Reconfiguring Ion‐Transport Topology in Quasi‐Solid‐State Electrolytes for Cryogenic Lithium Metal Batteries

ABSTRACT

The growing demand for low‐temperature lithium metal batteries in aerospace, polar exploration, and other extreme environments calls for polymer electrolytes that can maintain efficient ion transport and interfacial stability under cryogenic conditions. Yet the low‐temperature application of polymer electrolytes is typically limited by the strong coupling of Li ⁺ transport to sluggish polymer segmental relaxation, leading to severe polarization, slow desolvation, and unstable electrode interphases. Here, we report an ion‐transport topology engineering strategy based on an in situ polymerized poly(1,3‐dioxolane) (PDOL) electrolyte. By introducing fluorobenzene (FB) as a hydrogen‐bond‐guided molecular organizer, we create a preorganized local transport field that weakens excessive Li ⁺ ‐ether oxygen coordination and reconfigures the local Li ⁺ migration landscape. This topology‐engineered microenvironment promotes anion‐rich coordination, lowers desolvation barriers, and directs inorganic‐rich interphase formation on both Li metal and high‐voltage cathodes. Consequently, the optimized electrolyte delivers a Li ⁺ transference number of 0.76 at −40°C and stable operation from −65 to 25°C. Li||Li cells cycle over 2000 h at −40°C, Li||LiNi _0.8 Co _0.1 Mn _0.1 O ₂ coin cells retain 99% capacity after 320 cycles, and pouch cells retain 84.9% after 450 cycles. This work establishes ion‐transport topology engineering as a viable design principle for polymer electrolytes under extreme‐temperature conditions.