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The research of Li Na's effect of the skill application in the Australia Open during 2013-2014 is analyzed by the means of literature analyzed and date statistic. The research through the statistical analysis of dynamic data on Li...
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The research of Li Na's effect of the skill application in the Australia Open during 2013-2014 is analyzed by the means of literature analyzed and date statistic. The research through the statistical analysis of dynamic data on Li Na two Australian Open tennis technique, tactical index analysis, and learned that Li Nawon the 2014 Australian Open tennis champion, who mainly the key technique, the tactical index is Second Serve Points Won, Average Second Serve Speed, Receiving Points Won, Winners and Double Faults. These five indicators obviously advantage, which is significant differences with rivals.
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The electrochemistries between alkali metals (Li, Na, K, etc.) and chalcogen elements (O, S, Se, Te, etc.) are becoming increasingly important in the field of electrochemical energy storage, because they can be used in advanced el...
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The electrochemistries between alkali metals (Li, Na, K, etc.) and chalcogen elements (O, S, Se, Te, etc.) are becoming increasingly important in the field of electrochemical energy storage, because they can be used in advanced electrochemical energy storage batteries with higher energy densities for powering our future society. Among the best candidates for next-generation high-energy-storage systems, rechargeable metal batteries based on the chalocogen elements such as O and S hold high theoretical energy densities, making them especially attractive.
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摘要 :
The electrochemistries between alkali metals (Li, Na, K, etc.) and chalcogen elements (O, S, Se, Te, etc.) are becoming increasingly important in the field of electrochemical energy storage, because they can be used in advanced el...
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The electrochemistries between alkali metals (Li, Na, K, etc.) and chalcogen elements (O, S, Se, Te, etc.) are becoming increasingly important in the field of electrochemical energy storage, because they can be used in advanced electrochemical energy storage batteries with higher energy densities for powering our future society. Among the best candidates for next-generation high-energy-storage systems, rechargeable metal batteries based on the chalocogen elements such as O and S hold high theoretical energy densities, making them especially attractive.
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Based on model predictions MCFC systems using lithium/potassium carbonate as electrolyte have a limited lifetime under system conditions. By using lithium/sodium carbonate as electrolyte a lifetime exceeding 40,000 hours is obtain...
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Based on model predictions MCFC systems using lithium/potassium carbonate as electrolyte have a limited lifetime under system conditions. By using lithium/sodium carbonate as electrolyte a lifetime exceeding 40,000 hours is obtainable. In addition to the endurance enhancement, application of lithium/sodium carbonate may reduce ohmic and polarization losses because of its higher ionic conductivity. However, for the effect on the polarization resistance, it is necessary to adjust the pore-size distribution of the electrodes to get an optimum performance and to make fully use of the beneficial aspects of this carbonate mixture.
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摘要 :
Based on model predictions MCFC systems using lithium/potassium carbonate as electrolyte have a limited lifetime under system conditions. By using lithium/sodium carbonate as electrolyte a lifetime exceeding 40,000 hours is obtain...
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Based on model predictions MCFC systems using lithium/potassium carbonate as electrolyte have a limited lifetime under system conditions. By using lithium/sodium carbonate as electrolyte a lifetime exceeding 40,000 hours is obtainable. In addition to the endurance enhancement, application of lithium/sodium carbonate may reduce ohmic and polarization losses because of its higher ionic conductivity. However, for the effect on the polarization resistance, it is necessary to adjust the pore-size distribution of the electrodes to get an optimum performance and to make fully use of the beneficial aspects of this carbonate mixture.
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Rechargeable batteries are key components in the energy-conversion-storage-usage chains to implement their stable and efficient utilization. Amongst all of the commercially available secondary batteries, lithium-ion batteries repr...
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Rechargeable batteries are key components in the energy-conversion-storage-usage chains to implement their stable and efficient utilization. Amongst all of the commercially available secondary batteries, lithium-ion batteries represent the state-of-the-art technology. Recently, with the increasing demand for efficient and economic energy storage, advanced post Li-ion batteries, including Li-O_2 and Li-S systems, as well as other metal-ion systems such as Na-ion and Mg-ion systems, have become more and more attractive candidates for the next-generation high-energy batteries. Electrode materials (especially, nanostructured electrode materials) could play an important role in improving the performance of the post Li-ion batteries. Here, we report our recent progress in this field covering Li-S batteries, Li-Se batteries, Na-ion batteries, room-temperature Na-S batteries, as well as Mg-ion batteries.
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摘要 :
Rechargeable batteries are key components in the energy-conversion-storage-usage chains to implement their stable and efficient utilization. Amongst all of the commercially available secondary batteries, lithium-ion batteries repr...
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Rechargeable batteries are key components in the energy-conversion-storage-usage chains to implement their stable and efficient utilization. Amongst all of the commercially available secondary batteries, lithium-ion batteries represent the state-of-the-art technology. Recently, with the increasing demand for efficient and economic energy storage, advanced post Li-ion batteries, including Li-O_2 and Li-S systems, as well as other metal-ion systems such as Na-ion and Mg-ion systems, have become more and more attractive candidates for the next-generation high-energy batteries. Electrode materials (especially, nanostructured electrode materials) could play an important role in improving the performance of the post Li-ion batteries. Here, we report our recent progress in this field covering Li-S batteries, Li-Se batteries, Na-ion batteries, room-temperature Na-S batteries, as well as Mg-ion batteries.
