Review: recent progress in the inhibition of metal dendrites in sodium/potassium ion batteries

Sodium-ion batteries (SIBs) and potassium-ion batteries (PIBs) have emerged as promising alternatives to lithium-ion batteries (LIBs) due to the abundance and cost-effectiveness of sodium and potassium resources. However, the growth of metal dendrites on sodium/potassium anodes poses significant safety and performance challenges. This review systematically summarizes recent advancements in suppressing dendrite formation through electrolyte optimization, artificial solid electrolyte interphase (SEI) engineering, and nanostructured electrode design. For sodium metal anodes, strategies such as high-concentration electrolytes (e.g., NaFSI-DME), fluoroethylene carbonate (FEC) additives, and 3D porous frameworks (e.g., carbonized wood or MXene hybrids) have demonstrated enhanced Coulombic efficiency (> 99%) and dendrite-free cycling stability. Similarly, potassium metal anodes benefit from surface modifications (e.g., graphene-coated collectors), alloy-based protective layers (e.g., K-Hg), and optimized ionic liquid electrolytes, achieving stable operation at high current densities (20 mA cm⁻²). The review also highlights the role of solid-state and polymer electrolytes in improving interfacial stability and mechanical robustness. Despite progress, challenges remain in balancing ionic conductivity, interfacial compatibility, and scalability. Future directions emphasize co-optimizing SEI/cathode-electrolyte interphases, leveraging advanced materials (e.g., biomass-derived carbons, MXenes), and integrating computational modeling to accelerate the development of high-energy–density, safe SIBs/PIBs for grid storage and electric vehicles.

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