LiNi_0.5Mn_1.5O₄ Cathode Microstructure for All-Solid-State Batteries

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Solid-state batteries (SSBs) offer higher energy density and safety than Li-ion batteries.
• Practical SSBs face challenges like capacity decay due to poor electrode contact.
• LiNi0.5Mn1.5O4 (LNMO) is a promising cathode material for high-voltage SSBs.

Purpose of the Study:

• Investigate the impact of cathode microstructure on SSB performance.
• Design and synthesize Al2O3-coated LNMO with a hollow structure.
• Improve cathode utilization and cycling stability in SSBs.

Main Methods:

• Synthesized Al2O3-coated hollow LNMO particles.
• Fabricated SSB cells using Li6PS5Cl solid electrolyte.
• Performed electrochemical cycling tests to evaluate capacity retention and stability.

Main Results:

• Demonstrated improved cycling stability with the hollow LNMO cathode.
• Achieved over 70% capacity retention after 100 cycles.
• Showcased high active material loading (27 mg cm-2) at 0.8 mA cm-2.

Conclusions:

• Cathode microstructure is critical for SSB performance.
• Hollow, coated LNMO particles enhance electrolyte stability and Li+ diffusion.
• This approach offers a pathway to practical, high-performance solid-state batteries.