Coating separators were prepared by coating both sides of porous polyethylene(PE) membranes with aluminum oxide (Al2O3). The morphology study showed that uniform coating layers were formed on the PE separa-tors. Compared with the PE separator,the thermal stability of the composite separators was improved greatly. Mean-while,a higher amount of electrolyte solution is expected to be retained by the composite separator. By using the Al2O3coated PE separator,lithium-ion cells were assembled and AC impedance spectroscopy was used to character-ize the impedance. The cycling performance of cells was evaluated,and were proven to be having better capacity re-tention than the cells prepared with polyolefin membrane.%以聚乙烯(PE)湿法膜为基体,在其两侧均匀涂覆氧化铝(Al2O3)颗粒,得到一种复合涂层PE锂离子电池隔膜.对复合隔膜的形貌、透气性、吸液率和热稳定性进行了研究,结果表明:Al2O3涂层均匀涂布于PE膜表面,在105℃下放置1h,复合PE膜没有出现较大的热收缩,同PE非涂覆膜相比具有优越的热稳定性能,可以有效提高锂离子电池的热安全性能.并且混合颗粒具有较高的比表面积,使得涂覆膜对电解液的吸液率高.以Al2O3复合PE膜做为隔膜组装电池并进行分析表明,隔膜的离子电导率升高,并且可以显著提高长期充放电循环时电池容量保持率.
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