Cellulose acetate synergized with HKUST-1 enhance lithium ionic conductivity and dendrite resistance of quasi-solid-state electrolytes for lithium metal batteries

Solid-state lithium metal batteries are considered as the next generation of high-energy-density batteries. However, the internal inorganic solid-state electrolyte in them suffers from issues such as low ionic conductivity, poor interfacial properties, and high production cost, which seriously hampers its commercialization. In this study, a copper-based metal-organic framework material (HKUST-1) is introduced with cellulose acetate as the polymer substrate. HKUST-1 possesses a controllable porous structure. Moreover, the unsaturated Cu 2+ within it disrupts the dense macro-hydrogen bonding inside cellulose, thereby giving rise to a cellulose acetate/LiTFSI/HKUST-1 quasi-solid-state electrolyte (CLH-X QSE) with multiple ion-transport channels. It exhibits high ionic conductivity (1.75 × 10 −3  S cm −1 ) at 30 °C. Additionally, it has excellent interfacial stability and can be stably cycled at room temperature for more than 2000 h. Meanwhile, the capacity retention of the LiFePO 4 /CLH-10-LiPF 6 /Li battery can still reach 97.29 % after 200 cycles at a current density of 0.2 C. This high-performance and inexpensive quasi-solid electrolyte furnishes inspiration for the development of next-generation energy storage devices and is anticipated to drive technological advancements and industrial upgrades throughout the battery industry.