A power cable having improved durability and associated methods of assembly and use are described herein. In one aspect, the power cable is adapted for use in powering an implantable circulatory pump system. The cable includes one or more conductors of uninsulated wire strands that are loosely packed so as to move relative one another during cable flexure. The driveline cable may include a plurality of conductors, each comprised of multiple uninsulated bundles of uninsulated, loosely packed wire strands of a conductive material, that are wrapped about a central core. The cable may include at least six conductors, each conductor having at least 200 wire strands of a 30 gauge or higher. The cable may include the plurality of wire strands wound in a Litz style configuration to provide improved durability over many cycles of use at reduced cost, improved integrity of the electrical connection and reduced diameter.