Electronic – DIY kinetic energy harvester

I saw this answer and glanced at my watch, it just so happens to function in the way you describe. There's a large half-disc pendulum inside which presumably is used to collect the kinetic energy. It can run for about let's say one day If I walk about 2-4 miles a day. If I move throughout, indefinitely, but then, watches require very little power to begin with.

Energy Storage How much energy you can store only depends on your capacitors and batteries, etc, it's not inherent to the the energy generation method you want to use.

Other Devices I don't see why you would look at it this way as mentioned before. Decide on what you want to use kinetic energy to power and then do a few basic calculations based solely on first principles, assuming 100% efficiency of kinetic energy -> chemical / electrical energy and you'll quickly see what's doable and what's not. As a general guide, microWatts, up to a maximum of say a few milliWatt is probably all you can do (this very much depends on the type of physical activity you're using, more strenuous activites could very much reach into Watts)

Schematics I can't give you one, but I can tell you the design is very simple. Take the pendulum in my watch mentioned earlier(here's a picture of one from your article):

While I can't specify exactly how thing's work internally, what I do know is this:

"Electromagnetic induction is the production of an electric current across a conductor moving through a magnetic field"

After reading the provided article, the pendulum is used to spin a pinion(visible in the picture) - just a small gear, which in turn drives an electric generator(which has been documented plenty). Anyway, you're likely to get an AC voltage from the electric generator. You can use perhaps a bridge rectifier, maybe a voltage regulator as well and store this in the energy storage device of your choice.

Finally Like I said before, decide on what you want to power first, that's the only way you're going to be able to do this properly. Make an upper maximum required power for the circuit you want to power and proceed from there. Feel free to ask for any more help but based on the information so far, this is all I can do.

Zero unless the phone is transmitting, which it isn't most of the time. Note that the circuit in the link you posted only works 1. shortly after the phone is turned on, 2. while talking on a call, 3. while sending a text. So for any given 5 second period, your harvester is almost certainly not going to get any energy from the phone at all. Now, when your phone is transmitting data to a cell tower (perhaps you are using it to talk to someone) then the transmit power will depend on the distance to the nearest cell tower. The transmitters in phones are actually rather powerful, I think some are even capable of transmitting at a watt, though the battery drain when transmitting at that high of a power level is significant. My guess is that if you get lucky and the phone is transmitting at high power, you could extract a few tens of mW. More likely you would only get a few uW, especially if the phone is connected to a local wi-fi network instead of to the cell network. However, most of the time you're going to get nothing.