Status and Challenges of Solid-State Electrolytes for Potassium Batteries

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Potassium solid-state batteries (K-SSBs) are emerging as a safe, high-energy-density solution for large-scale energy storage.
• Key challenges include limited solid-state potassium-ion electrolytes (K-SSEs) and interfacial instability.

Purpose of the Study:

• To review ion conduction mechanisms and parameters in K-SSEs.
• To highlight strategies for interface engineering in K-SSBs.
• To propose future research directions for K-SSB advancement.

Main Methods:

• Re-examination of ion conduction mechanisms in solid electrolytes.
• Review of inorganic and polymer K-SSEs for potassium-ion migration.
• Analysis of interface engineering techniques for K-SSBs.

Main Results:

• Electrolyte properties (crystal structure, composition, preparation) critically influence ionic conductivity and stability.
• Stable solid-electrolyte interphases and efficient cathode K⁺-ion transport are crucial for mitigating interfacial impedance.
• Strategic interface engineering enhances stable cycling performance in K-SSBs.

Conclusions:

• Advancing K-SSE performance and addressing interfacial issues are vital for K-SSB commercialization.
• Further research into electrolyte design and interface optimization is recommended.
• This review provides insights for developing high-performance K-SSEs and K-SSBs.