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The binder migration due to the capillary force‐driven solvent evaporation during the drying process in the electrode manufacturing process induces inhomogeneous binder distribution in the electrode, which deteriorates Li‐ion kinetics and corresponding poor fast‐charging properties in lithium‐ion batteries (LIBs). Here, we report an effective strategy to mitigate the binder migration behavior by applying an electric field during the drying process. As the employed carboxymethyl cellulose (CMC) and styrene‐butadiene rubber (SBR) binders have a negative charge in an aqueous anode slurry system (pH 7), the binder migration behavior could be mitigated by generating an electrical attraction force into the bottom direction by positive electrification of the current collector. The anode prepared with electric field exhibits homogeneous binder distribution in the longitudinal direction, which enhances Li‐ion kinetics, corresponding constant current charging capacity, and cycling stability compared to those of the anode prepared without electric field. [ABSTRACT FROM AUTHOR]

The effects of substituting the B cation in A3BO7 ceramics on their thermal physical properties were investigated by applying a large mass difference. Y3(Nb1‐xTax)O7 (x = 0, 0.1, 0.2, 0.3, 0.4, and 0.5) ceramics were synthesized, and their structural characteristics were determined. All the fabricated Y3(Nb1‐xTax)O7 ceramics showed defective fluorite structures and glass‐like low thermal conductivity (1.18−2.04 W/m∙K at 25°C) because of the highly distorted crystal structure and significant mass difference. Substitution with Ta5+ enhanced the sintering resistance, leading to superior thermal‐insulating performance via grain boundary scattering. Furthermore, the ceramics exhibited excellent coefficients of thermal expansion, implying the promising applicability of Y3(Nb1‐xTax)O7 as new thermal barrier materials. The effect of mass difference on the thermomechanical properties of the ceramics was examined, suggesting a simple strategy for engineering the chemical composition of new thermal barrier materials. [ABSTRACT FROM AUTHOR]

Stretchable devices significantly expand the scope of applications such as flexible displays and wearable devices/sensors. To enable stretchable wearable electronics, methods for connecting unit devices and developing circuits are required. Previously, research was performed to manufacture circuits with 3D structures or patterns that remain intact when the flexible and stretchable substrates are deformed. A method for drawing a circuit directly on a substrate with a conductive ink pen is proposed, although it is limited by the surface properties of the substrate. Most existing transparent papers are not sufficiently stretchable for flexible and wearable electronics applications. Therefore, a polydimethylsiloxane–cellulose nanocrystals (PDMS–CNC) composite paper is developed that is both highly flexible and stretchable, while maintaining a high transmittance. The versatility of the composite paper is demonstrated as a suitable substrate for flexible devices by patterning with a conductive ink pen. The PDMS–CNC composite paper has an excellent transmittance of ≈70%, and can withstand over 800% tensile strain. The patterned circuits have only minor increase in resistance after a 50% deformation and recovery. The composite paper is a suitable technology for fabricating electrical components and devices for the Internet of Things and wearable and flexible electronics applications. [ABSTRACT FROM AUTHOR]

The styrene-butadiene rubber (SBR) binder migration caused by the capillary force-driven solvent evaporation during the drying process results in the concentration gradient of SBR binder in the anode, which deteriorates the adhesion strength at the interface between the anode film and Cu current collector and Li-ion kinetics, respectively. Here, we report SBR patterned Cu current collector (SPC) to overcome problems caused by the SBR binder migration behavior. Pre-patterned SBR strongly adheres to the Cu current collector, which suppresses its migration during the drying process. Homogeneous SBR distribution in the longitudinal direction of the anode improves the adhesion strength and Li-ion kinetics. Enhanced adhesion strength enables the reduction of the SBR content in the anode, which further improves Li-ion kinetics. The anode employing SPC exhibits improved constant current charging capacity retention and cycling stability compared to those of the anode with a pristine Cu current collector. • Highly adhesive SBR patterned Cu (SPC) was prepared by facile bar-coating process. • SPC enables homogeneous SBR distribution in the anode. • SPC improves adhesion strength and Li-ion kinetics in the anode. • Enhanced adhesion strength reduces SBR content in the anode, improving kinetics. • The anode employing SPC exhibits improved electrochemical properties. [ABSTRACT FROM AUTHOR]