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.