Functional Role of Aramid Coated Separator for Dendrite Suppression in Lithium-Ion Batteries

Abstract

The separator is an essential important key material in lithium-ion batteries (LIBs) because it is in contact with the positive and negative electrodes and the electrolyte. Aramid coated separators (ACS) are widely used in automotive and consumer batteries as high-performance separators for LIBs with high safety and excellent lifetime characteristics. Although much effort has been made to improve the electrolyte composition, the lithium deposition on the surface of the graphite electrode at low temperature and the high charge rate is still an unsolved problem in LIBs. In this work, lithium metal is used as a counter electrode, and a separator was placed between lithium metal and graphite composite electrode. The lithium was deposited on the surface of the graphite composite electrode through the separator. Then, the functional role of ACS in the initial deposition process was investigated. The dendrite blocking effect of ACS was studied by the observation of dendrite growth and pulse cycle performance.