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1.
Huang Yudai Qi Yanling Jia Dianzeng Wang Xingchao Guo Zaiping Cho Won Il 《Journal of Solid State Electrochemistry》2012,16(5):2011-2016
Li4Ti5O12−x
Cl
x
(0 ≤ x ≤ 0.3) compounds were synthesized successfully via high temperature solid-state reaction. X-ray diffraction and scanning
electron microscopy were used to characterize their structure and morphology. Cyclic voltammetry, electrochemical impedance
spectroscopy, and charge/discharge cycling performance tests were used to characterize their electrochemical properties. The
results showed that the Li4Ti5O12−x
Cl
x
(0 ≤ x ≤ 0.3) compounds were well-crystallized pure spinel phase and that the grain sizes of the samples were about 3–8 μm. The
Li4Ti5O11.8Cl0.2 sample presented the best discharge capacity among all the samples and showed better reversibility and higher cyclic stability
compared with pristine Li4Ti5O12. When the discharge rate was 0.5 C, the Li4Ti5O11.8Cl0.2 sample presented the superior discharge capacity of 148.7 mAh g−1, while that of the pristine Li4Ti5O12 was 129.8 mAh g−1; when the discharge rate was 2 C, the Li4Ti5O11.8Cl0.2 sample presented the discharge capacity of 120.7 mAh g−1, while that of the pristine Li4Ti5O12 was only 89.8 mAh g−1. 相似文献
2.
Spinel Li4Ti5 − x
Zr
x
O12/C (x = 0, 0.05) were prepared by a solution method. The structure and morphology of the as-prepared samples were characterized
by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The electrochemical performances
including charge–discharge (0–2.5 V and 1–2.5 V), cyclic voltammetry, and ac impedance were also investigated. The results
revealed that the Li4Ti4.95Zr0.05O12/C had a relatively smaller particle size and more regular morphology than that of Li4Ti5O12/C. Zr4+ doping enhanced the ability of lithium-ion diffusion in the electrode. It delivered a discharge capacity 289.03 mAh g−1 after 50 cycles for the Zr4+-doped Li4Ti5O12/C while it decreased to 264.03 mAh g−1 for the Li4Ti5O12/C at the 0.2C discharge to 0 V. Zr4+ doping did not change the electrochemical process, instead enhanced the electronic conductivity and ionic conductivity. The
reversible capacity and cycling performance were effectively improved especially when it was discharged to 0 V. 相似文献
3.
Yaomin Zhao Guoqun Liu Ling Liu Zhiyu Jiang 《Journal of Solid State Electrochemistry》2009,13(5):705-711
Li4Ti5O12 thin-film anode with high discharge capacity and excellent cycle stability for rechargeable lithium ion batteries was prepared
successfully by using ink-jet printing technique. The prepared Li4Ti5O12 thin film were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray
photoelectron spectroscopy, cyclic voltammograms, and galvanostatic charge–discharge measurements. It was found that the average
thickness of 10-layer Li4Ti5O12 film was about 1.7~1.8 μm and the active material Li4Ti5O12 in the thin film was nano-sized about 50–300 nm. It was also found that the prepared Li4Ti5O12 thin film exhibited a high discharge capacity of about 174 mAh/g and the discharge capacity in the 300th cycle retained 88%
of the largest discharge capacity at a current density of 10.4 μA/cm2 in the potential range of 1.0–2.0 V. 相似文献
4.
Preparation of Li4Ti5O12 Yolk–Shell Powders by Spray Pyrolysis and their Electrochemical Properties
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We have reported for the first time the preparation of yolk–shell‐structured Li4Ti5O12 powders for use as anode materials in lithium‐ion batteries. One Li4Ti5O12 yolk–shell‐particle powder is directly formed from each droplet containing lithium, titanium, and carbon components inside the hot wall reactor maintained at 900 °C. The precursor Li4Ti5O12 yolk–shell‐particle powders, which are directly prepared by spray pyrolysis, have initial discharge and charge capacities of 155 and 122 mA h g?1, respectively, at a current density of 175 mA g?1. Post‐treatment of the yolk–shell‐particle powders at temperatures of 700 and 800 °C improves the initial discharge and charge capacities. The initial discharge capacities of the Li4Ti5O12 powders with a yolk–shell structure and a dense structure post‐treated at 800 °C are 189 and 168 mA h g?1, respectively. After 100 cycles, the corresponding capacities are 172 and 152 mA h g?1, respectively (retentions of 91 and 90 %). 相似文献
5.
