Aqueous colloid flow batteries with nano Prussian blue.

Area of Science:

• Electrochemistry
• Materials Science
• Energy Storage

Background:

• Flow batteries offer safe and scalable energy storage for clean power.
• Carbon emissions reduction necessitates advanced energy storage solutions.
• Prussian blue (PB) is a promising redox-active material for electrochemical applications.

Purpose of the Study:

• To develop an aqueous colloid flow battery (ACFB) using Prussian blue (PB) nano-sized cubes.
• To explore novel nano redox materials for ACFB applications.
• To reduce the cost of chemicals in flow battery systems.

Main Methods:

• Synthesis of well-dispersed nano-sized Prussian blue (PB) cubes.
• Fabrication of an all-PB cell using a low-cost dialysis membrane.
• Assembly of a PB-based cell paired with an organic tetra pyridine macrocycle.
• Electrochemical cycling and stability testing of the redox-active colloids.

Main Results:

• An all-PB cell achieved an open-circuit voltage (OCV) of 0.74 V.
• A PB-based cell paired with a macrocycle reached an OCV of 1.33 V.
• The cell exhibited a low capacity fade rate of 0.039 %/cycle (0.8 %/day).
• Redox-active colloids showed excellent physicochemical stability with no structural changes after cycling.

Conclusions:

• Nano-sized Prussian blue cubes are effective redox materials for ACFB.
• The developed ACFB technology offers a cost-effective and reliable energy storage solution.
• PB-based ACFB holds potential for large-scale clean energy storage applications.