39 results on '"Gu, C.D."'
Search Results
2. Non-aqueous electrodeposition of porous tin-based film as an anode for lithium-ion battery
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Gu, C.D., Mai, Y.J., Zhou, J.P., You, Y.H., and Tu, J.P.
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ELECTROPLATING , *POROUS materials , *THIN films , *LITHIUM-ion batteries , *METAL foils , *CHOLINE chloride , *ETHYLENE glycol , *MOLECULAR self-assembly - Abstract
Abstract: Porous tin-based films are electrodeposited on copper foils from a choline chloride/ethylene glycol based electrolyte containing SnCl2·2H2O without any complexing agent or additive. Increasing the deposition time and voltage produces thicker films. The initially deposited Sn grains are relatively uniform with an average size of 200–300 nm and a kind of self-assembly distribution constructing an open and bicontinuous porous network. The architecture of these films possesses a double-layer structure, i.e. SnO2 (superficial layer)/Sn–Cu alloy (bottom layer), which is revealed by X-ray diffractometer and X-ray photoelectron spectroscopy. The electrochemical performance of the porous tin-based films as anode for lithium-ion batteries is measured. Although the capacity fades gradually with repeated cycling, a reversible capacity of 300-350 mAh g−1 is maintained for more than 50 cycles, which suggests that the in situ formed Sn--Cu alloy could provide an interlocking interface between active materials and current collector. Therefore, the tin''s shedding from the current collector can be restrained. Moreover, the inactive materials, such as the oxide in the superficial layer and the Cu in the bottom layer, could also act as buffers to relieve the induced volume expansion of Sn during the repeated lithiathion/delithiation process, thus giving the good cycle performances. [Copyright &y& Elsevier]
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- 2012
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3. Graphene anchored with nickel nanoparticles as a high-performance anode material for lithium ion batteries
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Mai, Y.J., Tu, J.P., Gu, C.D., and Wang, X.L.
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GRAPHENE , *METAL nanoparticles , *NICKEL , *ANODES , *LITHIUM-ion batteries , *SURFACE chemistry , *SUPERIONIC conductors - Abstract
Abstract: The surface of graphene is modified by nickel nanoparticles which are in-situ reduced from NiO nanoparticles by graphene. The nickel nanoparticles obtained are up to 10nm in size and are strongly anchored on the surface of graphene sheets. As an anode material for lithium ion batteries, the graphene–Ni hybrid material delivers a reversible capacity of 675mAhg−1 after 35 discharge/charge cycles at a current density of 100mAg−1, corresponding to 85% retention of the initial charge capacity. In addition, the graphene–Ni hybrid electrode exhibits much better rate capability compared to its pure counterpart operated at various rates between 200 and 800mAg−1. Such enhanced lithium storage performance of the graphene–Ni hybrid electrode can be ascribed to the enhanced electronic transport and Li+ migration through the solid electrolyte interphase (SEI) film as a consequence of that the anchored nickel nanoparticles increase the electronic conductivity and modify the structure of SEI film covering the surface of graphene. [Copyright &y& Elsevier]
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- 2012
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4. A preeminent gel blending polymer electrolyte of poly(vinylidene fluoride-hexafluoropropylene) -poly(propylene carbonate) for solid-state lithium ion batteries.
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Liang, Y.F., Xia, Y., Zhang, S.Z., Wang, X.L., Xia, X.H., Gu, C.D., Wu, J.B., and Tu, J.P.
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FLUOROETHYLENE , *PROPYLENE carbonate , *POLYELECTROLYTES , *POLYMER blends , *LITHIUM-ion batteries , *POLYMER colloids - Abstract
Abstract A compositive synthesis of gel polymer electrolytes by blending poly(propylene carbonate) (PPC) into poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) as a polymer host is proposed. The blending polymer is produced by a facile solution casting method and ester groups of PPC are successful introduced into PVDF-HFP. The gel polymer electrolyte displays an excellent ion conductivity of 1.18 × 10−3 S cm−1, broad electrochemical window up to 4.8 V (vs. Li/Li+) and outstanding electrochemical stability within rechargeable lithium batteries at room temperature. The improvement of ion conductivity is attributed to the decrease of polymer crystallizability and the increase of micro pores. The strategy of blending is promising for the modification of PVDF-HFP electrolyte and foreground application in next-generation solid energy conversion devices. [ABSTRACT FROM AUTHOR]
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- 2019
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5. A superior composite gel polymer electrolyte of Li7La3Zr2O12- poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) for rechargeable solid-state lithium ion batteries.
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Liang, Y.F., Deng, S.J., Xia, Y., Wang, X.L., Xia, X.H., Wu, J.B., Gu, C.D., and Tu, J.P.
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LITHIUM-ion batteries , *COMPOSITE materials , *POLYMER electrodes , *LITHIUM compounds , *POLYVINYLIDENE fluoride , *PROPENE - Abstract
High-quality solid electrolyte is essential for the growing need of lithium ion batteries. Herein, we report a novel organic-inorganic composite electrolyte based on Li 7 La 3 Zr 2 O 12 ceramic powder incorporated into PVDF-HFP through a simple combined method. At room temperature, the composite polymer electrolyte (CPE) possesses a good ionic transmission improvement of 3.71 × 10 −4 S cm −1 . The CPE behaves a fine lithium ion transference number of 0.58 and an electrochemical window of up to 4.65 V. CPEs display meliorative electrochemical stability compared to pure PVDF-HFP electrolyte. The cathode presents an excellent initial discharge capacity of 163.1 mAh g −1 at 0.2 C in Li/CPE/LiFePO 4 cell. The cell with CPE displays much better capacity retention than that with pure PVDF-HFP electrolyte. The Li 7 La 3 Zr 2 O 12 modified PVDF-HFP is a promising electrolyte for lithium ion batteries. [ABSTRACT FROM AUTHOR]
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- 2018
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6. Recent development in lithium metal anodes of liquid-state rechargeable batteries.
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Liu, S.F., Wang, X.L., Xie, D., Xia, X.H., Gu, C.D., Wu, J.B., and Tu, J.P.
