Novel electrically conductive polymer composite structures having a horizontal plane that contain effective amounts of two different types of conductive graphitic nanofibers. The first type of graphitic nanofiber is aligned substantially parallel to the horizontal plane of the polymer structure and are comprised of graphite platelets that are aligned substantially parallel to the longitudinal axis of the nanofiber. The second type of conductive graphite nanofiber are aligned at an angle to the horizontal plane of the polymer structure and are comprised of graphite platelets aligned at an angle to the longitudinal axis of the nanofiber. The conductive polymer composite structures are further comprised of one or more polymer layers.