Self-supported nickel-coated NiO arrays for lithium-ion batteries with enhanced capacity and rate capability

• Published in: Electrochimica acta Vol. 67; pp. 73 - 78
• Main Authors: Mai, Y.J., Xia, X.H., Chen, R., Gu, C.D., Wang, X.L., Tu, J.P.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 15-04-2012; Elsevier
• Subjects: Applied sciences; Arrays; Deposition; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Electrodes; Electronic conductivity; Electronics; Exact sciences and technology; Flakes; Lithium-ion batteries; Magnetron sputtering; Nanoparticles; Nickel; Nickel nanoparticle; Nickel oxide; Sputtering; Voltage hysteresis; Magnetron sputtering; Electronic conductivity; Voltage hysteresis; Nickel oxide; Nickel nanoparticle; Nanoparticle; Nickel Oxides; Discharge charge cycle; Surface structure; Electrodes; Physical vapor deposition; Hysteresis; Electrical characteristic; Modified material; Scanning electron microscopy; Cycling; Transition metal; Secondary cell; X ray diffraction; Transmission electron microscopy; Morphology; Lithion ion batteries; Nickel; Specific capacity; Plasma deposition; Electrochemical impedance spectroscopy
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2012.02.013

Self-supported nickel-coated NiO arrays are prepared by chemical bath deposition of NiO flake arrays followed by magnetron sputtering of nickel nanoparticles. The effect of sputtering time, namely, coverage of nickel nanoparticles, on the lithium storage performance of Ni-coated NiO array electrode is investigated. It is found that the optimum sputtering time is 60s, and such electrode delivers a reversible capacity of 455, 316 and 187mAhg−1 at a current density of 2, 4 and 7.18Ag−1, respectively, higher than the bare NiO array electrode. The deposited nickel nanoparticles keep the NiO active particles electrically connected and thus improve the electronic conductivity, and also stabilize the flake microstructure during cycling, resulting in the increase in reversible capacity and rate capability. The Ni-coated NiO array electrode, however, is still suffered from a large voltage hysteresis, indicating that the enhanced electronic conductivity is not effective on decreasing this hysteresis.