화학공학소재연구정보센터
Journal of the Electrochemical Society, Vol.166, No.15, A3869-A3873, 2019
Promoting Redox Reduction of Lithium-Sulfur Battery by Tris(2-carboxyl)phosphine Shearing S-S Bond
Lithium sulfur (Li-S) battery is equipped with high energy density, resulting from multistage redox reaction of the complex sulfur electrochemistry. Due to the slow redox kinetics of polysulfide intermediates induced shuttle effect and reduced cycling life. In order to restrain thermodynamic shuttle effect from the source, a new-type reductive functional Tris(2-carboxyethyl)phosphine aramid paper (TCEP-AP) interlayer was incorporated into battery. The phosphophilic ester of TCEP was used to shear the s-s bonds and accelerated redox reactions of polysulfides. Meanwhile, the porous 3D MWCNTs aramid paper can effectively trap polysulfides and provide efficiently conductive pathways. The work indicated that TCEP-AP can be an especially effective agent to cut polysulfides and improved the electrochemical performance of Li-S batteries. The initial discharge capacity reached 1544 mAh g(-1) for S-TCEP-AP Li-S batteries at 0.1 C. The remarkable cycling stability was obtained, the high reversible capacity of 609 mAh g(-1) with negligible fading rate of 0.029 % per cycle at 1 C were obtained after 400 cycles. (C) 2019 The Electrochemical Society.