In situ polymerized LATP/PAN-reinforced solid-state electrolyte for stable lithium-metal batteries

The flammable liquid electrolyte (LE) in lithium metal batteries continuously undergoes side reactions with lithium metal, not only consuming active substances but also potentially triggering thermal runaway, thereby limiting the practical viability of these high-energy-density systems ¹. Solid polymer electrolytes (SPEs), with their high flexibility, good interface compatibility with electrodes, and advantages in production processes, have established themselves as essential candidate materials for energy storage solutions. Herein, we designed a composite solid electrolyte (designated L-PAN-D) using polyethylene glycol diacrylate (PEGDA) as the polymerizable monomer, via in-situ deposition polymerization. This electrolyte achieves a maximum ionic conductivity of 0.694 mS cm⁻¹ and an electrochemical window of 5.1 V. Notably, the assembled Li/LFP and Li/NCM811 full cells retained 95.2% and 88.4% of their initial capacities respectively after 200 cycles at 1C, manifesting excellent cycling stability. This work provides valuable insights for the in-situ deposition fabrication of solid electrolytes.