A method for interconnecting a first flex printed circuit board (PCB) with a second flex PCB. The method includes: providing the first flex PCB with holes at contact locations to be electrically coupled to the second flex PCB; providing the second flex PCB with electrical pads corresponding to the holes at the contact locations; applying a non-conductive material between the first PCB and the and second PCB with clearances for each of the electrical pads; aligning the first PCB with the second PCB so that the holes in the first PCB are in line with the corresponding electrical pads on the second PCB; bonding a portion of flat areas on the first and second PCBs together; dispensing a conductive adhesive into the holes to fill the space created by the holes, corresponding clearances of the non-conductive material, and the corresponding electrical pads; and curing the conductive adhesive.