Coaxial Electro-Spraying/Electrospinning and Its Application in Modification of the Li-Ion Battery Composite Separator
A technology named coaxial electro-spraying/electrospinning for preparing composite membranes was introduced.First,the coaxial electro-spraying/electrospinning equipment was assembled,which includes an outer nozzle and an inner nozzle.Then the method was studied for the preparation of fiber/particle composite membranes.Polyvinylidene fluoride(PVDF)/SiO2 in DMF was utilized to prepare the particles from the outer nozzle of the equipment,and PVDF dissolved in a mixture of DMF and acetone was used to prepare the fibers from the inner nozzle of the equipment.The PVDF&PVDF/SiO2 composite membranes including particles and fibers were successfully prepared at the same time by the equipment.The analytical results show that the average fiber diameter is 0.43 μm,and the average particle size is 2.01 μm.Then the modified composite materials were in situ loaded on ultra-high molecular weight polyethylene(UHMWPE)to prepare a new Li-ion battery separator.According to the analytical data,the porosity of the composite separator is 85.96%,which is significantly higher than the 37.85%of the UHMWPE separator.The longitudinal shrinkage decreases from 7.28%to 5.26%,respectively.The compound separator contact angle reduces from 48.55° to 14.93°.The initial charge-discharge specific capacity of the experimental separator is increased from 107.8 mAh/g to 122.4 mAh/g compared to the unmodified separator.After 50 cycles,it still exhibits a good cycling stability.
NETL
NSTL
万方数据
维普
