Department of Electronic Technology, University of Vigo, Campus Lagoas Marcosende, Vigo 36310, Spain.
Sensors (Basel). 2012;12(8):10604-20. doi: 10.3390/s120810604. Epub 2012 Aug 3.
In battery applications, particularly in automobiles, submarines and remote communications, the state of charge (SoC) is needed in order to manage batteries efficiently. The most widely used physical parameter for this is electrolyte density. However, there is greater dependency between electrolyte viscosity and SoC than that seen for density and SoC. This paper presents a Quartz Crystal Microbalance (QCM) sensor for electrolyte density-viscosity product measurements in lead acid batteries. The sensor is calibrated in H(2)SO(4) solutions in the battery electrolyte range to obtain sensitivity, noise and resolution. Also, real-time tests of charge and discharge are conducted placing the quartz crystal inside the battery. At the same time, the present theoretical "resolution limit" to measure the square root of the density-viscosity product [Formula: see text] of a liquid medium or best resolution achievable with a QCM oscillator is determined. Findings show that the resolution limit only depends on the characteristics of the liquid to be studied and not on frequency. The QCM resolution limit for [Formula: see text] measurements worsens when the density-viscosity product of the liquid is increased, but it cannot be improved by elevating the work frequency.
在电池应用中，特别是在汽车、潜艇和远程通信中，需要了解电池的荷电状态（SoC）以实现对电池的有效管理。最常用的物理参数是电解质密度。然而，电解质粘度与 SoC 的关系比密度与 SoC 的关系更为密切。本文提出了一种用于测量铅酸电池中电解质密度-粘度积的石英晶体微天平（QCM）传感器。该传感器在电池电解质范围内的 H(2)SO(4)溶液中进行校准，以获得灵敏度、噪声和分辨率。同时，将石英晶体置于电池内进行实时充电和放电测试。同时，确定了目前理论上测量液体介质的密度-粘度积的平方根[公式：见文本]的“分辨率极限”或 QCM 振荡器可实现的最佳分辨率。研究结果表明，分辨率极限仅取决于待研究液体的特性，而与频率无关。当液体的密度-粘度积增加时，QCM 对[公式：见文本]测量的分辨率极限会变差，但通过提高工作频率并不能改善它。
