Co-reporter:Zheng Ma, Jichun Huang, Jingbin Quan, Lin Mei, Jun Guo and Decheng Li
RSC Advances 2016 vol. 6(Issue 25) pp:20522-20531
Publication Date(Web):15 Feb 2016
DOI:10.1039/C5RA22330J
A series of layered lithium-rich oxides 0.6Li[Li1/3Mn2/3(1−x)Zr2/3x]O2·0.4LiMn5/12Ni5/12Co1/6O2 (0 ≤ x ≤ 10%) have been prepared by a spray-dry method. The crystal structural and morphological properties of all the samples have been studied by XRD, XPS, SEM, HRTEM and SAED. XRD results reveal Zr4+ ions are doped into the lattice. HRTEM results suggest Zr4+ ions can stabilize the layered structural feature during cycles. The electrochemical properties are remarkably upgraded by Zr4+ ion doping. The discharge capacity of Zr4% doped samples remains 218.9 mA h g−1 after 100 cycles with a capacity retention of 84% at 20 mA g−1 between 2.0 and 4.8 V, while the undoped samples drop to 168.6 mA h g−1 with a capacity retention of 72%. Moreover, Zr4% doped samples show the lowest voltage decay, about 0.16 V lower than the undoped samples after 100 cycles. This study suggests suitable Zr4+ doping can improve the electrochemical performances and suppress voltage decay for layered lithium-rich oxides.
Co-reporter:Jingbin Quan, Lin Mei, Zheng Ma, Jichun Huang and Decheng Li
RSC Advances 2016 vol. 6(Issue 61) pp:55786-55791
Publication Date(Web):31 May 2016
DOI:10.1039/C6RA08308K
Copper manganese oxide Cu1.5Mn1.5O4, a novel anode material for lithium-ion batteries, was synthesized via a spray drying method. SEM images demonstrated a strong dependence of the morphologies of secondary and primary particles on the synthesis parameters. The surface electronic states and chemical compositions of manganese and copper in the sample were confirmed by XPS. The electrochemical results demonstrated that the sample synthesized at an annealing temperature of 700 °C showed great cycling performance, and retained a specific capacity of 464 mA h g−1 at a current of 100 mA g−1 after 60 cycles.
Co-reporter:Hongdan Sun, Bingbo Xia, Weiwei Liu, Guoqing Fang, Jingjing Wu, Haibo Wang, Ruixue Zhang, Shingo Kaneko, Junwei Zheng, Hongyu Wang, Decheng Li
Applied Surface Science 2015 Volume 331() pp:309-314
Publication Date(Web):15 March 2015
DOI:10.1016/j.apsusc.2015.01.120
Highlights
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Al-doped ZnO (AZO)-coated LiNi0.5Mn1.5O4 (LNMO) was prepared by a traditional sol–gel method.
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Al-doped ZnO (AZO) layer grown on the surface of LNMO is high ordered.
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At a high rate of 10 C, the discharge capacity of the AZO-coated LNMO electrode can reach 114 mAh g−1.
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Al-doped ZnO (AZO) modification improved cyclic performance of LNMO at high temperatures.
Co-reporter:Fuqiang Fan, Guoqing Fang, Ruixue Zhang, Yanhui Xu, Junwei Zheng, Decheng Li
Applied Surface Science 2014 Volume 311() pp:484-489
Publication Date(Web):30 August 2014
DOI:10.1016/j.apsusc.2014.05.094
Highlights
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The thickness of carbon coating layers can be successfully controlled through varying molar concentration of aqueous glucose solution.
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Coating carbon thickness and carbon content are two important factors on the electrochemical performances of CoSnO3@C.
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CoSnO3@C under optimized conditions exhibits the optimal balance between the volume buffering effect and reversible capacity.
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As-prepared CoSnO3@C under optimized conditions shows excellent electrochemical performances, whose reversible capacity could reach 491 mA h g−1 after 100 cycles.
Co-reporter:Ruixue Zhang, Guoqing Fang, Weiwei Liu, Bingbo Xia, Hongdan Sun, Junwei Zheng, Decheng Li
Applied Surface Science 2014 Volume 292() pp:682-687
Publication Date(Web):15 February 2014
DOI:10.1016/j.apsusc.2013.12.033
Highlights
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Carbon coated Mn–Sn complex metal oxide composite (MTO@C) was used as anode material in Li-ion battery for the first time.
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Core-shell MTO@C composite had been successfully prepared via a simple glucose hydrothermal reaction and subsequent carbonization approach.
