High-discharge-voltage lithium-rich layered-oxide cathode materials based on low oxygen vacancy

Area of Science:

• Materials Science
• Electrochemistry
• Inorganic Chemistry

Background:

• Lithium-rich layered oxides are promising cathode materials for high-energy-density lithium-ion batteries.
• Achieving high and stable discharge voltages is crucial for enhancing battery performance.
• Understanding the role of defects, such as oxygen vacancies, is key to optimizing material properties.

Purpose of the Study:

• To synthesize a novel lithium-rich layered oxide, Li$_{1.2}$Mn$_{0.54}$Co$_{0.13}$Ni$_{0.13}$O$_{2}$.
• To achieve a high average discharge voltage of 3.65 V.
• To investigate the influence of oxygen vacancies on the discharge voltage characteristics.

Main Methods:

• Synthesis of Li$_{1.2}$Mn$_{0.54}$Co$_{0.13}$Ni$_{0.13}$O$_{2}$ using a lithiated homologous spinel precursor (Li$_{0.4}$Mn$_{0.54}$Ni$_{0.13}$Co$_{0.13}$O$_{1.6}$).
• Preparation conducted under an oxygen atmosphere (O$_{2}$).
• Electrochemical testing to determine average discharge voltage.
• Analysis of oxygen vacancy effects on electrochemical properties.

Main Results:

• Successfully synthesized the target lithium-rich layered oxide material.
• Achieved a high average discharge voltage of 3.65 V.
• Demonstrated a correlation between oxygen vacancies and the observed discharge voltage.

Conclusions:

• The developed synthesis method is effective for producing high-performance lithium-rich layered oxides.
• The material exhibits potential for high-voltage applications in lithium-ion batteries.
• Control over oxygen vacancies is a viable strategy for tuning the electrochemical properties of these materials.