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Physical Sciences and Mathematics

Cathode material

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Full-Text Articles in Catalysis and Reaction Engineering

Synthesis Of Graphene Wrapped Li-Rich Layered Metal Oxide And Its Electrochemical Performance, Meng-Yan Hou, Ke Wang, Xiao-Li Dong, Yong-Yao Xia Jun 2015

Synthesis Of Graphene Wrapped Li-Rich Layered Metal Oxide And Its Electrochemical Performance, Meng-Yan Hou, Ke Wang, Xiao-Li Dong, Yong-Yao Xia

Journal of Electrochemistry

In present work, lithium-rich layered transition metal oxide (LLO) was synthesized by a co-precipitation method in combination with a solid-state reaction. The graphene wrapped Li-rich layered oxide composite (LLO/Gra) was obtained by sintering the LLO/GO composite at 300 oC for 30 min in an air. The morphologies and the electrochemical performances were characterized by means of SEM, TEM, XRD, XPS, EIS and charge/discharge tests. The results indicated that the LLOe particles were uniformly wrapped with graphene. The resulting material exhibited better rate capability than that of pristine LLO since the wrapped graphene demonstrated the enhanced electronic conductivity. Accordingly, the …


Synthesis Of Namnpo4 By Spraying Drying-High Temperature Sintering And Its Electrochemical Performance, Xiao-Chen Lin, Xiao-Biao Wu, Xu Hou, Yong Yang Dec 2014

Synthesis Of Namnpo4 By Spraying Drying-High Temperature Sintering And Its Electrochemical Performance, Xiao-Chen Lin, Xiao-Biao Wu, Xu Hou, Yong Yang

Journal of Electrochemistry

As a cathode material for sodium ion batteries, NaMnPO4/C nanocomposite is successfully synthesized by the combination of spraying drying and high temperature sintering methods. The crystal structure of the as-synthesized phosphate material is confirmed as the natrophilite NaMnPO4, which possesses orthorhombic symmetry and Pmnb space group. It is shown that the precursors are hollow spherical particles and the obtained product consists of micro-scaled secondary particles, which are composed of NaMnPO4 nanocrystallites (tens of nanometres) and amorphous carbon networks. The ionic and electronic conductivities of NaMnPO4 are both effectively enhanced with the help of this …


Synthesis And Electrochemical Properties Of Lico1-XMgXMno4 And Lico1-XAlXMno4 (X= 0, 0.02, 0.05, 0.1) As Positive Materials For Lithium-Ion Batteries, Mei-Ling You, Qing-Song Tong, Xiu-Hua Li, Min Lin, Xing-Kang Huang, Yong Yang Feb 2014

Synthesis And Electrochemical Properties Of Lico1-XMgXMno4 And Lico1-XAlXMno4 (X= 0, 0.02, 0.05, 0.1) As Positive Materials For Lithium-Ion Batteries, Mei-Ling You, Qing-Song Tong, Xiu-Hua Li, Min Lin, Xing-Kang Huang, Yong Yang

Journal of Electrochemistry

The Al-doped and Mg-doped LiCoMnO4 materials were synthesized through solid-state reaction. The effects of doping amounts of Mg and Al on the initial capacities, discharge plateaus, and cycle performances were investigated. The morphologies and structures of the as-prepared materials were studied by scanning electron microscopy and powder X-ray diffraction. The results indicate that the as-prepared samples were composed of uniform, well-crystallized particles. The pristine LiCoMnO4 possessed an initial capacity of 87.0 mAh·g-1, while LiCo0.98Mg0.02MnO4 and LiCo0.98Al0.02MnO4 delivered 91.3 and 93.6 mAh·g-1, respectively. The proper …


Synthesis And Electrochemical Property Of Li2Fesio4/C Cathode Material By Solid State Method, Jiao-Li Sun, Zhi-Jiao Chen, Yi-Xiao Li, Hu Cheng Dec 2013

Synthesis And Electrochemical Property Of Li2Fesio4/C Cathode Material By Solid State Method, Jiao-Li Sun, Zhi-Jiao Chen, Yi-Xiao Li, Hu Cheng

Journal of Electrochemistry

Li2FeSiO4/C cathode material was synthesized using Li2SiO3 and FeC2O4 as raw materials by solid state method. The structure and morphology of the material were characterized by XRD and SEM. The electrochemical properties of the material were studied by constant-current cyclic testing. The results show that Li2FeSiO4/C has a good electrochemical performance. The first discharge capacity of Li2FeSiO4/C cathode material at 30oC reached 167 mAhg-1 when cycled at 10 mAg-1 between 1.5 and 4.8 V.


