Micron-Sized Cobalt Niobium Oxide with Multiscale Porous Sponge-Like Structure Boosting High-Rate and Long-Life...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Niobium-based oxides are promising intercalation anodes for lithium-ion batteries (LIBs) due to high theoretical capacity.
• Poor electronic conductivity in these materials limits their electrochemical performance.

Purpose of the Study:

• To synthesize and evaluate micron-sized Co0.5Nb24.5O62 with a multiscale sponge-like structure as a fast-charging anode material for LIBs.
• To overcome the conductivity limitations of niobium-based oxides.

Main Methods:

• Synthesis of micron-sized Co0.5Nb24.5O62 with a multiscale sponge-like structure.
• Electrochemical characterization including capacity, rate capability, cycling stability, and Coulombic efficiency.
• Fabrication and testing of LiFePO4//Co0.5Nb24.5O62 full cells.

Main Results:

• The synthesized Co0.5Nb24.5O62 delivered a capacity of 287 mA h g-1 at 0.1C with a working potential of ~1.55 V vs Li+/Li and 91.1% initial Coulombic efficiency.
• Superior rate capability was observed, retaining 142 mA h g-1 at 10C.
• Excellent cycling stability was demonstrated with 75.3% capacity retention after 3000 cycles at 10C and a low volume change of 9.18%.

Conclusions:

• The multiscale porous sponge-like structure facilitates fast electronic/ionic transport, enhancing performance.
• Co0.5Nb24.5O62 is a promising fast-charging anode material for advanced lithium-ion batteries.
• Full cell tests confirmed the material's potential for practical applications in energy storage devices.