Abstract
Citrated porous PVDF-co-HFP containing LiClO4–EC–DEC is prepared with a preferential polymer dissolution process using polyvinyl acetate to create a different porosity ratio of the optimized citrated membrane. All citrated samples (3,5,7,9,11 wt. %) are characterized using X-ray diffraction to show that the sample containing 7 wt. % citric acid has the lowest crystalline structure. The optimized sample is mixed with different PVA concentrations, (4, 8, 12, 16 wt. %), and then all PVA removal copolymer composite samples are immersed in a mixture of a liquid electrolyte containing LiClO4, EC, and DEC. The swelling and porosity measurements show that the sample containing 16 wt. % of PVA removal has the highest values, 68% porosity and 115% swelling. Scanning electron microscope is used to show the porous structure of the optimized citrated copolymer electrolyte sample (16 wt. % of PVA removal) compared to the before removing PVA one. DC-electrical conductivity measurement is performed to show the effect of porosity on the conduction process. The sample having 8 wt. % PVA removal shows a high conductivity value of 8 × 10−4 S cm−1 compared to the other samples at room temperature. Complex impedance, electrochemical stability and stress–strain curve are also studied. All results are collected and discussed.
Role of PVA removing in creating a porous membrane, and porosity dependence of conductivity. [Display omitted]
•Citrated porous gel copolymer composite electrolyte as a new electrolyte was prepared by a solution cast technique.•Films with optimized crystalline structure and porosity percent were obtained.•Good ionic conductivity at room temperature, 8 × 10−4 Ω−1 cm−1.•Good electrochemical stability, decomposition voltage = 4.2 V.