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LITHIUM-ion batteries , *ANODES , *STORAGE batteries , *ENERGY density , *ELECTROCHEMISTRY , *DENDRITIC crystals - Abstract
Lithium metal has always been considered as a “Holy Grail” of anode materials for high-energy-density batteries owing to its extremely high theoretical gravimetric capacity of 3860 mAh g −1 and the lowest electrochemical potential of −3.04 V. Unfortunately, huge challenges including unlimited dendrite growth and complex interfacial reaction accompanied with relatively low Coulombic efficiency have extremely restricted its practical applications for decades. In this review, we discuss recently exciting achievements in modifying Li metal anodes, particularly regarding porous structure design, surface modification, heterogeneous seed strategy, potential substitutes including Li powder, and pre-lithiated composite. Although each improvement method has its own advantage, we believe appropriate combination of them will yield more promising results. Finally, we discuss core issues and potential opportunities of Li metal anode, expecting to shed new light on future research in this field. [ABSTRACT FROM AUTHOR]
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- 2018
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7. Preparation of Li7P3S11 glass-ceramic electrolyte by dissolution-evaporation method for all-solid-state lithium ion batteries.
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Xu, R.C., Xia, X.H., Yao, Z.J., Wang, X.L., Gu, C.D., and Tu, J.P.
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GLASS-ceramics synthesis , *EVAPORATION (Chemistry) , *DISSOLUTION (Chemistry) , *ELECTROLYTES , *LITHIUM-ion batteries , *IONIC conductivity - Abstract
Design/fabrication of solid state electrolytes with high ionic conductivity is of great importance to develop next-generation Li ion batteries. In this work, the Li 7 P 3 S 11 glass-ceramic electrolyte is successfully synthesized by dissolution- evaporation approach. The solvent effect on the electrochemical performance of Li 7 P 3 S 11 is investigated by electrochemical impedance spectroscopy and chronoamperometry tests. The Li 7 P 3 S 11 electrolyte prepared by a solution of acetonitrile has a high ionic conductivity of 9.7 × 10 −4 S cm −1 at 298 K and a low activation energy of 31.2 kJ mol −1 . Impressively, a wide and stable electrochemical window up to 5 V (vs. Li/Li + ) is demonstrated between the solid electrolyte and lithium electrode. The developed dissolution-evaporation approach shows good industrial prospect due to its advantages of energy conservation and high efficiency. [ABSTRACT FROM AUTHOR]
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- 2016
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8. Integrated 3D porous C-MoS2/nitrogen-doped graphene electrode for high capacity and prolonged stability lithium storage.
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Xie, D., Tang, W.J., Xia, X.H., Wang, D.H., Zhou, D., Shi, F., Wang, X.L., Gu, C.D., and Tu, J.P.
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LITHIUM-ion batteries , *LITHIUM , *GRAPHENE , *NITROGEN , *X-ray photoelectron spectroscopy , *TRANSMISSION electron microscopy , *ELECTRODES - Abstract
Scrupulous design and fabrication of advanced anode materials are of great importance for developing high-performance lithium ion batteries. Herein, we report a facile strategy for construction of free-standing and free-binder 3D porous carbon coated MoS 2 /nitrogen-doped graphene (C-MoS 2 /N-G) integrated electrode via a hydrothermal-induced self-assembly process. The preformed carbon coated MoS 2 is strongly anchored on the porous nitrogen-doped graphene aerogel architecture. As an anode for lithium ion batteries, the C-MoS 2 /N-G electrode delivers a high first discharge capacity of 1600 mAh g −1 and maintains 900 mAh g −1 after 500 cycles at a current density of 200 mA g −1 . Impressively, superior high-rate capability is achieved for the C-MoS 2 /N-G with a reversible capacity of 500 mAh g −1 at a high current density of 4000 mA g −1 . Furthermore, the lithium storage mechanism of the obtained integrated electrode is investigated by ex-situ X-ray photoelectron spectroscopy and transmission electron microscopy in detail. [ABSTRACT FROM AUTHOR]
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- 2015
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9. Porous reduced graphene oxide sheet wrapped silicon composite fabricated by steam etching for lithium-ion battery application.
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Tang, H., Zhang, J., Zhang, Y.J., Xiong, Q.Q., Tong, Y.Y., Li, Y., Wang, X.L., Gu, C.D., and Tu, J.P.
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GRAPHENE oxide , *POROUS materials , *NANOPARTICLES , *LITHIATION , *ELECTRODES , *LITHIUM-ion batteries - Abstract
A novel of Si/porous reduced graphene oxide (rGO) composite is fabricated by steam etching of Si/rGO aerogel. The rGO sheets with nano-holes build a unique three-dimensional porous network and can encapsulate the Si nanoparticles. The porous structure of Si/rGO composite can reduce the transfer distance of Li ions and restrain the aggregation and destruction of Si particles. The in-situ transmission electron microscopy (TEM) observation demonstrates that the porous rGO sheets help the entire electrode to maintain highly conductive and facilitate the lithiation of Si nanoparticles. The composite electrode presents high specific capacity and good cycling stability (1004 mAh g −1 at 50 mA g −1 up to 100 cycles). [ABSTRACT FROM AUTHOR]
- Published
- 2015
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10. Synthesis and electrochemical performance of lithium vanadium phosphate and lithium vanadium oxide composite cathode material for lithium ion batteries.
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Li, Y., Bai, W.Q., Zhang, Y.D., Niu, X.Q., Wang, D.H., Wang, X.L., Gu, C.D., and Tu, J.P.
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LITHIUM-ion batteries , *ELECTROCHEMISTRY , *VANADIUM phosphate , *LITHIUM compounds , *CHEMICAL synthesis , *CATHODES , *SOL-gel processes , *COMPOSITE materials - Abstract
A novel 2Li 3 V 2 (PO 4 ) 3 ·LiV 3 O 8 composite with short rod and thin plate shapes is synthesized through sol–gel method followed by hydrothermal and solid–state reaction. LiV 3 O 8 is used as an additive to improve the capacity of Li 3 V 2 (PO 4 ) 3 . In the composite cathode, active impurity phase Li 0.3 V 2 O 5 is also present, which has little impact on the whole electrochemical properties. The 2Li 3 V 2 (PO 4 ) 3 ·LiV 3 O 8 composite delivers a high initial capacity of 162.8 mAh g −1 at a current density of 100 mA g −1 in the voltage range of 2.0–4.3 V. Furthermore, the composite with high crystallinity also shows high electrochemical reversibility and good rate capability. The diffusion coefficient of Li ions in the composite is in the range of 10 −11 –10 −9 cm 2 s −1 obtained from galvanostatic intermittent titration technique. [ABSTRACT FROM AUTHOR]
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- 2015
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11. Synthesis and electrochemical performance of 0.6Li3V2(PO4)3·0.4Li–V–O composite cathode material for lithium ion batteries.
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Li, Y., Bai, W.Q., Wang, D.H., Niu, X.Q., Zhang, Y.D., Tang, H., Wang, X.L., Gu, C.D., and Tu, J.P.
