you could have a bad alternator. the battery cant handle all that voltage alone. you might want to go to autozone or somewhere like that and have it tested.
"Let's get a little mud on the tires!"
'99 wrangler TJ 4" RC lift, 33x12.50 GY duratrac's, Banks Monster Catback, Warn M8000
'07 JK 4-door Rescue Green 3" RC lift, 33x11.50 Nitto terra grappler (dad's)