A brush apparatus for a slip ring system of a current-energized electric machine for a motor vehicle is provided for supplying a rotor of the electric machine with current, wherein the brush apparatus is securable to a component of the electric machine that is mounted in fixed relation to the rotor. The brush apparatus includes a brush carrier having a cartridge-type holder and a brush arranged in the cartridge-type holder and forming a sliding contact with a slip ring of the slip ring system. The brush apparatus also includes a retaining device, formed from an electrically insulating material for retaining the brush carrier, which has a securing region for securing the brush apparatus on the component, and a heat-conducting core enclosed in the retaining device, which is exposed for the purpose of heat dissipation at least in the securing region of the retaining device that is couplable to the component.