This study reports the development of an entanglement association polymer electrolyte (PVFH-PVCA) for Li-metal batteries. The electrolyte, composed of a poly (vinylidene fluoride-co-hexafluoropropylene) (PVFH) matrix and a copolymer stabilizer (PVCA), is designed to improve the interface stability between Li-rich Mn-based oxide cathodes and electrolytes. The entangled structure of PVFH-PVCA imparts excellent mechanical properties, eliminates stress from dendrite growth, and forms a stable interface layer, enabling Li//Li symmetric cells to cycle steadily for over 4500 hours at 8 mA cm\(^{-2}\). PVCA acts as a stabilizer, promoting the formation of an electrochemically robust cathode-electrolyte interphase, delivering high specific capacity and excellent cycling stability with 84.7% capacity retention after 400 cycles. The PVFH-PVCA electrolyte also shows promising performance in full cells, achieving 125 cycles at 1 C (4.8 V cut-off) with a stable discharge capacity of ~2.5 mAh cm\(^{-2}\) for Li\(_{1.2}\)Mn\(_{0.56}\)Ni\(_{0.16}\)Co\(_{0.08}\)O\(_2\)/PVFH-PVCA/Li. The study highlights the potential of PVFH-PVCA as a high-performance polymer electrolyte for Li-metal batteries, addressing the challenges of dendrite growth and improving safety and energy density.This study reports the development of an entanglement association polymer electrolyte (PVFH-PVCA) for Li-metal batteries. The electrolyte, composed of a poly (vinylidene fluoride-co-hexafluoropropylene) (PVFH) matrix and a copolymer stabilizer (PVCA), is designed to improve the interface stability between Li-rich Mn-based oxide cathodes and electrolytes. The entangled structure of PVFH-PVCA imparts excellent mechanical properties, eliminates stress from dendrite growth, and forms a stable interface layer, enabling Li//Li symmetric cells to cycle steadily for over 4500 hours at 8 mA cm\(^{-2}\). PVCA acts as a stabilizer, promoting the formation of an electrochemically robust cathode-electrolyte interphase, delivering high specific capacity and excellent cycling stability with 84.7% capacity retention after 400 cycles. The PVFH-PVCA electrolyte also shows promising performance in full cells, achieving 125 cycles at 1 C (4.8 V cut-off) with a stable discharge capacity of ~2.5 mAh cm\(^{-2}\) for Li\(_{1.2}\)Mn\(_{0.56}\)Ni\(_{0.16}\)Co\(_{0.08}\)O\(_2\)/PVFH-PVCA/Li. The study highlights the potential of PVFH-PVCA as a high-performance polymer electrolyte for Li-metal batteries, addressing the challenges of dendrite growth and improving safety and energy density.