Separator with high ionic conductivity enables electrochemical capacitors to line-filter at high power.

ABSTRACT: Line-filtering electrochemical capacitors (LFECs) are demonstrating advantages in line filtering over traditional electrolytic capacitors. However, they can only function at no-load or low-power conditions due to the limited high-frequency capacitance resulting from the excessive ionic resistance, despite much progress in electrode materials. Here, we show separators dominate both ion migration and capacitance in LFECs. A 3 μm-thick thread-anchor structured separator is developed, featuring both accelerated ionic transport and reliability, leading to a low ionic resistance of 25 mΩ cm². With a phase angle of -80° at 120 Hz, the assembled device has an areal capacitance of 6.6 mF cm^-2. Furthermore, stack integration in parallel breaks the trade-off between capacitance

SUBMITTER: Hu Y 

PROVIDER: S-EPMC11926240 | biostudies-literature | 2025 Mar

REPOSITORIES: biostudies-literature