Article "A High-Resolution Reflective Microwave Planar Sensor for Sensing of Vanadium Electrolyte" has been accepted to MDPI Sensors. Congratulations, Nazli and Kalvin! Abstract: Microwave planar sensors employ conventional passive complementary split-ring resonators (CSRR) as their sensitive region. In this work, a novel planar reflective sensor is introduced that deploys CSRRs as the front-end sensing element at fres=6 GHz with an extra loss-compensating negative resistance that restores the dissipated power in the sensor that is used in dielectric material characterization. It is shown that the S11 notch of −15 dB can be improved down to −40 dB without loss of sensitivity. An application of this design is shown in discriminating different states of vanadium redox solutions with highly lossy conditions of fully charged V5+ and fully discharged V4+ electrolytes.