【摘要】 以聚酰亚胺(PI)作为粘结剂,利用纳米二氧化硅(SiO2)颗粒对锂离子电池用聚丙烯(PP)隔膜进行陶瓷改性,得到PP/SiO2复合隔膜。通过场发射扫描电镜、热收缩、交流阻抗及充放电实验等方法,对复合隔膜的热性能及电化学性能进行分析。制备的复合隔膜具有良好的耐热收缩性能,纳米颗粒间形成了高度发达的孔隙结构,150℃时的热收缩率仅为1.8%,可提高锂离子电池的安全性。30 min涂层复合隔膜组装的LiCoO2/Li电池,以0.2 C充电、0.5 C放电,在2.75~4.20 V循环,首次放电比容量为140 mAh/g,高于PP隔膜组装电池的138 mAh/g。更多还原

【Abstract】 Nano silicon dioxide( SiO 2) particle was coated on polypropylene( PP) separator with polyimide( PI) as binder to get modified composite separator. The composite separator was characterized by SEM,thermal shrinkage,A. C. impendance and chargedischarge experiments. The thermal performance of ceramic modified composite separator was fine,the thermal shrinkage at 150 ℃ was only 1. 8% and the safety of Li-ion battery could be improved. Due to the highly developed porous structure formed by nanoparticle,when cycled in 2. 75 ~ 4. 20 V with 0. 2 C charging,0. 5 C discharging,the initial specific discharge capacity of LiCoO 2 / Li cell assembled with 30 nm coating composite separator was 140 mAh / g,higher than PP separator( 138 mAh / g).更多还原