A kind of aqueous mixed electrolyte and its application in zinc ion hybrid supercapacitor

Abstract

The invention relates to an aqueous mixed electrolyte and its application in a zinc ion mixed supercapacitor. Disclosed is a mixed electrolyte comprising an organic zinc salt as a solute and water and ethylene glycol as a solvent, which has an ion conductivity comparable to that of an aqueous solution and a lower freezing point (<‑20°C). The interaction between ethylene glycol and the anions in the organic zinc salt changes the solvation state of the zinc ions in the mixed electrolyte, reduces the electron cloud density of hydrogen in the hydration structure of the zinc ions, effectively inhibits the hydrogen evolution reaction, broadens its potential window, and slows down the production of water-based batteries. Effect of gas on cycle stability. The adsorption of zinc ions on the surface of activated carbon is enhanced, and a faster and more efficient adsorption-desorption reaction can occur on the surface of activated carbon, which improves the specific capacity of the hybrid supercapacitor. The introduction of ethylene glycol and organic zinc salt can greatly increase the conductivity of the mixed electrolyte at low temperature, thereby increasing the power density of the hybrid supercapacitor at low temperature, thereby broadening its operating temperature and application range.

Description

An aqueous mixed electrolyte and its application in zinc ion hybrid supercapacitors technical field The present invention relates to the field of electrochemical energy storage, particularly a kind of water-based mixed electrolyte and its zinc ion mixed ultra-high applications in grade capacitors. Background technique [0002] With the development of intelligent electronic equipment, electric vehicles and other fields, people are concerned about the energy density, fast charging of energy storage equipment. The requirements for discharge performance and safety performance are getting higher and higher. Zinc-ion secondary battery is a new type of high-efficiency rechargeable battery. source rich zinc (theoretical specific capacity is 823mAh g -1 ) instead of lithium sodium as the negative electrode material, not only the preparation process is simple, the battery material It is non-toxic and inexpensive, the discharge process is safe, and it has high energy density...

AI Technical Summary

Problems solved by technology

However, due to the high freezing point of water, the system cannot operate at lower temperatures. Adding organic solvents and using organic zinc salts as solutes to construct a mixed electrolyte with a low freezing point is essential for improving the low-temperature performance of zinc-ion hybrid supercapacitors. important

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