NFC chips are so cool, they are just a circuit board with no battery, no ongoing power, and just a little antenna  

They only 'power up' from the electromagnetic field emitted from your phone (the NFC reader) for the moment of time you want to interact with it by tapping it

Also check out “For our kinetic switches we use energy from motion as power source and to send a radio signal. This enables switches that are 100 % battery-free and maintenance-free.”

listener • reasoner • first principles maxi • COO @ delv.tech

Also check out “For our kinetic switches we use energy from motion as power source and to send a radio signal. This enables switches that are 100 % battery-free and maintenance-free.” https://www.enocean.com/en/products/kinetic-switches/