Structure of Li<sub>2</sub>FeSiO<sub>4</sub>

Nishimura, Shin Ichi; Hayase, Shogo; Kanno, Ryoji; Yashima, Masatomo; Nakayama, Noriaki; Yamada, Atsuo

doi:10.1021/ja805543p

Cited by 259 publications

(213 citation statements)

References 9 publications

(12 reference statements)

Supporting

Mentioning

183

Contrasting

Unclassified

Order By: Relevance

“…Again, this is an indication of the expected decrease in cell volume. There are also in this case some small impurity peaks that could not be identified and that do not match either Mn 3 Figure 3) and PnLiNaMnSiO 4 (Figure 4), the Rietveld refinement of PnLi 2 MnSiO 4 shown in Figure 5 assumed atomic positions fixed at GGA ab initio DFT values (Table 2), while refining only the cell parameters. In this case, however, the Rietveld model giving best agreement with the observed XRD pattern required inclusion of a bimodal distribution of crystallite sizes for PnLi 2 MnSiO 4 .…”

Section: Electrochemical Testing Of Battery Performancementioning

confidence: 99%

Novel Pn Polymorph for Li₂MnSiO₄ and Its Electrochemical Activity As a Cathode Material in Li-Ion Batteries

et al. 2011

View full text Add to dashboard Cite

We report on the synthesis and characterization of a new metastable polymorph of Li 2 MnSiO 4 adopting the Pn space group, prepared by ion-exchange from Na 2 MnSiO 4 . Density-functional theory methods were used to predict the lattice parameters and atom positions of the new polymorph material and those of Na 2 MnSiO 4 and LiNaMnSiO 4 , allowing their identification by X-ray diffraction profiles, as well as the comparison of the measured and calculated cell parameters. The electrochemical activity of this new polymorph as a cathode material for lithium ion batteries was evaluated in coin cells and compared to that of the thermodynamically stable Pmn2 1 polymorph of Li 2 MnSiO 4 , as well as LiNaMnSiO 4 and Na 2 MnSiO 4 . Carbon coating, very vital to the electrochemical activity of the material, was added in situ to the material before ion-exchange because the metastable polymorph converts to the stable polymorph above 370°C, as confirmed by differential scanning calorimetry scans. Both Li 2 MnSiO 4 polymorphs display similar charge−discharge curves, except for a marginally lower lithium extraction voltage during the first charge of the Pn structure that may be due to the presence of sodium ion impurities. A discharge capacity of 110 mA h g −1 is initially observed for both Li 2 MnSiO 4 polymorphs and both exhibit similar capacity fades. LiNaMnSiO 4 , however, yields a stable capacity of 45 mA h g −1 , whereas Na 2 MnSiO 4 yields an initial capacity of 20 mAh g −1 , increasing to 60 mAh g −1 with cycling. KEYWORDS: lithium manganese silicate, polymorphism, Li-ion battery

show abstract

Section: Electrochemical Testing Of Battery Performancementioning

confidence: 99%

Novel Pn Polymorph for Li₂MnSiO₄ and Its Electrochemical Activity As a Cathode Material in Li-Ion Batteries

et al. 2011

View full text Add to dashboard Cite

show abstract

“…Fe, Mn or Co have typically been utilised, with more attention recently devoted to Li2FeSiO4 structures, due in part to reasons of safety and cost. The structure of Li2FeSiO4 has been a focus of a number of recent studies owing to its rich display of polymorphism [494][495][496][497][498][499], where a number of different polymorphs, designated as βI, βII, γ0, γII and γs (see Fig. 35), have been identified and account for an experimental variation in the electrochemical performance of Li2FeSiO4 cathodes [498][499][500].…”

