I am doing a report about wireless TPMS, and I heard about products where the sensors in the valves do not need batteries at all (operate and transmit the data). Is that correct?? have you encountered one? there are all sort of energy harvesters mechanisms that generates power from vibrations or pressure that can probably do the work (piezo-electric, electromagnetic, active RFID, etc.).
I am trying to understand whether TPMS are becoming battery-less, and if so, with which mechanism?