Phase separation of a binary mixture with an external force field

Bertei, Antonio; Mauri, Roberto

doi:10.1016/j.ces.2022.118128

Cited by 2 publications

(1 citation statement)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…where chemical potentials are used for the neutral species LiAM and AM in phase am. By treating the active material phase as a binary mixture of empty (AM) and occupied (LiAM) sites, the chemical potential difference µ Li = µ LiAM − µ AM can be defined [42][43][44]. Such a chemical potential difference µ Li captures at the mesoscale the chemical energy associated to the lattice rearrangement of the active material upon intercalation.…”

Section: Thermodynamic Backgroundmentioning

confidence: 99%

Intercalation in Li-ion batteries: thermodynamics and its relation to non-ideal solid-state diffusion

Lagnoni,

Armiento,

Nicolella

et al. 2024

Prog. Energy

Self Cite

View full text Add to dashboard Cite

Intercalation is the key phenomenon taking place in lithium-ion batteries: while its thermodynamics sets the equilibrium voltage of active materials, solid-state diffusion of intercalated lithium determines the rate at which the battery can operate. This study revisits the thermodynamics of intercalation by treating the active material as a binary mixture of filled and empty sites, thus relating the equilibrium potential to the chemical potential difference of intercalated lithium. By setting a reference to unitary activity at half state-of-lithiation, the non-ideal behaviour of the active material is quantified via a revisited form of the thermodynamic enhancement factor, revealing that common solid-solution cathode materials as LiNixMnyCo1-x-yO2, LiNi0.8Co0.15Al0.05O2, and LiCoO2 show strong super-ideal behaviour. The latter is related to the thermodynamic enhancement of the diffusion coefficient of intercalated lithium. A comprehensive overview of the functional forms of Li diffusion flux according to linear irreversible thermodynamics is provided and related to the chemical diffusion coefficient obtained by conventional characterisation techniques. A literature analysis made on solid-solution cathode active materials reveals that while the chemical diffusion coefficient varies significantly with state-of-lithiation, there exists a convenient functional form of diffusion flux according to linear irreversible thermodynamics that enables a fairly stable diffusion coefficient with state-of-lithiation. This has clear benefits from both modelling and experimental viewpoints and potentially sheds light on the mechanistic fundamentals of solid-state diffusion.

show abstract

Section: Thermodynamic Backgroundmentioning

confidence: 99%

Intercalation in Li-ion batteries: thermodynamics and its relation to non-ideal solid-state diffusion

Lagnoni,

Armiento,

Nicolella

et al. 2024

Prog. Energy

Self Cite

View full text Add to dashboard Cite

show abstract

Phase segregation of a partially miscible binary mixture subjected to an external force field

Chueh,

Mauri,

Bertei

2024

J. Fluid Mech.

View full text Add to dashboard Cite

When a partially miscible binary mixture is quenched below its critical temperature, it transitions from its single-phase to a two-phase region, undergoing phase separation. The processes of formation and coalescence of droplets are driven by diffusive and convective phenomena, taking place isotropically in the system. The application of an external force field, which exerts a different contribution on the two species, breaks the symmetry of phase separation, leading to the segregation of two equilibrated phases separated by a single interface. This study investigates the dynamics of phase segregation under an external force. The effects of various force magnitudes, captured by the Bond number, in both high- and low-viscosity mixtures, distinguished by different fluidity numbers, are quantified via numerical simulations by using the phase field model. The intricate dynamics of formation, floating and coalescence of droplets towards complete segregation are described along with the quantification of the segregation time, revealing different patterns for high and low Bond numbers. Results show that in none of the cases, formation and floating can be regarded as strictly serial processes. A universal scaling between segregation time, Bond number, fluidity number and domain size is not possible, with a power-law dependence emerging only under the diffusion-dominated regime.

show abstract

Phase separation of a binary mixture with an external force field

Cited by 2 publications

References 47 publications

Intercalation in Li-ion batteries: thermodynamics and its relation to non-ideal solid-state diffusion

Intercalation in Li-ion batteries: thermodynamics and its relation to non-ideal solid-state diffusion

Phase segregation of a partially miscible binary mixture subjected to an external force field

Contact Info

Product

Resources

About