Separators for Lithium‐Ion Batteries: A Review on the Production Processes and Recent Developments

Abstract Recently, much effort has been devoted to the development of battery separators for lithium‐ion batteries for high‐power, high‐energy applications ranging from portable electronics to large‐scale energy storage for power grids. The separator plays a key role in battery construction because it functions as the physical barrier to prevent electronic contact between the two electrodes and at the same time serves as an electrolyte reservoir, facilitating the ionic conduction. The purpose of this Review is to describe the requirements and properties of membrane separators for lithium‐ion batteries, the recent progress on the different types of separators developed, and the manufacturing methods used for their production. Specifically the large‐scale manufacturing processes are highlighted along with the processing parameters that affect their properties. The outlook and future directions regarding the development of advanced separator technologies are also discussed.