Evaluation of Olivine LiFePO4 Polyanionic Cathode Material Using Density Functional Theory

• Published in: Key Engineering Materials
• Main Author: Shahrul Izwan A.; Fadhlul Wafi B.; Abqari Luthfi Albert A.; Muhd Zu Azhan Y.; Mohamad Fariz Mohamad T.; Oskar Hasdinor H.
• Format: Conference paper
• Language: English
• Published: Trans Tech Publications Ltd 2022
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85127272094&doi=10.4028%2fp-csw2yc&partnerID=40&md5=03be04989e334ad14bbd43454244d252

The first principles study on the LiFePO4 and FePO4 crystal has been evaluated using the density functional theory encrypted in the Cambridge Serial Total Energy Package (CASTEP) computer code. The structural properties, electronic properties, and intercalation voltage of the cathode material are presented. Without the Hubbard U parameter, the conventional functional of GGA-PBE and GGA-PBEsol unable to produce the experimental open-circuit voltage (OCV) and band gap (BG) of cathode material correctly. Generally, the value of the lattice parameter, OCV, and BG will increase as the U value is increased. For OCV, the suitable U value for the GGA-PBE and GGA-PBEsol is 3 eV, whereas, for BG, the appropriate U value for both functional is around 4.3 eV to 4.5 eV. Different Hubbard U value is needed for different functional. It is found that GGA-PBEsol + U is the best parameter to calculate the electrical properties of LiFePO4 material. © 2022 Trans Tech Publications Ltd, Switzerland.