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Full-Text Articles in Physical 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 Feb 2008

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 …


Electrochemical Performance Of Li(1-X)MXFepo4 Cathode Materials Synthesized By Polymer Pyrolysis Route, Ting Li, Jiang-Feng Qian, Yu-Liang Cao, Han-Xi Yang, Xin-Ping Ai May 2007

Electrochemical Performance Of Li(1-X)MXFepo4 Cathode Materials Synthesized By Polymer Pyrolysis Route, Ting Li, Jiang-Feng Qian, Yu-Liang Cao, Han-Xi Yang, Xin-Ping Ai

Journal of Electrochemistry

Olivine Li1-xMxFePO4(M=Cr3+, Mg2+, Mn2+, Ni2+) were synthesized by a polyacrylates-pyrolysis route. The structural and electrochemical properties of the as-synthesized cathode materials were investigated by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), and electrochemical charge/discharge cycling. The results indicate that the metallic ions doped at low concentration do not affect the crystalline structure of the material, but considerably improve the rate capability and cycle performance of LiFePO4 at high rate.


The Synthesis, Structure And Electrochemical Performances Of Lithium Iron Phosphate, Hui Xie, Zhen-Tao Zhou Nov 2006

The Synthesis, Structure And Electrochemical Performances Of Lithium Iron Phosphate, Hui Xie, Zhen-Tao Zhou

Journal of Electrochemistry

The lithium iron phosphate cathode materials were synthesized by solid-state reaction combined high-rate ball milling under the temperature ranging from 400 ℃ to 700 ℃.The crystalline structure, morphology of particles, and electrochemical performance of the sample were investigated by X-ray diffraction, scanning electron microscopy and charge-discharge test. The results showed that the sintering temperature had great influences on the crystal structure, morphology and electrochemical performances of LiFePO4. The sample synthesized under 600℃ showed the best charge-discharge performances with the first specific discharge capacity of(128.8) mAh/g and the 15th specific discharge capacity of 129.1 mAh/g at 0.1C rate, …


Structure And Electrochemical Characteristics Of Lifepo4 Prepared By The Polyacrylates-Pyrolysis-Reduction Method For Li-Ion Batteries, Li-Hong Yu, Yu-Liang Cao, Xiao-Fei Zhang, Han-Xi Yang, Xin-Ping Ai Nov 2006

Structure And Electrochemical Characteristics Of Lifepo4 Prepared By The Polyacrylates-Pyrolysis-Reduction Method For Li-Ion Batteries, Li-Hong Yu, Yu-Liang Cao, Xiao-Fei Zhang, Han-Xi Yang, Xin-Ping Ai

Journal of Electrochemistry

The cathode material of olivine LiFePO4 was prepared by a novel method of polyacrylate-pyrolysis-reduction.XRD demonstrates that the material have the olivine structure.SEM photo shows an average particle-size of about 100 nm with a well distribution.Electrochemical test of cycling at a constant current reveals the discharge capacity of 138 mAh/g and a good cycling stability.It is a novel practicable technology to prepare LiFePO4 by using polyacrylate-pyrolysis-reduction method.


Effects On The Structure And Electrochemical Performance Of Lifepo4 By Zr4+ Doping, Yan-Li Ruan, Zhi-Yuan Tang Aug 2006

Effects On The Structure And Electrochemical Performance Of Lifepo4 By Zr4+ Doping, Yan-Li Ruan, Zhi-Yuan Tang

Journal of Electrochemistry

Stoichiometric Zr-doped lithium iron phosphate(LiFePO4)) cathode material was synthesized by a solid-state reaction in an inert atmosphere. The effects of doping content on the physical and electrochemical properties of as-synthesized cathode materials were investigated.The samples were characterized by powder X-ray diffraction(XRD), and their electrochemical performance was systematically measured by impedance response and constant current charge/discharge cycling tests. The results indicate that the low concentration Zr4+ doping does not affect the structure of the material but considerably improves its kinetics in terms of capacity delivery and cycle performance. At 0.1C discharging rate,the reversible specific capacities of the Li …


The Influence Of Pva As Disperser On Lifepo4 Synthesized By Hydrothermal Reaction, Hui-Lin Li, Hui Zhan, Yu-Hong Zhou Aug 2006

