Comparative Studies on Monolayer and Bilayer Phosphorous as the Anodes of Li Ion Battery

Recently, two-dimensional (2D) materials have been rapidly developed and they provided a wide application on the anode of the batteries, reducing the adverse effect of traditional ion batteries including low capacity, short cycle life, low charging rate and poor safety mainly coming from the use of graphite anode. The current report investigates the anode performances of AlSi, a new 2D material exfoliated from NaAlSi, for Li ion batterys (LIBs) through density functional theory (DFT) calculations and gives quantitative discussions on the Li ion valences, binding energies and open-circuit voltages of 2D AlSi anode. The results indicate that 2D AlSi performs great as a novel anode due to the moderate adhesion to Li and low barrier for ion diffusion. Furthermore, our research results illustrate a broad application prospect on the new anode inventions as well as reducing useless consumption on the batteries by the practice of AlSi anode.

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A density functional theory study of the carbon-coating effects on lithium iron borate battery electrodes

Physical Chemistry Chemical Physics ◽

10.1039/c6cp06312h ◽

2017 ◽

Vol 19 (3) ◽

pp. 2087-2094 ◽

Cited By ~ 10

Author(s):

Simon Loftager ◽

Juan María García-Lastra ◽

Tejs Vegge

Keyword(s):

Density Functional Theory ◽

Cathode Material ◽

Carbon Coating ◽

Density Functional ◽

Li Ion Battery ◽

Density Functional Theory Study ◽

Iron Borate ◽

Functional Theory ◽

Carbon Coatings ◽

Li Ion

Density functional theory modelling shows that carbon coatings on a LiFeBO3 cathode material does not impede the Li transport in a Li-ion battery.

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Defects, Diffusion, and Dopants in Li2Ti6O13: Atomistic Simulation Study

Materials ◽

10.3390/ma12182851 ◽

2019 ◽

Vol 12 (18) ◽

pp. 2851 ◽

Cited By ~ 5

Author(s):

Navaratnarajah Kuganathan ◽

Sashikesh Ganeshalingam ◽

Alexander Chroneos

Keyword(s):

Electronic Structures ◽

Atomistic Simulation ◽

Density Functional ◽

High Capacity ◽

Ion Diffusion ◽

Functional Theory ◽

Energy Process ◽

Defect Energy ◽

Li Ion ◽

Isovalent Dopant

In this study, force field-based simulations are employed to examine the defects in Li-ion diffusion pathways together with activation energies and a solution of dopants in Li2Ti6O13. The lowest defect energy process is found to be the Li Frenkel (0.66 eV/defect), inferring that this defect process is most likely to occur. This study further identifies that cation exchange (Li–Ti) disorder is the second lowest defect energy process. Long-range diffusion of Li-ion is observed in the bc-plane with activation energy of 0.25 eV, inferring that Li ions move fast in this material. The most promising trivalent dopant at the Ti site is Co3+, which would create more Li interstitials in the lattice required for high capacity. The favorable isovalent dopant is the Ge4+ at the Ti site, which may alter the mechanical property of this material. The electronic structures of the favorable dopants are analyzed using density functional theory (DFT) calculations.

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Decomposition of LiPF6 and Stability of PF5 in Li-Ion Battery Electrolytes. Density Functional Theory and Molecular Dynamics Studies.

ChemInform ◽

10.1002/chin.200407001 ◽

2004 ◽

Vol 35 (7) ◽

Cited By ~ 1

Author(s):

Ken Tasaki ◽

Katsuya Kanda ◽

Shinichiro Nakamura ◽

Makoto Ue

Keyword(s):

Molecular Dynamics ◽

Density Functional Theory ◽

Density Functional ◽

Li Ion Battery ◽

Functional Theory ◽

Li Ion

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Evidence for a Solid-Electrolyte Inductive Effect in Superionic Conductors

10.26434/chemrxiv.13075745 ◽

2020 ◽

Author(s):

Sean Culver ◽

Alex Squires ◽

Nicolo Minafra ◽

Callum Armstrong ◽

Thorben Krauskopf ◽

...

Keyword(s):

Solid Electrolyte ◽

Solid Electrolytes ◽

Density Functional ◽

Inductive Effect ◽

Ionic Conductivities ◽

Lithium Ion ◽

Density Functional Theory Calculations ◽

Ion Diffusion ◽

Functional Theory ◽

Li Ion

Identifying and optimizing highly-conducting lithium-ion solid electrolytes is a critical step towards the realization of commercial all–solid-state lithium-ion batteries. Strategies to enhance ionic conductivities in solid electrolytes typically focus on the effects of modifying their crystal structures or of tuning mobile-ion stoichiometries. A less-explored approach is to modulate the chemical-bonding interactions within a material to promote fast lithium-ion diffusion. Recently, the idea of a solid-electrolyte inductive effect was proposed, whereby changes in bonding within the solid-electrolyte host-framework modify the potential-energy landscape for the mobile ions, resulting in an enhanced ionic conductivity. This concept has since been invoked to explain anomalous conductivity trends in a number of solid electrolytes. Direct evidence for a solid-electrolyte inductive effect, however, is lacking—in part because of the challenge of quantifying changes in local bonding interactions within a solid-electrolyte host-framework. <a></a><a>Here, we consider the evidence for a solid-electrolyte inductive effect in the archetypal superionic lithium-ion conductor Li10Ge1−xSnxP2S12, using Rietveld refinements against high-resolution temperature-dependent neutron-diffraction data, Raman spectroscopy, and density functional theory calculations.</a> Substituting Ge for Sn weakens the {Ge,Sn}–S bonding interactions and increases the charge-density associated with the S2- ions. This charge redistribution modifies the Li+ substructure causing Li+ ions to bind more strongly to the host-framework S anions; which in turn modulates the Li-ion potential-energy surface, increasing local barriers for Li-ion diffusion. Each of these effects is consistent with the predictions of the solid-electrolyte inductive effect model. Density functional theory calculations further predict that this inductive effect occurs even in the absence of changes to the host-framework geometry due to Ge → Sn substitution. These results provide direct evidence in support of a measurable solid-electrolyte inductive effect and demonstrate its application as a practical strategy for tuning ionic conductivities in superionic lithium-ion conductors.