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LITHIUM-ion batteries , *ELECTROCHEMICAL electrodes , *SOLID state chemistry , *METALLIC composites , *LITHIUM compounds , *CHEMICAL synthesis , *SCANNING electron microscopy - Abstract
A novel 0.6Li 3 V 2 (PO 4 ) 3 ·0.4Li–V–O composite cathode material is synthesized by sol-gel method followed by solvothermal and solid state reaction. The morphology and structure of the composite are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photo-electron spectroscopy (XPS). The composite particles are well-crystallized and present uniform nanoplate alike. Except Li 3 V 2 (PO 4 ) 3 phase, LiV 2 O 5 and VO 2 are also present in the composite. The 0.6Li 3 V 2 (PO 4 ) 3 ·0.4Li–V–O electrode delivers a discharge capacity of 149.3 mAh g −1 at 50 mAg −1 between 2.0 V and 4.3 V, and has higher rate property than Li 3 V 2 (PO 4 ) 3 . The diffusion coefficients of Li ions in the composite are in the range of 10 −9.5 − 10 −7.5 cm 2 s −1 obtained from galvanostatic intermittent titration technique (GITT). [ABSTRACT FROM AUTHOR]
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- 2015
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12. Combustion synthesized rod-like nanostructure hematite with enhanced lithium storage properties.
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Xiong, Q.Q., Shi, S.J., Tang, H., Wang, X.L., Gu, C.D., and Tu, J.P.
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SELF-propagating high-temperature synthesis , *NANOROD synthesis , *NANOSTRUCTURED materials , *HEMATITE , *LITHIUM-ion batteries , *ENERGY storage - Abstract
Fe 2 O 3 nanorods are synthesized by combustion method using alcohol as both solvent and fuel, which is a facile and effective strategy for the large-scale and inexpensive fabrication. The Fe 2 O 3 nanorods are with the well distributed diameters of 20–30 nm and length ranging from 80 to 100 nm. As an anode material for lithium-ion batteries, the Fe 2 O 3 nanorod electrode delivers a high discharge capacity of 761.7 mA h g −1 after 60 cycles at 500 mA g −1 , and 727.2 mA h g −1 at a high current density of 2000 mA g −1 . The good electrochemical performance is attributed to the sufficient contact of active material and electrolyte, large surface area, and short diffusion length of Li + . [ABSTRACT FROM AUTHOR]
- Published
- 2015
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13. Hollow Li1.2Mn0.5Co0.25Ni0.05O2 microcube prepared by binary template as a cathode material for lithium ion batteries.
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Shi, S.J., Lou, Z.R., Xia, T.F., Wang, X.L., Gu, C.D., and Tu, J.P.
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LITHIUM compounds , *LITHIUM-ion batteries , *HOLLOW fibers , *CHEMICAL templates , *CATHODES , *IMPEDANCE spectroscopy - Abstract
Abstract: Novel Li1.2Mn0.5Co0.25Ni0.05O2 microcube is prepared through a simple binary template method. After calcined at 800 °C, lithium and nickel are permeated into the cathode material and a well-crystallized Li-rich layered oxide is obtained. Furthermore, hollow circle cube architecture is formed due to the decomposing of the carbonate. As a cathode material for lithium ion batteries (LIBs), the oxide with such architecture can deliver high initial discharge capacity of 272.9 mAh g−1 at a current density of 20 mA g−1. High reversible discharge capacities of 208 mAh g−1 and 110 mAh g−1 are obtained at a current density of 200 mA g−1 and 2000 mA g−1, respectively. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) are performed to further study the hollow Li1.2Mn0.5Co0.25Ni0.05O2 microcube. It is remarkable that such architecture makes the Li-rich layered oxide Li1.2Mn0.5Co0.25Ni0.05O2 a promising cathode material for LIBs. [Copyright &y& Elsevier]
- Published
- 2014
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14. Facile synthesis of cookies-shaped LiV3O8 cathode materials with good cycling performance for lithium-ion batteries.
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Huang, S., Wang, X.L., Lu, Y., Jian, X.M., Zhao, X.Y., Tang, H., Cai, J.B., Gu, C.D., and Tu, J.P.
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CHEMICAL synthesis , *LITHIUM compounds , *LITHIUM-ion batteries , *PERFORMANCE of electric batteries , *CATHODES , *SOL-gel processes , *CURRENT density (Electromagnetism) , *DISSOLUTION (Chemistry) , *CRYSTALLINITY - Abstract
Highlights: [•] Cookies-shaped LiV3O8 material was synthesized by a facile sol–gel method. [•] The compound shows high capacity retentions at different current densities. [•] The good performance is due to high crystallinity and little dissolution of vanadium. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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15. Oxalic acid-assisted combustion synthesized LiVO3 cathode material for lithium ion batteries.
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Jian, X.M., Wenren, H.Q., Huang, S., Shi, S.J., Wang, X.L., Gu, C.D., and Tu, J.P.
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LITHIUM-ion batteries , *OXALIC acid , *CHEMICAL synthesis , *LITHIUM compounds , *CATHODES , *CRYSTALLIZATION , *ELECTROCHEMISTRY - Abstract
Abstract: LiVO3 materials are synthesized by combustion method with oxalic acid as fuel. Owing to its relatively low crystallization and small particle size, the LiVO3 calcined at 450 °C for 2 h displays optimal electrochemical performances, delivering a high discharge capacity of 298.4 mAh g−1 and 262.5 mAh g−1 between 1.0 and 3.5 V at a current density of 50 mA g−1 and 500 mA g−1 respectively, and exhibiting good cyclic stability. In this work, the chemical diffusion coefficient of Li+ (D Li+) in the LiVO3 electrode is determined by electrochemical impedance spectroscopy (EIS) and galvanostatic intermittent titration technique (GITT). The value calculated by EIS is in the range of 10−9–10−8 cm2 s−1, while it calculated by GITT is 10−9.5–10−8 cm2 s−1. [Copyright &y& Elsevier]
- Published
- 2014
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16. One-dimension MnCo2O4 nanowire arrays for electrochemical energy storage.
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Li, L., Zhang, Y.Q., Liu, X.Y., Shi, S.J., Zhao, X.Y., Zhang, H., Ge, X., Cai, G.F., Gu, C.D., Wang, X.L., and Tu, J.P.