The Influence Of Pva As Disperser On Lifepo4 Synthesized By Hydrothermal Reaction, Hui-Lin Li, Hui Zhan, Yu-Hong Zhou

Journal of Electrochemistry

LiFePO4 was synthesized by means of hydrothermal reaction,in which PVA acts as disperser and glucose as carbon source. The samples were characterized by X-ray diffraction, scanning electron microscopy and electrochemical measurement. SEM results show that the sample is homogeneously composed of grains with a particle size of ca.200nm. In the charge/discharge test, the products exhibited a 3.45V discharge voltage plateau and a maximum specific capacity of 140mAh/g. After 40 cycles, its capacity only declined by 2.1%. Besides these, the mechanism for the influence of the particle size and carbon coating on the electrochemical property of LiFePO4 material was …


Calcined Temperatures Influence On Synthesis And Electrochemistry Charactarization Of Li[Ni0.475Mn0.475Co0.05]O2 For Li-Ion Batteries, Li-Qin Wang, Li-Fang Jiao, Hua-Tang Yuan, Yong-Mei Wang Aug 2006

Calcined Temperatures Influence On Synthesis And Electrochemistry Charactarization Of Li[Ni0.475Mn0.475Co0.05]O2 For Li-Ion Batteries, Li-Qin Wang, Li-Fang Jiao, Hua-Tang Yuan, Yong-Mei Wang

Journal of Electrochemistry

Layered Li[Ni0.475Mn0.475Co0.05]O2 materials have been prepared by a solid-state pyrolysis method.Experiments of XRD,SEM,cyclic voltammetry and charge/discharge cycling were carried out.It can be learned that when calclined at 800 ℃,the sample showed the highest first discharge capacity of 178.8 mAh·g-1 at a current density of 20 mA/g in the voltage range 2.3~4.6 V


LicoXNi1-XO2 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 Nov 2004

LicoXNi1-XO2 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 LiCoxNi1-xO2 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 CoxNi1- x(OH)2.Different compositional precursors could be conveniently prepared by changing electrolytic current. The LiCo0.3Ni0.7O2 cathode prepared by this method was found favorable charge-discharge and cycle properties. For the LiCo0.3Ni0.7O2 cathode material, …


Synthesis And Characterization Of Lini0.8-XAlXCo0.2O2 As Cathodes For Lithium-Ion Batteries, Jun Zhang, Zhong-Kao Jin, Qing-He Yang, Qing-Mei Song, Xiao-Hua Ma, Xiang-Fu Zong Aug 2002

Synthesis And Characterization Of Lini0.8-XAlXCo0.2O2 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 LiNi0.8-xAlxCo0.2O2 (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 LiNi0.71Al0.09Co0.2O2 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, …


Synthesis Of Limn2O4-ΔClΔ Cathode Material By Like-Sol-Gel Methode, Zhao-Yong Chen, Yi He, Xing-Quan Liu, Zhi-Jie Li, Zuo-Long Yu Feb 2001

Synthesis Of Limn2O4-ΔClΔ Cathode Material By Like-Sol-Gel Methode, Zhao-Yong Chen, Yi He, Xing-Quan Liu, Zhi-Jie Li, Zuo-Long Yu

Journal of Electrochemistry

LiMn2O4-δClδ was synthesized by like sol gel methode, with calculated LiOH·H2O, Mn(No3)2⋅6H2O and LiCl·H2O, and made electrochemical test with these compounds as positive materials. Result demostrated that LiMn2O4-δClδ cathode material has exellent stability and nearly no capacity loss after reaching stability.


Study On Ni-Co-S-Mo Alloys New Cathode Material For Aquous Electrolysis, Yuan-Shou Xie, Quan-Feng Liu Nov 1998

Study On Ni-Co-S-Mo Alloys New Cathode Material For Aquous Electrolysis, Yuan-Shou Xie, Quan-Feng Liu

Journal of Electrochemistry

The parameters of electrodeposion of Ni-Co-S-Mo alloy were studied. The experimental results indicate that the electrodeposition alloy shows high catalytic activity for hydrogen evolution reaction, as well as better mechanical strength and higher chemical stability. The mechanism of catalytic hydrogen evolution reaction on this type of alloy electrode was also investigated by means of polarization curve and cyclic voltametry.