Layered δ-MnO2 as positive electrode for lithium intercalation

Authors

Guodong Du, University of WollongongFollow
Jieqiang Wang, University of Jinan, China
Zaiping Guo, University of WollongongFollow
Zhixin Chen, University of WollongongFollow
Hua-Kun Liu, University of WollongongFollow

RIS ID

37548

Publication Details

Du, G., Wang, J., Guo, Z., Chen, Z. & Liu, H. (2011). Layered δ-MnO2 as positive electrode for lithium intercalation. Materials Letters, 65 (9), 1319-1322.

Abstract

Layer structured δ-MnO₂ was synthesized by a microwave-assisted hydrothermal method. The morphology of the product consists of flower-like spheres that range from about 200 nm to 3 μm in diameter and are composed of sheets about 5–10 nm in thickness. When tested in the voltage range of 2 to 4.5 V vs. Li⁺/Li in coin cells, the separator is blocked, handicapping Li⁺ conductivity and leading to cell failure. When tested in the voltage range of 2 to 4 V in ethylene carbonate/dimethyl carbonate (EC/DMC), the δ-MnO₂ delivers an initial reversible capacity of 143.7 mAh g⁻¹ and can maintain 120 mAh g⁻¹ at the 60th cycle. The δ-MnO₂ electrode shows good cycling stability at different current densities and delivers a discharge capacity of about 90 mAh g⁻¹ at 1 C, indicating that it is a promising cathode material for lithium ion batteries.