We present an enzymeless, surface mountable glucose fuel cell based on abiotic catalysts. The device is intended as an energy harvesting implantable power supply for low power medical implants and sensors. After 50 days of operation in physiological glucose solution the fuel cell exhibited a stable performance of 1.1 muW/cm2. The demonstrated lifetime of our glucose fuel cell therefore already exceeds the maximum lifetime reported for devices based on enzymatic catalysts. This renders the concept a promising approach for the development of autonomous and sustainable power supply systems for long- term medical implants.