A system includes a conversion circuit of a vehicle system that conductively couples a conversion device with first motors of the vehicle system. The electrical conversion device converts non-electrical energy into conversion-based electric current that is conducted to the first motors. The system also includes a storage circuit of the vehicle system that conductively couples a storage device with second motors of the vehicle system. The storage device supplies stored electric current to the second motors of the vehicle system. The system also includes a controller configured to control the second motors to brake and generate charging electric current that is conducted through the storage circuit to charge the storage device. The conversion circuit and the storage circuit are separate circuits such that the storage device is not charged with the conversion-based electric current conducted in the conversion circuit.