Easy-refill ink cartridges (including inkjet cartridges) modify the inside of the ink cartridge, take out the sponge inside the ink cartridge, expand the internal capacity of the ink cartridge, so as to achieve the purpose of increasing the printing volume of the ink cartridge, and then use professional design (already The ink cartridge lid balancing air pressure device (obtained a national patent) replaces the original ink cartridge lid to achieve stable air pressure and ensure that the ink cartridge can print smoothly.