check the wire conections to the battery specialy the negative side make sure is clean and tight
Alternator is not charging. Have it tested and/or replaced.
Have the battery and/or starter tested for free at your local auto parts store.
test the voltage on the battery first, then on the alternator. If its good then it could just be the diode in the alternator. I would suggest you replace it becuase eventually your alternator will die and the battery will not get charged leaving you stranded somewhere. It is possible to just be a battery but you wont know unless you have the battery tested. check the voltage on the battery and the alternator before you do anything else.
Diagnosis: Engine Won't Start or RunCheck related link below
Dead battery
Have the battery load tested at your local auto parts store, even though you think you have it charged it may be bad. Have the charging system tested also.
Could be a shorted wire, or bad battery.
more than likely it is your alternator, have it tested.
Dead battery. Recharge it and see if it will start. If not, remove the battery and go have it tested.
Yes first remove the old battery and be careful not to get anything wet then get your new battery and measure it up the masure the old battery gap then carefully insert your battery into the hole/gap
Anytime the battery light comes on there is usually a charging problem. Check the voltage output of the alternator with a digital multimeter at the alternator & battery (should be 13-14 volts) when running. Get battery tested to be sure it has enought cold cranking amps (spec is usually on battery label). Make sure the battery is tested properly, side post batteries are notorious for failing if they are tested through the bolts due to bad connections & corrosion. Could also be a loose connection that is affected by the motion of the car when you step on the gas.
You have a bad fuse or a shorted wire going to the headliner light.