Active Materials LiFeSi_xP_1-xO₄/C as Lithium Ion Battery Cathode with Doping Variations Si Ions (0≤x≤0,06)

Abstract

A cathode Lithium Ferro Phospate (LFP) composite material with variation doping ion Silicon (Si) with x = 0; 0,01; 0,03; 0.06 and carbon coating (LiFeSixP1-xO4/C) as lithium ion battery cathode were synthesized by a solid state reaction and wet milling methods. X-Ray Diffraction (XRD) pattern showed that the of olivine phase formed, and analysis characterization of Scanning Electron Microscopy (SEM) have shown average dimension particle of cathode in orde 1 micron. Analysis by Cyclic Voltammetry (CV) doping ion Si x = 0,03 have the best reversible electrochemical process than the other concentration, and have the highest charge and discharge capacity (78,745 mAh/g).

Oxidation State analysis of LiFeSixP1-xO4/C (x = 0.06) with X-ray Absorption Near Edge Structure (XANES) in Fe K-edge and Si K-edge

“…x O 4 /C possibly affect the Li + ion transport in cathode material (Zainuri et al, 2020). Furthermore, charge/discharge measurement also showed the enhancement of spesific capacity with increasing of Si composition (Zhao et al, 2017).…”

“…Carboration process carried out at 450 0 C for 2 hours under nitrogen atmosphere to form LFP Si-6% powder. The detail information of stoichiometric material and detail synthesis process can be referred in (Zainuri et al, 2020).…”

“…LiFePO4 material has been developed in many studies to investigate the electrochemical performance as a cathode material. Some techniques were used to improve the structural characteristic and electrochemical performance such as carbon coating, particle size reducing and atomic doping (Zainuri et al, 2020;Norouzi Banis et al, 2019;Chiang et.al., 2012;and Zhao et al, 2017). Atomic doping silicon in LiFeSixP1-…”

“…Carbon coating in LiFePO4 also showed that electrochemical performance has enhanced at initial charge/discharged capacities and efficiency. To investigate the structural characteristic of LiFePO4 material, some measurements have been used previously, for instance X-ray Diffraction characterization (Zainuri et al, 2020). But in some cases, especially in atomic doping material, XRD can not explain more detail about doping phenomenon.…”

“…XANES data in Fe K-edge also used linear combination fitting (LCF) to explain the composition of multivalent atom Fe 2+ /Fe 3+ . In addition, Transmisson Electron Microscopy (TEM) is also reported to complete the SEM analysis that was studied previously (Zainuri et al, 2020).…”