メインコンテンツへスキップ
A continuum (Doyle–Fuller–Newman) lithium-ion model treats the electrolyte as a binary salt in a single solvent and tracks a single salt concentration cec_e. Closing the equations requires four transport properties as functions of cec_e and temperature TT: The four functions appear together in the modified Nernst–Planck flux for a binary electrolyte and are tightly coupled — a coherent parameter set should report all of them under the same conditions, on the same chemistry, ideally from the same study.

​
How are these properties measured?

Landesfeind & Gasteiger 2019 is one of the few studies that reports all four properties for the same electrolyte systems, using the following techniques.
Measured by AC impedance spectroscopy in a commercial two-platinum-microelectrode conductivity cell with a Peltier-controlled temperature stage. The high-frequency (8585 kHz – 11 kHz) impedance gives the bulk electrolyte resistance, which combined with the cell constant (calibrated against KCl standards) yields κ\kappa.
Measured by galvanostatic-pulse / restricted-diffusion relaxation in Li ∣\mid separator ∣\mid Li symmetric coin cells. A 15-minute current pulse builds up a concentration gradient across the separator; after the current is interrupted, the cell potential decays exponentially over ∼4\sim 4 hours. Fitting the long-time decay U(t)−U∞∝e−t/τU(t) - U_\infty \propto e^{-t/\tau} gives a relaxation time τ\tau, from which De,eff=ℓsep2/(π2τ)D_{e,\mathrm{eff}} = \ell_\mathrm{sep}^2 / (\pi^2 \tau).
These two are extracted together from a combination of two measurements:
  • Concentration cells (pouch cells with two electrolyte compartments at different LiPF6_6 concentrations) give the open-circuit potential UCCU_\mathrm{CC}, which is sensitive to the activity coefficient and to t+0t_+^0.
  • The short-time potential response of the same Li ∣\mid Li pulse experiment used for DeD_e gives a complementary combination of the two quantities.
Together they yield two transport factors aa and bb, which Landesfeind invert via t+0=1−b/at_+^0 = 1 - \sqrt{b/a} and χ=a2/(2b)\chi = a^2 / (2b) — a variant of Newman’s full-cell method.
These are the techniques used in Landesfeind & Gasteiger 2019, but several other experimental approaches exist (Hittorf, NMR-based diffusion, electrophoretic NMR for t+0t_+^0, polarization-relaxation variants, etc.). For a comprehensive review of available methods and a database of digitized literature parameters, see Wang et al. 2022, Review of parameterisation and a novel database (LiionDB) for continuum Li-ion battery models, Prog. Energy 4, 032004.

​
Using these properties in a model

よく使われる文献パラメータ化（定数、Nyman、Landesfeind、Arrhenius ラッパー）には、あらかじめ用意された direct entries が用意されており、整合性のあるパラメータセットをそのままパイプラインに投入できます。物理的背景とパラメータ化の選び方については、Electrolyte direct entries を、これらをプログラムで構成・送信する方法については、Pipelines → Direct Entries を参照してください。