Frictional wear during sliding electrical contact is of increasing concern. In this study, a current-carrying friction-reducing coating was designed for an aluminum armature. The coating was a Sn-graphene (Sn-GE) composite prepared on an aluminum alloy by an electrobrush plating method. When the designed coating had low roughness, it displayed outstanding current-carrying friction properties and could effectively relieve arc erosion from the current-carrying friction. The Sn-GE composite coating reduced the friction coefficient compared to the aluminum substrate under 1 A conditions, and graphene transformed into amorphous graphite under the current-carrying friction, preventing direct contact between frictional couples. As the current rose to 5 A, no arc erosion was found in surface scratches.