An electrically insulated conductor for carrying signals or current
includes a solid or stranded copper core of various geometries with only
a single electrically insulating and thermally conductive layer of
anodized aluminum (aluminum oxide). The device is made by forming a
uniform thickness thin sheet or foil of aluminum to envelop the copper or
copper alloy core. The aluminum has its outer surface partially anodized
either before or after forming to the core in an electrolytic process to
form a single layer of aluminum oxide.