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MANGANESE compounds , *NANOWIRES , *ELECTROCHEMISTRY , *ENERGY storage , *LITHIUM-ion batteries , *THERMAL properties - Abstract
Highlights: [•] MnCo2O4 nanowire array is prepared by a fast and facile hydrothermal method. [•] MnCo2O4 nanowire array exhibits noticeable pseudocapacitive properties. [•] The as-prepared nanowire array is also a promising material for Li-ion batteries. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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17. Enhanced electrochemical properties of Al2O3-coated LiV3O8 cathode materials for high-power lithium-ion batteries.
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Huang, S., Tu, J.P., Jian, X.M., Lu, Y., Shi, S.J., Zhao, X.Y., Wang, T.Q., Wang, X.L., and Gu, C.D.
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ELECTROCHEMISTRY , *ALUMINUM compounds , *METAL coating , *LITHIUM-ion batteries , *THERMOLYSIS , *CURRENT density (Electromagnetism) , *CHEMICAL synthesis , *PERFORMANCE of cathodes - Abstract
Abstract: Surface modified-LiV3O8 cathode materials with Al2O3 are successfully synthesized via a facile thermolysis process. The 0.5 wt.% Al2O3-coated LiV3O8 exhibits an enhanced cyclic stability at various charge–discharge current densities. At a current density of 100 mA g−1, it delivers an initial specific discharge capacity of 283.1 mAh g−1 between 2.0 and 4.0 V. Moreover, high capacities of 139.4 and 118.5 mAh g−1 are obtained at the 100th cycle at current densities of 2000 and 3000 mA g−1, respectively. The improved electrochemical performance is attributed to the Al2O3 coating, which can hinder the irreversible phase transformation and act as a protective layer to prevent the active material from direct contact with electrolyte. Furthermore, the formation of a Li–V–Al–O solid solution at the LiV3O8/Al2O3 interface provides a fast Li+ diffusion path which is of benefit to the electrochemical behaviors. [Copyright &y& Elsevier]
- Published
- 2014
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18. Preparation and characterization of macroporous Li1.2Mn0.54Ni0.13Co0.13O2 cathode material for lithium-ion batteries via aerogel template.
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Shi, S.J., Tu, J.P., Tang, Y.Y., Zhang, Y.Q., Wang, X.L., and Gu, C.D.
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POROUS materials , *LITHIUM-ion batteries , *AEROGELS , *CHEMICAL templates , *NICKEL oxides , *CRYSTALLINITY , *CHEMICAL reactions - Abstract
Macroporous Li1.2Mn0.54Ni0.13Co0.13O2 cathode materials with high crystallinity and hexagonal ordering are synthesized by aerogel template followed by solid state reaction. High discharge capacities of 244.0 mA h g−1 and 153.9 mA h g−1 are obtained for the Li-rich layered oxide synthesized at 800 °C at current densities of 200 mA g−1 and 2000 mA g−1 between 2.0 V and 4.8 V. Increasing the synthesis temperature to 900 °C, the macroporous Li1.2Mn0.54Ni0.13Co0.13O2 delivers a high discharge capacity of 220.2 mA h g−1 at a current density of 200 mA g−1 with a capacity retention of 89.1% after 50 cycles, 129.8 mA h g−1 at a current density of 2000 mA g−1 and almost no capacity fading after 120 cycles. The diffusion coefficients of Li+ in the Li-rich layered oxide determined by galvanostatic intermittent titration technique are in the range of 5.0 × 10−18−8.0 × 10−14 cm2 s−1. Electrochemical impedance spectroscopy indicates that the macroporous structure with good particle contact of the layered oxide can improve its rate capability and cyclic stability. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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19. Hierarchical Fe2O3@Co3O4 nanowire array anode for high-performance lithium-ion batteries.
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Xiong, Q.Q., Xia, X.H., Tu, J.P., Chen, J., Zhang, Y.Q., Zhou, D., Gu, C.D., and Wang, X.L.
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IRON oxides , *COBALT oxides , *NANOWIRES , *ANODES , *LITHIUM-ion batteries , *PERFORMANCE of fuel cells , *HYDROLYSIS - Abstract
Abstract: A hierarchically Fe2O3@Co3O4 nanowire array is prepared by the aid of hydrothermal synthesis and sacrificial hydrolysis method. The obtained nanowire array shows hierarchical porosity and large surface area. The resulted Fe2O3@Co3O4 nanowire array is evaluated as an anode material for Li ion batteries, which exhibits high capacity and good cycle stability (1005.1 mAh g−1 after 50 cycles at a current density of 200 mA g−1) and an excellent rate performance, mainly owing to the unique hierarchical nanowire architecture and an elegant synergistic effect of two electrochemically active materials. The developed strategy can be readily generalized to construct other multifunctional hybrid nanostructures, which will be promising materials for high-performance electrochemical devices. [Copyright &y& Elsevier]
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- 2013
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20. Effect of Sm2O3 modification on Li[Li0.2Mn0.56Ni0.16Co0.08]O2 cathode material for lithium ion batteries.
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Shi, S.J., Tu, J.P., Zhang, Y.J., Zhang, Y.D., Zhao, X.Y., Wang, X.L., and Gu, C.D.
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SAMARIUM compounds , *LITHIUM-ion batteries , *CATHODES , *CHARGE transfer , *COATING processes - Abstract
Highlights: [•] Sm2O3 is well coated on Li[Li0.2Mn0.56Ni0.16Co0.08]O2 by simple wet chemical method. [•] The coated sample exhibits high capacity of 234.5mAhg−1 at 1C. [•] Capacity retention of 91.5% is obtained at 1C (200mAg−1) after 80 cycles 25°C. [•] EIS shows the thin Sm2O3 layer mainly reduces the charge transfer resistance. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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21. Synthesis and electrochemical performance of LiVO3 cathode materials for lithium ion batteries
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Jian, X.M., Tu, J.P., Qiao, Y.Q., Lu, Y., Wang, X.L., and Gu, C.D.
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CHEMICAL synthesis , *LITHIUM compounds , *LITHIUM-ion batteries , *PERFORMANCE of storage batteries , *ELECTROCHEMICAL electrodes , *BALL mills , *SOLID state batteries , *GALVANOSTAT , *VOLUMETRIC analysis - Abstract
Abstract: LiVO3 is synthesized via a ball-milling route followed by a solid-state reaction at different temperatures. As cathode materials for lithium ion batteries, the electrochemical performances of LiVO3 are investigated by galvanostatic charge–discharge test and electrochemical impedance spectroscopy (EIS). The LiVO3 compound synthesized at 350 °C possesses the optimal performance, delivering an initial discharge capacity of 302.5 mAh g−1 between 1.0 V and 3.5 V at a current density of 50 mA g−1, and exhibiting a good cycling stability. Li-ion diffusion coefficient of 10−9.5–10−8 cm2 s−1 in the LiVO3 electrode is calculated by galvanostatic intermittent titration technique (GITT). The good performances can be attributed to its relatively low crystallization and small particle size. [Copyright &y& Elsevier]
- Published
- 2013
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22. Polyacrylamide-assisted freeze drying synthesis of hierarchical plate-arrayed LiV3O8 for high-rate lithium-ion batteries
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Huang, S., Lu, Y., Wang, T.Q., Gu, C.D., Wang, X.L., and Tu, J.P.
