An Active-Oxygen-Scavenging Oriented Cathode-Electrolyte-Interphase for Long-Life Lithium-Rich Cathode Materials.

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Lithium-rich layered oxides offer high energy density for next-generation batteries.
• Commercialization is hindered by lattice oxygen release at high voltages, causing electrolyte decomposition and capacity fade.
• Stabilizing the cathode-electrolyte interface (CEI) is critical for performance.

Purpose of the Study:

• To investigate the use of β-carotene as an antioxidant additive in electrolytes for lithium-rich cathodes.
• To mitigate issues related to active oxygen release and electrolyte degradation.
• To enhance the electrochemical stability and cycle life of lithium-rich battery systems.

Main Methods:

• Utilized β-carotene, an antioxidant molecule, as an electrolyte additive.
• Analyzed the in situ formation of a protective cathode-electrolyte interface (CEI) layer.
• Evaluated electrochemical performance, including cycle stability and capacity retention, under high voltage conditions.

Main Results:

• Controlled active oxygen species release, significantly reducing carbonate electrolyte decomposition.
• Formed a robust, double-layer CEI with both organic and inorganic components.
• Achieved excellent long-life cycle stability with 93.4% capacity retention after 200 cycles at 1 C.
• Demonstrated superior electrochemical stability compared to other electrolyte additive systems.

Conclusions:

• β-carotene effectively scavenges active oxygen, protecting lithium-rich cathodes.
• The in situ generated CEI layer enhances battery stability and longevity.
• This approach offers a promising strategy for commercializing high-energy-density lithium-rich cathode materials.