Series module of quinone-based organic supercapacitor (>\u20096\xa0V) with practical cell structure

Yuto Katsuyama,Shu Sokabe,Hiroya Abe,Mizuki Ishizawa,Masaru Watanabe,Yuta Nakayasu,Takayuki Takehi,Mai Tanaka,Itaru Honma

doi:10.1038/s41598-022-07853-6

Abstract

Inexpensive, high-performing, and environmentally friendly energy storage devices are required for smart grids that efficiently utilize renewable energy. Energy storage devices consisting of organic active materials are promising because organic materials, especially quinones, are ubiquitous and usually do not require harsh conditions for synthesis, releasing less CO2 during mass production. Although fundamental research-scale aqueous quinone-based organic supercapacitors have shown excellent energy storage performance, no practical research has been conducted. In this study, we aimed to develop a practical-scale aqueous-quinone-based organic supercapacitor. By connecting 12 cells of size 10 cm × 10 cm × 0.5 cm each in series, we fabricated a high-voltage (> 6 V) aqueous organic supercapacitor that can charge a smartphone at a 1 C rate. This is the first step in commercializing aqueous organic supercapacitors that could solve environmental problems, such as high CO2 emissions, air pollution by toxic metals, and limited electricity generation by renewable resources.

Highlights

Renewable energy generated approximately 21% of all the electricity in the United States in 2020, the secondlargest power generation following natural g as[1]
Organic compounds are often synthesized under mild conditions from renewable resources, which does not require a huge amount of energy for mass production as inorganic materials d o7,10,11,14–16
At the fundamental research scale, a beaker and gold mesh are used for the cell container and current collector, respectively, which are strong against acidic solutions

Summary

Introduction

Renewable energy generated approximately 21% of all the electricity in the United States in 2020, the secondlargest power generation following natural g as[1]. Especially quinones, have two redox centers in a single molecule, leading to a high capacity of up to 496 mAh g–1 Their redox potentials are adjustable in the range of 1.7–3.2 V vs Li/Li+ by molecular engineering[18,19]. One effective method is to impregnate quinones in the micropores of porous carbon materials to provide conductive paths and suppress the dissolution of quinones into the electrolyte[21,23,24,26] By using this strategy, a full-cell redox supercapacitor with a tetrachlorohydroquinone (TCHQ) cathode and a dichloroanthraquinone (DCAQ). It should be verified that the practical-size electrodes with sufficient mass loadings still show capacities and voltages comparable to those of the fundamental research-scale electrodes Another problem is that this type of redox supercapacitor uses acidic aqueous electrolytes (e.g., 0.5 M H2SO4 aq.), which requires the use of acid-durable materials for cell components. We believe that the knowledge obtained from this study will promote research on practical applications of aqueous organic supercapacitors, which has been lacking but is essential and must be tackled simultaneously with fundamental research

Objectives

Methods

Results

Conclusion