A novel polymeric lithium tartaric acid borate (PLTB) was synthesized via an one-step reaction in aqueous solution. The polymer electrolyte of PLTB@PVDF-HFP (poly(vinylidene fluoride-co-hexafluoropropene)) was developed by a doctor-blading followed by a soaking process in propylene carbonate (PC). It was manifested that the PC swollen PLTB@PVDF-HFP exhibited excellent electrochemical stability and compatibility with lithium metal electrode, high ionic conductivity and high lithium ion transference number at an operating temperature of 80°C. The cells using the PC swollen PLTB@PVDF-HFP as electrolyte showed stable charge/discharge profiles, preferable rate capability and satisfactory cycling performance at high temperature. These superior performances of PC swollen PLTB@PVDF-HFP could endow this class of polymer electrolyte a very promising application in lithium batteries operating at relatively high temperature.