Spherical V₂O₅/C Cathode Materials Prepared by Spray Drying for High-Power Thermal Batteries

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Commercial vanadium pentoxide (V2O5) powders have lamellar structures, limiting stability and ion/electron transport in thermal batteries.
• This restricts the discharge performance of V2O5 cathodes, necessitating improved material design.

Purpose of the Study:

• To enhance the discharge performance of V2O5 cathodes for thermal batteries.
• To achieve this by creating a robust spherical architecture using spray drying and carbon modification.

Main Methods:

• Fabrication of spherical V2O5/C composite cathode material using scalable spray drying.
• Incorporation of a conductive carbon network to improve electron transport.
• Characterization of electrochemical performance, including initial discharge voltage, specific capacity, and energy density at high temperatures.
• Analysis of structural integrity and interfacial resistance using pulse discharge tests.

Main Results:

• The V2O5/C cathode exhibited a high initial discharge voltage of 2.45 V.
• Achieved a specific capacity of 261.06 mAh g-1 and energy density of 591.05 Wh kg-1 at 0.1 A cm-2 and 500 °C.
• Demonstrated enhanced voltage stability and reduced interfacial resistance compared to commercial V2O5.
• The spherical architecture and carbon network improved electron/ion transport and structural integrity.

Conclusions:

• The developed spherical V2O5/C cathode significantly enhances thermal battery discharge performance.
• The synergistic effect of morphology and carbon modification is key to improved conductivity and stability.
• This scalable strategy offers a pathway for high-performance V2O5 cathodes in thermal batteries.