How much energy can we draw from miniature implanted device that collects energy from human body?
The goal is to design a type of implanted device in human body used to communicate over a distance, hence a reliable power supply is required. I am thinking about a combination of super-capacitor (examples: this) charged over human body to make this device self-powered. A possible energy source might be glucose.
Transmission over a long distance certainly requires a nontrivial amount of power, and being an implanted device makes this trickier. Currently there are nanoradios and this kind of design but the transmission range are not enough for long-range (say, over 100m or even over 1 mile) communications.
Now there are designs of bio-batteries, see for example this and this. But if the biochemicals, say glucose, are to be collected from human body, how much energy can a setup, implanted and “coupled” with human body generate and stored reliably? Also note that the device shouldn’t be too large: the size should be millimetres in scale.
I want the design to be scientific and based on current technology as much as possible. Hence I wonder if this is realistic, and if not, what are the current developments and potential difficulties to overcome?