An unnoticed inorganic solid electrolyte: dilithium sodium phosphate with the nalipoite structure

Area of Science:

• Materials Science
• Electrochemistry
• Solid-State Chemistry

Background:

• Solid electrolytes are essential for developing safer and more efficient advanced lithium batteries.
• Current lithium-ion battery technology faces limitations that advanced solid electrolytes could overcome.

Purpose of the Study:

• To investigate the potential of Li(3-x)Na(x)PO4 as a novel lithium-ion solid electrolyte.
• To synthesize and characterize orthorhombic Li2NaPO4 (nalipoite) and evaluate its ionic conductivity.
• To explore other potential crystal structures using computational methods.

Main Methods:

• Synthesis of orthorhombic Li2NaPO4 (nalipoite).
• Ionic conductivity measurements and comparison with Li3PO4.
• First-principles Density Functional Theory (DFT) calculations to explore crystal structure possibilities.

Main Results:

• Orthorhombic Li2NaPO4 (nalipoite) was successfully synthesized.
• The synthesized nalipoite exhibited highly favorable ionic conductivity compared to Li3PO4.
• The study provides the first investigation into Li(3-x)Na(x)PO4 as a lithium-ion solid electrolyte.

Conclusions:

• Li(3-x)Na(x)PO4 demonstrates significant potential as a solid electrolyte for advanced lithium batteries.
• The favorable ionic conductivity of nalipoite warrants further research and development.
• DFT calculations offer a pathway to discover new solid electrolyte materials.