Synthetic Polymer Separators for Next‐Generation Supercapacitors: Recent Progress and Future Direction

ABSTRACT Supercapacitors (SCs) have attracted much attention due to their capacity to charge and discharge quickly, generate high specific power, and have excellent cycling stability and electrochemical performance. The separator is an essential component of SCs since it helps prevent internal short circuits while improving the device's durability, cost‐efficiency, ionic conductivity, dependability, and thermal stability. However, standard commercial separators suffer several problems, including low heat resistance, high self‐discharge rates, low mechanical strength, and lower energy and power densities. To overcome these constraints, this review paper will examine the most recent advancements in separator materials, structural designs, and fabrication techniques in depth. In addition to evaluating existing work on the subject, it investigates creative approaches to improve separator stability and efficiency. This article discusses synthetic polymers, such as polyvinylidene fluoride, polypropylene, polyacrylonitrile, and poly(vinyl alcohol). These polymers make high‐performance separators with more power and energy output, a longer cycle life, and better capacitance retention. The paper also delves into the critical properties of optimal separators, emphasizing how these characteristics influence the electrochemical behavior and overall reliability of SCs.