METHOD AND SYSTEM FOR DETERMINING BATTERY STATE OF HEALTH

A battery fault detection system includes a battery providing a battery voltage signal, and a detection circuit. The detection circuit includes a steep drop detector circuit constructed and arranged to detect a first occurrence of a steep voltage drop of the battery voltage signal and establish a time window, with the steep voltage drop detection defining a first condition; a slope measurer circuit constructed and arranged to measure positive slope values of the battery voltage signal; and a slope comparator circuit constructed and arranged to compare a measured positive slope value with a reference voltage and if the measured positive slope value is greater than the reference voltage, a second condition is defined. The detection circuit is constructed and arranged to indicate a properly working battery only upon the occurrence of both the first and second conditions.