Bingbing Tian Hongfa Xiang Le Zhang Haihui Wang 《Journal of Solid State Electrochemistry》2012,16(1):205-211
Li4Ti4.95Nb0.05O12 is synthesized by a citric acid-assistant sol–gel method. X-ray diffraction (XRD) reveals that highly crystalline Li4Ti4.95Nb0.05O12 without any impurity is obtained. The electrochemical performances of the Li4Ti4.95Nb0.05O12 and the Li4Ti5O12 in the range from 0 to 2.5 V are investigated. The Li4Ti4.95Nb0.05O12 presents a higher specific capacity and better cycling stability than the Li4Ti5O12 due to the improved conductivity. The Li4Ti4.95Nb0.05O12 exhibits a capacity as high as 231.2 mAh g−1 after 100 cycles, which is much higher than the Li4Ti5O12 (111.1 mAh g−1). The effect of Nb-doping on electrochemical performance of Li4Ti5O12 discharged to 0 V has also been discussed. 相似文献
6.
Yan-Jing Hao Yan-Ying Wang Qiong-Yu Lai Yan Zhao Lian-Mei Chen Xiao-Yang Ji 《Journal of Solid State Electrochemistry》2009,13(6):905-912
Spinel Li4Mn5O12 nanoparticles have been prepared by a very simple sol–gel method. Various initial conditions were studied in order to find
the optimal conditions for the synthesis of pure Li4Mn5O12. X-ray diffraction results showed that spinel Li4Mn5O12 was obtained at a low temperature of 300 °C without any miscellaneous phase. Scanning electron microscope analyses indicated
that the prepared Li4Mn5O12 powders had a uniform morphology with average particle size of about 50 and 100 nm. The prepared sample was firstly used
as a cathode material in an asymmetric Li4Mn5O12/AC supercapacitor in aqueous electrolyte. The capacitive properties of the hybrid supercapacitor were tested by cyclic voltammetry,
electrochemical impedance spectroscopy, and galvanostatic charge–discharge tests. The results showed that Li4Mn5O12 annealed at 450 °C for 4 h exhibited the best electrochemical capacitive performance within the potential range of 0–1.4 V
in 1 M Li2SO4 solution. A maximum specific capacitance of 43 F g−1 based on the total active material weight of the two electrodes was obtained for the Li4Mn5O12/AC supercapacitor at a current density of 100 mA g−1. The capacitor showed excellent cycling performance and structure stability via 1,000 cycles. 相似文献
7.
Feng Yu Jingjie Zhang Yanfeng Yang Guangzhi Song 《Journal of Solid State Electrochemistry》2010,14(5):883-888
Composite Li3V2(PO4)3/C cathode material can be synthesized by spray-drying and carbothermal method. The monoclinic-phase Li3V2(PO4)3/C was prepared with the process of double spray drying at 260 °C and subsequent heat treatment at 750 °C for 12 h. The results
indicate that the Li3V2(PO4)3/C presents large reversible discharge capacity of 121.9 mA h g−1 and charge capacity of 131.8 mA h g−1 at the current density of C/5, good rate capability with 61.1 mA h g−1 at 20C, and excellent capacity retention rate close to 100% at various current densities in the region of 3.0–4.3 V. 相似文献
8.
Lilong Xiong Youlong Xu Cheng Zhang Zhengwei Zhang Jiebin Li 《Journal of Solid State Electrochemistry》2011,15(6):1263-1269
Ti-doped spinel LiMn2O4 is synthesized by solid-state reaction. The X-ray photoelectron spectroscopy and X-ray diffraction analysis indicate that
the structure of the doped sample is Li( Mn3 + Mn1 - x 4 + Tix4 + )O4 {\hbox{Li}}\left( {{\hbox{M}}{{\hbox{n}}^{3 + }}{\hbox{Mn}}_{1 - x\,}^{4 + }{\hbox{Ti}}_x^{4 + }} \right){\hbox{O}}{}_4 . The first principle-based calculation shows that the lattice energy increases as Ti doping content increases, which indicates
that Ti doping reinforces the stability of the spinel structure. The galvanostatic charge–discharge results show that the
doped sample LiMn1.97Ti0.03O4 exhibits maximum discharge capacity of 135.7 mAh g−1 (C/2 rate). Moreover, after 70 cycles, the capacity retention of LiMn1.97Ti0.03O4 is 95.0% while the undoped sample LiMn2O4 shows only 84.6% retention under the same condition. Additionally, as charge–discharge rate increases to 12C, the doped sample
delivers the capacity of 107 mAh g−1, which is much higher than that of the undoped sample of only 82 mAh g−1. The significantly enhanced capacity retention and rate capability are attributed to the more stable spinel structure, higher
ion diffusion coefficient, and lower charge transfer resistance of the Ti-doped spinel. 相似文献
9.
