METHOD OF DETERMINING RESIDUAL CAPACITANCE OF LEAD ACID BATTERY Russian patent published in 2009 - IPC G01R31/36 

FIELD: physics; measurement.

SUBSTANCE: present invention is meant for determining residual capacitance of a lead acid battery during its operation, and can as well be used in predicting residual capacitance for the expected value of discharge current before the short mode begins. From the periodically determined values of discharge current during the discharge process of the lead acid battery, as well as values of voltage on used batteries, electrolyte density and the number of the conventional complete charge-discharge cycle, two values of residual capacitance are calculated using the relationship between residual capacitance and discharge voltage and between residual capacitance and electrolyte density. The parametres of the relationships are determined using auxiliary graphs, which are plotted first from values obtained from approximating graphs obtained using data from testing batteries of the same type. For visual representation of the discharge process when the battery is working, two graphs are plotted for calculated values of residual capacitance versus the measured capacitance, which enable visual monitoring of the process of changing residual capacitance and confirm accuracy of the obtained values of residual capacitance. The resultant residual capacitance value is determined as the arithmetic average of two calculated values of residual capacitance.

EFFECT: more accurate measurement.

7 cl, 10 dwg