Refractometric fiber optic sensor for in-situ monitoring the state-of-charge of a lead acid battery

Patil, Supriya S., Labade, V. P., Kulkarni, N. M., Shaligram, A. D.

Publication in Journal of Optical Technology

For Russian citation (Opticheskii Zhurnal):

Supriya S. Patil, V. P. Labade, N. M. Kulkarni, A. D. Shaligram Refractometric fiber optic sensor for in-situ monitoring the state-of-charge of a lead acid battery [на англ. яз.] // Оптический журнал. 2014. Т. 81. № 3. С. 61–66.

Supriya S. Patil, V. P. Labade, N. M. Kulkarni, A. D. Shaligram Refractometric fiber optic sensor for in-situ monitoring the state-of-charge of a lead acid battery [in English] // Opticheskii Zhurnal. 2014. V. 81. № 3. P. 61–66.

For citation (Journal of Optical Technology):

Supriya S. Patil, V. P. Labade, N. M. Kulkarni, and A. D. Shaligram, "Refractometric fiber optic sensor for in-situ monitoring the state-of-charge of a lead acid battery," Journal of Optical Technology. 81(3), 159-163 (2014). https://doi.org/10.1364/JOT.81.000159

Abstract:

In-situ monitoring of the state of charge (SOC) of a lead acid battery is important to understand the residual electrical energy. Usage of the battery reduces the charge content of the active electrolyte which in turn changes its refractive index. This paper reports a refractometric fiber optic sensor developed for on-line monitoring of SOC. The sensor is designed in such a way that it can be easily fitted in any cell of a lead acid battery. The SOC of the battery is estimated from sensor output. The battery performance parameters of the battery, such as terminal voltage, discharge current, ampere-hour, battery temperature, SOC and depth of discharge using the fiber optic sensor output of the battery are monitored for a given electric load. The data is recorded continuously by a data acquisition card USB 6009 using the Lab VIEW Platform. Concurrently the specific gravity of the active electrolyte is measured using the suck type of acidic hydrometer. The set of experiments are carried out for different discharge currents by varying the electrical load and the SOC of the battery is monitored. After comparing the results for the SOC of the battery with the conventional methods, such as coulomb counting, terminal voltage and acidic hydrometer, it is concluded that the developed sensor output is a direct measure of the SOC of the battery.

Keywords:

fiber optic sensor, state of charge of battery, lead acid battery, refractometric sensor

Acknowledgements:

One of the authors (SSP) wishes to acknowledge the Head of the Department of Electronic Science, University of Pune, for allowing the use of laboratories for the work. She is also thankful to the Principal, Fergusson College, for providing the necessary laboratory facilities. The author also expresses sincere thanks to UGC, New Delhi, for the sanction of a teacher fellowship and the Principal, Dr. S. G. Gupta, and authorities of Abasaheb Garware College, Pune, for granting the study leave.

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