The Ring Imaging Cherenkov (RICH) detector of the Alpha Magnetic Spectrometer (AMS-02) measures cosmic-ray velocities and nuclear charges, enabling isotope identification in combination with the silicon tracker. After more than 15 years of operation on the International Space Station, over 95\% of its detection channels remain operational. We present the detector status, on-orbit calibration, and a new reconstruction of particle velocity and charge. The calibration accounts for variations in the aerogel refractive index and the spatial and temporal response of the photomultipliers. The reconstruction combines ray tracing of direct and reflected photon paths with maximum-likelihood estimation of the Cherenkov angle, while the nuclear charge is determined from the corrected photoelectron yield. Using flight data, velocity resolutions of \(\sigma_\beta \simeq 5.0\times10^{-4}\) in aerogel and \(\sigma_\beta \simeq 1.7\times10^{-3}\) in sodium fluoride are achieved for lithium nuclei. The relative charge resolution reaches about 4\% for heavier nuclei. These developments support precision measurements of cosmic-ray isotopes and the extension of isotope identification to heavier nuclei.