Dan Shao Jiarong He Ying Luo Wei Liu Xiaoyuan Yu Yueping Fang 《Journal of Solid State Electrochemistry》2012,16(6):2047-2053
Nanoporous Li4Ti5O12 (N-LTO) was prepared by sol–gel method using monodisperse polystyrene spheres as a template and followed by calcination process. The as-prepared N-LTO has a spinel structure, large special surface area, and nanoporous structure with the pore average diameter of about 100?nm and wall thickness of 50?nm. Electrochemical experiments show that N-LTO exhibits a high initial discharge capacity of 189?mAh?g?1 at 0.1?C rate cycled between 0.5 and 3.0?V and excellent capacity retention of 170?mAh?g?1 after 100?cycles. EIS and CV analysis show that N-LTO has a higher mobility for Li+ diffusion and a higher exchange current density, indicating an improved electrochemical performance. It is believed that the nanoporous structure has a larger electrode/electrolyte contact area, resulting in better electrochemical properties at high charge/discharge rates. 相似文献
10.
Dr. Anqiang Pan Ting Zhu Hao Bin Wu Prof. Xiong Wen Lou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(2):494-500
Nanosheet‐assembled hierarchical V2O5 hollow microspheres are successfully obtained from V‐glycolate precursor hollow microspheres, which in turn are synthesized by a simple template‐free solvothermal method. The structural evolution of the V‐glycolate hollow microspheres has been studied and explained by the inside‐out Ostwald‐ripening mechanism. The surface morphologies of the hollow microspheres can be controlled by varying the mixture solution and the solvothermal reaction time. After calcination in air, hierarchical V2O5 hollow microspheres with a high surface area of 70 m2 g?1 can be obtained and the structure is well preserved. When evaluated as cathode materials for lithium‐ion batteries, the as‐prepared hierarchical V2O5 hollow spheres deliver a specific discharge capacity of 144 mA h g?1 at a current density of 100 mA g?1, which is very close to the theoretical capacity (147 mA h g?1) for one Li+ insertion per V2O5. In addition, excellent rate capability and cycling stability are observed, suggesting their promising use in lithium‐ion batteries. 相似文献
11.
Guojun Du Dr. Zhaolin Liu Dr. Siok Wei Tay Prof. Xiaogang Liu Prof. Aishui Yu 《化学:亚洲杂志》2014,9(9):2514-2518
Porous microspherical Li4Ti5O12 aggregates (LTO‐PSA) can be successfully prepared by using porous spherical TiO2 as a titanium source and lithium acetate as a lithium source followed by calcinations. The synthesized LTO‐PSA possess outstanding morphology, with nanosized, porous, and spherical distributions, that allow good electrochemical performances, including high reversible capacity, good cycling stability, and impressive rate capacity, to be achieved. The specific capacity of the LTO‐PSA at 30 C is as high as 141 mA h g?1, whereas that of normal Li4Ti5O12 powders prepared by a sol–gel method can only achieve 100 mA h g?1. This improved rate performance can be ascribed to small Li4Ti5O12 nanocrystallites, a three‐dimensional mesoporous structure, and enhanced ionic conductivity. 相似文献
12.
Li Wang Qizhen Xiao Zhaohui Li Gangtie Lei Ping Zhang Lijuan Wu 《Journal of Solid State Electrochemistry》2012,16(10):3307-3313
Porous lithium titanate (Li4Ti5O12) fibers, composed of interconnected nanoparticles, are synthesized by thermally treating electrospun precursor fibers and utilized as an energy storage material for rechargeable lithium-ion batteries. The material is characterized by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, and thermal analysis. Scanning electron microscopy results show that the Li4Ti5O12 fibers calcined at 700?°C have an average diameter of 230?nm. Especially, the individual fiber is composed of nanoparticles with an average diameter of 47.5?nm. Electrochemical properties of the material are evaluated using cyclic voltammetry, galvanostatic cycling, and electrochemical impedance spectroscopy. The results show that as-prepared Li4Ti5O12 exhibits good cycling capacity and rate capability. At the charge–discharge rate of 0.2, 0.5, 1, 2, 10, 20, 40, and 60?C, its discharge capacities are 172.4, 168.2, 163.3, 155.9, 138.7, 123.4, 108.8, and 90.4?mAh?g?1, respectively. After 300 cycles at 20?C, it remained at 120.1?mAh?g?1. The obtained results thus strongly support that the electrospun Li4Ti5O12 fibers could be one of the most promising candidate anode materials for lithium-ion batteries in electric vehicles. 相似文献
13.
