Ionic Liquid Modified Electrochemical Capacitor with Long‐Term Performance

Abstract

Ionic liquids are used, for example, as corrosion inhibitors for metals, steel, and metal alloys. The method of preventing corrosion through the whole group of these kinds of compounds, called inhibitors, is to use them as additives to aggressive environments, including aqueous electrolytes. In this article, we present the inhibitive effect of imidazolium ionic liquids with 2,5‐dihydroxybenzenesulfonate anion on the corrosion of 316L stainless steel in neutral medium. In addition, we demonstrate that when the ionic liquid is used as an additive to the electrolyte solution (1 M Na2SO4) of a symmetric carbon/carbon electrochemical capacitor with 316L stainless‐steel current collectors, the capacitor lifetime is significantly extended. The ionic‐liquid additive inhibits corrosion of the current collector surface and, in effect, prevents activated carbon porous space from being blocked by corrosion products.

Interfacial Insights into the Polarization Protocol: Toward Reducing Corrosion and Improving the Cycle Life of Electrochemical Capacitors

“…Cylinders made of 316 L stainless steel served as current collectors. The nominal composition of stainless steel is presented elsewhere. − , Furthermore, the following surface treatment of current collectors was carried out: degreasing in acetone (15 min) and in hot (85 °C) 10% KOH solution (15 min); rinsing with distilled water (15 min); drying in an oven at 80 °C (30 min); and aging (conditioning) in air at 25 °C (24 h).…”

“…Electrochemical capacitors (ECs) are devices capable of storing charge directly in an electric double layer at electrode/electrolyte interfaces or indirectly when charge transfer process across electrode/electrolyte interface is involved. − Unlike batteries, ECs can be fully charged and discharged in a few seconds. Therefore, they are characterized by high power but low energy densities. − Furthermore, due to the use of carbon materials with high specific surface areas (up to 2500 m 2 /g), the amount of accumulated charge in ECs is several times higher compared to conventional electric and electrolytic capacitors. − For the above reasons, electrochemical capacitors and batteries are critical parts of power systems that are used in industry and everyday life.…”

“…All electrical energy storage devices, including ECs, deteriorate after some time with use, i.e., a gradual decline in their working parameters is observed. This is due to the destruction and degradation of the carbon electrode materials, current collectors, and separators, as well as the decomposition of the electrolyte solution. − ,− Undoubtedly, the main reason is the corrosion of the collectors, i.e., the stainless steel or metal elements responsible for conducting electric charge. This phenomenon is more pronounced if the electrolyte is aqueous.…”

From waste to energy storage: calcinating and carbonizing chicken eggshells into electrode materials for supercapacitors and lithium-ion batteries

“…At a lower scan rate, both supercapacitors exhibit typical capacitance for symmetric ECs with electrodes made of YP-80F in an aqueous electrolyte of 1 M Na 2 SO 4 , which falls around 109-125 F g −1 . 28,29 Comparison of the Fig. 3a and b show that the substitution of 10 wt% of YP-80F with OS 600 improves the long-term term and high-scan rate specic capacitance of the ECs, compared to the substitution with OS 900 .…”

Enhanced cycle life of starter lighting ignition (SLI) type lead–acid batteries with electrolyte modified by ionic liquid

“…A particularly large share is visible in chemical power sources. 28,29 In the case of lead-acid batteries, Rezaei et al found that different ammonium bisulphates affects the stability of the electrolyte and inhibits the phenomenon of electrochemical corrosion of current collectors. [16][17][18] Additionally, it has been shown that the observed effects depend on the concentration of the ionic liquid and the number of branches and length of alkyl substituents.…”