Impact-Tolerant Batteries Enabled by High-Conductivity Shear Thickening Electrolytes.

The application of shear thickening electrolytes (STEs) in batteries is hindered by the conventional trade-off, in which enhanced impact resistance comes at the cost of reduced ionic conductivity. Here, we overcome this barrier by introducing lithium sulfonate-functionalized mesoporous silica (M-SiO2-SO3Li) as a multifunctional filler. Unlike conventional fillers that impede ion transport, M-SiO2-SO3Li simultaneously induces shear thickening and enhances conductivity. At 15 wt.% loading, the electrolyte achieves a remarkable ionic conductivity of 10.73 mS cm-1, higher than that of filler-free traditional electrolytes (TE), by anchoring anions via the -SO3Li groups to increase the Li+ transference number. This synergy enables exceptional battery performance: Li||LFP cells demonstrate 97.0% capacity retention after 500 cycles, and LFP||Gr pouch full cells maintain 83.8% capacity after 200 cycles at 0.5 C. In impact tests, the robustness of this design is evident as the M-SiO2-SO3Li-based pouch cell withstands hammer drops that cause immediate failure in standard TE cells. Thus, this design strategy overcomes the performance trade-off, integrating high conductivity, long cycling life, and impact resistance, and provides a pathway for application across the liquid-based electrolyte family.