I would agree with FloodKillaz, battery's lifespan of charging from the alternator is roughly 3-5 years, depending on how many additional accessories you put on it. If you can by any chance, take it down to any dealership that offers a multi-point inspection and see if a battery test is mentioned in there. Most likely a dealership will use a M800 battery tester with a printout. It should determine what your battery's CCA, temp, volts, and CA's it is pumping. Did your battery start having issues after you installed the HID's?
Does the battery light come on in the dash? Curious to know if it is.
2009 Cobalt LS XFE U74
Mods: K&N Typhoon Intake, Option Cat-Back Exhaust, Cosmo Short shifter, Maxxim Ahead 17X7's, MPx shorty antenna, FE5 Strut/shocks, Tein S Techs, Moog endlinks, Moog spring seaters, ZZP shorty header, LSJ downpipe, LNF front grille