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Compared with bare MnSnO3 and MTO samples, the MTO@C composite exhibited superior cyclic performance delivering a reversible capacity of 409 mA h g−1 even after 200 cycles.
Co-reporter:Guoqing Fang, Shingo Kaneko, Weiwei Liu, Bingbo Xia, Hongdan Sun, Ruixue Zhang, Junwei Zheng, Decheng Li
Electrochimica Acta 2013 Volume 111() pp:627-634
Publication Date(Web):30 November 2013
DOI:10.1016/j.electacta.2013.08.096
Development of high-capacity anode materials equipped with strong cyclestability is a great challenge for use as practical electrode for high-performance lithium-ion rechargeable battery. In this study, we synthesized a carbon coated Zn–Sn metal nanocomposite oxide and carbon spheres (ZTO@C/CSs) via a simple glucose hydrothermal reaction and subsequent carbonization approach. The carbon coated ZTO/carbon microspheres composite maintained a reversible capacity of 680 mAh g−1 after 345 cycles at a current density of 100 mA g−1, and furthermore the cell based on the composite exhibited an excellent rate capability of 470 mAh g−1 even when the cell was cycled at 2000 mA g–1. The thick carbon layer formed on the ZTO nanoparticles and carbon spheres effectively buffered the volumetric change of the particles, which thus prolonged the cycling performance of the electrodes.
Co-reporter:Weiwei Liu, Guoqing Fang, Bingbo Xia, Hongdan Sun, Shingo Kaneko and Decheng Li
RSC Advances 2013 vol. 3(Issue 36) pp:15630-15635
Publication Date(Web):27 Jun 2013
DOI:10.1039/C3RA41653D
To improve the rate capability of lithium-rich layered cathode material Li[Li0.2Ni0.17Mn0.56Co0.07]O2 a facile method aimed at micro-structural rearrangement was proposed. Through the combination of excess lithium and chemical activation post-treatment, the resulting material showed well ordered bulk and surface structures. The capacity retention for the modified material improved significantly (compared with untreated sample) at high discharge current densities. Moreover, the unique electrochemical behavior of the modified material reveals the existence of the chemically activated Li2MnO3 component within the composite.
Co-reporter:Guoqing Fang;Weiwei Liu;Shingo Kaneko
Journal of Solid State Electrochemistry 2013 Volume 17( Issue 9) pp:2521-2529
Publication Date(Web):2013 September
DOI:10.1007/s10008-013-2137-9
Sn-Co-C alloy as a promising anode material was prepared via a facile carbothermal reduction method, using both graphite and sucrose as the composited carbon sources. The effect of the combination pattern of graphite and sucrose on the microstructure and electrochemical performances of the alloys was investigated using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and galvanostatic cycling tests. Compared with the Sn-Co-C samples using only graphite or sucrose as the carbon sources, the sample using the composited carbon sources has a relative higher reversible capacity and better rate capability, which is probably related to the continuous and stable conductive network formed by graphite and amorphous carbon originated from the thermal decomposition of sucrose, as well as the small particle size and uniform distribution in the conductive network.
Co-reporter:Bing Liu, Qian Zhang, Shici He, Yuichi Sato, Junwei Zheng, Decheng Li
Electrochimica Acta 2011 Volume 56(Issue 19) pp:6748-6751
Publication Date(Web):30 July 2011
DOI:10.1016/j.electacta.2011.05.071
Lithium-rich nickel–manganese–cobalt oxide, Li1.2Ni0.18Mn0.59Co0.03O2, prepared by spray-dry process, exhibits rapid capacity fade and poor rate capability. The surface of Li1.2Ni0.18Mn0.59Co0.03O2 can be modified with LiCoPO4 through co-precipitation method in order to improve its electrochemical properties. The resultant LiCoPO4 particles are in nano-scale and accumulate on the surface of the Li1.2Ni0.18Mn0.59Co0.03O2 particles. The surface modification by LiCoPO4 is shown to significantly improve both the cyclic performance and the rate capability of Li1.2Ni0.18Mn0.59Co0.03O2.Highlights► Li[Li0.2Ni0.18Mn0.59Co0.03]O2 was prepared by Spray dry method. ► Li[Li0.2Ni0.18Mn0.59Co0.03]O2 was modified with LiCoPO4 by Co-precipitation. ► LiCoPO4 particles are about 20 nm and could not form a uniform thin layer. ► LiCoPO4 modification upgrades the cycleability of Li[Li0.2Ni0.18Mn0.59Co0.03]O2. ► LiCoPO4 modification improves the rate capability of Li[Li0.2Ni0.18Mn0.59Co0.03]O2.
