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Full-Text Articles in Chemistry
Preparation And Electrochemical Performance Of Ordered Mesoporous Titanium Phosphate As Cathode Material For Li-Ion Battery, Qiong Wang, Attia Adel, Zhi-Cong Shi, Yong Yang
Preparation And Electrochemical Performance Of Ordered Mesoporous Titanium Phosphate As Cathode Material For Li-Ion Battery, Qiong Wang, Attia Adel, Zhi-Cong Shi, Yong Yang
Journal of Electrochemistry
Ordered porous titanium phosphate materials were prepared by using the surfactant template combined with the sol-gel method.The samples were characterized by small angle X-ray diffraction(SA-XRD) method,N2 adsorption/desorption techniques,high resolution transmission electron microscopy(HRTEM) and element analysis.It is found that the calcination temperature is a big influence on the porous structure,and electrochemical performance of the titanium phosphate materials.,and the mesoporous titanium phosphate showed good performance in the electrochemical test,the first discharge capacity is 94 mAh/g at the current density of 150 mA/g.On the other hand,the no porous material with a low capacity of 37 mAh/g under the same charge-discharge condition.
Cu Doping Lifepo_4 And Its Electrochemical Performance, Ming-Sen Zheng, Shan-Ke Liu, Shi-Gang Sun, Quan-Feng Dong
Cu Doping Lifepo_4 And Its Electrochemical Performance, Ming-Sen Zheng, Shan-Ke Liu, Shi-Gang Sun, Quan-Feng Dong
Journal of Electrochemistry
LiFePO4 and LiFePO4 doped with Cu2+ ions were synthesized by solid-state reactions.The structure of LiFePO4 and the Fe valence were analyzed by the XRD(X-ray diffraction) and XPS(X-ray photoelectron spectroscopy) respectively.The Cu doping position in LiFePO4 is discussed.It has found that the volume of LiFePO4 by doping Cu2+ ions is reduced.The minim Cu2+ ions doping does not almost change the binding energy of Fe2p1/2 in LiFePO4.According to the experiment results,we conclude that most of the Cu2+ ions substitute the Fe2+ ions in LiFePO4 when a small amount of Cu2+ ions doping is occurred.
Preparation And Properties Of High Capacity Lifepo_4, Jun Li, Gui-Tang Lai, Hui-Min Huang, Da-Guang Li, Xin-De Xia
Preparation And Properties Of High Capacity Lifepo_4, Jun Li, Gui-Tang Lai, Hui-Min Huang, Da-Guang Li, Xin-De Xia
Journal of Electrochemistry
Carbon-doped LiFePO4/C and pure phase LiFePO4 cathode materials were prepared by liquid-state precipitation reaction.The results of XRD,SEM,elemental analysis,FTIR and A.C.impedance tests show that the samples have had olivine structure and a 3.4V discharge platform.The tapped density of LiFePO4/C sample could reach 1.46g/cm3,the initiate discharge capacity is 144.6mAh/g at 0.1C,which remained capacity is 93.2% after 20 cycles.The first discharge capacity is 133.5mAh/g at 1C and the capacity decreased 8.76% after 20 cycles.
Studies On Synthesis And Electrochemical Performance Of Li_(X)Ni_(1/3)Mn_(1/3)Co_(1/3)O_(2) As Cathode Material For Lithium Ion Batteries, Xiao-Jian Guo, Jie Li, Yi-Xiao Li, Yong Yang
Studies On Synthesis And Electrochemical Performance Of Li_(X)Ni_(1/3)Mn_(1/3)Co_(1/3)O_(2) As Cathode Material For Lithium Ion Batteries, Xiao-Jian Guo, Jie Li, Yi-Xiao Li, Yong Yang
Journal of Electrochemistry
A series of LiNi_(1/3)Mn_(1/3)Co_(1/3)O_(2) were synthesized by a combined hydroxides coprecipitation and calcination method.Effects of synthesizing temperature of coprecipitations and the Li∶M ratios on structure and electrochemical performance of the materials were studied.The results showed that materials synthesized with coprecipitation at room temperature(~20 ~(o)C) delivered the best electrochemical performance.Another series of cathode materials Li_(x)Ni_(1/3)Mn_(1/3)Co_(1/3)O_(2) with different Li∶M ratios were synthesized with this method.The results showed that sintering at high temperature could cause loss of LiOH,thus more LiOH should be added.It is demonstrated that Li_(1.08)Ni_(1/3)Mn_(1/3)Co_(1/3)O_(2) had the best electrochemical performance.
