Electrochemical characteristics of phosphorus doped silicon and graphite composite for the anode materials of lithium secondary batteries

Myung Ho Kong, Jae Hyun Noh, Dong Jin Byun, Joong Kee Lee

Research output: Contribution to journalArticle

19 Citations (Scopus)

Abstract

Poly-crystalline silicon particles with a diameter of 80∼100 nm were synthesized by the plasma arc discharge method. Natural graphite, poly-crystalline silicon, poly-crystalline silicon/graphite composite and phosphorus doped poly-crystalline silicon/graphite composite particles were used as the anode materials of lithium secondary batteries and their electrochemical performances were compared. The phosphorus component on the surface and internal structure of the silicon particles were observed by XPS and SIMS analyses, respectively. In our experiments, the phosphorus doped silicon/graphite composite electrode exhibited better cycle performance than the intrinsic silicon/graphite composite electrode. The discharge capacity retention efficiency of the intrinsic silicon/graphite composite and phosphorus doped silicon/graphite composite electrodes after 20 cycles were 8.5% and 75%, respectively. The doping of phosphorus leads to an increase in the electrical conductivity of silicon, which plays an important role in enhancing the cycle performance. The incorporation of silicon into graphite has a synergetic effect on the mitigation of the volume change and conducting medium in the composite electrode during the charge-discharge reaction.

Original languageEnglish
Pages (from-to)376-381
Number of pages6
JournalJournal of Electroceramics
Volume23
Issue number2-4
DOIs
Publication statusPublished - 2009 Oct 1

    Fingerprint

Keywords

  • Anode
  • Composite
  • Lithium secondary battery
  • Phosphorus doping
  • Silicon

ASJC Scopus subject areas

  • Ceramics and Composites
  • Electronic, Optical and Magnetic Materials
  • Materials Chemistry
  • Condensed Matter Physics
  • Electrical and Electronic Engineering
  • Mechanics of Materials

Cite this