Online Spectroscopic Study on the Positive and the Negative Electrolytes in Vanadium Redox Flow Batteries

<table>(a) The schematic of the spectroscopic online electrolyte analytical system when online detecting the positive electrolyte of a VRB. (b) The schematic of the same system when online detecting the negative electrolyte of a VRB. VRB: a vanadium redox flow battery; Battery: the battery stack of the VRB; T1 (T2): the positive (negative) electrolyte tank of the VRB; Pump 1 <svg height="15.0875" id="M3" style="vertical-align:-2.3205pt" version="1.1" viewbox="0 0 20.049999 15.0875" width="20.049999" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg>: the pump of the positive (negative) electrolyte; Tester: a charge-discharge tester; LS: a white light source; BS: a beam splitter; Cell: a 0.5 mm thick absorption flow cell; SP: a grating spectrometer; D1: a photo detector; D2: a cooled CCD camera; PC: a personal computer.</table>

Journal of Spectroscopy

fig1

Figure 1

Figure 1: Online Spectroscopic Study on the Positive and the Negative Electrolytes in Vanadium Redox Flow Batteries 