Due to their different structures and virtually unlimited raw material source, organic materials could triumph over many inorganic compounds as electrodes. However, most organic materials suffer the weaknesses of poor electron conducting and being soluble in electrolytes, which leads to low capacities and short lifetimes of batteries. In order to address these weaknesses, we present a readily scale-up-able process to polymerize N-heterotriangulene triketone, resulting in an essentially insoluble, two-dimensional conjugated polymer PHTA, showing a layered morphology with an interlayer spacing of 3.53 Å. Benefiting from the polycyclic aromatic hydrocarbonic features, PHTA is insoluble in electrolytes and has high electrical conductivities (2.33 × 10−2 S cm−1). In LIBs, the PHTA electrode reveals a specific capacity of 380 mAh g−1 with an average attenuation rate of 0.026%. These results indicate PHTA to be a superior candidate and open a seminal future for N-heterotriangulene polymers for energy storage.