Hypersaline Aqueous Lithium-Ion Slurry Flow Batteries

The rising demands on low-cost and grid-scale energy storage systems call for new battery techniques. Herein, we propose the design of an iconoclastic battery configuration by introducing solid Li-storage chemistry into aqueous redox flow batteries. By dispersing tiny-sized Li-storable active material particulates and conductive agents into high-salinity aqueous electrolytes, a slurry flow battery based on an intriguing interfacial charge “passing-down” mechanism is constructed, presenting expanded potential window, favorable redox stability, and good fluidity. A low-cost commercial dialysis membrane is used as the separator, which could efficiently inhibit the crossover of cathodic/anodic particulates via size exclusion and enable unimpeded transmembrane Li+ migration. The aqueous lithium-ion slurry flow batteries achieve nearly 100% Coulombic efficiency, long cycling life, high safety, and low system cost, holding great promise for large-scale energy storage applications.