Multi‐Foldable and Environmentally Stable All‐Solid‐State Supercapacitor Based on Hierarchical Nano‐Canyon Structured Ionic‐Gel Polymer Electrolyte

Abstract

New ionic-gel polymer electrolytes (IGPEs) are designed for use as electrolytes for all-solid-state supercapacitors (ASSSs) with excellent deformability and stability. The combination of the photochemical reactionbased polymer matrix, weak-binding lithium salt with ionic liquid, and ion dissociating solvator is employed to construct the nano-canyon structured IGPE with high ionic conductivity (σ DC = 1.2 mS cm −1 at 25 °C), high dielectric constant (ε s = 131), and even high mechanical robustness (bending deformation for 10 000 cycles with superior conductivity retention [≈91%]). This gives rise to ASSS with high compatibility and stability, which is compliant with foldable electronics. Consequently, this ASSS delivers remarkable electrochemical performance (specific capacitance of ≈105 F g −1 at 0.22 A g −1 , maximum energy density and power density of 23 and 17.2 kW kg −1 ), long lifetime (≈93% retention after 30 days), wider operating temperature (≈0-120 °C), and mechanical stabilities with no significant capacitance reduction after mechanical bending and multiple folding, confirming the superior electrochemical durability under serious deformation states. Therefore, this ultra-flexible and environmentally stable ASSS based on the IGPE having the nano-canyon morphology can be a novel approach for powering up the ultra-deformable and durable nextgeneration wearable energy storage devices.

Structural pseudocapacitors with reinforced interfaces to increase multifunctional efficiency

“…( E ) CV at a scan rate of 1 mV s −1 on structural supercapacitors with different polymer electrolytes. ( F ) Comparison of energy and power densities in state-of-the-art supercapacitors using solid-state electrolytes: this work using the gradient electrolyte, ionogel ( 48 ), polyethylene glycol diacrylate (PEGDA) ( 49 ), PEO ( 50 ), and SU-8 ( 51 ). ( G ) Capacitance retention and coulombic efficiency of the structural supercapacitor with the gradient electrolyte under full charge-discharge cycles of 3 V at a current density of 2 mA cm −2 .…”

Toughening of poly(ionic liquid)-based ion gels with cellulose nanofibers as a sacrificial network

“…Ion gels, which are composed of three-dimensional cross-linked polymer networks swollen with a large amount of ionic liquid (IL), have recently attracted significant attention as a new class of soft materials because of their unique properties such as high ionic conductivity, [1][2][3][4][5] thermal stability, 6,7 and electrochemical stability, 8,9 processability, 10,11 and handleability. These gels have potential applications in various fields, including as solid-state polyelectrolytes, 12,13 supercapacitors, 14,15 carbon dioxide separation membranes, [16][17][18][19] and as sensors and actuators 2,20,21 in soft electronics. However, their low mechanical strength hinders their practical use.…”

Highly Elastic, Healable, and Durable Anhydrous High‐Temperature Proton Exchange Membranes Cross‐Linked with Highly Dense Hydrogen Bonds

“…Solid electrolytes that can conduct ions have attracted much attention due to their applications in numerous energy storage and conversion systems including fuel cells, lithium-ion batteries, flexible sensors, and supercapacitors. [1][2][3][4][5][6][7][8] With the pursuit of superb energy storage and conversion systems possessing extended service life and enhanced reliability, there is increasing demand for solid electrolytes with excellent durability and working stability. [1,3,4] The solid electrolyte capable of conducting protons and acting as a separator between the fuel and oxidant can be used as the proton exchange membrane (PEM), which plays an important role in PEM fuel cells (PEMFCs).…”