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1.
The Si/MgO/graphite composite was synthesized by high energy ball-milling and evaluated as a durable anode for lithium-ion batteries. EDX mapping indicated that Si was dispersed homogeneously in the MgO matrix. The composite delivered an initial capacity of ~ 700 mAh/g and maintained a capacity of 630 mAh/g after 74 cycles at 0.5 mA/cm2; even at 8 mA/cm2 it delivered more than 85% of its capacity. Its volumetric capacity is double that of carbon. The coulombic efficiency climbed from 77% in the first cycle to above 99.5% after 20 cycles, and retained that value.  相似文献   

2.
We report the electrochemical performance of carbon-coated TiO2 nanobarbed fibers (TiO2@C NBFs) as anode material for lithium-ion batteries. The TiO2@C NBFs are composed of TiO2 nanorods grown on TiO2 nanofibers as a core, coated with a carbon shell. These nanostructures form a conductive network showing high capacity and C-rate performance due to fast lithium-ion diffusion and effective electron transfer. The TiO2@C NBFs show a specific reversible capacity of approximately 170 mAh g 1 after 200 cycles at a 0.5 A g 1 current density, and exhibit a discharge rate capability of 4 A g 1 while retaining a capacity of about 70 mAh g 1. The uniformly coated amorphous carbon layer plays an important role to improve the electrical conductivity during the lithiation–delithiation process.  相似文献   

3.
Integrated analysis of the cycling parameters (reversible specific capacity, Coulomb efficiency, irreversible loss of cycle capacity, accumulated irreversible capacity, and retention of reversible capacity) of synthetic graphite of MAG brand as an active material for the negative electrode of lithium-ion batteries was made.  相似文献   

4.
In the present work,an interconnected sandwich carbon/Si-SiO2/carbon nanospheres composite was prepared by template method and carbon thermal vapor deposition(TVD).The carbon conductive layer can not only efficiently improve the electronic conductivity of Si-based anode,but also play a key role in alleviating the negative effect from huge volume expansion over discharge/charge of Si-based anode.The resulting material delivered a reversible capacity of 1094 mAh/g,and exhibited excellent cycling stability.It kept a reversible capacity of 1050 mAh/g over 200 cycles with a capacity retention of 96%.  相似文献   

5.
In the present work,an interconnected sandwich carbon/Si-SiO_2/carbon nanospheres composite was prepared by template method and carbon thermal vapor deposition(TVD).The carbon conductive layer can not only efficiently improve the electronic conductivity of Si-based anode,but also play a key role in alleviating the negative effect from huge volume expansion over discharge/charge of Si-based anode.The resulting material delivered a reversible capacity of 1094 mAh/g,and exhibited excellent cycling stability.It kept a reversible capacity of 1050 mAh/g over 200 cycles with a capacity retention of 96%.  相似文献   

6.
Zhou  Jiahui  Jiang  Feng  Li  Sijie  Xu  Zhijie  Sun  Wei  Ji  Xiaobo  Yang  Yue 《Journal of Solid State Electrochemistry》2019,23(7):1991-2000
Journal of Solid State Electrochemistry - Considering serious pollution from the traditional chemical synthesis process, the resource-rich, clean electrode materials are greatly desired....  相似文献   

7.
Journal of Solid State Electrochemistry - Exploring the fast-charge anodes is crucial to meet the needs of lithium-ion battery (LIB) markets. Here, a hollow hexagonal mesoporous TiO2/carbon...  相似文献   

8.
Graphene nanosheets (GNSs) were prepared from artificial graphite by oxidation, rapid expansion and ultrasonic treatment. The morphology, structure and electrochemical performance of GNSs as anode material for lithium-ion batteries were systematically investigated by high-resolution transmission electron microscope, scanning electron microscope, X-ray diffraction, Fourier transform infrared spectroscopy and a variety of electrochemical testing techniques. It was found that GNSs exhibited a relatively high reversible capacity of 672 mA h/g and fine cycle performance. The exchange current density of GNSs increased with the growth of cycle numbers exhibiting the peculiar electrochemical performance.  相似文献   

