Combination of Organic and Inorganic Electrolytes for Composite Membranes Toward Applicable Solid Lithium Batteries

To meet the demand for long-range electric vehicles with high-energy-density batteries, the solid-state batteries(SSBs) have attracted ever-increasing attention due to their enormous potential in affording the energy density greater than 400 W·h/kg. As the key materials, the solid electrolytes can be classified as inorganic electrolyte and organic electrolyte. The former usually has high ionic conductivity, good stability and mechanical properties, whereas being heavy and brittle. The latter is usually flexible, light and easy to mass produce, nevertheless has poor ionic conductivity and stability. Thus, the combination of the organic and the inorganic electrolytes for the composite membranes has become the inevitable trend to achieve the high energy density and safety of lithium batteries. From the perspective of practical application, this paper discusses how to construct the ideal organic-inorganic composite solid electrolyte with low areal specific resistance, thin texture, wide electrochemical window and high safety for applicable SSBs. Furthermore, the critical challenges and future development directions are prospected for the composite solid electrolytes.