Section: Transition Metal Silicates (Li2msio4)mentioning

confidence: 99%

Evaluating the performance of nanostructured materials as lithium-ion battery electrodes

et al. 2013

View full text Add to dashboard Cite

Access to the full text of the published version may require a subscription. Rights © Tsinghua University Press and Springer-Verlag Berlin ABSTRACTThe performance of the lithium-ion cell is heavily dependent on the ability of the host electrodes to accommodate and release Li + ions from the local structure. While the choice of electrode materials may define parameters such as cell potential and capacity, the process of intercalation may be physically limited by the rate of solid-state Li + diffusion. Increased diffusion rates in lithium-ion electrodes may be achieved through a reduction in the diffusion path, accomplished by a scaling of the respective electrode dimensions.In addition, some electrodes may undergo large volume changes associated with charging and discharging, the strain of which, may be better accommodated through nanostructuring. Failure of the host to accommodate such volume changes may lead to pulverisation of the local structure and a rapid loss of capacity. In this review article, we seek to highlight a number of significant gains in the development of nanostructured lithium-ion battery architectures (both anode and cathode), as drivers of potential next-generation electrochemical energy storage devices.

show abstract

“…In this β-structure, chains of LiO 4 tetrahedra run along the a̲ direction parallel to chains of alternating FeO 4 and SiO 4 tetrahedra. Nishimura et al 5 reported the structure of Li 2 FeSiO 4 prepared at 800°C and designated by these authors as γ s (space group P2 1 ). It differs from the other γ structures in that there are no edge sharing trimers of tetrahedra; instead one set of LiO 4 tetrahedra are arranged in edge sharing pairs with FeO 4 tetrahedra, while the other set of LiO 4 tetrahedra forms edge sharing pairs with itself.…”

Section: ■ Introductionmentioning

confidence: 99%

Insights into Changes in Voltage and Structure of Li₂FeSiO₄ Polymorphs for Lithium-Ion Batteries

et al. 2012

View full text Add to dashboard Cite

ABSTRACT:The search for new low cost, safe, and high capacity cathodes for lithium batteries has focused attention recently on Li 2 FeSiO 4 . The material presents a challenge because it exhibits complex polymorphism, and when it is electrochemically cycled there is a significant drop in the cell voltage related to a structural change. Systematic studies based on density functional theory techniques have been carried out to examine the change in cell voltages and structures for the full range of Li 2 FeSiO 4 polymorphs (β II , γ s , and γ II ) including the newly elucidated cycled structure (termed inverse-β II ). We find that the cycled structure has a 0.18−0.30 V lower voltage than the directly synthesized polymorphs in accord with experimental observations. The trends in cell voltage have been correlated to the change in energy upon delithiation from Li 2 FeSiO 4 to LiFeSiO 4 in which the cation−cation electrostatic repulsion competes with distortion of the tetrahedral framework.

show abstract

Structure of Li₂FeSiO₄

Cited by 259 publications

References 9 publications

Novel Pn Polymorph for Li₂MnSiO₄ and Its Electrochemical Activity As a Cathode Material in Li-Ion Batteries

Novel Pn Polymorph for Li₂MnSiO₄ and Its Electrochemical Activity As a Cathode Material in Li-Ion Batteries

Evaluating the performance of nanostructured materials as lithium-ion battery electrodes

Insights into Changes in Voltage and Structure of Li₂FeSiO₄ Polymorphs for Lithium-Ion Batteries

Contact Info

Product

Resources

About

Structure of Li2FeSiO4

Cited by 259 publications

References 9 publications

Novel Pn Polymorph for Li2MnSiO4 and Its Electrochemical Activity As a Cathode Material in Li-Ion Batteries

Novel Pn Polymorph for Li2MnSiO4 and Its Electrochemical Activity As a Cathode Material in Li-Ion Batteries

Evaluating the performance of nanostructured materials as lithium-ion battery electrodes

Insights into Changes in Voltage and Structure of Li2FeSiO4 Polymorphs for Lithium-Ion Batteries

Contact Info

Product

Resources

About

Structure of Li₂FeSiO₄

Novel Pn Polymorph for Li₂MnSiO₄ and Its Electrochemical Activity As a Cathode Material in Li-Ion Batteries

Novel Pn Polymorph for Li₂MnSiO₄ and Its Electrochemical Activity As a Cathode Material in Li-Ion Batteries

Insights into Changes in Voltage and Structure of Li₂FeSiO₄ Polymorphs for Lithium-Ion Batteries