Patent ID: 7982457

Claim:
A method and eddy current system for a non-destructive, non-contact determination of resistance between the current lead stripe and the coating during the fabrication of chemical power sources including batteries, supercapacitors, photovoltaic cells and the like, said method comprising the steps of: placing an integrated measuring transducer over the surface of the coating on a metallic current lead stripe in the region of the shaft guiding the stripe movement so that all the points on the operating surface of the transducer are found at an identical distance from the stripe surface; measuring the relative effective resistance of the first eddy current probe of the integrated measuring transducer whose operating surface current lines are parallel to each other and are directed along the direction of movement of the current lead stripe, with the direction of the currents in the parallel wires lines being identical; selecting an operating frequency for the first eddy current probe that corresponds to the minimum frequency dependence of its added real component of the complex impedance; measuring the relative added real component of the complex impedance of the second eddy current probe of the integrated measuring transducer whose operating surface current lines are parallel to each other and are directed along the direction of movement of the current lead stripe, with the direction of the current flow in adjacent parallel lines being opposite; selecting an operating frequency of the second eddy current probe in the post-extremum region of the hodograph of the impedance added by the current lead stripe without a coating so that the value of the added real component of the complex impedance would not exceed 10% of the maximum value; detecting the value of the relative added real component of the complex impedance of the second eddy current probe caused only by the eddy currents flowing in the coating layer; synchronizing the measurements of the first and the second eddy current probes taking into consideration the speed of the uniform movement of the current lead stripe so that both probes would perform measurements on the same area of the coating; updating the value of the relative added components of the complex impedance measured with the first eddy current probe using the detected values of the introduced effective resistance of the second probe; determining the value of the contact resistance between the current lead stripe and the coating at various points along the stripe as it moves over the guide shaft while using the updated values of the relative added real component of the complex impedance of the first eddy current probe.