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LITHIUM-ion batteries , *POLYACRYLAMIDE , *AMIDE synthesis , *DRYING , *LITHIUM compounds , *HIERARCHICAL Bayes model , *SURFACE active agents - Abstract
Abstract: Hierarchical plate-arrayed LiV3O8 is synthesized by freeze drying method with polyacrylamide (PAM) as surfactant followed by calcination at 500 °C. As a cathode material for lithium-ion batteries, the plate-arrayed LiV3O8 delivers an initial discharge capacity of 255.2 mAh g−1 between 2.0 and 4.0 V at the current density of 50 mA g−1, and possesses a capacity retention of 88.7% after 60 cycles. Moreover, high discharge capacities of 145.2, 133.7 and 111.8 mAh g−1 can still be obtained after the 200th cycle at current densities of 600, 1500 and 3000 mA g−1, respectively. Electrochemical impedance spectroscopy (EIS) test indicates that the LiV3O8 electrode always has very low impedance during the 3rd to 180th cycles. The improved electrochemical performance is attributed to the high crystallinity and uniform arrayed structure of LiV3O8, which can facilitate the fast electron transport and Li ion diffusion in the electrode. [Copyright &y& Elsevier]
- Published
- 2013
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23. Enhanced electrochemical performance of LiF-modified LiNi1/3Co1/3Mn1/3O2 cathode materials for Li-ion batteries
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Shi, S.J., Tu, J.P., Tang, Y.Y., Zhang, Y.Q., Liu, X.Y., Wang, X.L., and Gu, C.D.
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ELECTROCHEMICAL analysis , *LITHIUM-ion batteries , *NICKEL alloys , *CATHODES , *METALLIC surfaces , *ANNEALING of metals , *METAL microstructure - Abstract
Abstract: LiF is successful used to modify the surface of layered LiNi1/3Co1/3Mn1/3O2 via a wet chemical method followed by an annealing process. The lattice structure of LiNi1/3Co1/3Mn1/3O2 is not changed distinctly after modification and part of F− dopes into the surface lattice of the oxide. The LiF-modified oxide exhibits capacity retentions of 97.5% at 0.1 C at room temperature and 93.5% at 1 C at 60 °C after 50 cycles, and delivers a high discharge capacity of 137 mAh g−1 at 10 C at room temperature. Furthermore, it has reversible capacities of 124.4 mAh g−1 at 1 C at 0 °C and 85.6 mAh g−1 at 0.1 C at −20 °C, respectively. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) tests show that the LiF-modified layer can reduce the dissolution of metal ions in the electrode and enhance the conductivity of the oxide surface through partly F-substitution. LiF modification will be promising for the application of layered oxide for lithium ion batteries. [Copyright &y& Elsevier]
- Published
- 2013
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24. Enhanced cycling stability of Li[Li0.2Mn0.54Ni0.13Co0.13]O2 by surface modification of MgO with melting impregnation method
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Shi, S.J., Tu, J.P., Tang, Y.Y., Liu, X.Y., Zhang, Y.Q., Wang, X.L., and Gu, C.D.
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FUSION (Phase transformation) , *TRANSMISSION electron microscopy , *ELECTROCHEMICAL analysis , *LITHIUM-ion batteries , *SOLID state chemistry , *MAGNESIUM oxide , *IMPEDANCE spectroscopy , *SURFACE chemistry - Abstract
Abstract: MgO-coated Li[Li0.2Mn0.54Ni0.13Co0.13]O2 was synthesized via melting impregnation method followed by a solid state reaction. Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) show that the MgO layer is well coated on the surface of the layered oxide particles. Although the initial discharge capacity of Li[Li0.2Mn0.54Ni0.13Co0.13]O2 with proper MgO modification decreases compared to the bare one, the 2wt.% MgO coated cathode exhibits the excellent cycling stability with capacity retention of 96.4% at a current density of 200mAg−1 after 100 cycles at room temperature and 94.3% after 50 cycles at 60°C. Electrochemical impedance spectroscopy (EIS) shows that the thin MgO layer mainly reduces the charge transfer resistance and stabilizes the surface structure of active material during cycling. Melting impregnation method is promising for MgO coating to improving the cycling stability of Li-rich layered oxide cathode for Li-ion batteries. [Copyright &y& Elsevier]
- Published
- 2013
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25. MnO/reduced graphene oxide sheet hybrid as an anode for Li-ion batteries with enhanced lithium storage performance
- Author
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Mai, Y.J., Zhang, D., Qiao, Y.Q., Gu, C.D., Wang, X.L., and Tu, J.P.
- Subjects
- *
LITHIUM-ion batteries , *MANGANESE oxides , *GRAPHENE , *ANODES , *ENERGY storage , *TRANSITION metal oxides , *NANOPARTICLES , *ELECTRIC potential , *IMPEDANCE spectroscopy - Abstract
Abstract: Relatively small hysteresis in voltage, appropriate electromotive force and low average delithiation voltage make MnO, among many transition metal oxides. MnO/reduced graphene oxide sheet (MnO/RGOS) hybrid is synthesized by a two-step electrode design consisting of liquid phase deposition of MnCO3 nanoparticles on the surface of graphene oxide sheets followed by heat treatment in flowing nitrogen. As an anode for Li-ion batteries, the MnO/RGOS hybrid electrode shows a reversible capacity of 665.5 mA h g−1 after 50 cycles at a current density of 100 mA g−1 and delivers 454.2 mA h g−1 at a rate of 400 mA g−1, which is obviously better than that of bare MnO electrode. Those reasons for such enhanced electrochemical properties are investigated by galvanostatic intermittent titration technique (GITT) as well as electrochemical impedance spectroscopy (EIS). The probable origins, in the term of thermodynamic and kinetic factors, for the marked hysteresis in voltage observed between charge and discharge are also discussed. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
26. Improved electrochemical performance of porous Fe3O4/carbon core/shell nanorods as an anode for lithium-ion batteries
- Author
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Xiong, Q.Q., Lu, Y., Wang, X.L., Gu, C.D., Qiao, Y.Q., and Tu, J.P.
