Zwitterionic-polymer-intertwined metal-organic-framework-based quasi-solid-state electrolyte for long-cycle-life dual-ion batteries

Abstract

Dual-ion batteries (DIBs) are promising for efficient energy storage, yet they encounter challenges in cycling stability due to solvent co-intercalation and electrolyte decomposition at high voltages during anion intercalation. Herein, we propose integrating metal-organic frameworks (MOFs) with intertwined zwitterionic polymers as a quasi-solid-state electrolyte (QSSE). This design exploits the synergistic effect of the mesoporous structure of MOFs and zwitterionic polymers synthesized within the pores, thereby enhancing ion transport kinetics and weakening solvent-ion interactions. The PVIPS@MIL-101 QSSE exhibits an improved ionic conductivity of 0.902 mS cm⁻¹ at 25°C and wide electrochemical stability up to ∼5.1 V vs. Li/Li⁺. Notably, the DIBs with PVIPS@MIL-101 QSSE demonstrate impressive high-rate capabilities and extended cycle life without additives, retaining 93.3% capacity after 4,000 cycles at 10 C, surpassing conventional battery systems.