A resealed inkjet printer cartridge and method of manufacture in which an ink cartridge is reconditioned, recharged and resealed by a process which substantially eliminates “air lock” or interruption of ink flow to the printer head due to entrained air; which provides for welding together recharged cartridge subassemblies without the use of consumable adhesive or glue; and having a keyless cap adapted for use in various keyed cartridge receptacle inkjet printers.