Stabilizing Micro-Sized Silicon Oxides by Durable Hydrogen Chemistry

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Micro-sized silicon oxide (µSiOₓ) is a promising anode material for high-energy lithium batteries due to its low cost and high capacity.
• Instability of the solid electrolyte interphase (SEI) on µSiOₓ anodes leads to irreversible lithium consumption and electrolyte decomposition, hindering long-term stability.

Purpose of the Study:

• To enhance the stability of the solid electrolyte interphase (SEI) on micro-sized silicon oxide (µSiOₓ) anodes.
• To improve the long-term cycling performance and capacity retention of µSiOₓ anodes for lithium batteries.

Main Methods:

• Utilizing the dual functionality of hydrogen chemistry for interface regulation and atmospheric protection.
• Employing highly reversible hydrogen evolution and oxidation redox reactions to stabilize the anode surface.

Main Results:

• Achieved a discharge capacity of ~1568 mAh g⁻¹ at 1 C with a charge capacity of 1600 mAh g⁻¹.
• Demonstrated stable cycling for 2000 hours with ~98% Coulombic efficiency at a charge capacity of 700 mAh g⁻¹.
• Maintained discharge capacity at ~2.93 mAh cm⁻² after 600 hours of cycling at a high areal capacity of 3 mAh cm⁻².

Conclusions:

• The hydrogen chemistry-based strategy effectively enhances SEI stability on µSiOₓ anodes.
• This approach offers a viable solution for stabilizing high-capacity µSiOₓ anodes, advancing their practical application in lithium batteries.