Decoupling Electrolytes Enable 5 Ah Fast‐Charging Lithium‐Ion Pouch Cells

ABSTRACT Fast‐charging lithium (Li)‐ion batteries (LIBs) require electrolytes enabling rapid ion transport and desolvation. Conventional solvents strongly coordinate with lithium ions (Li + ), leading to high desolvation energy barriers and organic‐rich interphases limiting rate capability. Here, we propose a descriptor‐guided strategy for designing decoupling electrolytes to overcome sluggish Li + desolvation and poor interphase transport kinetics, enabling fast‐charging LIBs. A solvent screening descriptor (decoupling coefficient (D c )) is introduced based on the ratio of molecular volume to Li + affinity, which captures solvent electronic and steric effects. Among evaluated solvents, propyl acetate (PA), possessing a high D c , is identified as a suitable solvent to formulate decoupling electrolytes, which lowers the desolvation energy barrier, promotes anion participation, and fosters an inorganic‐rich solid electrolyte interphase (SEI). Consequently, the PA‐based decoupling electrolytes enable exceptional fast‐charging LIBs. Li||graphite (Gr) cells deliver a capacity of 190.1 mA h g −1 at 6 C with 80% capacity retention after 2000 cycles. Furthermore, industrial‐scale 5‐Ah Gr||LiFePO 4 pouch cells, with a high cathode mass loading of 34 mg cm −2 , achieve an initial capacity of 4.29 Ah and retain 70% capacity over 600 cycles at 2 C. Even at 4 C, an impressive capacity of 4 Ah (138.9 Wh kg −1 ) can also be achieved.