Sulfide All-Solid-State Battery with Ultrahigh Nickel Layered Oxide Cathode and Capacity

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Nickel-rich layered oxide cathodes are crucial for high-performance sulfide all-solid-state batteries (SASSBs).
• Interfacial issues like space charge layers, elemental diffusion, and poor contact impede SASSB performance by increasing impedance.

Purpose of the Study:

• To address interfacial impedance in SASSBs using nickel-rich layered oxide cathodes.
• To enhance ionic conductivity, Li+ migration, and mechanical stability of the cathode surface.

Main Methods:

• A hybrid coating of lithium phosphorus oxide (LPO) and lithium boron oxide (LBO) was designed for a 95% nickel (Ni) content NCM cathode.
• Fabrication and testing of SC-NCM92@LPO+LBO and SC-NCM95@LPO+LBO based SASSBs using Li6PS5Cl solid electrolyte and Li-In alloy anode.

Main Results:

• The hybrid coating improved ionic conductivity and Li+ migration efficiency.
• SC-NCM92@LPO+LBO SASSBs achieved a specific discharge capacity of 220.5 mAh g-1 with good high-rate performance.
• SC-NCM95@LPO+LBO SASSBs demonstrated a high specific capacity of 253.3 mAh g-1, excellent high-rate capability (137.9 mAh g-1 at 10C), and superior cycling stability.

Conclusions:

• The LPO+LBO hybrid coating effectively mitigates interfacial impedance and enhances electrochemical performance in SASSBs.
• This strategy provides a valuable reference for applying ultrahigh nickel-layered oxide cathodes in SASSBs, paving the way for advanced energy storage solutions.