Lithium-ion transport through a tailored disordered phase on the LiNi0.5 Mn1.5 O4 surface for high-power cathode...

Area of Science:

• Materials Science
• Electrochemistry
• Solid-State Chemistry

Background:

• Spinel lithium nickel manganese oxide (LiNi0.5 Mn1.5 O4) is a promising cathode material for high-power applications.
• Enhancing lithium-ion (Li+) diffusion kinetics is crucial for improving the electrochemical performance of LiNi0.5 Mn1.5 O4.

Purpose of the Study:

• To control the phase of spinel LiNi0.5 Mn1.5 O4 through surface modification.
• To enhance the electrochemical properties of LiNi0.5 Mn1.5 O4 by improving Li+ transport.

Main Methods:

• Surface treatment of LiNi0.5 Mn1.5 O4 via phosphidation.
• Characterization of the resulting disordered phase (Fd3m) structure.
• Electrochemical performance testing at high charge/discharge rates (exceeding 10 C).

Main Results:

• Phosphidation successfully modified the surface structure of LiNi0.5 Mn1.5 O4 into a disordered phase.
• The disordered phase facilitated facile Li+ transport within the spinel structure.
• Phosphidated LiNi0.5 Mn1.5 O4 exhibited significantly enhanced electrochemical performance, particularly at high rates.

Conclusions:

• Surface phosphidation is an effective strategy for controlling the phase and improving the electrochemical properties of LiNi0.5 Mn1.5 O4.
• The enhanced kinetics, linked to increased Mn(3+) content, position LiNi0.5 Mn1.5 O4 as a viable high-power cathode material.
• This advancement supports the use of LiNi0.5 Mn1.5 O4 in electric vehicles and hybrid electric vehicles.