Co-activation for enhanced K-ion storage in battery anodes

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Potassium-ion batteries (KIBs) are promising for large-scale energy storage due to potassium's abundance and high theoretical energy density.
• Current KIB anode limitations include low capacity and high discharge plateaus, hindering practical energy density and development.

Purpose of the Study:

• To investigate a co-activation mechanism between bismuth (Bi) and tin (Sn) to enhance potassium-ion storage in battery anodes.
• To develop a high-performance anode material for efficient and stable KIBs.

Main Methods:

• Fabrication and electrochemical characterization of a co-activated bismuth-tin (Bi-Sn) anode.
• Testing of the anode's capacity, discharge plateau, cycling stability, and Coulombic efficiency in a KIB setup.

Main Results:

• The Bi-Sn anode exhibited a high capacity of 634 mAh g⁻¹.
• A low discharge plateau of 0.35 V was achieved, contributing to higher energy density.
• The anode demonstrated excellent stability, operating for 500 cycles with 99.2% Coulombic efficiency at 50 mA g⁻¹.

Conclusions:

• The co-activation of Bi and Sn offers a viable strategy for improving potassium storage performance in battery anodes.
• This approach provides valuable insights for enhancing energy storage capabilities in various ion battery technologies (Na, Zn, Ca, Mg, Al).