State of health for automotive batteries

摘要

Described is a method and apparatus for determining the state of battery life of a starting, lighting and ignition (SLI) battery comprising; 1) determining the number of starting engine cranks the battery has performed and comparing that number with a desired number for starting engine cranks to ascertain a state of health of the battery, calculated as a percentage of the desired number; 2) determining the percentage of battery life diminished due to battery exposure to a maximum temperature and the minimum state of charge the battery has been exposed to at that temperature, calculated as a decrease from 100 percent; and 3) calculating the lower of the values of step 1 or step 2 thereby determining the state of the battery life.