Structure And Properties Of Electrodeposited Sn-Co Alloy Electrodes As Anode Material For Lithium-Ion Secondary Batteries, Hong-Hong Jiang, Ling Huang
Structure And Properties Of Electrodeposited Sn-Co Alloy Electrodes As Anode Material For Lithium-Ion Secondary Batteries, Hong-Hong Jiang, Ling Huang
Journal of Electrochemistry
The Sn-Co alloy deposits were prepared by electroplating.The structure and electrochemical performance of the electroplated Sn-Co alloys have been investigated in detail.Experimental results show that the porous Sn-Co alloy film exhibits hexagonal solid solution,with Sn as the solvent, Co as the solute.The texture of the Sn-Co alloy coating exhibits(110) preferred orientation.Electrochemical tests show that the porous Sn-Co alloy coating electrodes can deliver a discharge capacity of 643mAh/g in the first cycle.At the 20~(h) cycle the charge was 461mAh/g.At initial charge curve the irreversible capacity is probably associated to a combination of processes,which may include the reduction of small amount of …
Lico_(X)Ni_(1-X)O_2 Cathode Materials Prepared By Electrolysis Of Co And Ni, Jin-Ping Wei, Xin Sun, Xiao-Yu Wang, Xi-Kui Bian, Jin-Ling Zhai, Yan-Jie Yan-Jie
Lico_(X)Ni_(1-X)O_2 Cathode Materials Prepared By Electrolysis Of Co And Ni, Jin-Ping Wei, Xin Sun, Xiao-Yu Wang, Xi-Kui Bian, Jin-Ling Zhai, Yan-Jie Yan-Jie
Journal of Electrochemistry
A new electrolytic method was developed to prepare LiCo_(x)Ni_(1-x)O_2 as a cathode material of lithium-ion battery. Contrary to the traditional method, electrolytic method is a potential method with simple process to industrialization and no pollution. Metal cobalt and nickel were electrolysed in parallel to prepare the precursor of Co_( x )Ni_(1- x )(OH)_2.Different compositional precursors could be conveniently prepared by changing electrolytic current. The LiCo_(0.3)Ni_(0.7)O_2 cathode prepared by this method was found favorable charge-discharge and cycle properties. For the LiCo_(0.3)Ni_(0.7)O_(2 )cathode material, the discharge capacities in the 1st and 50th cycles were 163 mAh/g and 140 mAh/g with charge retention …
Lithium Intercalation Performance Of P-Doped Phenolic Resin Pyrolysis Carbon, Bao-Hua Li, Kai-Xi Li, Yonggen Lv, Chun-Xiang Lv, Dong Wu, Li-Cheng Ling
Lithium Intercalation Performance Of P-Doped Phenolic Resin Pyrolysis Carbon, Bao-Hua Li, Kai-Xi Li, Yonggen Lv, Chun-Xiang Lv, Dong Wu, Li-Cheng Ling
Journal of Electrochemistry
Phosphorus-doped phenolic resin carbon was prepared by low temperature(700 ℃)pyrolysis of thermoplastic phenolic resin containing different amounts of phosphorus pentoxide after curing. X-ray diffraction pattern and the constang-current charge-discharge properties of phenolic resin carbon were studied. The results showed that the phenolic resin carbon microstructure became out of order with increasing of content phosphorus pentoxide,otherwise,the first discharge reversible capacities increased firstly and then decreased. The first discharge reversible capacity of phenolic resin carbon containing 9wt% phosphorus pentoxide was 528 mA·h·g -1 which was higher than that of non-phosphorus doped phenolic resin carbon(230 mA·h·g -1 ) did.
Synthesis And Characterization Of Lini_(0.8-X)Al_Xco_(0.2)O_2 As Cathodes For Lithium-Ion Batteries, Jun Zhang, Zhong-Kao Jin, Qing-He Yang, Qing-Mei Song, Xiao-Hua Ma, Xiang-Fu Zong
Synthesis And Characterization Of Lini_(0.8-X)Al_Xco_(0.2)O_2 As Cathodes For Lithium-Ion Batteries, Jun Zhang, Zhong-Kao Jin, Qing-He Yang, Qing-Mei Song, Xiao-Hua Ma, Xiang-Fu Zong
Journal of Electrochemistry
Single_phase solid solution of LiNi 0.8- x Al x Co 0.2 O 2 (0≤ x <0.1)had been synthesized and characterized by X_ray diffraction(XRD) and scanning electron microscopy (SEM). Their electrochemical performance was examined by charge_discharge cycling.The LiNi 0.71 Al 0.09 Co 0.2 O 2 compound showed a discharge capacity of 152 mAh/g after 20 cycles that corresponds to 97.4% capacity retention. The beneficial effect of co_doping with Al and Co elements was corro_borated by slow scanning cyclic voltammograms(SSCV),electrochemical impedance spectrum(EIS)and differential scanning calorimetry(DSC) data on charged cathodes. These results show that the 2D_character of the crystal lattice was stabilized by co_doping with Al and Co, the phase transitions that occur during deintercalation or intercalation of Li_ions were significantly suppressed,and thermal stability in the charged state was also improved.
