Carbon Fiber Coated MnO2 As Sulfur Carrier for Lithium Sulfur Battery

Carbon fiber derived from bacterial cellulose (BC) is used to load sulfur for lithium sulfur battery, when it is modified by MnO2. The composite material is characterized with scanning electron microscopy (SEM), X-ray diffraction (XRD) and thermogravimetric analysis (TGA), while its electrochemical performance tests are carried out at different current density. Compared to sample without MnO2, the as-designed material deliver much better electrochemical performance. The initial specific capacity of as-prepared M-pBCS composite is 894 mAh g-1 at 0.1C. After 100 cycles at 1C, the samples also deliver specific capacity of 668 mAh g-1. Besides, the sample also shows an improved rate performance than its counterpart at a rate range from 0.1C to 2C. Three dimensional (3D) network carbon fiber derived from bacterial cellulose can improve conductivity of electrode material. Moreover, MnO2 plays a role to adsorb polysulfide chemically. The special design can effectively alleviate shuttle effects of polysulfide.