Electrochemical characteristics of phosphorus doped Si-C composite for anode active material of lithium secondary batteries
Transactions of Nonferrous Metals Society of China, 19 (4):
1018 - 1022 (2009)DOI: http://dx.doi.org/10.1016/S1003-6326(08)60399-4
Abstract
Phosphorus doped silicon-carbon composite particles were synthesized through a \DC\ arc plasma torch. Silane(SiH4) and methane(CH4) were introduced into the reaction chamber as the precursor of silicon and carbon, respectively. Phosphine(PH3) was used as a phosphorus dopant gas. Characterization of synthesized particles were carried out by scanning electron microscopy(SEM), X-ray diffractometry(XRD), X-ray photoelectron spectroscopy(XPS) and bulk resistivity measurement. Electrochemical properties were investigated by cyclic test and electrochemical voltage spectroscopy(EVS). In the experimental range, phosphorus doped silicon-carbon composite electrode exhibits enhanced cycle performance than intrinsic silicon and phosphorus doped silicon. It can be explained that incorporation of carbon into silicon acts as a buffer matrix and phosphorus doping plays an important role to enhance the conductivity of the electrode, which leads to the improvement of the cycle performance of the cell.
Description
Electrochemical characteristics of phosphorus doped Si-C composite for anode active material of lithium secondary batteries