Self‐generated Conjugate Magnetic Field Realizing High Voltage and Fast Lithium‐ion Transport of Polyether Electrolytes for Lithium Metal Batteries

Abstract The in situ formed poly(1,3‐dioxolane) (PDOL) electrolyte has garnered significant attention due to its simple processing and excellent interface compatibility, yet the practical application of in situ PDOL electrolytes still suffers from the issues of poor high‐voltage stability and low ionic conductivity. Herein, Self‐Generated Conjugate Magnetic Field (SGCMF) as a novel strategy is proposed to solve these problems and first reveal the correlative mechanisms between the internal magnetic field and polyether‐based electrolytes. Specifically, SGCMF is induced by the initiator Trityl tetrakis(pentafluorophenyl)borate (TMTPB), which accelerates the transport of Li + in the polymer electrolyte through the Lorentz force. Meanwhile, the SGCMF can alleviate the localized electron density of PDOL, thereby significantly increasing the intrinsic antioxidant activity of PDOL chain. As a result, this multi‐level strategy leads to a high ionic conductivity of 0.91 mS cm −1 (30 °C) and the electrochemical stability window up to 4.8 V. Furthermore, the assembled LiNi 0.6 Co 0.2 Mn 0.2 O 2 ||PDOL‐TMTPB||Li cells exhibit an impressive capacity retention rate of 86.1% after 250 cycles at 4.5 V (1C). This study not only overwhelmingly realizes the in situ polymerized high‐voltage PDOL electrolyte but also uncovers the immense potential of self‐generated conjugate magnetic fields in SPE‐based batteries.