Electrochemical Performance Of Lifepo4/C Synthesized Via Aqueous Solution-Evaporation Route, Ning-Yu Gu, Xing-Hua He, Yang Li Apr 2013

Electrochemical Performance Of Lifepo4/C Synthesized Via Aqueous Solution-Evaporation Route, Ning-Yu Gu, Xing-Hua He, Yang Li

Journal of Electrochemistry

The LiFePO4/C samples have been synthesized via an aqueous solution-evaporation route with LiH2PO4, FeC2O4.2H2O as raw materials and citric acid as a carbon source. X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used to analyze structure and morphology of the samples. The electrochemical performances of the LiFePO4/C cathodes were characterized by charge/discharge cures and electrochemical impedance spectroscopy (EIS). The results show that the LiFePO4/C sample, calcined at 700 °C and contained 3.03% (by mass) carbon, exhibited a highly pure …


Synthesis And Electrochemical Properties Of High-Capacity Cathode Material 0.08lico0.75Al0.25O2-0.92linio2, Ru-Ying Wang, Tian Qiu, Chong Mao, Wen-Sheng Yang Aug 2012

Synthesis And Electrochemical Properties Of High-Capacity Cathode Material 0.08lico0.75Al0.25O2-0.92linio2, Ru-Ying Wang, Tian Qiu, Chong Mao, Wen-Sheng Yang

Journal of Electrochemistry

CoAl-LDH or Co(OH)2 coated spherical Ni(OH)2 precursors were obtained via a co-precipitation method at a constant pH. The mixtures of the precursors and LiOH.H2O were annealed at high temperature in O2 atmosphere, and then the cathode materials of 0.08LiCo0.75Al0.25O2-0.92LiNiO2, 0.08LiCoO2-0.92LiNiO2 and LiNiO2 were synthesized. Effects of the coating layer were also studied. The results showed that the 0.08LiCo0.75Al0.25O2-0.92LiNiO2 material possessed the best rate and cycle life performance. The discharging capacities at 0.1C, 0.5C and 3C were …


Synthesis Of Limnpo4/C Used As Cathode Material For Lithium Ion Batteries, Xin Yang, Xue-Wu Liu, Gui-Chang Liu, Zhi-Cong Shi, Xin Li, Guo-Hua Chen Aug 2011

Synthesis Of Limnpo4/C Used As Cathode Material For Lithium Ion Batteries, Xin Yang, Xue-Wu Liu, Gui-Chang Liu, Zhi-Cong Shi, Xin Li, Guo-Hua Chen

Journal of Electrochemistry

The LiMnPO4/C composites were prepared using a solid-state reaction with addition of the resorcinol formaldehyde resin as the carbon source. The effects of reaction temperature and time on the crystal structure, morphology and electrochemical properties of the LiMnPO4/C composites were investigated. The results show that the best performance was achieved with the LiMnPO4/C composites synthesized at 600 oC for 12 h which had the particle sizes about 100~200 nm. The initial discharge capacities were 121.6 mAh?g-1 at 0.02C, 110 mAh?g-1 at 0.1C and more than 60 mAh?g-1 at 1C. An overall reversible capacity of 110 mAh?g-1 had been retained after …


The Sol-Gel Synthesis And Electrochemical Performance Of Li_3v_2(Po_4)_3/C Cathode Material For Lithium Ion Battery, Li-Ying Liu, Lian Chen, Hai-Yan Zhang, Yu-Chun Zhai Nov 2010

The Sol-Gel Synthesis And Electrochemical Performance Of Li_3v_2(Po_4)_3/C Cathode Material For Lithium Ion Battery, Li-Ying Liu, Lian Chen, Hai-Yan Zhang, Yu-Chun Zhai

Journal of Electrochemistry

Li3V2(PO4)3/C was synthesized by sol-gel method with citric acid as chelate and C sources.Physical and electrochemical performances of as-prepared materials were characterized through XRD,SEM and galvanostatic charge-discharge tests,etc.The results showed that products produced by calcining at 800 ℃ for 12 h had a single phase crystal structure and relatively small particle sizes with uniform distribution.At 0.1 C,0.5 C and 1 C,the initial specific discharge capacities were 153.0,143.1 and 130.6 mAh·g-1,respectively,and capacity efficiencies were 93.1%,85.4% and 77.3% after 50 cycles,respectively.Charge efficiencies were all above 80% and discharge voltages were higher.


