Preparation And Characterisation Of Porous Solid Polymer Electrolyte

Gel polymer lithium batteries (GPLB) not only have the excellent performance of liquid lithium battery, but also can resolve the possible problems of leakage and blast owing to no free liquid electrolyte in GPLB. It is also very convenient to design the shape at will. Now the ionic conductivity of gel solid polymer electrolyte (GSPE) can reach the magnitude of 10-3 S·cm-1, which can satisfy the practical request. However, it is still lower than that of liquid electrolyte (10-2 S·cm-1), which causes the fall of high rate discharge and low temperature performance of lithium battery. The cost of the process is very high and it is difficult to treat with the disused solvents, therefore, it is difficult for most liquid lithium battery manufactures to transfer to produce GPLB.Focusing on the preparation process of lithium battery and GSPE membrane, by optimizing the component, the paper intends to resolve some of the key problems mentioned above and to prepare a PSPE with good performance by a simple phase inversion method. In this paper, three new sorts of GSPE membrane were synthesized,. We can get GSPE after the membranes were immersed in lithium electrolyte. For these synthesized PSPE, we studied their microscope morphology, thermal stability and ionic conductivity.1. A novel PSPE based on poly(vinylidene fluoride) and poly(ethylene oxide) blends was prepared by a simple phase inversion method, in which the addition of PEO can obviously improve the pore configuration and hence, the room temperature ionic conductivity was greatly enhanced. The heat performance and characterization of PSPE membrane were conformed by TG, SEM. The highest porosity of PSPE membrane is about 90% and ionic conductivity of PSPE is about 3.10×10-3 S·cm-1, and it is electrochemically stable up to about 5.5V(DMF is solvent);. Ionic conductivity of PSPE is about 6.10×10-4S·cm-1(NMP is solvent).2. In this paper doped and undoped polyaniline (PANI(ES) and PANI(EB))were synthesized using chemical method. Then two novel PSPE based on PVDF-PANI(ES) and PVDF-PANI(EB) were prepared by a simple phase inversion method. The heat performance and characterization of PSPE membrane were conformed by TG, Three-dimensional microscope. Comparing performance and characterization of PVDF-PANI(EB) with that of PVDF-PANI(ES),we found that PANI(ES) can form special conducting pathway in PVDF-PANI(ES) blends when its content is high enough, which can improve the ionic conductivity. The highest ionic conductivity of PSPE membrane is about 7.87×10-4 S·cm-1, and it is electrochemically stable up to about 3.5V.3. Focusing on PANI(ES) can form special conducting pathway in PSPE, we get a new mixed conductor of ion-electron (PVDF-PEO-PANI(ES))by phase inversion method. In the phase inversion process, NMP is the solvent. The heat performance and characterization of PSPE membrane were conformed by TGA, Three-dimensional microscope. The heat performance and characterization of PSPE membrane were conformed by TG, Three-dimensional microscope. The highest porosity of PSPE membrane is about 90%.The ionic conductivity of the mixed conductor was test. Its value is as high as 2.82×10-3 S·cm-1 at room temperature, and it is electrochemically stable up to about 4.5V.