Concrete chloride ion sensor

The utility model discloses a concrete chloride ion sensor which comprises a detection mechanism, an energy supply mechanism and a controller, the controller is respectively connected with the detection mechanism and the energy supply mechanism, the energy supply mechanism comprises a metal sheet and an energy storage capacitor, the metal sheet serves as a positive electrode and a negative electrode of the energy supply mechanism and is respectively connected with the controller and the energy storage capacitor, and the controller is connected with the energy storage capacitor. The concrete chloride ion sensor is fixed to a steel bar of a to-be-constructed component, the poured slurry reacts with the metal sheet to supply energy to the concrete chloride ion sensor, and the controller transmits detection data through the steel bar. A battery and an external power supply are not needed for power supply, the metal sheet is subjected to an oxidation-reduction reaction in the cement to generate current, and the de