Key Words:Lithium sulfur batteries;Cathodes - Electric batteries - Electrodes - Energy storage - Lithium - Lithium batteries - Lithium compounds - Porous materials - Pyridine - Secondary batteries - Sound insulating materials - Sulfur - Synthesis (chemical);Capacity fading rates - Electrochemical energy storage - Energy storage and conversions - Functional - High energy densities - Initial discharge capacities - N content - Porous g-C3N4
Abstract:Lithium-sulfur battery has become to be one of the most promising electrochemical energy storage systems on account of the high theoretical specific capacity (1673 mAh/g) and high energy density (2600 Wh/kg). However, the relatively complicated producing process of the host materials and lithium-sulfur battery’ cycling instability still hinder the commercialization of Li-S battery. Herein, a facile, inexpensive and scalable thermal treatment method was designed to synthesize the host material porous g-C<inf>3</inf>N<inf>4</inf>composed by graphite-like two-dimensional rippled sheets and high content of pyridine N, improving the properties of Li-S batteries. Because of the high charge polarity and peculiar porous structure, the porous g-C<inf>3</inf>N<inf>4</inf>/S cathode delivered high initial discharge capacity of 1050 mAh/g. Furthermore, it possesses excellent cycling stability for 200 cycles with a low capacity fading rate of 0.2% per cycle at 0.1C and a high-rate capacity of ∼400 mAh/g even at 1C rate. Therefore, this study presents a new enlightenment for researchers to realize the practical application of Li-S batteries and an effective reference for the design of other porous materials.<br/> © 2017 Elsevier B.V.
Volume:213
Issue:无
Translation or Not:no