Batteries have become increasingly important in automotives with increase in vehicle electrical loads. Therefore the reliability of battery is a critical issue in automotive applications. It has been noticed that most batteries have limited cycle durability, that is, the total capacity drops when a battery is charged and discharged for a number of cycles. If a battery is too weak to offer sufficient energy, it should be replaced at the right time. But current problem is that there is no reliable method to quantify the capacity loss and to estimate the remaining capacity of battery. Complete discharge, which is the only way of capacity estimation, which will effect the battery plates therefore it cannot be used too frequently.This paper summarizes the experimental work in the development of the battery status estimation algorithm. The experimental work contains the battery parameterization of Lead acid batteries with different State of Charge, State of Health and in lower temperature (than room temperature) by applying worst case load in a vehicle.These experimental results can be used to estimate the status of lead acid battery.