Acta Phys. -Chim. Sin. ›› 2017, Vol. 33 ›› Issue (5): 968-975.doi: 10.3866/PKU.WHXB201702093

• ARTICLE • Previous Articles     Next Articles

Preparation of Biochar from Different Biomasses and Their Application in the Li-S Battery

Jun-Tao LI1,*(),Jiao-Hong WU1,Tao ZHANG1,Ling HUANG2   

  1. 1 College of Energy, Xiamen University, Xiamen 361005, Fujian Province, P. R. China
    2 College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian Province, P. R. China
  • Received:2016-12-28 Published:2017-04-20
  • Contact: Jun-Tao LI E-mail:jtli@xmu.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(21373008);Fundamental Research Funds for the Central Universities, China(20720160124)

Abstract:

Biochar derived from reproducible massive biomasses presents the advantages of low cost and renewable resources. In this work aiming to solve the existing problems of the lithium-sulfur battery, sulfur@biochar (S@biochar) composite cathode materials with high capacity and good cycle performance were developed. Specifically, four kinds of biochar prepared from rice husk, miscanthus, fir, and pomelo peel were used as host matrices for the Li-S battery. Among them, the S@biochar derived from rice husk delivered the highest specific capacity and the best cycle stability according to electrochemical tests. To further optimize its performance, we prepared a highly porous rice husk derived biochar (HPRH-biochar) using silica gel as the template. The S@HPRH-biochar composite (60% (w, mass fraction) S) enables the homogeneous dispersion of amorphous sulfur in the carbon matrix and its porous structure could effectively suppress the dissolution of the polysulfide. As a result, its electrochemical performance improved, achieving a high initial charge capacity of 1534.1 mAh·g-1 and maintaining a high capacity of 738.7 mAh·g-1 after 100 cycles at 0.2C (1C corresponds to a current density of 1675 mA·g-1). It also gives a capacity of 485.3 mAh·g-1 at 2.0C in the rate capacity test.

Key words: Li/S battery, Composite, Rice husk, Miscanthus, Fir, Pomelo peel