LiMn2O4 Powders Prepared by Solution Combustion Synthesis in Ethanol and Water Systems

2010 ◽  
Vol 160-162 ◽  
pp. 554-557
Author(s):  
Gui Yang Liu ◽  
Jun Ming Guo ◽  
Yan Nan Li ◽  
Bao Sen Wang
Keyword(s):  
Electrochemical Performance ◽  
Combustion Synthesis ◽  
Raw Materials ◽  
Solution Combustion Synthesis ◽  
Xrd Analysis ◽  
Manganese Acetate ◽  
X Ray Diffraction ◽  
Solution Combustion ◽  
Voltage Range ◽  
Ethanol System

Spinel LiMn2O4 powders have been prepared at 500 for 5h by solution combustion synthesis in water or ethanol system, using lithium and manganese acetate as raw materials and no fuels. The structure and morphology of the products have been analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The electrochemical performance has been charged or discharged in coin-type battery. XRD analysis indicates that the purity and crystallinity of the product prepared in ethanol are much better than these of the product prepared in water. SEM investigation indicates that the particles of the product prepared in ethanol are smaller and more dispersed than these of the products prepared in water. The product prepared in ethanol also exhibits better electrochemical performance than that of the product prepared in water. The initial discharge capacity of the product prepared in ethanol is 120mAh/g, and remains 110mAh/g after 20 cycles, at a current density of 50mA/g and in the voltage range of 3.2-4.35V.

Flameless Solution Combustion Synthesis of Al3+ Doped LiMn2O4

2011 ◽  
Vol 186 ◽  
pp. 7-10 ◽  
Author(s):  
Gui Yang Liu ◽  
Jun Ming Guo ◽  
Bao Sen Wang ◽  
Ying He
Keyword(s):  
Combustion Synthesis ◽  
Synthesis Method ◽  
Solution Combustion Synthesis ◽  
Xrd Analysis ◽  
Cycling Performance ◽  
X Ray Diffraction ◽  
Solution Combustion ◽  
Electrochemical Test ◽  
Micro Morphology ◽  
Better Than

Single phase Al3+ doped LiMn2O4 has been prepared by flameless solution combustion synthesis method at 600oC for 1h. X-ray diffraction (XRD) and scanning electric microscope (SEM) were used to determine the phase composition and micro morphology of the products. XRD analysis indicates that the purities increase and the lattice parameters of the products decrease with increasing Al3+ content. Electrochemical test indicates that the cycling performance of the products with Al3+ doping are better than that of the product without Al3+ doping. The product LiAl0.10Mn1.90O4 gets the best electrochemical performance. At the current density of 30mA/g, the initial discharge capacity of LiAl0.10Mn1.90O4 is 124.8mAh/g, and after 20 cycles, the capacity retention is more than 89%. SEM investigation indicates that the particles of LiAl0.10Mn1.90O4 are sub-micron in size and well dispersed.

Temperature Dependence of LiMn2O4 Prepared by a Solution Combustion Synthesis in the System of Acetate Salts and Acetic Acid

2012 ◽  
Vol 485 ◽  
pp. 465-468
Author(s):  
Li Li Zhang ◽  
Gui Yang Liu ◽  
Jun Ming Guo ◽  
Bao Sen Wang ◽  
Ying He
Keyword(s):  
Acetic Acid ◽  
Combustion Synthesis ◽  
Raw Materials ◽  
Synthesis Method ◽  
Solution Combustion Synthesis ◽  
Electrochemical Performances ◽  
Metal Foil ◽  
X Ray Diffraction ◽  
Solution Combustion ◽  
Acid Ratio

Spinel LiMn2O4 have been prepared by the solution combustion synthesis method using acetate salts as raw materials and acetic acid as fuel. The phase compositions of the as-prepared products were determined by X-ray diffraction (XRD). The electrochemical performance of the products was tested by using a coin-type half battery versus lithium metal foil as anode material. XRD results suggested that the purities of the products prepared at 500oC are higher than these of the products prepared at 600oC. For the products prepared at 500oC, the purities of the products increase with increasing acetic acid ratios. But for the products prepared at 600oC, the purities of the products decrease with increasing acetic acid ratios. The performance tests indicated that the electrochemical performances of the products prepared at 500oC are better than these of the products prepared at 600oC. The product prepared at 500oC with the acetic acid ratio of 1.0 gets the best performance. The initial capacity of it reaches to 124.8mAh/g at the current density of 75mA/g, and after 50 cycles, the capacity retention is 93.7%.

