Gel Electrolyte Derived from Poly(ethylene glycol) Blending Poly(acrylonitrile) Applicable to Roll‐to‐Roll Assembly of Electric Double Layer Capacitors

Abstract

The synthesis of a gelled polymer electrolyte (GPE) using poly(ethylene glycol) blending poly(acrylonitrile) (i.e., PAN‐b‐PEG‐b‐PAN) as a host, dimethyl formamide (DMF) as a plasticizer and LiClO4 as an electrolytic salt for electric double layer capacitors (EDLCs) is reported. The PAN‐b‐PEG‐b‐PAN copolymer in the GPE has a linear configuration for high ionic conductivity and excellent compatibility with carbon electrodes. When assembling the GPE in a carbon‐based symmetric EDLC, the copolymer network facilitates ion motion by reducing the equivalent series resistance and Warburg resistance of the capacitor. This symmetric cell has a capacitance value of 101 F g−1 at 0.125 A g−1 and can deliver an energy level of 11.5 Wh kg−1 at a high power of 10 000 W kg−1 over a voltage window of 2.1 V. This cell shows superior stability, with little decay of specific capacitance after 30 000 galvanostatic charge‐discharge cycles. The distinctive merit of the GPE film is its adjustable mechanical integrity, which makes the roll‐to‐roll assembly of GPE‐based EDLCs readily scalable to industrial levels.

High-performance all-solid-state flexible supercapacitors based on manganese dioxide/carbon fibers

“…A single MnO 2 /CFs fiber electrode exhibits a specific volumetric capacitance of 58.7 F cm -3 at 0.1 A g -1 with a specific gravimetric capacitance of 428 F g -1 based on the MnO 2 mass. Two hybrid carbon fiber electrodes were assembled together in parallel with polyvinyl pyrrolidone (PVP)/Na 2 SO 4 gel, which is used as both an electrolyte and a separator [27][28][29][30][31][32][33][34][35][36]. The all-solid-state device displays a high volumetric energy density of 3.8 mWh cm -3 at power density of 89 mW cm -3 with a good flexibility (CV curves almost unchanged after 1000 bending times) and a superior long cycle stability (an 85.8% capacitance retention after 10000 cycles).…”

A Flexible Ionic Liquid Gelled PVA‐Li2SO4 Polymer Electrolyte for Semi‐Solid‐State Supercapacitors

“…This is attributed to the increased amount of charge carriers, Li + ions from Li 2 SO 4 . [ 10,30 ] When the ratio of PVA:BMIMCl:Li 2 SO 4 is 1:3:2.2, the ionic conductivity of the FGPE reaches the maximum value (37 mS cm −1 ).…”

“…It is also a critical factor for attaining highly fl exible devices. [ 10,11 ] Lithium salts, the typical neutral inorganic salts, are mostly widely used in batteries as a high conducting medium. They have attracted much attention in supercapacitors recently because of their high recyclability.…”

“…They have attracted much attention in supercapacitors recently because of their high recyclability. [ 10,14,18 ] Typical GPEs are formed by dissolving salts such as LiCF 3 SO 3 , LiN(SO 2 CF 3 ) 2 , LiPF 6 , LiBF 4 , and LiClO 4 into PVA aqueous solution directly. [ 15 ] The dissociation energy of lithium sulfate (Li 2 SO 4 ) is quite low due to a large ionic radius difference between positive and negative ions.…”

Polyvilylidenefluoride-based Nanocomposite Films Induced-by Exfoliated Boron Nitride Nanosheets with Controlled Orientation

“…Among the recent EES devices, such as fuel cells, batteries, capacitors, and supercapacitors, capacitors possess the advantage of high power density due to their fast electrical energy charge-discharge capability [5,6]. Comparing to recently introduced polymer capacitors (~3 Jcm -3 ) [7,8], the energy densities of commercial capacitors such as batteries and electric capacitors are still high around 10 times [9], while polymer capacitors are potential in view of the extended life span, easier processing, operation under the higher voltages, reduction of the volume, light in weights and lower cost of the electric power systems for advanced electric [10][11][12].…”