Direct Solution-Based Synthesis of Na₄ (B₁₂ H₁₂ )(B₁₀ H₁₀ ) Solid Electrolyte.

Area of Science:

• Materials Science
• Electrochemistry
• Solid-state Chemistry

Background:

• All-solid-state batteries (ASSBs) offer superior energy and power density compared to liquid electrolyte batteries.
• A stable 3V ASSB utilizing the superionic conductor Na4(B12H12)(B10H10) has shown remarkable cycling stability.

Purpose of the Study:

• To develop a scalable, solution-based synthesis for the Na4(B12H12)(B10H10) superionic conductor.
• To enable cost-efficient production of key precursors (Na2B10H10 and Na2B12H12) via a wet chemistry approach.
• To investigate reaction mechanisms and identify key parameters for optimizing synthesis.

Main Methods:

• A five-step, solution-based wet chemistry approach was employed for synthesis.
• Investigated reaction mechanisms to understand synthesis pathways.
• Identified the influence of counter cation (tetraethylammonium) and solvent on reaction kinetics and selectivity.

Main Results:

• Achieved a scalable and cost-effective synthesis of Na4(B12H12)(B10H10) using wet chemistry.
• Demonstrated high-throughput solution processing, addressing limitations in electrode-electrolyte contact.
• Successfully synthesized expensive precursors (Na2B10H10 and Na2B12H12) cost-efficiently.

Conclusions:

• The developed wet chemistry method provides a viable route for large-scale production of Na4(B12H12)(B10H10) for ASSBs.
• This approach enhances the practical applicability of ASSBs by improving manufacturing efficiency and reducing costs.
• Understanding the role of counter cation and solvent is crucial for optimizing the synthesis of advanced solid electrolytes.