Fibre optic reflective sensor to measure state of charge of battery
Harpreet K. Bal, Victoria University (Australia), Zourab Brodzeli, University of New South Wales (Australia)
A low-cost, high-accuracy fibre optic sensor of state of charge (SOC) of battery is demonstrated. It is based on the measurement of the refractive index of the electrolyte of the battery by monitoring intensity of light reflected of one of cleaved ports of fibre optic coupler submerged into it. The output of the sensor was calibrated to any temperature fluctuations to discriminate between refractive index change due to decomposition of sulphuric acid and due to increase of temperature.
