Controlling Surface Structure and Primary Particle Size to Enhance Performance and Reduce Gas Evolution in Lithium-...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Lithium- and manganese-rich layered oxide cathodes offer high performance and low cost but suffer from gas evolution and capacity loss.
• This gas evolution issue hinders their practical application, even within conservative operating voltage windows.

Purpose of the Study:

• To enhance the electrochemical performance of lithium- and manganese-rich layered oxide cathodes.
• To mitigate gas evolution during battery operation.
• To make these cathodes competitive with conventional high-nickel alternatives.

Main Methods:

• Controlled surface structure using sulfur-coated Fm3̅m/R3̅m double reduced surface layers.
• Modified primary particle size.
• Incorporated Molybdenum (Mo) doping.

Main Results:

• Dramatically reduced gas evolution.
• Significantly improved electrochemical performance.
• Achieved performance competitive with high-nickel cathodes in a 2.5-4.4 V window regarding gas evolution and electrochemical metrics.

Conclusions:

• Surface structure and particle size engineering are crucial for improving lithium- and manganese-rich layered oxide cathodes.
• Sulfur coating and Mo doping effectively suppress gas evolution.
• Optimized cathodes demonstrate viability for practical energy storage applications.