Enhanced electrochemical performance of Li-rich layered cathode materials by surface modification with P2O5

• Published in: Electrochemistry communications Vol. 49; pp. 83 - 87
• Main Authors: Hou, Mengyan, Liu, Jinlong, Guo, Shaoshuai, Yang, Jun, Wang, Congxiao, Xia, Yongyao
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01-12-2014; Amsterdam Elsevier; New York, NY
• Subjects: Applied sciences; Cathode materials; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Exact sciences and technology; Li-rich layered oxides; Lithium-ion batteries; P2O5 heat-treatment; Surface modification; Lithium-ion batteries; Li-rich layered oxides; Surface modification; Cathode materials; P2O5 heat-treatment; Phosphorus oxide; Lithium ion batteries; Heat treatment; Fourier transformation; Gas solid reaction; heat-treatment; Lithium Oxides; X ray; Electrode material; Discharge charge cycle; Surface structure; O; Characterization; P; Lamellar structure; Phosphorus Oxides; Photoelectron spectrometry; Electrical characteristic; Cathode; Secondary cell; X ray diffraction; Surface treatment; Infrared spectrometry; Transmission electron microscopy; Morphology; Current efficiency; Manganese Oxides
• ISSN: 1388-2481; 1873-1902
• DOI: 10.1016/j.elecom.2014.10.009

Rate capability and charge/discharge coulombic efficiency of Li-rich layered oxides was greatly improved by surface modification with P2O5 through a gas–solid reaction. The P2O5 treatment results in forming a uniform nanoscale coating layer of ionically conductive Li3PO4 and spinel-like material on Li-rich layered oxide particles. The resulting material delivers a charge/discharge coulombic efficiency of 90% compared with 81% of the pristine sample during the first cycle. The treated electrode also exhibits improved rate capability with a reversible capacity of 148mAhg−1 at 4 C-rate vs. 269mAhg−1 at 0.1 C-rate between 2.0 and 4.8V.
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•A gas–solid reaction between P2O5 and Li-rich layered oxide was employed for surface modification.•A uniform and continuous coating layer presents on the surface of pristine material.•Remarkable improvement in charge/discharge efficiency and rate capability was obtained after surface modification.