9.
A sandwiched SiC@Pb@C nanocomposite was prepared through a simple ball-milling route and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. The SiC@Pb@C nanocomposite exhibits a much improved reversible capacity and cycling life as compared with a bare Pb anode. A reversible volumetric capacity of >1,586 mAh cm−3 (207 mAh g−1) can be maintained after 600 cycles of charge and discharge in the potential interval between 0.005 and 1.0 V, which far exceeds those reported previously in the literature. The enhanced electrochemical performance is ascribed to the sandwiched structure in which nanosized Pb particles were anchored in between the rigid SiC core and the outer carbon shell, mitigating the damage done by the large volume change of the Pb interlayer during the alloying/dealloying process.  相似文献   

10.
Silicon monoxide/graphite/multi-walled carbon nanotubes (SiO/G/CNTs) material was prepared by ball milling followed by chemical vapor deposition method and characterized by X-ray diffraction, scanning electron microscopy (SEM), galvanostatic charge–discharge, and AC impedance spectroscopy, respectively. The results revealed that SiO/G/CNTs exhibited an initial specific discharge capacity of 790 mAh g−1 with a columbic efficiency of 65%. After 100 cycles, a high reversible capacity of 495 mAh g−1 is still retained. The improved electrochemical properties were due to beneficial SEI by the SEM and EIS results.  相似文献   

11.
We have developed a Si/graphene oxide electrode synthesized via ultrasonication-stirring method under alkaline condition. Scanning electron microscopy(SEM), transmission electron microscope(TEM), EDS dot-mapping and high-resolution transmission electron microscopy(HRTEM) results show that Si particles are evenly dispersed on the graphene oxide sheets. The electrochemical performance was investigated by galvanostatic charge/discharge tests at room temperature. The results revealed that Si/graphene oxide electrode exhibited a high reversible capacity of 2825 mAh/g with a coulombic efficiency of 94.6%at 100 mA/g after 15 cycles and a capacity retention of 70.8% after 105 cycles at 4000 mA/g. These performance parameters show a great potential in the high-performance batteries application for portable electronics, electric vehicles and renewable energy storage.  相似文献   

12.
Tin oxide (SnO2)/graphene composite was synthesized from SnCl2?·?2H2O and graphene oxide (GO) by a wet chemical-hydrothermal route. The GO was reduced to graphene nanosheet (GNS) and flower-like SnO2 nano-crystals with size about 40 nm were homogeneously distributed on the surface of GNS. The SnO2/graphene composites delivered a superior first discharge capacity of 1941.9 mAhg?1 with a reversible capacity of 901.7 mAhg?1 at the current density of 100 mAg?1. Moreover, even at higher densities of 200 and 500 mAg?1, the SnO2/graphene composite still maintained enhanced cycling stability. After 40 cycles, the discharge capacity was still maintained at 691.1 mAhg?1 at the current density of 100 mAg?1. The SnO2/graphene composite displayed an outstanding Li-battery performance with large reversible capacity and enhanced rate performance, which can be attributed to the highly uniform distribution of SnO2 nanoparticles and high reduction degree of graphene. This result strongly indicates that the SnO2/graphene composite was a promising anode material in high-performance lithium-ion batteries.  相似文献   

13.
Journal of Solid State Electrochemistry - We demonstrate here that mesoporous tin dioxide (abbreviated M-SnO2) with a broad pore size distribution can be a prospective anode in lithium-ion...  相似文献   

14.
Ba  Chaoqun  Shi  Liyi  Wang  Zhuyi  Chen  Guorong  Wang  Shuai  Zhao  Yin  Zhang  Meihong  Yuan  Shuai 《Research on Chemical Intermediates》2017,43(10):5857-5869
Research on Chemical Intermediates - The electrochemical performance of lithium-ion batteries are affected by the anode materials. SnO2 is an important anode material due to its high theoretical...  相似文献   

