A non-Newtonian fluid quasi-solid electrolyte designed for long life and high safety Li-O₂ batteries

Li dendrite growth and liquid electrolyte volatilization under the semi-open architecture are intrinsic issues for Li-O₂ batteries. Here, a non-Newtonian fluid quasi-solid electrolyte (NNFQSE), SiO₂-SO₃Li/PVDF-HFP, exhibiting both shear-thinning and shear-thickening properties is proposed. Ion–dipole interactions among sulfonated silica nanoparticles, liquid electrolyte, and the PVDF-HFP polymer network enable decent Li⁺ conductivity and high liquid electrolyte retention with suppressed volatilization. The shear-thinning behavior eliminates stress from dendrite growth during cycling, while dynamic shear-thickening under sudden force (e.g., high current) mechanically stiffens the electrolyte to inhibit dendrite penetration. Coupled with NNFQSE, Li symmetric cells operate over 2000 h at 1 mA cm⁻² at room temperature, and quasi-solid Li–O₂ cells achieve lifetimes exceeding 5000 h at 100 mA g⁻¹.