Carbon Wrapping Effect on Sulfur/Polyacrylonitrile Composite Cathode Materials for Lithium Sulfur Batteries

Abstract

A sulfur-Polyacrylonitrile (PAN)-acetylene black (AB) composite was synthesized via thermal treatment processes. The as-prepared ternary composite was characterized by expending transmission electron microscopy (TEM), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) and electrochemical investigations. The improved electrochemical performance can be attributed to the formation of PAN layer, which can keep a tight contact between carbon and sulfur which leads to improve the conductivity. Moreover, the PAN can also act as a flexible cushion to accommodate volume changes of sulfur cathode as well as a barrier to trap soluble polysulfide intermediates during the charge-discharge process. The PAN-S-AB composite exhibits discharge capacity of 620 mAh/g even after 50 cycles with appreciable sustainability. Therefore, the resulting PAN/S/AB composite exhibited as a desirable cathode material for Li-S battery with great performance.

Graphene oxide-crowned poly(acrylonitrile)/sulfur as a lithium–sulfur battery cathode: performance and characterization

“…The I D /I G Fig. 4 a-d SEM image of the ternary PAN/S/GO composite (inset) EDX analysis of PAN/S/GO is 1.1, suggesting that the GO in the sample has a high degree of defects, which can offer additional energetic sites to facilitate diffusion of Li ions [22]. The Raman spectral results indicate a uniform distribution of sulfur particles in the composite, consistent with our XRD analysis.…”

“…The cell delivers a reversible capacity of 1096 mAh g −1 at 0.2 C, confirming a high reversibility and rate capability of the PAN/S/GO composite. The PAN matrix can not only accommodate the mechanical stresses induced by volume changes of the cathode at repeated cycles, but can also facilitate the ions transportation during cycling, leading to efficient cycling performance and rate capability [22]. The upgraded electrochemical kinetics of PAN/S/GO is supported by electrochemical impedance spectroscopy (EIS) measurements (Fig.…”

Sulfur‐Composites Derived from Poly(acrylonitrile) and Poly(vinylacetylene) – A Comparative Study on the Role of Pyridinic and Thioamidic Nitrogen

“…This is in stark contrast to conventional S/C composites, in which the mass loss stemming from S‐evaporation is often nearly quantitatively completed at approx. 400 °C due to the high volatility of elemental sulfur [29] …”

Sulfur/PAN/acetylene black composite prepared by a solution processing technique for lithium–sulfur batteries

“…The PAN matrix can not only facilitate the ions transportation during cycling, but can also accommodate the mechanical stresses induced by volume changes of the cathode at repeated cycles, leading to an excellent rate, and cycling performance . The retention of polysulfide species in the cathode matrix is further aided by the polymer.…”