METHOD OF ESTIMATING INTERNAL RESISTANCE, METHOD OF ESTIMATING CHARGED CONDITION, AND METHOD OF DETERMINING START OF ENGINE

摘要

PROBLEM TO BE SOLVED: To provide an internal resistance estimating method capable of estimating internal resistance precisely at a low cost. SOLUTION: In this internal resistance estimating method, current values, voltage values and temperature values of a lead-acid battery are measured in three different time points, parameters a, b are computed based on an inequality of 0.7,4η/T)-exp(-1.1x104η/T)]<1.3, whereη=b-E+(IxRohm) (S200), and the current value, voltage values and temperature value in the present are measured (S202) to calculates the internal resistance Rohm based on the inequality (S204). The internal resistance of the battery independent of the current is obtained by this manner. COPYRIGHT: (C)2004,JPO