- Subjects
- *
ELECTROCHEMICAL analysis , *POROUS materials , *IRON oxides , *CARBON , *NANORODS , *ANODES , *LITHIUM-ion batteries - Abstract
Abstract: Porous Fe3O4/C core/shell nanorods have been prepared by a facile hydrothermal method using porous Fe2O3 nanorods as the precursor and glucose as the carbon source. The Fe3O4/C nanorods possess a uniform size with 50–80nm in diameter and 300–500nm in length, and are homogenously coated by amorphous carbon layer. The porous nanorods greatly increase the electrical contact, thus facilitating the Li-ion and electron transportation, and enhancing the reactivity of the electrode. Also, the carbon layer can effectively limit the volume expansion and detachment of Fe3O4, and thus increase its structure stability during cycling. In the context of lithium storage behavior, the Fe3O4/C nanorod electrode shows high capacity and good cycle stability, as well as enhanced rate performance. After 50 cycles, the reversible capacity of the porous Fe3O4/C nanorods is 762.1mAhg−1 at 0.1C and 597.2mAhg−1 at 0.5C, much higher than that of α-Fe2O3 nanorods (276.4mAhg−1) and Fe3O4 nanoparticles (307.9mAhg−1). At a high rate of 1C, the specific capacity of Fe3O4/C nanorods is still as high as 630.1mAhg−1. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
27. Freeze-drying synthesis of Li3V2(PO4)3/C cathode material for lithium-ion batteries
- Author
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Qiao, Y.Q., Wang, X.L., Mai, Y.J., Xia, X.H., Zhang, J., Gu, C.D., and Tu, J.P.
- Subjects
- *
FREEZE-drying , *LITHIUM compounds , *CATHODES , *LITHIUM-ion batteries , *PARTICLE size distribution , *ELECTROCHEMISTRY - Abstract
Abstract: Li3V2(PO4)3/C cathode material was synthesized by using a freeze-drying method followed by carbon-thermal reduction. This as-prepared material has a uniform particle size distribution and a well carbon coating on the surface of Li3V2(PO4)3 particles. The Li3V2(PO4)3/C exhibits good electrochemical performance and cycling stability. Between 3.0 and 4.3V, the composite delivered a reversible capacity of 125.2mAhg−1 at a charge–discharge rate of 1.48C (1C=133mAg−1) and without obviously capacity fading after 100 cycles. Even at 14.8C and 29.6C rates, it can still deliver discharge capacities of 105.6mAhg−1 and 93.3mAhg−1, and the discharge capacities of 84.5 and 60.5mAhg−1 are sustained after 500 cycles, respectively. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
28. NiO–graphene hybrid as an anode material for lithium ion batteries
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Mai, Y.J., Shi, S.J., Zhang, D., Lu, Y., Gu, C.D., and Tu, J.P.
- Subjects
- *
LITHIUM-ion batteries , *NICKEL compounds , *GRAPHENE , *CHEMICAL synthesis , *THERMODYNAMICS , *VOLUMETRIC analysis , *CHEMICAL kinetics - Abstract
Abstract: A NiO–graphene hybrid is synthesized by a liquid phase deposition method. As an anode material for lithium ion batteries, the cyclic stability and rate capability of NiO is significantly improved after the incorporation of graphene sheets. The NiO–graphene hybrid electrode delivers a capacity of 646.1mAhg−1 after 35cycles at a current density of 100mAg−1, corresponding to 86.3% capacity retention. When the current density is increased to 400 and 800mAg−1, it still maintains a capacity of 509 and 368.5mAhg−1, respectively. The thermodynamic and kinetic properties of NiO electrodes with and without graphene are investigated by galvanostatic intermittent titration technique. The relationship between the rate and voltage hysteresis is also discussed. The polarization of both the electrodes in all cases obeys ohmic rule in the present rate range. The incorporation of graphene sheets can partly reduce the voltage polarization thereby the voltage hysteresis with increasing the current density. However, the extrapolation to zero current ends up in an approximate residual voltage for both the NiO electrodes. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
29. Self-supported nickel-coated NiO arrays for lithium-ion batteries with enhanced capacity and rate capability
- Author
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Mai, Y.J., Xia, X.H., Chen, R., Gu, C.D., Wang, X.L., and Tu, J.P.
- Subjects
- *
TRANSITION metal oxides , *METAL coating , *LITHIUM-ion batteries , *CHEMICAL vapor deposition , *MAGNETRON sputtering , *ELECTRIC conductivity , *MICROSTRUCTURE , *HYSTERESIS - Abstract
Abstract: 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. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
30. Effect of carbon coating on electrochemical performance of Li1.048Mn0.381Ni0.286Co0.286O2 cathode material for lithium-ion batteries
- Author
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Shi, S.J., Tu, J.P., Mai, Y.J., Zhang, Y.Q., Gu, C.D., and Wang, X.L.
- Subjects
- *
LITHIUM-ion batteries , *LITHIUM compounds , *CATHODES , *MATERIALS , *CARBON , *SURFACE coatings , *PRECIPITATION (Chemistry) - Abstract
Abstract: Carbon-coated layered oxide Li1.048Mn0.381Ni0.286Co0.286O2 is prepared by combining a co-precipitation and a direct current magnetron sputtering. TEM images show that the carbon layer is relatively well coated on the surface of oxide particles. The Li1.048Mn0.381Ni0.286Co0.286O2/C composite delivers an initial discharge capacity of 203.2mAhg−1 between 2.5 and 4.5V at 0.1C, and 94% of the initial discharge capacity can be retained after 100 cycles. Moreover, the carbon-coated oxide exhibits noticeable high-rate capacity of 145mAhg−1 at 5C, much higher than the pristine one (103mAhg−1 at 5C). The improved discharge capacity and cycle performance are attributed to the carbon coating, which protects the Li-rich cathode material from reacting with the electrolyte and retarding the incrassation of SEI film on the surface of oxide particles. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
31. The low and high temperature electrochemical performances of Li3V2(PO4)3/C cathode material for Li-ion batteries
- Author
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Qiao, Y.Q., Tu, J.P., Wang, X.L., and Gu, C.D.
