Journal ArticleDOI
Comparative Kinetic Study of Olivine Li x MPO 4 ( M = Fe , Mn)
TLDR
In this paper, a huge kinetic difference in olivine Li x MPO 4 (M = Fe,Mn) is demonstrated in a quantitative manner, and the current relaxation to the stepwise anodic overvoltage (chronoamperometry) is measured for the Li x FePO 4 and Li x MnPO 4 under identical extrinsic conditions, which are carefully controlled and confirmed using Rietveld refinement for the X-ray diffraction profiles, direct texture observation by scanning electron microscope, Brunauer-Emmett-Teller surface area measurements,Abstract:
A huge kinetic difference in olivine Li x MPO 4 (M = Fe,Mn) is demonstrated in a quantitative manner. Galvanostatic discharge profiles and the current relaxation to the stepwise anodic overvoltage (chronoamperometry) are comparatively measured for the Li x FePO 4 and Li x MnPO 4 under identical extrinsic conditions, which are carefully controlled and confirmed using Rietveld refinement for the X-ray diffraction profiles, direct texture observation by scanning electron microscope, Brunauer-Emmett-Teller surface area measurements, and tap density measurements. The current durability for Li x MnPO 4 is orders-of-magnitude inferior to that of Li x FePO 4 , the origin of which is clearly attributed to their intrinsic crystallographic and transport property differences. Heavy polaronic holes localized on the Mn 3+ sites are suggested as an important rate-limiting factor. In spite of the higher open-circuit voltage of Mn 3+ /Mn 2+ (4.05 V) compared to that of Fe 3+ /Fe 2+ (3.45 V) in the olivine framework, the abnormally large polarization may eliminate pure LiMnP0 4 as a practical lithium battery cathode due to much lower effective energy density than LiFePO 4 .read more
Citations
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Positive Electrode Materials for Li-Ion and Li-Batteries†
TL;DR: In this article, positive electrodes for Li-ion and lithium batteries have been under intense scrutiny since the advent of the Li ion cell in 1991, and a growing interest in developing Li−sulfur and Li−air batteries that have the potential for vastly increased capacity and energy density, which is needed to power large scale systems.
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Polyanionic (phosphates, silicates, sulfates) frameworks as electrode materials for rechargeable Li (or Na) batteries.
TL;DR: For more than 20 years, most of the technological achievements for the realization of positive electrodes for practical rechargeable Li battery systems have been devoted to transition metal oxides such as LixMO2 (M = Co, Ni, Mn), LixMn2O4, LixV2O5, or LIXV3O8.
Journal ArticleDOI
Ultimate Limits to Intercalation Reactions for Lithium Batteries
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High-voltage positive electrode materials for lithium-ion batteries
TL;DR: This review gives an account of the various emerging high-voltage positive electrode materials that have the potential to satisfy the requirements of lithium-ion batteries either in the short or long term, including nickel-rich layered oxides, lithium- rich layeredOxides, high- voltage spinel oxide compounds, and high- voltage polyanionic compounds.
Journal ArticleDOI
The design of a LiFePO4/carbon nanocomposite with a core-shell structure and its synthesis by an in situ polymerization restriction method.
TL;DR: An in situ polymerization restriction method is reported for the synthesis of a nano-sized LiFePO4/carbon composite with a core–shell structure from Fe salts, considered to be one of the most promising cathode materials for the next generation of lithium batteries.
References
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Journal ArticleDOI
Nano-sized transition-metal oxides as negative-electrode materials for lithium-ion batteries
TL;DR: It is reported that electrodes made of nanoparticles of transition-metal oxides (MO), where M is Co, Ni, Cu or Fe, demonstrate electrochemical capacities of 700 mA h g-1, with 100% capacity retention for up to 100 cycles and high recharging rates.
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Phospho‐olivines as Positive‐Electrode Materials for Rechargeable Lithium Batteries
TL;DR: In this article, the authors showed that a reversible loss in capacity with increasing current density appears to be associated with a diffusion-limited transfer of lithium across the two-phase interface.
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Electronically conductive phospho-olivines as lithium storage electrodes
TL;DR: It is shown that controlled cation non-stoichiometry combined with solid-solution doping by metals supervalent to Li+ increases the electronic conductivity of LiFePO4 by a factor of ∼108, which may allow development of lithium batteries with the highest power density yet.
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Optimized LiFePO4 for Lithium Battery Cathodes
TL;DR: LiFePO 4 powders were synthesized under various conditions and the performance of the cathodes was evaluated using coin cells, the samples were characterized by X-ray diffraction, scanning electron microscope observations, Brunauer, Emmett, and Teller surface area measurements, particle-size distribution measurements, and Mossbauer spectroscopy.
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Ti-doped alkali metal aluminium hydrides as potential novel reversible hydrogen storage materials
TL;DR: In this paper, a reversible hydrogen storage system based on catalyzed reactions is proposed, where the catalytic acceleration of the reactions in both directions is achieved by doping alkali metal aluminium hydrides with a few mol% of selected Ti compounds.