15.
A novel anode material for lithium-ion batteries, tin nanoparticles coated with carbon embedded in graphene (Sn@C/graphene), was fabricated by hydrothermal synthesis and subsequent annealing. The structure and morphology of the nanocomposite were characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The size of the Sn@C nanoparticles is about 50-200 nm. The reversible specific capacity of the nanocomposite is ∼662 mAh g−1 at a specific current of 100 mA g−1 after 100 cycles, even ∼417 mAh g−1 at the high current of 1000 mA g−1. These results indicate that Sn@C/graphene possesses superior cycle performance and high rate capability. The enhanced electrochemical performances can be ascribed to the characteristic structure of the nanocomposite with both of the graphene and carbon shells, which buffer the volume change of the metallic tin and prevent the detachment and agglomeration of pulverized tin.  相似文献   

16.
Wen  Yunping  Liu  Yao  Bin  Duan  Wang  Zhuo  Wang  Congxiao  Cao  Yuliang  Ai  Xinping  Xia  Yongyao 《中国科学:化学(英文版)》2019,62(1):118-125
This work developed a facile way to mass-produce a carbon-coated TiP_2O_7 nanoporous microsphere(TPO-NMS) as anode material for aqueous lithium-ion batteries via solid-phase synthesis combined with spray drying method. TiP_2O_7 shows great prospect as anode for aqueous rechargeable lithium-ion batteries(ALIBs) in view of its appropriate intercalation potential of-0.6 V(vs. SCE) before hydrogen evolution in aqueous electrolytes. The resulting sample presents the morphology of secondary microspheres(ca. 20 μm) aggregated by carbon-coated primary nanoparticles(100 nm), in which the primary nanoparticles with uniform carbon coating and sophisticated pore structure greatly improve its electrochemical performance. Consequently, TPONMS delivers a reversible capacity of 90 mA h/g at 0.1 A/g, and displays enhanced rate performance and good cycling stability with capacity retention of 90% after 500 cycles at 0.2 A/g. A full cell containing TPO-NMS anode and LiMn_2O_4 cathode delivers a specific energy density of 63 W h/kg calculated on the total mass of anode and cathode. It also shows good rate capacity with56% capacity maintained at 10 A/g rate(vs. 0.1 A/g), as well as long cycle life with the capacity retention of 82% after 1000 cycles at 0.5 A/g.  相似文献   

17.
18.
The pristine CeVO4 and CeVO4/CNT hybrid composite nanostructured samples were facilely synthesized using a simple silicone oil-bath method.From the X-ray diffra...  相似文献   

19.
A facile synthesis of Sn O2/corncob-derived activated carbon(CAC) composite was proposed,and the CAC used here has high specific surface area(over 3000 m2/g) and ample oxygen-containing functional groups.The microstructures and morphology as well as electrochemical performance of the Sn O2/CAC composites were investigated by X-ray diffraction,scanning electron microscopy,transmission electron microscopy and relevant electrochemical characterization. The results show that the mass ratios of Sn O2 to CAC have a significant effect on the structures and properties of the composites. The sample with 34% Sn O2 delivered a capacity of 879.8 m Ah/g in the first reversible cycle and maintained at 634.0 m Ah/g(72.1% retention of the initial reversible capacity) after 100 cycles at a current density of 200 m A/g. After 60 cycles at different specific currents from 200 to 2000 m A/g,the reversible specific capacity was still maintained at 632.8 m Ah/g at a current density of 200 m A/g. These results indicate that SnO 2/CAC can be a desirable alternative anode material for lithium ion batteries.  相似文献   

20.
Iron sulfide-embedded carbon microspheres were prepared via a solvothermal process and show high specific capacity and excellent high-rate performance as anode material for lithium-ion batteries.  相似文献   

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