Preparation And Study Of PAN/TPU/PS Gel Polymer Electrolytes For Lithium Ion Battery

Lithium ion battery based on gel polymer electrolyte(GPE)is the new generation of rechargeable system developed from liquid lithium ion battery.It possesses high energy density,long cycle life,negligible leakage,light weight and flexible shape.The polymer electrolyte lithium battery is attractive a lot of researchers’ attention.In order to improve the ionic conductivity of the GPE and the compatibility of the GPE with electrode,a ternary PAN/TPU/PS base GPE was prepared by electrospinning in the lithium ion battery.The whole experimental work was studied on three aspects.Firstly,the blend films of PAN/TPU,PAN/PS,TPU/PS and PAN/TPU/PS were prepared by electrospinning.After drying,put all films into 1 mol/L LiPF6-EC/DMC electrolyte to prepare our desired GPE.The results show that the ionic conductivity of PAN/TPU/PS-based GPE is much better than that of the other three,reaching 3.83 ×10-3 S cm-1.And the electrochemical stability window was 5.8 V,which was much wider than that of the other three.At 0.1C magnification,the first charge and discharge capacity of the battery is 161.70 mAh g-1and 161.44 mAh g-1;at 1.0C magnification,the higher discharge capacity of 150.07 mAh g-1 is shown;Mechanical properties are good which the elongation at break is as high as 115.15% and the tensile strength is 9.86 MPa.The use of the ternary GPE lithium-ion battery cycle performance,high temperature performance and magnification charge and discharge performance are significantly improved.Secondly,a series of PAN/TPU/PS electrospinning films were prepared by electrostatic spinning.They were dried and placed in 1 mol/L LiPF6-EC/DMC electrolyte to obtain GPE with different mass ratio.The ion conductivity of PAN/TPU/PS of sample PTP5 was 3.83 × 10-3S cm-1.At the 0.1C magnification,the initial charge/discharge capacity of the PTP5 GPE is 161.70 mAh g-1 and 161.44 mAh g-1;After 50 cycles of the test,the discharge capacity is still as high as 150.85 mAh g-1,the stability is very good.In combination,PTP5 GPE is more suitable for use in lithium-ion batteries.Finally,electrospinning films were prepared by electrospinning a series ofdifferent concentrations of PAN/TPU/PS solution.and then dried into 1 mol/L LiPF6-EC/DMC to obtain GPE.The electron absorption rate of the electrospinning film prepared by 11% concentration of PAN/TPU/PS solution was 347%;and the ionic conductivity at this concentration was 4.01 × 10-3 S cm-1.At 0.1C,the initial charge and discharge capacity of the cells prepared by 11% concentration PAN/TPU/PS was 165.55 mAh g-1 and 165.47 m Ah g-1.After 50 cycles,The discharge capacity is still as high as 157.62 mAh g-1,the stability is very good,The capacity attenuation is relatively small,while other concentrations in the capacity of the performance of the attenuation on the poor.PAN/TPU/PS-based GPE film prepared by 11% concentration were excellent in physical and electrochemical performance,and was the best choice for lithium ion battery separator materials.