The proposed system, based on a commercial off-the-shelf optical sensor, demonstrates reliable performance but is limited by the fixed positions of its spectral channels, which are not optimized for the particular optical properties of vanadium electrolytes. To address this limitation, we explore the challenge of optimizing both the number and placement of spectral channels to minimize measurement error. The objective is to propose a new optical sensor with strategically selected channels, enabling precise measurement of total vanadium concentration and SoC in VRFBs. By identifying the most effective wavelengths and minimizing the required number of channels, we aim to achieve the optimal balance between accuracy and affordability, paving the way for a disruptive customized optical sensor for VRFBs.