A spinel Li4Ti5O12 nanoplatelet/reduced graphite oxide nano-hybrid was successfully synthesized by a two-step microwave-assisted solvothermal reaction and heat treatment. The Li4Ti5O12 in the hybrid could deliver a discharge capacity of 154 mAhg? 1 of Li4Ti5O12 at 1 C-rate, 128 mAhg-1 of Li4Ti5O12 at 50 C-rate and 101 mAhg-1 of Li4Ti5O12 at 100 C-rate. It demonstrated promising potential as an anode material in a Li-ion battery with excellent rate capability and good cycling. 相似文献
14.
Nano-structured spinel Li2Mn4O9 powder was prepared via a combustion method with hydrated lithium acetate (LiAc·2H2O), manganese acetate (MnAc2·4H2O), and oxalic acid (C2H2O4·2H2O) as raw materials, followed by calcination of the precursor at 300 °C. The sample was characterized by X-ray diffraction,
scanning electron microscope, and energy-dispersive X-ray spectroscopy techniques. Electrochemical performance of the nano-Li2Mn4O9 material was studied using cyclic voltammetry, ac impedance, and galvanostatic charge/discharge methods in 2 mol L−1 LiNO3 aqueous electrolyte. The results indicated that the nano-Li2Mn4O9 material exhibited excellent electrochemical performance in terms of specific capacity, cycle life, and charge/discharge
stability, as evidenced by the charge/discharge results. For example, specific capacitance of the single Li2Mn4O9 electrode reached 407 F g−1 at the scan rates of 5 mV s−1. The capacitor, which is composed of activated carbon negative electrode and Li2Mn4O9 positive electrode, also exhibits an excellent cycling performance in potential range of 0–1.6 V and keeps over 98% of the
maximum capacitance even after 4,000 cycles. 相似文献
15.
Yunyan Zhao Shuping Pang Chuanjian Zhang Qinghua Zhang Lin Gu Xinhong Zhou Guicun Li Guanglei Cui 《Journal of Solid State Electrochemistry》2013,17(5):1479-1485
Nitridated mesoporous Li4Ti5O12 spheres were synthesized by a simple ammonia treatment of Li4Ti5O12 derived from mesoporous TiO2 particles and lithium acetate dihydrate via a solid state reaction in the presence of polyethylene glycol 20000. The carbonization of polyethylene glycol could effectively restrict the growth of primary particles, which was favorable for lithium ions diffusing into the nanosized TiO2 lattice during the solid state reaction to form a pure phase Li4Ti5O12. After a subsequent thermal nitridation treatment, a high conductive thin TiO x N y layer was in situ constructed on the surface of the primary nanoparticles. As a result, the nitridated mesoporous Li4Ti5O12 structure, possessing shorter lithium-ion diffusion path and better electrical conductivity, displays significantly improved rate capability. The discharge capacity reaches 138 mAh?g?1 at 10 C rate and 120 mAh?g?1 at 20 C rate in the voltage range of 1–3 V. 相似文献
16.
Li4Ti5O12/reduced graphene oxide (RGO) composites were prepared via a simple strategy. The as-prepared composites present Li4Ti5O12 nanoparticles uniformly immobilized on the RGO sheets. The Li4Ti5O12/RGO composites possess excellent electrochemical properties with good cycle stability and high specific capacities of 154 mAh g− 1 (at 10C) and 149 mAh g− 1 (at 20C), much higher than the results found in other literatures. The superior electrochemical performance of the Li4Ti5O12/RGO composites is attributed to its unique hybrid structure of conductive graphene network with the uniformly dispersed Li4Ti5O12 nanoparticles. 相似文献
17.
