A Review on Lithium-Ion Battery Separators towards Enhanced Safety Performances and Modelling Approaches

Abstract

In recent years, the applications of lithium-ion batteries have emerged promptly owing to its widespread use in portable electronics and electric vehicles. Nevertheless, the safety of the battery systems has always been a global concern for the end-users. The separator is an indispensable part of lithium-ion batteries since it functions as a physical barrier for the electrode as well as an electrolyte reservoir for ionic transport. The properties of separators have direct influences on the performance of lithium-ion batteries, therefore the separators play an important role in the battery safety issue. With the rapid developments of applied materials, there have been extensive efforts to utilize these new materials as battery separators with enhanced electrical, fire, and explosion prevention performances. In this review, we aim to deliver an overview of recent advancements in numerical models on battery separators. Moreover, we summarize the physical properties of separators and benchmark selective key performance indicators. A broad picture of recent simulation studies on separators is given and a brief outlook for the future directions is also proposed.

Advanced separators for lithium-ion batteries

“…[39] It is not just that scientists are discovering new materials for separators, they are also building mathematical and physical models to carry on the analytical work towards separators to find better materials theoretically. [40] As the technique of LIB matures, separators with higher performances are required. The current separators are still facing many problems.…”

“…Nonetheless, it is almost impossible to achieve all these properties simultaneously, so it is essential to balance them and focus on several properties according to different lithium-ion batteries. [40] In general, there is still much work to be done to generate better separators for the safety and better performance of lithium-ion batteries.…”

A Comparative Review of Lead-Acid, Lithium-Ion and Ultra-Capacitor Technologies and Their Degradation Mechanisms

“…Dimensional stability is related to the assembly process of the ESD [142]. When the battery is assembled, the electrolyte is dripped onto the separator-the absorption can cause shrinkage or curling which leads to wrinkles [149]. Wrinkles lead to uneven distribution of electrolyte and current which increases growth formations and decreases service life.…”

Advanced materials supply considerations for electric vehicle applications

“…The material is typically a synthesized plastic type of material, with various types such as polyethylene, polypropylene, polyolefin, and poly(vinylidene fluoride) being used and investigated as separator materials. 11 Further in the future, a new class of lithium battery being developed that is known as solid-state. It employs a solid rather than gel type electrolyte, with potential benefits for safety, temperature tolerance, and energy/power density, as well as possible use of metal rather than graphite anode materials.…”