Carving Metal-Organic-Framework Glass Based Solid-State Electrolyte Via a Top-Down Strategy for Lithium-Metal Battery

Angew Chem Int Ed Engl. 2025 Jan 20:e202424288. doi: 10.1002/anie.202424288. Online ahead of print.

Abstract

Traditional polymer solid electrolytes (PSEs) suffer from low Li conductivity, poor kinetics and safety concerns. Here, we present a novel porous MOF glass gelled polymer electrolyte (PMG-GPE) prepared via a top-down strategy, which features a unique three-dimensional interconnected graded-aperture structure for efficient ion transport. Comprehensive analyses, including time-of-flight secondary ion mass spectrometry (TOF-SIMS), Solid-state 7Li magic-angle-spinning nuclear magnetic resonance (MAS-NMR), Molecular Dynamics (MD) simulations, and electrochemical tests, quantify the pore structures, revealing their relationship with ion conductivity that increases and then decreases as macropore proportion rises. The introduced dispersed macropores (17% fraction) can serve as bridges, connecting adjacent transport units to accelerate ion transport. Taking advantage of the cross-linked ion-conductive paths constructed by hierarchical pore structure, the PMG-GPE achieves a high ionic conductivity of 1.9 mS cm-1. Additionally, the robust mechanical properties of PMG-GPE effectively suppress dendrite growth and penetration, outperforming crystal MOF-based electrolytes. The prepared Li symmetric batteries with PMG-GPE demonstrate a high critical current density of 5.1 mA cm-2 (two times higher than crystal MOF-electrolytes) and stable cycling for over 6000 hours without short circuits. Furthermore, a Li/PMG-GPE/LFP half-cell exhibits exceptional capacity retention of 83.12% after 1400 cycles.

Keywords: Li metal battery; MOFs glass; graded-aperture structure; ion conductivity; polymer solid state electrolyte.