrochemical Society 156.8 (2009): A694-A702.

[4] Hayashi, Akitoshi, et al. "All-solid-state Li/S batteries with highly conductive glass–ceramic electrolytes." Electrochemistry communications 5.8 (2003): 701-705.

[5] Kobayashi, Takeshi, et al. "All solid-state battery with sulfur electrode and thio-LISICON electrolyte." Journal of Power Sources 182.2 (2008): 621-625.

[6] Machida, Nobuya, et al. "Electrochemical properties of sulfur as cathode materials in a solid-state lithium battery with inorganic solid electrolytes." Solid State Ionics 175.1 (2004): 247-250.