Enhanced Lithium‐Ion Battery Electrodes with Metal–Organic Framework Additives Featuring Undercoordinated Zr ⁴⁺ Sites

Abstract

Abstract Performances of lithium‐ion batteries (LIBs) are dictated by processes of electron‐ion separation, transfers, and combination. While carbon additives are routinely used to ensure electronic conductivity, additives capable of simultaneously boosting ion conduction and delivering step‐change performance remain elusive. Herein, metal–organic frameworks (MOFs) possessing coordinately unsaturated Zr 4+ sites are exploited as a new material library of electrode additives. The MOFs imbue infused electrolytes with an expanded electrochemical stability window (0 to 5 V vs Li/Li⁺) and enhanced Li⁺ transport efficiency. Mechanistically, strong interactions between Zr 4+ sites and Li + solvation sheaths result in trimmed, anion‐fixed, and solvent‐separated ion pairs, mitigating electrostatic coupling and enabling efficient Li⁺ translocation in the porous nanospace. Concomitantly, these solvation structural modulations foster interfacial and electrochemical stabilities. When implemented at 1.7 wt.% in graphite and sub‐Ah full cell, the MOF additives significantly improved Li + diffusional kinetic, rate capability beyond 2C, and cycling longevity doubling lifespan. This work offers a straightforward yet effective route to remedy the bottlenecks of industrial LIBs.