| Polymer electrolyte has extensive application promise in chemical power source, electrochromic materials, photoelectrochemistry, and chemical sensor, etc. Solid polymer electrolyte (SPE) is safety in performance and flexibility in the shape and does not contain any organic liquid, but the ionic conductivity is in the magnitude of 10-7～10-8 S·cm-1 at room temperature which is insufficient for practical application. Pure gel polymer electrolyte(GPE) has outstanding properties such as high energy density, long cycle life, low leakage, light weight and flexible shape. The ionic conductivity of GPE can reach the magnitude of 10"3 S·cm-1 at room temperature, "which can satisfy the practical request basically, but still lower than that of liquid electrolyte (10-2 S·cm-1). The low ionic conductivity will limit the discharge rate and low temperature performance of the battery system. Because of the existence of small molecule solvents, the electrochemical and thermal stability, mechanical property and electrode/electrolyte interface stability of polymer electrolyte are poor. The whole preparation process of pure gel polymer electrolyte need no moisture conduction which raising the cost of production.In order to solve these problems of pure gel polymer electrolyte, a conductive polymer poly(2,5-dihydroxyanine) (PDHA) is used to prepare polyvinylidene fluoride-poly(2,5-dihydroxyanine) (PVDF-PDHA) and polyvinylidene fluoride-polyethylene oxide-poly(2,5-dihydroxyanine) (PVDF-PEO-PDHA) porous polymer electrolyte membranes for the first time. Simple phase inversion method is used to prepare the polymer porous membranes, which avoid the request for no moisture conduction. The membrane morphology, thermal stability, electronic conductivity and etc are studied by Field emission scanning electron microscopy (FE-SEM), Thermal gravimetric analysis (TG), porosity, electrolyte uptake and volume resistance testing. Then these porous polymer membranes are gelify by being soaked in electrolyte, and the electrochemistry capability is studied by Linear Sweep Voltammetry (LSV) and Electrochemical Impedance Spectrum (EIS). The main results are as follows:When the solvent is N, N-Dimethylformamide (DMF) in contract of N-methyl pyrrolidone (NMP), two types of polymer porous membranes have better performances, such as porosity and electrolyte uptake, that lead to a higher ionic conductivity.EIS indicates that ionic conductivity of porous gel polymer electrolyte at room temperature is enhanced with the content of PDHA increased. The ionic conductivity of PVDF-PDHA porous gel polymer electrolyte is up to 4.2×10-3 S·cm-1 when the content of PDHA is 0.2 (wt% vs PVDF), and the ionic conductivity of PVDF-PEO-PDHA electrolyte is up to 1.5×10-2 S·cm-1 when the content of PDHA is 0.3 (wt% vs PVDF) respectively, which has reached the magnitude of liquid electrolyte (10-2S·cm-1).The increase of ionic conductivity at room temperature is independent of porosity and electrolyte uptake by the integration analysis of porosity, electrolyte uptake and ionic conductivity. Considering the special construction and solubility of PDHA, the relationship between ionic conductivity and content of PDHA is accord the Effective Medium Theory (EMT)FE-SEM photographs show that the polymer membranes are abundant in pore, and good link between the internal pore. This construction provides continuous channels to liquid electrolyte, which contributes to the ionic transfer. LSV shows that the electrochemical stability window of two types of electrolyte is 3.5V, it satisfy the request for organic electrolyte super capacitor, but is a weak point for Lithium ion battery. Two types of electrolytes all possess good thermal stability, the weight loss temperature is at 250℃for PVDF-PDHA polymer membranes and 230℃for PVDF-PEO-PDHA polymer membranes.
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