- Subjects
- *
HIGH temperatures , *ELECTROCHEMISTRY , *LITHIUM-ion batteries , *CATHODES , *CHEMICAL reduction , *ELECTRIC conductivity , *TEMPERATURE effect - Abstract
Abstract: Li3V2(PO4)3/C cathode material is synthesized by a carbon-thermal reduction method using polyvinyl alcohol as carbon source at 700°C. The Li3V2(PO4)3/C electrode presents a high initial discharge capacity of 84.3, 111.1, 128.7, 129.2 and 132.1mAhg−1 at −20, 0, 25, 40 and 65°C between 3.0 and 4.3V, and 118.9, 132.1, 187.6, 180.3 and 172.2mAhg−1 between 3.0 and 4.8V at 0.1C, respectively. However, the electrode only delivers small discharge capacities at −20°C at 10C rate. The capacity fade at low temperatures is mainly attributed to the reduced ionic and electronic conductivity of the electrolyte, the increased impendence of solid electrolyte interface (SEI) and charge-transfer resistance on the electrolyte–electrode interfaces. At higher temperatures, the capacity increases with increasing temperature between 3.0 and 4.3V, but decreases between 3.0 and 4.8V. In the potential range of 3.0–4.8V, the larger crystal structural distortion and non-uniformity of SEI layer at high temperatures may be the main reasons for the capacity loss. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
32. Synthesis and electrochemical performance of rod-like LiV3O8 cathode materials for rechargeable lithium batteries
- Author
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Qiao, Y.Q., Wang, X.L., Zhou, J.P., Zhang, J., Gu, C.D., and Tu, J.P.
- Subjects
- *
LITHIUM-ion batteries , *ELECTROCHEMICAL analysis , *LITHIUM compounds , *INORGANIC synthesis , *CATHODES , *STORAGE batteries , *COMPOSITE materials - Abstract
Abstract: Rod-like LiV3O8 composites have been fabricated by using a carbamide-assisted rheological phase reaction method. The electrochemical performances of the LiV3O8 materials prepared under different conditions are investigated by cyclic voltammograms, galvanostatic charge–discharge tests and electrochemical impedance spectroscopy (EIS). The rod-like LiV3O8 calcined at 500°C has the optimal performance, delivering an initial discharge capacity of 273.6 and 250.4mAhg−1 between 2.0V and 4.0V at a current density of 50 and 120mAg−1, respectively. After 60 cycles by applying 50mAg−1, a discharge capacity of 213.0mAhg−1 is obtained, showing a good cycling performance. The EIS studies show that the 500°C-LiV3O8 electrode has very low impedance increase during 1st to 240th discharge-charge cycles. All these results indicate that the rod-like LiV3O8 compound has a promising application as the cathode material for rechargeable lithium batteries. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
33. Influence of particle size on electrochemical performances of pyrite FeS2 for Li-ion batteries
- Author
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Zhang, D., Tu, J.P., Xiang, J.Y., Qiao, Y.Q., Xia, X.H., Wang, X.L., and Gu, C.D.
- Subjects
- *
ELECTROCHEMICAL analysis , *PYRITES , *LITHIUM-ion batteries , *IRON compounds , *SULFIDE crystals , *SOLID state chemistry , *SURFACE area , *COMPARATIVE studies , *CHEMICAL kinetics - Abstract
Abstract: Well-crystallized FeS2 powders are synthesized via solid state reaction. Influence of particle size on electrochemical performances has been conducted. Compared with other anode materials, FeS2 powder with mean particle size of 0.28μm exhibits high coulombic efficiency, initial discharge specific capacity, low polarization and enhanced electrode process kinetics. The enhanced electrochemical properties are attributed to the dense powder packing, better electrical contact and relative stable structure during cycling process. Smaller FeS2 particles (0.078 and 0.071μm) have difficulty in dispersing and mixing with carbon black and binder and less dense packing state, leading to a decrease of reactive contact surface area and poor electrochemical performance. [Copyright &y& Elsevier]
- Published
- 2011
- Full Text
- View/download PDF
34. Synthesis of plate-like Li3V2(PO4)3/C as a cathode material for Li-ion batteries
- Author
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Qiao, Y.Q., Wang, X.L., Mai, Y.J., Xiang, J.Y., Zhang, D., Gu, C.D., and Tu, J.P.
- Subjects
- *
INORGANIC synthesis , *LITHIUM compounds , *CATHODES , *LITHIUM-ion batteries , *CHEMICAL reactions , *TRANSMISSION electron microscopy , *ELECTRIC potential , *ELECTRODES - Abstract
Abstract: Plate-like Li3V2(PO4)3/C composite is synthesized via a solution route followed by solid-state reaction. The Li3V2(PO4)3/C plates are 40–100nm in thicknesses and 2–10μm in lengths. TEM images show that a uniform carbon layer with a thickness of 5.3nm presents on the surfaces of Li3V2(PO4)3 plates. The apparent Li-ion diffusion coefficient of the plate-like Li3V2(PO4)3/C is calculated to be 2.7×10−8 cm2 s−1. At a charge–discharge rate of 3C, the plate-like Li3V2(PO4)3/C exhibits an initial discharge capacity of 125.2 and 133.1mAhg−1 in the voltage ranges of 3.0–4.3 and 3.0–4.8V, respectively. After 500 cycles, the electrodes still can deliver a discharge capacity of 111.8 and 97.8mAhg−1 correspondingly, showing a good cycling stability. [Copyright &y& Elsevier]
- Published
- 2011
- Full Text
- View/download PDF
35. Synthesis and improved electrochemical performances of porous Li3V2(PO4)3/C spheres as cathode material for lithium-ion batteries
- Author
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Qiao, Y.Q., Tu, J.P., Wang, X.L., Zhang, D., Xiang, J.Y., Mai, Y.J., and Gu, C.D.
- Subjects
- *
ELECTROCHEMISTRY , *POROUS materials , *LITHIUM-ion batteries , *CATHODES , *IMPEDANCE spectroscopy , *HYDRAZINE , *CHARGE exchange , *INORGANIC synthesis - Abstract
Abstract: Spherical Li3V2(PO4)3/C composites are synthesized by a soft chemistry route using hydrazine hydrate as the spheroidizing medium. The electrochemical properties of the materials are investigated by galvanostatic charge–discharge tests, cyclic voltammograms and electrochemical impedance spectrum. The porous Li3V2(PO4)3/C spheres exhibit better electrochemical performances than the solid ones. The spherical porous Li3V2(PO4)3/C electrode shows a high discharge capacity of 129.1 and 125.6mAhg−1 between 3.0 and 4.3V, and 183.8 and 160.9mAhg−1 between 3.0 and 4.8V at 0.2 and 1C, respectively. Even at a charge–discharge rate of 15C, this material can still deliver a discharge capacity of 100.5 and 121.5mAhg−1 in the potential regions of 3.0–4.3V and 3.0–4.8V, respectively. The excellent electrochemical performance can be attributed to the porous structure, which can make the lithium ion diffusion and electron transfer more easily across the Li3V2(PO4)3/electrolyte interfaces, thus resulting in enhanced electrode reaction kinetics and improved electrochemical performance. [Copyright &y& Elsevier]
- Published
- 2011
- Full Text
- View/download PDF
36. Co-doped NiO nanoflake arrays toward superior anode materials for lithium ion batteries
- Author
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Mai, Y.J., Tu, J.P., Xia, X.H., Gu, C.D., and Wang, X.L.