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From Used Oxide Nuclear Fuel to Rechargeable Battery: A First-Principles Study

MRS Proceedings ◽

10.1557/opl.2013.732 ◽

2013 ◽

Vol 1541 ◽

Author(s):

Binbin Wu ◽

Jianguo Yu

Keyword(s):

First Principles ◽

Density Functional ◽

Nuclear Reactions ◽

Open Circuit ◽

Functional Theory ◽

Oxide Nuclear Fuel ◽

Alternative Solutions ◽

Work First ◽

Open Circuit Voltages ◽

Grid Storage

AbstractAlthough uranium oxides have played essential roles in many nuclear reactions, it is imperative to pursue alternative solutions to reuse the spent fuels due to paramount safety and economic concern. Spent nuclear oxide fuels include uranium dioxide (UO2), triuranium octoxide (U3O8) and uranium trioxide (UO3). In this work, first principles calculations based on density functional theory (DFT) were carried out on MUO2, MU3O8 and MUO3 (M= Li, Na and K) to explore their possibilities to serve as grid-storage-based cathode materials. In particular, the result of the optimal structures, average open circuit voltages (OCV) and mechanic stabilities during charge and discharge processes are presented. These results are also compared to available experimental data.

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Evidence for a Solid-Electrolyte Inductive Effect in Superionic Conductors

10.26434/chemrxiv.13075745.v1 ◽

2020 ◽

Author(s):

Sean Culver ◽

Alex Squires ◽

Nicolo Minafra ◽

Callum Armstrong ◽

Thorben Krauskopf ◽

...

Keyword(s):

Solid Electrolyte ◽

Solid Electrolytes ◽

Density Functional ◽

Inductive Effect ◽

Ionic Conductivities ◽

Lithium Ion ◽

Density Functional Theory Calculations ◽

Ion Diffusion ◽

Functional Theory ◽

Li Ion

Identifying and optimizing highly-conducting lithium-ion solid electrolytes is a critical step towards the realization of commercial all–solid-state lithium-ion batteries. Strategies to enhance ionic conductivities in solid electrolytes typically focus on the effects of modifying their crystal structures or of tuning mobile-ion stoichiometries. A less-explored approach is to modulate the chemical-bonding interactions within a material to promote fast lithium-ion diffusion. Recently, the idea of a solid-electrolyte inductive effect was proposed, whereby changes in bonding within the solid-electrolyte host-framework modify the potential-energy landscape for the mobile ions, resulting in an enhanced ionic conductivity. This concept has since been invoked to explain anomalous conductivity trends in a number of solid electrolytes. Direct evidence for a solid-electrolyte inductive effect, however, is lacking—in part because of the challenge of quantifying changes in local bonding interactions within a solid-electrolyte host-framework. <a></a><a>Here, we consider the evidence for a solid-electrolyte inductive effect in the archetypal superionic lithium-ion conductor Li10Ge1−xSnxP2S12, using Rietveld refinements against high-resolution temperature-dependent neutron-diffraction data, Raman spectroscopy, and density functional theory calculations.</a> Substituting Ge for Sn weakens the {Ge,Sn}–S bonding interactions and increases the charge-density associated with the S2- ions. This charge redistribution modifies the Li+ substructure causing Li+ ions to bind more strongly to the host-framework S anions; which in turn modulates the Li-ion potential-energy surface, increasing local barriers for Li-ion diffusion. Each of these effects is consistent with the predictions of the solid-electrolyte inductive effect model. Density functional theory calculations further predict that this inductive effect occurs even in the absence of changes to the host-framework geometry due to Ge → Sn substitution. These results provide direct evidence in support of a measurable solid-electrolyte inductive effect and demonstrate its application as a practical strategy for tuning ionic conductivities in superionic lithium-ion conductors.

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Li Storage on TCNE and TCNE-(Doped)-Graphene Complexes: a Computational Study

MRS Proceedings ◽

10.1557/opl.2014.849 ◽

2014 ◽

Vol 1679 ◽

Cited By ~ 4

Author(s):

Yingqian Chen ◽

Sergei Manzhos

Keyword(s):

Density Functional ◽

Computational Study ◽

Binding Energies ◽

Surface Oxygen ◽

Li Ion Batteries ◽

Functional Theory ◽

Doped Graphene ◽

Li Ion ◽

Li Storage ◽

Surface Oxygen Atom

ABSTRACTLi attachment to free tetracyanoethylene (TCNE) molecules and TCNE adsorbed on doped graphene is studied using density functional theory. While TCNE is adsorbed only weakly on ideal graphene, we identified a configuration in which TCNE is chemisorbed on Al-doped graphene via its C atom and a surface oxygen atom. Up to four Li atoms can be stored on both free and adsorbed TCNE with binding energies stronger than cohesive energy of the Li metal. TCNE immobilized on the conducting graphene-based substrate could therefore become an efficient anode material for organic Li ion batteries.

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