Jie Shu 《Journal of Solid State Electrochemistry》2009,13(10):1535-1539
Electrochemical behavior and stability of spinel Li4Ti5O12 are investigated in a broad voltage window (0.0–5.0 V vs. Li/Li+). The voltage profile of the Li4Ti5O12 electrode shows a plateau region at 1.55 V and two sloped regions below 1.55 V when the electrode is cycled between 0.0 and
2.0 V. It is found that Li4Ti5O12 maintains high lithium storage characteristic with the increase of the current density. Moreover, Li4Ti5O12 shows excellent rate performance in 0.0–2.0 V and good cyclic performances in 0.0–4.0 and 1.0–5.0 V. Besides, the crystal
structure is kept when it is cycled between 0.0 and 5.0 V. 相似文献
18.
Shunyi Yang Xianyou Wang Quanqi Chen Xiukang Yang Jiaojiao Li Qiliang Wei 《Journal of Solid State Electrochemistry》2012,16(2):481-490
LiNi1/3Co1/3Mn1/3O2 cathode materials for the application of lithium ion batteries were synthesized by carbonate co-precipitation routine using
different ammonium salt as a complexant. The structures and morphologies of the precursor [Ni1/3Co1/3Mn1/3]CO3 and LiNi1/3Co1/3Mn1/3O2 were investigated through X-ray diffraction, scanning electron microscope, and transmission electron microscopy. The electrochemical
properties of LiNi1/3Co1/3Mn1/3O2 were examined using charge/discharge cycling and cyclic voltammogram tests. The results revealed that the microscopic structures,
particle size distribution, and the morphology properties of the precursor and electrochemical performance of LiNi1/3Co1/3Mn1/3O2 were primarily dependent on the complexant. Among all as-prepared LiNi1/3Co1/3Mn1/3O2 cathode materials, the sample prepared from Na2CO3–NH4HCO3 routine using NH4HCO3 as the complexant showed the smallest irreversible capacity of 19.5 mAh g−1 and highest discharge capacity of 178.4 mAh g−1 at the first cycle as well as stable cycling performance (98.7% of the initial capacity was retained after 50 cycles) at
0.1 C (20 mA g−1) in the voltage range of 2.5–4.4 V vs. Li+/Li. Moreover, it delivered high discharge capacity of over 135 mAh g−1 at 5 C (1,000 mA g−1). 相似文献
19.
S. N. Eliseeva K. A. Vorob’eva E. V. Shkreba R. V. Apraksin V. V. Kondrat’ev 《Russian Journal of Applied Chemistry》2017,90(8):1230-1233
Lithium-ion battery based on LiMn2O4/Li4Ti5O12 materials was assembled for the first time. The cathode and anode of this battery are prepared with the aqueous combined binder poly-3,4-ethylenedioxythiophene: polystyrene sulfonate/carboxymethylcellulose (without polyvinylidene fluoride). The capacity of the LiMn2O4/Li4Ti5O12 battery was found to be 75 mA h g–1 at 0.1 C and 55 mA h g–1 at 1 C. A 95% capacity was retained after 100 charge-discharge cycles. The batteries demonstrated a high Coulombic efficiency close to 100%. Scanning electron microscopy demonstrated that using the conducting binder poly-3,4-ethylenedioxythiophene: polystyrene sulfonate/carboxymethylcellulose provides formation of dense compact layers of electrode materials with good adhesion to the substrate. The electrode structure remains maintained after 100 charge-discharge cycles. 相似文献
20.
Sulfone-based electrolytes have been investigated as electrolytes for lithium-ion cells using high-voltage positive electrodes, such as LiMn2O4 and LiNi0.5Mn1.5O4 spinels, and Li4Ti5O12 spinel as negative electrode. In the presence of imide salt (LiTFSI) and ethyl methyl sulfone or tetramethyl sulfone (TMS) electrolytes, the Li4Ti5O12/LiMn2O4 cell exhibited a specific capacity of 80 mAh g?1 with an excellent capacity retention after 100 cycles. In a cell with high-voltage LiNi0.5Mn1.5O4 positive electrode and 1 M LiPF6 in TMS as electrolyte, the capacity reached 110 mAh g?1 at the C/12 rate. When TMS was blended with ethyl methyl carbonate, the Li4Ti5O12/LiNi0.5Mn1.5O4 cell delivered an initial capacity of 80 mAh g?1 and cycled fairly well for 1000 cycles under 2C rate. The exceptional electrochemical stability of the sulfone electrolytes and their compatibility with the Li4Ti5O12 safer and stable anode were the main reason behind the outstanding electrochemical performance observed with high-potential spinel cathode materials. These electrolytes could be promising alternative electrolytes for high-energy density battery applications such as plug-in hybrid and electric vehicles that require a long cycle life. 相似文献