Battery Calibration

hi, i have an inspiron 1200 and 1.5 years old. My battery life has decline over the last few months from about 2 hours to about 30 minutes now, i had some power cord issues, but i think all i need to do is run the battery calibration utility, but i can not find it anywhere, it used to pop up once in a while on start up , but i cant figured out how to manually start it. Its now in the bios settings anywhere, nore can i find it anywhere in windows.

 

thnx in advance