LiAl0.1Mn1.9O4 Prepared by a Solution Combustion Synthesis Using Acetate as Raw Materials and Acetic Acid as Fuel: Effect of Further Calcination Time

2012 ◽  
Vol 485 ◽  
pp. 473-477
Author(s):  
Gui Yang Liu ◽  
Jun Ming Guo ◽  
Li Li Zhang ◽  
Jing Wang ◽  
Bao Sen Wang ◽  
...  
Keyword(s):  
Combustion Synthesis ◽  
Raw Materials ◽  
Synthesis Method ◽  
Solution Combustion Synthesis ◽  
Metal Foil ◽  
X Ray Diffraction ◽  
Calcination Time ◽  
Solution Combustion ◽  
X Ray ◽  
Discharge Capacities

LiAl0.1Mn1.9O4 materials were prepared by a solution combustion synthesis method. In order to improve the purity of the products, the effect of further calcination time was investigated. The phase compositions of the as-prepared products were determined by X-ray diffraction (XRD). The electrochemical performance of the products was tested by using a coin-type half battery versus lithium metal foil as anode material. XRD results suggested that the main phase of the products was LiAl0.1Mn1.9O4, and there was a trace amount Mn2O3 impurity in some of the products. The purity, crystallinity and grain size of the LiAl0.1Mn1.9O4 were increased with increasing further calcination time. Electrochemical experiments demonstrate that the initial discharge capacities of the products with further calcination time of 0, 6, 12 and 24h were 93.7, 105.7, 114.0 and 120.6mAh/g, and about 89.8, 89.5, 89.2 and 88.3% of the initial capacities were retained after 25 cycles, respectively. Further calcination time can enhance the initial capacity, but is not favorable for the cycle ability of the products.

Ni Doped LiMn2O4 Prepared by a Flameless Combustion Synthesis

2012 ◽  
Vol 625 ◽  
pp. 251-254 ◽  
Author(s):  
Gui Yang Liu ◽  
Bao Sen Wang ◽  
Ying He ◽  
Jun Ming Guo
Keyword(s):  
Combustion Synthesis ◽  
Raw Materials ◽  
Synthesis Method ◽  
Solution Combustion Synthesis ◽  
Electrochemical Performances ◽  
X Ray Diffraction ◽  
Galvanostatic Charge ◽  
Solution Combustion ◽  
Limn2o4 Spinel ◽  
X Ray

In this paper, LiNixMn2−xO4 materials were prepared by solution combustion synthesis method using acetic salts as raw materials and acetic acid as fuel. The phase structures are characterized by X-ray diffraction (XRD). Electrochemical performances of the materials are investigated by galvanostatic charge/discharge methods. XRD results revealed that the main phase of the products with increasing Ni3+ content is LiMn2O4, and there is a trace amount of Mn3O4 found in the product with Ni3+ content of 0.05. Electrochemical experiments showed that the capacity and the cyclability of the LiNixMn2−xO4 materials decrease with increasing Ni3+ content. Ni3+ doping has no significantly improvement for the capacity and the cyclability of the LiMn2O4 spinel.

LiMn2O4 Prepared by a Flameless Solution Combustion Synthesis: The Effect of Ignition Temperature

2011 ◽  
Vol 142 ◽  
pp. 213-216
Author(s):  
Gui Yang Liu ◽  
Jun Ming Guo ◽  
Yan Nan Li ◽  
Bao Sen Wang ◽  
Ying He
Keyword(s):  
Electrochemical Performance ◽  
Combustion Synthesis ◽  
Phase Structure ◽  
Ignition Temperature ◽  
Present Method ◽  
Single Phase ◽  
Raw Materials ◽  
Solution Combustion Synthesis ◽  
Solution Combustion ◽  
Micro Morphology

Spinel LiMn2O4 have been prepared by a flameless solution combustion synthesis, using nitrate and acetate salts as raw materials without any fuels. The effect of ignition temperature on the phase structure, micro morphology and electrochemical performance has been studied. The results indicate that spinel LiMn2O4 with single phase can be prepared successfully by the present method at the ignition temperatures of 300-800°C and calcination temperature of 600°C for 5h. The crystallinity, dispersity of the gains and electrochemical performance of the products increase with the decreasing ignition temperatures.

