Disclosed is a medical power system for powering an implantable medical device including an implantable rechargeable battery pack, a wearable power source, a power cart, and an external power supply. The system may be used in three modes: 1) Fully disconnected (powered by implanted battery only); 2) Power provided by a wearable power source and/or a portable wheeled power cart via an inductive link, and 3) Nonportable power provided by a non-portable source such as an AC outlet with an uninterruptible power supply. The system includes automatic choice of the optimum source of power depending on the circumstances, and greatly increases “untethered time” a bionic-dependent patient may spend.