Electropolymerized organic N/P bipolar cathode toward high energy and high power density sodium dual-ion batteries

PTPA-AQ, an in situ electropolymerized bipolar organic cathode for sodium dual-ion batteries, achieving 426 Wh kg −1 energy density after 300 cycles at 0.2 A g − ¹, with 3000 cycle stability at 5 A g − ¹ and 14.9 kW kg − ¹ power density.