Tailoring the surface energy and area surface resistance of solid-electrolyte polymer membrane for dendrite free, high-performance, and safe solid-state Li-batteries

Solid electrolyte polymer composite enabled solid-state lithium batteries have shown extensive viability for mass production and commerciality for advanced energy storage technology. Most studies of polymer composite electrolyte are produced by solution casting and free-standing methods, where ionic conductors are randomly distributed into the polymeric network, suffering from poor ionic conductivity and agglomeration during charge/ discharge cycling. In this work, using the threshold percolation model and critical volume fraction requirement, we have designed a highly efficient garnet-type ion-conducting nanofibrous sheet where ionic conductors of different aspect ratios are dispersed to tune the surface roughness, area surface resistance, and wettability of the developed electrolyte membrane. Moreover, the impact of filler volume fraction and percolation threshold on the surface properties of the membrane, regulating the area interfacial resistance of the Li metal cell has also been examined, which has not been studied so far in the literature. The corresponding high potential cathode-based lithium assembled coin cells exhibit an excellent specific capacity of 170 mAh g-1 at 0.3C, with high capacity retention under ambient circumstances. By optimizing the critical aspect ratio of the fillers and the percolation threshold, a high-performing solid electrolyte membrane can be realized for advanced and safer Li-batteries technology.