The pursuit of extended driving ranges of electric vehicles has spurred the use of nickel-rich layered cathodes, yet raised safety concerns. Existing ethylene carbonate-free electrolytes improve safety but compromise electrochemical performances due to the delicate balance between anode interphases. We introduce a novel electrolyte composed of propylene carbonate (PC) and triple lithium salts, which synergistically reinforces both cathode and anode interfaces. PC's low kinetic reactivity with LiNi0.8Mn0.1Co0.1O2 (NCM811) at the cathode minimizes heat generation and oxygen evolution. To stabilize the anode, bis(fluorosulfonyl)imide (FSI-) anions are integrated to construct an anion-driven interface, while difluoro(oxalato)borate (DFOB-) is added to lower PC's de-solvation energy and prevent co-intercalation. NCM811/Graphite pouch cells utilizing this electrolyte show enhanced safety, cyclability, and rate capability, surviving 60 min at 180℃ without incident. Post-mortem analysis reveals suppressed parasitic reactions and the formation of a robust solid electrolyte interphase (SEI). This research offers a critical framework for the design of electrolytes tailored for high-energy lithium-ion batteries.
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