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Gel polymer lithium -ion battery not only has excellent performance liquid lithium -ion battery , and because there is no free electrolyte in the battery liquid lithium -ion battery leakage , explosion and other issues that may arise , not only to improve the exterior design is also more flexible convenient, no metal shell packaging . Room temperature ionic conductivity of the gel polymer electrolyte (GPE) up to 10 -3 < / sup> S / cm magnitude , has been able to basically meet the requirements of the application , but compared to the conductivity of the liquid electrolyte ( 10 -2 < / sup > S / cm ) the GPE conductivity is still low , making gel polymer lithium -ion battery charge and discharge rate and low temperature performance are greatly reduced. And GPE whole preparation process the demanding moisture , resulting in a large investment in equipment , high cost , waste solvent handling difficult , is not conducive to the majority of the transformation of liquid lithium-ion battery manufacturers production gel polymer lithium ion battery . This thesis is precisely these problems exist from the gel polymer lithium ion battery , proceed from the lithium-ion battery and a gel electrolyte membrane preparation process , the preparation process of the porous gel polymer electrolyte , and the GPE group parts has been improved and optimized, a good performance of the porous gel polymer lithium ion battery was prepared . First, using a radical solution polymerization synthesis of a series of different monomer ratio of acrylonitrile and a copolymer of hydroxyethyl acrylate , to overcome polyacrylonitrile low inherent mechanical strength , mechanical stability is poor , weakness , and by using Fourier its composition characterized by Fourier transform infrared spectroscopy (FTIR) . Secondly, the use of phase transformation to the prepared porous gel polymer membrane , and to optimize the preparation process , by thermal analysis ( TGA ) , scanning electron microscopy (SEM) to characterize the performance and structure of the porous film of heat . Finally, the porous membrane was immersed in a liquid electrolyte , and to obtain a porous gel polymer electrolyte membrane , to obtain a battery material having intellectual property and high overall performance . By electrochemical workstation characterize the electrochemical performance . The room temperature ionic conductivity of the GPE up 4.08mS/cm; electrochemical window up to 5.5V, electrochemical stability window above the electrolyte must meet the requirements ( 0 to 4.5V vs. Li / Li < / sup>).
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