Architected Low‐Tortuosity Electrodes with Tunable Porosity from Nonequilibrium Soft‐Matter Processing

Abstract

Mass transport is performance‐defining across energy storage devices, often causing limitations at high current rates. To optimize and balance the device‐scale energy and power density for a given energy storage demand, tailored electrode architectures with precisely controllable phase dimensions are needed in combination with low‐tortuosity channels that maximize the geometric component of diffusion and species flux. A material‐agnostic nonequilibrium soft‐matter process is reported to fabricate free‐standing inorganic composite electrodes with adjustable thicknesses of 100s of µm, featuring straight and accessible channels ranging in diameter from 5–30 µm, coupled with tunable material‐to‐pore ratios. Such architected anode and cathode electrodes exhibit electrochemical and architectural stability over extended cycling in a full‐cell battery. Further, mass‐transport constraints appear at high current densities, and the lithiation step is identified as rate‐performance limiting, a result of insufficient lithium‐ion supply and concentration polarization. The results demonstrate the need for and feasibility of tailored electrode architectures where dimensional ratios between low‐tortuosity channels, the charge‐storing matrix, and electrode thickness are tunable to meet coupled power and energy‐storage requirements.

Retrievable Hierarchically Porous Ferroelectric Ceramics for “Greening” the Piezo‐Catalysis Process

“…Due to the complexity of transport caused by a pore network, effective diffusion coefficient D e was commonly introduced to understand diffusion in porous media. There are two main factors, porosity P and tortuosity 𝜏, affecting D e according to Equation (7) [42] :…”

“…Due to the complexity of transport caused by a pore network, effective diffusion coefficient D e was commonly introduced to understand diffusion in porous media. There are two main factors, porosity P and tortuosity τ , affecting D e according to Equation (7) [ 42 ] : $$$$\begin{equation}{D}_e = \frac{{{D}_0P}}{\tau }\ \end{equation}$$$$where D 0 is a constant representing the diffusion coefficient in bulk solution around ceramics catalysts. According to previous studies of tortuosity‐porosity relations with the utilization of heterogeneous catalyst, [ 43 ] the relationship between P and τ was proposed by: $$$$\begin{equation}{\tau }^2 = P/\left( {1 - {{\left( {1 - P} \right)}}^{1/3}} \right) \end{equation}$$$$…”

Conformal electrodeposition of ultrathin polymeric films with tunable properties from dual-functional monomers

“…5a) using hybrid inorganic phase inversion method. 39 To ensure consistent monomer concentration in the micron-sized pores and accommodate slower diffusion in the 3D-structured electrode, repeating potentiostatic deposition is employed with 5 s applied deposition potential and 10 s rest intervals for diffusional TEG-DP replenishment in the pores (50 mM TEG-DP, E dep = +0.1 V vs. Ag/Ag + ). During the deposition, the anodic current decreases significantly with increasing deposition pulse number, and eventually exhibits almost exclusively double-layer current (Fig.…”

Reasonable design of thick electrodes in lithium-ion batteries

“…When the electrode slurry is cast and immersed in a non-solvent, only the solvent evaporates from the surface. As soon as the slurry was placed in the non-solvent, the solvent was extracted from the electrode surface (Figure 4C) (Resing et al, 2023). During this process, the slurry ratio increases at the top of the electrode, resulting in the formation of a relatively dense skin layer.…”