Preparation of LiMn2O4 by a Solution Combustion Synthesis Using Acetic Salts and Acetic Acid as Starting Materials

2011 ◽  
Vol 412 ◽  
pp. 107-110
Author(s):  
Bao Sen Wang ◽  
Jun Ming Guo ◽  
De Wei Guo ◽  
Gui Yang Liu ◽  
Li Li Zhang
Keyword(s):  
Acetic Acid ◽  
Electrochemical Performance ◽  
Combustion Synthesis ◽  
Current Density ◽  
Specific Capacity ◽  
Solution Combustion Synthesis ◽  
Molar Ratio ◽  
Manganese Acetate ◽  
Metal Foil ◽  
Solution Combustion

Spinel LiMn2O4was synthesized by a solution combustion synthesis using lithium and manganese acetate as raw materials and acetic acid as fuel. The phase composition and micro morphology of the as-prepared products were determined by X-ray diffraction (XRD) and scanning electric microscope (SEM). The electrochemical performance of the products was tested by using a coin-type half battery versus lithium metal foil as anode material. XRD analysis suggested that the main phase of the products was LiMn2O4, but there was little impurity Mn2O3in the products. The relative content of Mn2O3was decreased gradually when the molar ratio of Li:Mn: acetic acid increased from 0.5:1:0.5 to 0.5:1:2, but increased again when the molar ratio of Li:Mn: acetic acid was 0.5:1:2.5. The purest product could be prepared when the molar ratio of Li:Mn: acetic acid=0.5:1:2. SEM investigation indicated that the typical crystal structure could not be investigated from the as-prepared products, and the particles were badly agglomerated. Electrochemical performance tests indicated that the specific capacity of the purest product was 108mAh/g. After 30 cycles, the capacity faded only 22% at the current density of 50mA/g, and the average charge/discharge efficiency was ~96%. At the current density of 75mA/g, the initial specific capacity of the purest product was only 72mAh/g, but after 30 cycles, the capacity retention was >92%, exhibiting a good cycling performance.

A Contrastive Study on LiMn2O4 Prepared by Solution Combustion Synthesis Using Nitrate or Acetate Salts as Raw Materials

2011 ◽  
Vol 142 ◽  
pp. 205-208 ◽  
Author(s):  
Gui Yang Liu ◽  
Jun Ming Guo ◽  
Li Li Zhang ◽  
Bao Sen Wang ◽  
Ying He
Keyword(s):  
Acetic Acid ◽  
Combustion Synthesis ◽  
Raw Materials ◽  
Solution Combustion Synthesis ◽  
Electrochemical Performances ◽  
X Ray Diffraction ◽  
Solution Combustion ◽  
X Ray ◽  
Contrastive Study ◽  
Nitrate Salts

In this paper, spinel LiMn2O4 was prepared by the solution combustion synthesis using acetate or nitrate salts as raw materials and acetic acid as fuel. The composition and phase structure are determined by X-ray diffraction (XRD) and the electrochemical performance is tested by using a coin type half-battery versus Li+/Li. The results indicate that the products prepared from acetate salts have higher purities, higher crystallinities and better electrochemical performances than these of the products prepared from nitrate salts. And for the products prepared from acetate salts, the performance becomes worse with increasing acetic acid ratios. Contrarily, for the products prepared from nitrate salts, the performance becomes little better with increasing acetic acid ratios.

