Highly conductive colloidal carbon based suspension for flow-assisted electrochemical systems

Area of Science:

• Electrochemistry
• Materials Science
• Energy Storage

Background:

• Flow-assisted electrochemical systems like flow batteries and capacitors require specialized electrodes.
• Developing stable carbon suspensions with both low viscosity and high conductivity is a significant challenge.
• Existing carbon suspensions often compromise performance due to suboptimal rheological and electrical properties.

Purpose of the Study:

• To engineer a high-performance, flowable aqueous carbon dispersion for electrochemical energy storage.
• To achieve a balance between low viscosity and high electronic conductivity in carbon suspensions.
• To demonstrate the efficacy of the developed carbon dispersion in flowable electrochemical systems.

Main Methods:

• Formulation of aqueous carbon dispersions using sodium alginate and arabic gum as stabilizers.
• Addition of ammonium sulfate to enhance suspension properties.
• Characterization of rheological properties (viscosity at specific shear rates) and electronic conductivity.
• Testing the dispersion in flowable systems for electrical charge storage and discharge.

Main Results:

• A stable aqueous carbon dispersion was successfully created with a viscosity of 2 Pa.s at 7 wt% particle concentration and a shear rate of 5 s⁻¹.
• The dispersion achieved an electronic conductivity of 65 mS/cm, significantly higher than previous materials.
• The material demonstrated effective performance in flowable systems for electrochemical charge storage and discharge.

Conclusions:

• The developed carbon dispersion offers a promising solution for flow-assisted electrochemical energy storage.
• The formulation overcomes key challenges by combining low viscosity with high electronic conductivity.
• This advancement has implications for improving the efficiency and applicability of flow batteries, flow capacitors, and capacitive deionization.