The Effect of Gadolinium Ion Doping on Electronic Conductivity of LiFePO₄/C

Abstract:

In the recent years, LiFePO₄ has been widely developed as a cathode for lithium ion batteries because it has high theoretical capacity (170 mAh/g), good stability and is also environmentally friendly. However, the poor electronic conductivity (~10^-9 S/cm) and low diffusion coefficient of lithium ion (~10^-15-10^-14 cm²/s) are limiting its application. Some solutions to overcome this problem are carbon coating and doping metal ions. This study aims to determine the effect of Gd³⁺ ion doping on the electronic conductivity of LiFePO₄/C. The synthesis method was used is carbothermal reduction with Fe₂O₃, Gd₂O₃, LiH₂PO₄ and carbon black reagents. The synthesized LiFe_1-xGd_xPO₄/C was characterized using XRD, SEM-EDS, and four point probes. The results obtained showed that gadolinium ion doping increased the conductivity of LiFePO₄/C from 1.8952 x10^-6 to 8.69x10^-6 Scm^-1 using 0.07 mol ion Gd³⁺.

• Periodical: Key Engineering Materials (Volume 860)
• Pages: 69-74
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.860.69
• Online since: August 2020
• Authors: Iman Rahayu*, Engela Evy Ernawati, Atiek Rostika Noviyanti, Yusra Linda, Diana Rakhmawaty, Anggi Suprabawati, Anni Anggraeni, Husein Hernandi Bahti, Sahrul Hidayat
• Keywords: Conductivity, Doping, Gadolinium, LiFePO₄

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