Active carbon/graphene composite electrode electrical double-layer capacitor and preparation method thereof

Abstract

The invention relates to an active carbon / graphene composite electrode electrical double-layer capacitor and a preparation method thereof. The method comprises the following steps of: S1, preparing electrode slurry, namely mixing and stirring an electrode active material, carbon black, an organic binder and a solvent to obtain homogeneous slurry, and dispersing the homogeneous slurry for 1 hour by using an ultrasonic cleaning machine to disperse graphene particles in the slurry, the electrode active material comprising graphene and active carbon with the specific surface area larger than 1190 m<2>g<-1>; S2, coating an aluminum foil current collector with the electrode slurry; S3, preparing an organic electrolyte: mixing and stirring an organic solvent and an organic salt at 50 DEG C for 2 hours to obtain a clear electrical double-layer capacitor organic electrolyte; and S4, assembling an electrical double-layer capacitor. Compared with a common electrical double-layer capacitor, the electrical double-layer capacitor has the advantages that the specific capacitance, the energy density and the charging / discharging duration can be improved, the internal resistance is reduced, and an energy storage device can be light.

Description

technical field [0001] The invention belongs to the technical field of energy storage, and in particular relates to an electric double-layer capacitor with activated carbon / graphene composite electrodes and a preparation method thereof. Background technique [0002] Supercapacitors have attracted extensive attention due to their high power density, high charge / discharge rate and long cycle life performance. They are considered to be one of the most promising electrochemical energy storage devices, with the potential to complement or eventually replace batteries used for energy storage in wearable and portable electronics, electric and hybrid vehicles. Based on the energy storage mechanism, supercapacitors can be divided into two categories, namely, electric double layer capacitors (EDLCs) and pseudocapacitors. For EDLCs, capacitance arises from the accumulation of charge at the electrode-electrolyte interface. Therefore, controlling the electrode specific surface area and ...

AI Technical Summary

Problems solved by technology

However, the actual capacitive performance of pure graphene is lower than expected due to severe agglomeration during preparation and application

Therefore, improving the overall electrochemical performance of graphene-based materials remains a great challenge.

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