"I am looking for an answer to this all oveer but could not find."
All over huh? Wow... that must of been an extensive search... I mean, its not like you could log in to linux questions, type "redhat 9 battery monitor" into the search feature and get... oh, wait, what's this.. 14 threads and 102 posts on that exact subject with complete instructions... hrm..
Congratulations on your search of "all over", when these very forums are so crammed full of this question that people are practically sick of it.