A locally solvent-tethered polymer electrolyte for long-life lithium metal batteries is introduced, which addresses the issue of DMF degradation in solid-state batteries. The electrolyte is designed with a Hofmann-DMF coordination complex to create a DMF-rich interface that enhances Li⁺ conduction through a ligand-assisted transport mechanism. This composite electrolyte achieves a high ionic conductivity of 6.5 × 10⁻⁴ S cm⁻¹ at room temperature and demonstrates stable cycling for over 6000 hours at 0.1 mA cm⁻² in Li || Li symmetric cells. When paired with sulfurized polyacrylonitrile cathodes, the full cell exhibits a prolonged cycle life of 1000 cycles at 1 C. The electrolyte also shows improved electrochemical stability and ionic conductivity, with a high Li⁺ transference number of 0.71. The design of the electrolyte, based on a dual-functional Ni-DMF additive, effectively prevents DMF migration and degradation, leading to a stable inorganic-rich SEI and durable electrolyte. The electrolyte exhibits excellent performance at both room temperature and low temperatures, with a high ionic conductivity even at -10°C. The study demonstrates the potential of this electrolyte for practical solid-state lithium-sulfur batteries.A locally solvent-tethered polymer electrolyte for long-life lithium metal batteries is introduced, which addresses the issue of DMF degradation in solid-state batteries. The electrolyte is designed with a Hofmann-DMF coordination complex to create a DMF-rich interface that enhances Li⁺ conduction through a ligand-assisted transport mechanism. This composite electrolyte achieves a high ionic conductivity of 6.5 × 10⁻⁴ S cm⁻¹ at room temperature and demonstrates stable cycling for over 6000 hours at 0.1 mA cm⁻² in Li || Li symmetric cells. When paired with sulfurized polyacrylonitrile cathodes, the full cell exhibits a prolonged cycle life of 1000 cycles at 1 C. The electrolyte also shows improved electrochemical stability and ionic conductivity, with a high Li⁺ transference number of 0.71. The design of the electrolyte, based on a dual-functional Ni-DMF additive, effectively prevents DMF migration and degradation, leading to a stable inorganic-rich SEI and durable electrolyte. The electrolyte exhibits excellent performance at both room temperature and low temperatures, with a high ionic conductivity even at -10°C. The study demonstrates the potential of this electrolyte for practical solid-state lithium-sulfur batteries.