Abstract: A wound capacitor having high current carrying capacity in which a capacitor winding is wrapped around a core assembly having high thermal conductivity. The core assembly transfers thermal energy from the interior of the capacitor to the exterior. The ends of the core assembly extend outwardly beyond the terminals for radiating heat to the exterior of the capacitor thereby increasing the current carrying capacity of the capacitor. The core assembly includes separated metal portions secured to an electrically nonconductive portion. Cover seals may be positioned over the ends of the core assembly in contact with the terminals. The capacitor may be hermetically sealed. The metal portions and the electrically nonconductive portion may be hollow tubes forming a passageway through the entire length through the core assembly.