Multicomponent additive-mediated interfacial engineering enables highly stable lithium-ion pouch cells under harsh working conditions

The interfacial chemistry influenced by electrolyte components, including lithium salts, solvents, and additives, has attracted significant attention for its critical role in advancing high-performance lithium-ion batteries (LIBs). However, the instability of interfacial interactions between traditional electrolytes and electrodes presents a major obstacle to achieving optimal LIB performance, especially in conditions of high temperature and cut-off voltage. This work introduces an interfacial engineering method utilizing a combination of additives − specifically, fluoroethylene carbonate, ethylene sulfate, and propane sultone (referred to as FDP) − to enhance the conventional carbonate electrolyte for applications in high-voltage and high-temperature LIBs. These additives effectively adjust the interactions between lithium ions and solvents, reducing desolvation energy, thereby decreasing gas evolution, mitigating extensive solvent decomposition, and promoting the formation of a thin, uniform, low-impedance elastic interfacial film on both the anode and cathode. Noteworthy results include a 97.3 % capacity retention at 4.4 V over 250 cycles at 45 °C in a 1.7 Ah-level single crystal LiNi 0.6 Co 0.1 Mn 0.3 O 2 (SC-NCM 613 )||graphite pouch full cell incorporating FDP additives. This interfacial engineering approach facilitated by these multicomponent additives presents a highly promising and practical pathway for achieving long-lasting high-voltage and high-temperature LIBs.