Synthesis And Electrochemical Properties Of Li_3v_2(Po_4)_3/C Cathode Materials For Lithium Ion Battery, Li-Ying Liu, Hai-Yan Zhang, Lian Chen, Yu-Chun Zhai May 2010

Synthesis And Electrochemical Properties Of Li_3v_2(Po_4)_3/C Cathode Materials For Lithium Ion Battery, Li-Ying Liu, Hai-Yan Zhang, Lian Chen, Yu-Chun Zhai

Journal of Electrochemistry

Cathode material Li3V2( PO4) 3 /C for Lithium-ion battery was synthesized by combination of ball milling and baking. Physical and electrochemical performances of as-prepared materials were characterized through XRD,EIS and galvanostatic cell cycling. The results show that the products were monoclinic Li3 V2 ( PO4) 3 with well-developed crystal structure. At 0. 1C,0. 25C and 0. 5C,the initial discharge capacities were 150. 6,134. 1 and 107. 1 mAh·g-1 ,respectively. Capacity retention rates were 87. 3% after 130 cycles at 0. 25C and 87. 2% after 105 cycles at 0. 5C. Charge-discharge efficiencies were all above 80% and the average discharge …


Synthesis Of Agv_3o_8 As High-Capacity Of Cathode Materials For Lithium Secondary Batteries Via A Soft Chemistry Technique, Xiao-Yu Cao, Tao Li, Ling-Ling Xie, Xiang-Yang Yan, Chi-Wei Wang May 2008

Synthesis Of Agv_3o_8 As High-Capacity Of Cathode Materials For Lithium Secondary Batteries Via A Soft Chemistry Technique, Xiao-Yu Cao, Tao Li, Ling-Ling Xie, Xiang-Yang Yan, Chi-Wei Wang

Journal of Electrochemistry

The layered cathode material of AgV3O8 has been prepared for the lithium secondary batteries via the soft chemistry technique. The so-synthesized powders were characterized by XRD(powder X-ray diffraction),SEM(scanning electron microscope) and LPSA(laser particle size analysis).The electrochemical property was investigated by the galvanostatic discharge-charge technique.The results indicated that the particale sizes of AgV3O8 prepared were small in the distribution of narrow range,which leads to high discharge capacity.Among them,the material synthesized at 400 ℃ displayed the first discharge capacity of 760.5 mAh/g.


Electrochemical Performance Of Li_(1-X)M_Xfepo_4 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)M_Xfepo_4 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 Nov 2006

The Synthesis,Structure And Electrochemical Performances Of Lithium Iron Phosphate, Hui Xie

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 LiFePO_(4).The sample synthesized under 600℃ showed the best charge-discharge performances with the first specific discharge capacity of(128.8) mAh/g and the 15~(th) specific discharge capacity of 129.1 mAh/g at 0.1C rate,each charge-discharge cycling efficiency being 99.7%.Also the sample showed good …


Structure And Electrochemical Characteristics Of Lifepo_4 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 Lifepo_4 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 LiFePO_(4) 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 LiFePO_(4) by using polyacrylate-pyrolysis-reduction method.


Calcined Temperatures Influence On Synthesis And Electrochemistry Charactarization Of Li[Ni_(0.475)Mn_(0.475)Co_(0.05)]O_(2) For Li-Ion Batteries, Li-Qin Wang, Li-Fang Jiao, Hua-Tang Yuan Aug 2006

Calcined Temperatures Influence On Synthesis And Electrochemistry Charactarization Of Li[Ni_(0.475)Mn_(0.475)Co_(0.05)]O_(2) For Li-Ion Batteries, Li-Qin Wang, Li-Fang Jiao, Hua-Tang Yuan

Journal of Electrochemistry

Layered Li[Ni_(0.475)Mn_(0.475)Co_(0.05)]O_(2) 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.


The Influence Of Pva As Disperser On Lifepo_(4) Synthesized By Hydrothermal Reaction, Hui-Lin Li, Hui Zhan Aug 2006

The Influence Of Pva As Disperser On Lifepo_(4) Synthesized By Hydrothermal Reaction, Hui-Lin Li, Hui Zhan

Journal of Electrochemistry

LiFePO_(4) 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 LiFePO_(4)material was discussed in detail.


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 Aug 2002

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.


Synthesis Of Limn_2o_(4-Δ) Cl_Δ 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 Limn_2o_(4-Δ) Cl_Δ Cathode Material By Like-Sol-Gel Methode, Zhao Yong Chen, Yi He, Xing Quan Liu, Zhi-Jie Li, Zuo-Long Yu

Journal of Electrochemistry

LiMn 2O 4 δ Cl δ was synthesized by like sol gel methode, with calculated LiOH.H 2O, Mn(No 3) 2.6H 2O and LiCl.H 2O, and made electrochemical test with these compounds as positive materials. Result demostrated that LiMn 2O 4 δ Cl δ cathode material has exellent stability and nearly no capacity loss after reaching stability.