Electronic and Ionic Dynamics Coupled at Solid–Liquid Electrolyte Interfaces in Porous Nanocomposites of Carbon Black, Poly(vinylidene fluoride), and γ-Alumina

Abstract

Better fundamental understanding of the transport properties within nanocomposite materials consisting of interpenetrated percolating networks and used as electrodes is needed to improve their performance for a variety of devices. The simultaneous measurement of their effective ionic and electronic conductivities requires a sophisticated experimental set up. Here, the reciprocal influence of ionic and electronic transfers at different scales of model porous nanocomposites made of carbon black–poly­(vinylidene fluoride)−γ alumina wetted by a nonaqueous electrolyte is investigated by broadband dielectric spectroscopy (BDS) from 40 to 1010 Hz, between 223 and 293 K. Experimental results show that the coupling of electronic and ionic dynamics at interfaces in the nanostructured composite material results in significant decrease of the electronic conductivity compared to the dry state and increase of the ionic conductivity compared to the bulk electrolyte.

Three-Dimensional Printing of a LiFePO4/Graphite Battery Cell via Fused Deposition Modeling

“…Panabière et al . 56 showed that electrons transport mechanism in carbon/polymer mixtures used in battery field was tunneling with no temperature dependence (metal-like behavior). Nonetheless, such temperature dependence would be perceived when strong dipoles are adsorbed at the carbon particles surface.…”

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“…It can be observed that the pure resistance at high frequencies decreases when the temperature increases (Figure b). The first depressed semicircle that was attributed to the contact between the electrode layer and the current collector is not influenced significantly by the temperature, which is typical of electron transport or transfer . The second feature, which was attributed to the distribution of the charge transfer phenomenon through the electrode thickness, is significantly influenced by the temperature.…”

“…The first depressed semicircle that was attributed to the contact between the electrode layer and the current collector is not influenced significantly by the temperature, which is typical of electron transport or transfer. [38] The second feature, which was attributed to the distribution of the charge transfer phenomenon through the electrode thickness, is significantly influenced by the temperature. The amplitude decreases when the temperature increased, as reported in the literature for the charge transfer resistance.…”