Bulk-to-interface engineering of solid-state electrolytes toward fast-charging Li/Na-ion batteries

From the invention of electric vehicles to their widespread application in fields such as smart grids, communication technology, bio-implants, and wearable devices, the development of lithium-ion and sodium-ion batteries has placed higher demands on fast-charging technologies. Solid-state electrolytes have become a crucial step toward achieving fast-charging due to their outstanding safety and high energy density, but related technologies still require further breakthroughs. This review illustrates the advantages of solid-state electrolytes as the basis for fast-charging in lithium-ion and sodium-ion batteries. In addition, it delves into the ionic conductivity and ion flux in the bulk phase of solid-state electrolytes, along with thermodynamic, kinetic, and mechanical properties at the interface. The discussion also encompasses corresponding optimization strategies and evaluation systems. Different viewpoints on dendrite formation and battery short circuits are supplemented, and the modes on static and dynamic surface failure at the solid electrolyte interface are distinguished for the first time. Lastly, the review presents an integrated process aimed at further enhancing the energy density of lithium-ion and sodium-ion batteries while optimizing their fast-charging capabilities at the bulk-to-interface engineering.