Enhanced the interfacial compatibility by lithium anode of DOL-based in-situ polymerized gel polymer electrolytes with addition of silicon nanoparticles

Gel polymer electrolytes (GPEs) prepared by in situ polymerization have attracted increasing interests recently because of the combined advantages of liquid and solid-state electrolytes. However, the uncontrolled growth of lithium dendrites still limits the further development of GPE in solid-state batteries. Here, we add a certain amount of Si nanoparticles into the precursor solution, which are immobilized in GPEs during the in-situ polymerization of DOL. It is found the GPE with 0.75 % Si nanoparticles exhibits the highest conductivity and lithium-ion transfer number (tLi+) of 0.711. As a result, the Li/Li symmetric cell using such GPEs achieves uniform plating/exfoliation of Li for 1000 h, and the LiFePO4/Li cell delivers stable capacities of 155.4 mA h g−1 after 100 cycles at 0.1C and 142.6 mA h g−1 after 200 cycles at 0.5C respectively. Moreover, an assembled LFP/PDOL-0.75 % Si/(Si/C) full cell delivers a reversible capacity of 122 mA h g−1 after 30 cycles at 0.1C. This research provides an effective avenue to construct stable and safe GPEs for solid-state batteries.