Kai Feng
Dalian Institute of Chemical Physics, China
Title: Improving the electrochemical performances of Li3V2 (PO4)3 and LiTi2 (PO4)3 by ion doping
Biography
Biography: Kai Feng
Abstract
Li3V2 (PO4)3 (LVP) is a potential cathode for advanced lithium ion batteries. However, its electrochemical performance is limited by the poor electronic conductivity. Ion doping is an effective method for improving electronic conductivity. Ion doping at different sites were explored. Bi doped and B doped LVP were synthesized via a sol-gel method. All the samples remain the crystal structure of LVP. Li3V2 (P0.97B0.03O4)3/C and Li3V1.97Bi0.03 (PO4)3/C deliver excellent electrochemical performances, such as specific capacity, stability and rate performances. The excellent electrochemical performance can be attributed to its larger Li ion diffusion, smaller particle size, higher structural stability and electronic conductivity induced by ion doping. LiTi2 (PO4)3 (LTP) is a candidate anode for aqueous lithium ion batteries. Its electrochemical performance is also limited by its low electronic conductivity. The first anion ion doped LTP was studied here. We successfully synthesized a series of F-doped LiTi2 (PO4)3-xFx(x=0, 0.06, 0.12, 0.18) /C nanoparticles samples by sol-gel method. F doping improves the discharge voltage platform and structure stability, reduces the particle size and band gap. As a result, the rate and cycle stability are enhanced obviously.