A kind of preparation method of electric field activated supercapacitor

Abstract

The invention discloses a method for preparing electric field activation type super capacitors. According to the method, electrode active material is respectively mixed with adhesive and conductive agent evenly, graphite-like material electrode pieces are manufactured on the surface of a metal collector electrode by utilization of the mixture, the manufactured graphite-like electrode pieces are used as positive electrodes and negative electrodes of electrodes of the capacitors, separating membranes are adopted to separate the electrodes, ionic liquid with molecular weight equal to or smaller than 500 is used as electrolyte to assemble the capacitors, electric field activation is performed, and the electric field activation type super capacitors are manufactured. A potential window of the electrolyte of the super capacitors is wide, and rated working voltage of the capacitors is improved; the electrolyte is small in molecular volume, and inserting embedding-emigrating out can be performed among graphite layers under the condition of the electric field activation; electrochemical performance of the electrolyte is stable, the electric field activation can be performed under the condition of high voltage, electrolyte ions can be fully inserted and embedded among the graphite layers, and high-inserting-layer electrostatic capacitors are obtained.

Description

technical field [0001] The invention relates to a preparation method of an electric field activated supercapacitor. Background technique [0002] Supercapacitor is a new type of green energy storage element, which has the characteristics of good power performance, fast charging and discharging, long cycle life and wide operating temperature range. However, supercapacitors have the defect of low energy density, which restricts their large-scale application in energy storage such as electric vehicles, photovoltaic power generation and wind power generation. [0003] The energy density of the supercapacitor ( E =1 / 2 CU 2 , C is the specific capacitance, U is the rated working voltage) depends on the properties of the electrode active material and electrolyte. The electric field activated capacitor is based on a certain layer spacing (d 002 ) The graphite material is in contact with the electrolyte, and when a voltage above the normal operating voltage is applied, the ele...

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Problems solved by technology

Its disadvantages are: 1. The potential window of the non-closed structure quaternary ammonium salt organic solvent electrolyte is narrow, and the rated working voltage of the capacitor is low; 2. The volume of the solvated non-closed structure quaternary ammonium salt is relatively large, and it is difficult to be separated between the graphite layers under the condition of electric field activation. Intercalation-migration; 3. The electrochemical stability of non-closed quaternary ammonium salts is poor, and electric field activation under higher voltage conditions cannot be achieved. The intercalation of electrolyte ions between graphite layers is insufficient, and it is difficult to obtain high intercalation. Electrostatic capacitance

The disadvantages are: 1. The solvated electrolyte ion has a large ionic radius, which is not conducive to its intercalation-migration between graphite layers; 2. Organic solvents are easy to polymerize under high electric field activation voltage, and the formation of ions on the graphite surface Polymer film blocks the pore diameter of the electrode active material, reduces the specific capacitance of the capacitor, decreases the charge and discharge efficiency, and increases the internal resistance

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