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Oxynitride tantalum perovskites A_xLa_(2/3)Ta_2O_(6-x)N_x with A = Na or Li have been prepared, by reacting La_(2/3)Ta_2O_6 with NaNO_3 or Li(OH), respectively, at 600-950℃ in NH_3 gas atmosphere, and characterised b X-ray powder...
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Oxynitride tantalum perovskites A_xLa_(2/3)Ta_2O_(6-x)N_x with A = Na or Li have been prepared, by reacting La_(2/3)Ta_2O_6 with NaNO_3 or Li(OH), respectively, at 600-950℃ in NH_3 gas atmosphere, and characterised b X-ray powder diffraction, thermogravimetry and impedance measurements. The incorporation of sodium or lithium into La_(2/3)Ta_2O_6 resembles an intercalation and is achieved by a simultaneous replacement of O~(2-) by N~(3-). The compounds formed exhibit the same type of unit cell as La_(2/3)Ta_2O_6 (P4/mmm, a ～ 3.92 , c ～7.91 A). Rietveld refinements of atom site occupancy factors for the sodium containing phases show a preferential occupancy of sodium and lantanum atoms in alternate layers perpendicular to the c axis. Available data suggest that analogous phases with lithium are formed. The latter are lithium ionic conductors with activation energies E_a ≈ 0.8 eV and σ_(max) 1.3X10~(-4) SXcm~(-1) at 300℃. A new oxynitride compound Li_2LaTa_2O_6N has been prepared by reaction of Li_2CO_3, La(OH)_3 and Ta_2O_5 in NH_3 atmosphere at 800-900℃. The crystal structure related to a member in the Ruddlesden-Popper series of perovskite-like phases Sr_(n+1)Ti_nO_(3n+1) with n = 2 and has been refined by the Rietveld method to R_F = 9%, with space group I4/mmm, a = 3.9506(5), c = 18.456(6) A, using Guinier-Haegg Cu/Kα_1 powder diffraction data. The compound is a moderate lithium ion conductor with σ= 3.5 X 10~(-6) S X cm~(-1) at 300℃ and an activation energy E_a = 0.66 eV.
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摘要 :
Oxynitride tantalum perovskites A_xLa_(2/3)Ta_2O_(6-x)N_x with A = Na or Li have been prepared, by reacting La_(2/3)Ta_2O_6 with NaNO_3 or Li(OH), respectively, at 600-950℃ in NH_3 gas atmosphere, and characterised b X-ray powder...
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Oxynitride tantalum perovskites A_xLa_(2/3)Ta_2O_(6-x)N_x with A = Na or Li have been prepared, by reacting La_(2/3)Ta_2O_6 with NaNO_3 or Li(OH), respectively, at 600-950℃ in NH_3 gas atmosphere, and characterised b X-ray powder diffraction, thermogravimetry and impedance measurements. The incorporation of sodium or lithium into La_(2/3)Ta_2O_6 resembles an intercalation and is achieved by a simultaneous replacement of O~(2-) by N~(3-).The compounds formed exhibit the same type of unit cell as La_(2/3)Ta_2O_6 (P4/mmm, a ～ 3.92 , c ～7.91 A). Rietveld refinements of atom site occupancy factors for the sodium containing phases show a preferential occupancy of sodium and lantanum atoms in alternate layers perpendicular to the c axis. Available data suggest that analogous phases with lithium are formed. The latter are lithium ionic conductors with activation energies E_a ≈ 0.8 eV and σ_(max) 1.3X10~(-4) SXcm~(-1) at 300℃. A new oxynitride compound Li_2LaTa_2O_6N has been prepared by reaction of Li_2CO_3, La(OH)_3 and Ta_2O_5 in NH_3 atmosphere at 800-900℃. The crystal structure related to a member in the Ruddlesden-Popper series of perovskite-like phases Sr_(n+1)Ti_nO_(3n+1) with n = 2 and has been refined by the Rietveld method to R_F = 9%, with space group I4/mmm, a = 3.9506(5), c = 18.456(6) A, using Guinier-Haegg Cu/Kα_1 powder diffraction data. The compound is a moderate lithium ion conductor with σ= 3.5 X 10~(-6) S X cm~(-1) at 300℃ and an activation energy E_a = 0.66 eV.
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A potential Lithium-ion battery anode material Li4-xNaxTi5O12 (0≤x≤0.15) has been synthesized via a facile hydrothermal method with short processing time and low temperature. The XRD and FE-SEM results indicate that samples with...
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A potential Lithium-ion battery anode material Li4-xNaxTi5O12 (0≤x≤0.15) has been synthesized via a facile hydrothermal method with short processing time and low temperature. The XRD and FE-SEM results indicate that samples with Na-doped are well-crystallized and have more homogeneous particle distributions with smaller overall particle size in the range of 300-600nm. Electrochemical tests reveal that Na-doped samples exhibit impressive specific capacity and cycle stability compared to pristine Li_4Ti_5O_(12) at high rate. The Li_(3.9)Na_(0.1)Ti_5O_(12) electrode deliver an initial specific discharge capacity of 169mAh/g at 0.5C and maintained at 150.4mAh/g even after 40 cycles with the reversible retention of 88.99%. Finally, a simple solvothermal reduction method was used to fabricate Li3.9Na0.1Ti5O12/graphene (Li3.9Na0.1Ti5O12/G) composite. Galvanostatic charge-discharge tests demonstrate that this sample has remarkable capacities of 197.4mAh/g and 175.5mAh/g at 0.2C and 0.5C rate, respectively. This indicates that the Li3.9Na0.1Ti5O12/G composite is a promising anode material for using in lithium-ion batteries.
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