High-Performance Aramid Paper-Based Separator for Supercapacitors

The separators of supercapacitors suffer from drawbacks such as poor mechanical properties, limited ion transport, and low thermal stability, which have impeded the advancement of supercapacitors. In this study, high-performance paper-based separators are developed using aramid as the raw material through a wet papermaking process. The separators demonstrate exceptional comprehensive performance, including good mechanical strength (11.57 MPa), remarkable porosity (81.9%), and outstanding thermal stability (exceeding 300 °C). Evaluation of the supercapacitors with aramid separators (AS separators) reveals that as the porosity decreases, the specific capacitance of the supercapacitor exhibits a declining trend under the same scan rate or current density. Notably, the supercapacitor with the grammage 9 g m–2 AS separator achieves a specific capacitance of up to 26.79 F g–1, surpassing the supercapacitor with the commercial separator under identical conditions (26.41 F g–1). After 1500 cycles at a current density of 1 A g–1, the specific capacitance retention rate of the supercapacitor with aramid separators remains above 90%, comparable to that of the supercapacitor with the commercial separator. These findings underscore the highly promising nature of the high-performance commercial paper-based separator material for supercapacitors prepared in this study, offering exceptional performance and safety.