Research progress of separator materials for lithium ion batteries

In recent years, lithium-ion battery technology has developed rapidly. As one of the core materials in the battery, the separator determines the performance of lithium-ion battery, because its characteristics influence on the influence rate, cycle and safe performance for batteries. Therefore, we need further research in the fields of separator material and preparation technology. At the present, polyolefin separator is still the main production of the commercial lithium-ion battery separator, but the preparation process is transferring from dry process to wet process. In the field of research, different material systems have been developed, such as PET, PVDF, PMIA and so on. Firstly, the production technology of polyolefin separator briefly introduced. Then the results of nonwoven separator material, coating material research, and new separator preparation technology are mainly reviewed. Finally, the outlooks and future directions in this research field are given.