CAJ | 학술논문

通过静电纺丝和热亚胺化处理制备热固性聚酰亚胺（PI）纳米纤维膜，并研究隔膜的力学性能及在2种充电截止电压（常用的4.2 V和高电压4.4 V）下的电化学循环性能.结果表明：PI纳米纤维的平均直径为276 nm，作为隔膜的孔隙率高达92%，且其吸液率远远高于商业用Celgard2400隔膜；0.2C/0.2C速率50次充放电循环下，2种电压范围下的容量保持率均在80%以上，且在2.8～4.4 V高电压下的容量保持率高达91.6%，明显优于Celgard2400；在2种电压范围内，随着放电倍率的增大，其比容量衰减较Celgard2400隔膜缓慢，PI膜表现出更优异的倍率性能.
통과정전방사화열아알화처리제비열고성취선아알（PI）납미섬유막，병연구격막적역학성능급재2충충전절지전압（상용적4.2 V화고전압4.4 V）하적전화학순배성능.결과표명：PI납미섬유적평균직경위276 nm，작위격막적공극솔고체92%，차기흡액솔원원고우상업용Celgard2400격막；0.2C/0.2C속솔50차충방전순배하，2충전압범위하적용량보지솔균재80%이상，차재2.8～4.4 V고전압하적용량보지솔고체91.6%，명현우우Celgard2400；재2충전압범위내，수착방전배솔적증대，기비용량쇠감교Celgard2400격막완만，PI막표현출경우이적배솔성능.
The thermosetting polyimide (PI) nano-fibers based nonwoven membrane is prepared by electrospinning technique and followed by thermal imidization. The physical and mechanical properties of PI nano-fibers based nonwoven separators are tested and the electrochemical performance of the PI membrane for lithium ion battery at different charge cut-off voltage (herein, common voltage 4.2 V and higher 4.4 V) is investigated. The results show that the average diameter of PI nano-fibers is as fine as 276 nm; the porosity of PI nano-fibers based nonwoven separators is up to 92% and they exhibit better wettability for the polar electrolyte compared to the commercial Celgard 2400 membrane; After 50 cycles at 0.2C/0.2C charge and discharge rate, the capacity retention ratio of the cell assembled with PI nano-fibers based nonwoven separators at both voltage range is higher than 80%, especially that of 4.4 V charge is up to 91.6%, which are obviously superior to commercial Celgard 2400 membrane; moreover, the special capacity of PI separators fades slower than Celgard 2400 membrane with the increase of discharge rate at both situation.