These eGo batteries have a couple of failure modes that can most times be overcome.
1) Clean off the liquid using something like a Q-tip or a paper towel soaked in alcohol. First aid isolpropyl alcohol works well as does Vodka. If you have none of these, try it dry. Try to get the threads clean so they make good electrical contact again. If you do it wet, let it all air dry for 5 minutes before proceeding.
2) What tends to happen is the center pin of the battery gets depressed too far if an atty or charger is screwed on too tight and does not come out again by itself. The battery is probably fine, just that center pin needs pulling up. It looks a little like a small button head, you should be able to get a pin or micro screwdriver under it slightly and pull it up gently, working slowly and gently around the head. This should bring it closer to the charger center pin allowing the battery to charge and the atty to fire properly again.
Here's a video of how it's done. Go to about 4:30 in the video for the good part
. Try charging the battery next. The charger light will be red while charging and will turn green when it's full.
If the battery pin turns out to have been pushed in too far, go easier when you screw on the atty and the charger. You only have to screw them on until they make battery contact.
Good luck with it!