Application of flexible integrated microsensor to internal real-time measurement of vanadium redox flow battery

Abstract

The temperature distribution and vanadium flow rate distribution in the vanadium redox flow battery are the key to its performance. The reaction process in the vanadium redox flow battery is very complex, in the course of power generation, the uniformity and expendability of vanadium liquid distribution will result in nonuniform temperature distribution. Local high temperature will accelerate the ions through the membrane material, the vanadium electrolyte concentration decreases obviously, so that the overall generating efficiency of vanadium redox flow battery is influenced. On the other hand, under the limitation of low flow rate, the waste heat generated by vanadium redox flow battery is unlikely to be carried away by the flow field, so that the internal temperature of vanadium redox flow battery rises. On the contrary, in the condition of high flow rate, the waste heat in the vanadium redox flow battery dissipates rapidly, the temperature is low, the vanadium redox flow battery efficiency is increased slightly, proving that the flow control is also important to the vanadium redox flow battery performance. However, the authentic information inside the vanadium redox flow battery cannot be obtained accurately and instantly by outside, theory and simulation at the present stage. Therefore, according to the requirement for technical application of internal real-time microscopic diagnosis to vanadium redox flow battery, this study proposes using micro-electro-mechanical systems technology to develop a flexible integrated (temperature and flow) microsensor embedded in the vanadium redox flow battery for real-time measurement. The advantages of this technology include: (1) compactness; (2) flexible measurement position and accurate embedding and (3) accurate measurement, high sensitivity and quick response.