<p>Organic cathode materials hold great promise for rechargeable batteries due to their high theoretical capacity, sustainable resources, and low carbon footprint, yet suffer from low conductivity and high solubility in liquid electrolytes, which result in inferior kinetics and poor cycling stability. Herein, we rationally design and synthesize a new conjugated carbonyl polymer (PTO-AQ) cathode with a unique donor-acceptor structure. The polymerization can effectively eliminate the dissolution of organic molecules, while the interlaced donor and acceptor units can endow the PTO-AQ polymer to serve as both donors and acceptors of electrons, thereby enhancing the electrical conductivity. Consequently, the PTO-AQ cathode exhibits high capacity, remarkable cycling stability, and high-rate performance in both Li and Na batteries. Notably, when paired with a Na-metal or hard carbon anode, the resulting Na batteries can stably operate for over 10,000 cycles with an extremely low-capacity decay rate (&lt;0.5% per 100 cycles) and retain a high capacity of 66 mAh g⁻¹ at an ultra-high current density of 40 A g⁻¹, representing a significant advancement in promoting organic batteries with long-cycling and ultra-fast charging.</p>