The Influence Of Synthesis Conditions On The Electrochemical Properties Of Spinel Limn_2o_4, Jun Feng Xu, Zhi Yu Jiang
The Influence Of Synthesis Conditions On The Electrochemical Properties Of Spinel Limn_2o_4, Jun Feng Xu, Zhi Yu Jiang
Journal of Electrochemistry
The electrochemical properties of spine LiMn 2O 4 synthesized via a solid state reaction were investigated. Electrolysis MnO 2(EMD), Li 2CO 3,LiOH and LiNO 3 were used as the initial materials. It was found that the electrochemical properties of LiMn 2O 4 were strongly influenced by the synthesis conditions. The LiMn 2O 4 samples prepared via the reaction of EMD and LiNO 3 showed the best properties for a lithium ion intercalation reaction. The procedure includes two steps: pretreatment at 280 ℃ for 6 hours to initiate the permeation of melting LiNO 3 into the micropores of EMD particles, followed …
Preparation And Properties Of Separator For Lithium-Ion Battery, Xu-Mei Ren, Feng Wu, Chuan Wu, Han-Jun Li, Xue-Jie Huang
Preparation And Properties Of Separator For Lithium-Ion Battery, Xu-Mei Ren, Feng Wu, Chuan Wu, Han-Jun Li, Xue-Jie Huang
Journal of Electrochemistry
Lithium_ion batteries are well adapted to the new multimedia applications. PP/PE based microporous film is commonly used as separator in commercial lithium ion batteries. Here we report a microporous film which is superior to the commercial available separator. The microporous PVDF polymer separators were prepared by the phase inversion process. The pore size of the separator is 7 μm, and it's porosity is 75%. The membrane in LiPF 6 EC/DEC showed high ionic conductivity (above 10 -3 S/cm at room temperature), and good mechanical properties (10 3 kg/cm 2). The half_cells consisted of Li/PVDF separator/MCMB showed excellent cycling characteristics …
Technical Investigaton Of Thin-Film Plasticizing Lithium Ion Battery, Xin-Ping Ai, Xin-Lin Hong, Quan-Feng Dong, Sheng-Xian Li, Han-Xi Yang
Technical Investigaton Of Thin-Film Plasticizing Lithium Ion Battery, Xin-Ping Ai, Xin-Lin Hong, Quan-Feng Dong, Sheng-Xian Li, Han-Xi Yang
Journal of Electrochemistry
A number of polymer materials as candidates of host matrix of plastic polymer electrolyte were examined and techniques for preparation of thin_film electrolyte were reported. The results showed that the polymer electrolyte prepared with P(VDF_HFP) copolymer as host matrix and DBP as plasticizer exhibit the satisfactory mechanical strength and ionic conductivity. In comprison with liquid electrolyte systems, thin_film lithium ion battery has almost similar charge_discharge capacity and cycleability. The manufacture methods and the technical factors in making plasticizing lithium ion battery were also described in details.
Investigations Of Lithium Ion Battery Electrolyte Solution, Jing-Li Han, Qing-Guo Liu
Investigations Of Lithium Ion Battery Electrolyte Solution, Jing-Li Han, Qing-Guo Liu
Journal of Electrochemistry
Synthesis and electrochemical investigations of ｛LiB[(SO 3)C 6H 3(O)(COO)]OC 6H 5｝in EC/DMC or DMSO/PC mixtures are presented.