Effect of Single or Double Calcination on LiMn2O4 Prepared by a Solution Combustion Synthesis

2011 ◽  
Vol 216 ◽  
pp. 134-137 ◽  
Author(s):  
Gui Yang Liu ◽  
Jun Ming Guo ◽  
Yan Nan Li ◽  
Bao Sen Wang
Keyword(s):  
Combustion Synthesis ◽  
Single Phase ◽  
Raw Materials ◽  
Rate Capability ◽  
Solution Combustion Synthesis ◽  
X Ray Diffraction ◽  
Solution Combustion ◽  
Micro Morphology ◽  
Acetate Mixture ◽  
Better Than

Single phase LiMn2O4 spinel powders have been prepared by solution combustion synthesis at 400 and 500°C using nitrate-acetate mixture raw materials without any fuels. The effect of single or double calcination has been studied contrastively. The phase composition and micro morphology are investigated by X-ray diffraction (XRD) and scanning electric microscope (SEM). The XRD results indicate that single phase LiMn2O4 can be obtained by single calcination at 400°C and 500°C, but there is Mn2O3 impurity in the sample prepared by double calcination at 500°C. SEM investigation exhibits that the particle size increases with raising calcination temperature or double calcination. The electrochemical performance tests indicates that the initial capacity, cyclic performance and rate capability of the samples prepared by single calcination are better than these of the samples prepared by double calcination.

Al Doped LiMn2O4 Prepared by a Solution Combustion Synthesis Using Acetate Salts as Raw Materials and Acetic Acid as Fuel

2011 ◽  
Vol 142 ◽  
pp. 209-212
Author(s):  
Gui Yang Liu ◽  
Jun Ming Guo ◽  
Li Li Zhang ◽  
Bao Sen Wang ◽  
Ying He
Keyword(s):  
Acetic Acid ◽  
Combustion Synthesis ◽  
Raw Materials ◽  
Synthesis Method ◽  
Solution Combustion Synthesis ◽  
Electrochemical Performances ◽  
X Ray Diffraction ◽  
Solution Combustion ◽  
X Ray ◽  
Charge Discharge

To improve the cyclability of spinel LiMn2O4, Al3+doped LiAlxMn2−xO4(x=0, 0.01, 0.05 and 0.10) materials are prepared using a solution combustion synthesis method using acetic salts as raw materials and acetic acid as fuel. Their phase structures are characterized by X-ray diffraction (XRD). Electrochemical performances of the materials are investigated by galvanostatic charge/discharge methods. XRD results reveal that the purity of the samples increases with increasing Al3+content. Electrochemical experiments demonstrate that the charge/discharge cyclability of the LiAlxMn2-xO4increases with increasing Al3+content. Compared with the pristine LiMn2O4, the Al-doped LiAlxMn1−xO4show the obviously improved cyclability, especially for the sample LiAl0.1Mn1.9O4.

Effect of Nitric Acid Modification on LiMn2O4 Prepared by Solution Combustion Synthesis

2011 ◽  
Vol 80-81 ◽  
pp. 332-336 ◽  
Author(s):  
Yan Xia ◽  
Mei Huang ◽  
Jun Ming Guo ◽  
Ying Jie Zhang
Keyword(s):  
Nitric Acid ◽  
Combustion Synthesis ◽  
Discharge Capacity ◽  
Retention Rate ◽  
Solution Combustion Synthesis ◽  
Manganese Acetate ◽  
Solution Combustion ◽  
Acid Modification ◽  
Capacity Retention ◽  
Liquid Combustion

Effect of nitric acid and the burning time on the liquid combustion synthesis of spinel LiMn2O4 has been studied, using lithium nitrite and Manganese acetate as raw a material. The results show that the main phases are all LiMn2O4, which can be obtained at 400-600 oC. Before modified, the impurity is Mn3O4 or Mn2O3. After modified, the impurity is only Mn3O4. The aggregation obviously reduced after adding nitric acid, it is indicated that the crystalline increased. With the increasing temperatures, the modified particle size was increased and the aggregation reduced. The initial discharge capacity and cycle stability improved at some extent too. Its first discharge capacity was 104.6, 112.8 and 117.7mAh/g synthesized at 400, 500, 600 oC, respectively, and the 30th capacity retention rate were 84.89%, 80.67% and 73.24%.

Sign in / Sign up

Export Citation Format

Share Document