Vehicle won't start

[carguy]

My 2008 Pontiac Torrent shows battery at half charge but vehicle won't start. I have to charge battery first. Any idea of problem ?

 

[melsg5]

A fully charged battery is 12.75 volts, once you get into the 11's the vehicle may not start.
You could have an old battery. Have the battery fully charged and tested.
You could have an alternator that is not charging the battery. Have the charging system tested.
You could have a parasitic draw on the battery. Using an multi-meter determine the draw on the battery when all systems are shut down.