A facile and environmental-friendly method is developed to enhance the mechanical properties and electrochemical performance of a carbonized melamine sponge (CMS) via commercial pen ink coating. The resultant binder-free CMS@ink foam displays an improved electrochemical performance as the freestanding electrode (301 mF/cm(2) at 5 mV/s). The areal capacitance retention was maintained at 96.2 and 92.5% when the electrode was bent to 90 and 180 degrees, respectively. Even after being bent at 90 degrees for 500 times, the capacitance retention can be as high as 92.2%. Our study shows that the ink-coating carbon would boost the electrochemical performance of CMS while maintaining its free-standing nature and high flexibility, making the CMS@ink foam a promising material for portable and wearable energy-storage devices.