Structural And Electrochemical Studies On Todorokite/Vernadite As Cathodes For Rechargeable Lithium Ion Batteries, Wei Chu, Deyao Liu, Jinkua You, Yong Yang, Zugeng Lin
Structural And Electrochemical Studies On Todorokite/Vernadite As Cathodes For Rechargeable Lithium Ion Batteries, Wei Chu, Deyao Liu, Jinkua You, Yong Yang, Zugeng Lin
Journal of Electrochemistry
XRD,TEM,ICP,low scan_rate CV and charge/discharge tests were carried out for the studies on the structural and electrochemical behavior of a prepared 3 V manganese oxide cathode for rechargeable lithium ion batteries.XRD analysis revealed that the cathode sample is mainly composed of tunneled Todorokite and layered Vernadite.TEM investigation confirmed that the morphology of the sample is a laminated construction with approximate 10nm layer space.The reversibility of Li + removal/intercalation and structural stability of this sample framework to lithium insertion are good in CV and charge/discharge tests. The discharge capacities were found to be about 129mAh/g obtained on first 30 cycles and …
A Preliminary Study Of The Synthesis Of Tin Based Amorphous Material And Its Behavior On Lithium Intercalation, Li Liu, Hanxi Yang, Jutang Sun, Xingping Ai
A Preliminary Study Of The Synthesis Of Tin Based Amorphous Material And Its Behavior On Lithium Intercalation, Li Liu, Hanxi Yang, Jutang Sun, Xingping Ai
Journal of Electrochemistry
An amorphous lithium inserting anode material based on Tin oxide glass was synthesized by salification in solution and its properties on lithium intercalation was investigated by X ray diffraction(XRD), microelectrode voltammetry and charge discharge measurements. The results have shown that this kind of material has considerable electrochemical reversibility toward lithium intercalation deintercalation. The available discharge capacity of the material reaches 430 mA·h/g with charge_discharge efficiency over 90%, showing a great potential for practical use.
Surface Modifications Of Carbon Materials Used As Anode Of Lithium Ion Battery Ⅲ. Improvement Of Artificially Imposed Solid Electrolyte Film On Cell Performance, Shuhua Ma, Xiabin Jing, Fosong Wang
Surface Modifications Of Carbon Materials Used As Anode Of Lithium Ion Battery Ⅲ. Improvement Of Artificially Imposed Solid Electrolyte Film On Cell Performance, Shuhua Ma, Xiabin Jing, Fosong Wang
Journal of Electrochemistry
The improving effect of solid electrolyte film artificially imposed on carbon electrode was investigated. The result showed that both the charge/discharge capacity and first charge/discharge efficiency, to a certain extent, were enhanced, and the result also suggested the effectiveness of the substitution of the artificially imposed solid electrolyte film for the inherent passivating film which was formed on the surface of the carbon electrode while inserted in the electrolyte during charging or discharging. The Scanning Electron Microscope result displayed the compact and well defined morphology of the artificially imposed crystalline film.
Surface Modifications Of Carbon Materials Used As Anode Of Lithium Ion Batteryⅱ.The Carbon Material With Core Shell Structure And Its Positive Effect On Cell Performance Of Graphite Anode, Shuhua Ma, Hanju Guo, Ji Li, Hongze Liang, Xiabin Jing, Fosong Wang
Surface Modifications Of Carbon Materials Used As Anode Of Lithium Ion Batteryⅱ.The Carbon Material With Core Shell Structure And Its Positive Effect On Cell Performance Of Graphite Anode, Shuhua Ma, Hanju Guo, Ji Li, Hongze Liang, Xiabin Jing, Fosong Wang
Journal of Electrochemistry
The carbon powders and film electrode with core shell structure were prepared by carbonization in gas state with using refined coal as shell material and Artificial Graphite and Mesocarbon Microbeads (2 800 ℃) graphite as core material. Galvanostatic charge/discharge measurement showed that both steady charge/discharge capacity and first charge/discharge efficiency were improved. Cyclic voltammetry indicated that the peak at about 0.7 V vs. Li +/Li characteristic of decomposition of electrolyte got weakened, and a more compact film was formed. X ray diffraction measurement suggested the existence of amorphous carbon shell on the carbon powders and carbon film.
Surface Modifications Of Carbon Materials Used As Anode Of Lithium Ion Battery Ⅰ.Influences Of Oxidation And Reduction Pretreatment On Anode Performance, Shuhua Ma, Hanju Guo, Ji Li, Hongze Liang, Xiabin Jing, Fosong Wang
Surface Modifications Of Carbon Materials Used As Anode Of Lithium Ion Battery Ⅰ.Influences Of Oxidation And Reduction Pretreatment On Anode Performance, Shuhua Ma, Hanju Guo, Ji Li, Hongze Liang, Xiabin Jing, Fosong Wang
Journal of Electrochemistry
The influences of the trace oxygen containing functional groups on surface of carbon material on cell performance of carbon anode for lithium ion batteries were studied by means of the pretreament in various oxidant/reductant systems.The results showed that the rich oxygen containing functional groups impaired the cell performance of carbon material anode,and the reduction of these groups in quantity and oxidation degree can increase charge/discharge capacity and improve first charge/discharge efficiency.The reason was also discussed in the light of effects of surface organic groups on decomposition reactivity of electrolyte and formation process of surface passivating film.
Progress In R&D Of Lithium Rechargeable Batteries In China, Jiqiang Wang
Progress In R&D Of Lithium Rechargeable Batteries In China, Jiqiang Wang
Journal of Electrochemistry
No abstract provided.