- Subjects
- *
COBALT , *DOPED semiconductors , *NICKEL compounds , *NANOSTRUCTURED materials , *ANODES , *LITHIUM-ion batteries , *THIN films , *ELECTRIC conductivity - Abstract
Abstract: Co-doped NiO nanoflake arrays with a cellular-like morphology are fabricated by low temperature chemical bath deposition. As anode material for lithium ion batteries (LIBs), the array film shows a capacity of 600mAhg−1 after 50 discharge/charge cycles at low current density of 100mAg−1, and it retains 471mAhg−1 when the current density is increased to 2Ag−1. Appropriate electrode configuration possesses some unique features, including high electrode–electrolyte contact area, direct contact between each naonflake and current collector, fast Li+ diffusion. The Co2+ partially substitutes Ni3+, resulting in an increase of holes concentration, and therefore improved p-type conductivity, which is useful to reduce charge transfer resistance during the charge/discharge process. The synergetic effect of these two parts can account for the improved electrochemical performance. [Copyright &y& Elsevier]
- Published
- 2011
- Full Text
- View/download PDF
37. Enhanced electrochemical performances of multi-walled carbon nanotubes modified Li3V2(PO4)3/C cathode material for lithium-ion batteries
- Author
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Qiao, Y.Q., Tu, J.P., Mai, Y.J., Cheng, L.J., Wang, X.L., and Gu, C.D.
- Subjects
- *
ELECTROCHEMISTRY , *CARBON nanotubes , *CATHODES , *LITHIUM-ion batteries , *POLYVINYL alcohol , *METALLIC composites , *SURFACE coatings , *PHOSPHATES , *PYROLYSIS - Abstract
Abstract: The multi-walled carbon nanotubes (MWCNTs) modified Li3V2(PO4)3/C composite is synthesized by polyvinyl alcohol (PVA) based carbon-thermal reduction method using MWCNTs as a highly conductive agent. PVA mainly supplies a reductive atmosphere to reduce V5+ and provides a network of carbon to inhibit the aggregation of Li3V2(PO4)3 particles. The amorphous carbon coating and MWCNTs co-modified composite shows excellent high-rate lithium intercalation/deintercalation property and cycling performance between 3.0 and 4.3V. The discharge capacities of 131.7 and 122.9mAhg−1 are obtained at rates of 1C and 10C, respectively, for the Li3V2(PO4)3/(C+MWCNTs). These improvements are attributed to the valid conducting networks of C+MWCNTs and the reduced Li3V2(PO4)3 particle size by the network carbon from the pyrolysis of PVA. [Copyright &y& Elsevier]
- Published
- 2011
- Full Text
- View/download PDF
38. Self-assembled sandwich-like NiO film and its application for Li-ion batteries
- Author
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Zhong, J., Wang, X.L., Xia, X.H., Gu, C.D., Xiang, J.Y., Zhang, J., and Tu, J.P.
- Subjects
- *
MOLECULAR self-assembly , *SANDWICH construction (Materials) , *LITHIUM-ion batteries , *INORGANIC synthesis , *METALLIC oxides , *ANODES , *THIN films , *AMMONIA , *CHEMICAL processes - Abstract
Abstract: NiO film with sandwich-like morphology is fabricated on nickel foam by a simple ammonia-evaporation process. Ammonia plays a major role in controlling the final geometry during this template- and surfactant-free synthesis. The obtained NiO film is constructed by regular triangular prisms with side length of 500nm. Each triangular prism is self-assembled by single crystalline platelets. As an anode for lithium ion battery, this NiO film electrode exhibits high discharge capacity and excellent cycling performance. The reversible capacity of the sandwich-like NiO film sustains 400mAhg−1 even after 50 cycles at 2C, much higher than that of the dense NiO film prepared by eletrodeposition (198mAhg−1). The high rate capability and reversibility of this NiO film can be attributed to its unique sandwich-like architecture. [Copyright &y& Elsevier]
- Published
- 2011
- Full Text
- View/download PDF
39. Smart construction of intimate interface between solid polymer electrolyte and 3D-array electrode for quasi-solid-state lithium ion batteries.
- Author
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Zhang, S.Z., Wang, X.L., Xia, X.H., Yao, Z.J., Xu, Y.J., Wang, D.H., Xie, D., Wu, J.B., Gu, C.D., and Tu, J.P.
- Subjects
- *
LITHIUM-ion batteries , *SUPERIONIC conductors , *ELECTRODES , *ETHYLENE glycol , *ELECTRIC batteries , *LITHIUM titanate , *ELECTROLYTES - Abstract
Interfacial issues have been the main obstacle to the development of solid-state batteries. In this work, we design a solid hybrid polymer electrolyte based on poly-(ethylene glycol) diacrylate and succinonitrile (PSSE) with a liquid state precursor. An intimate interface between PSSE and Li 4 Ti 5 O 12 @vertical graphene (LTO@VG) electrode with three-dimensional array structure is cleverly constructed by infiltrating fluid precursor of PSSE into vertical pores of LTO@VG followed by polymerization and solidification of PSSE. The quasi-solid-state LTO@VG//PSSE//Li and LiFePO 4 //PSSE//LTO@VG full cells exhibit superior electrochemical performance since the active materials are closely contacted by the conductive skeleton and ion-conductive electrolyte. The LTO@VG//PSSE//Li cells maintain 85.7% capacity retention after 400 cycles at 2 C and the LFP//PSSE//LTO@VG full cells still reach 99.0% capacity retention after 200 cycles at 0.5 C. This novel strategy for interface engineering paves the way for achieving high-performance solid-state batteries. • A hybrid solid polymer electrolyte with fluid precursor is fabricated. • Intimate interface between 3D-array electrode and solid electrolyte is constructed. • Quasi-solid-state battery with excellent electrochemical performance is realized. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
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