My guess....either bad alternator or bad battery.

around the plug holes at the top? that could be a sign of an alternator working overtime and overcharging the battery. if not, it might just be a bad/dying battery...

sP

leaking out of the battery. If it's gotten to this point, it would be best to replace both the battery and the cable. If you take the connector off the cable, you will probably find the copper wire is also corroded for a few inches in. This corrosion adds resistance in the cable and stresses the battery and everything else in the charging system.

But, you can get a little more life out of it if you clean the terminal and battery post and when you put it back cover the whole thing with Vaseline.

before she's stuck somewhere without your help. I fought that fight with vaseline and then went to an auto store to get felt-type rings to put around the posts and even changed the cable. Nothing to do in the end but replace it and be done with it for another 200k miles. If that is the original battery you got your money's worth out of it.

Run the car for a while, or drive it around. Then carefully check to see if the positive post is hot. If it is then one of the connections is not good.

Clean the terminal(s) with baking soda and water. Be careful, be sure to disconnect the battery properly and keep the cables away from contacting anything. When clean and rinsed, coat the terminals with a little Vaseline.

If it occurs again, see a mechanic. It may just be that a new battery is needed, but with electrical, it never hurts to get expert advisement.

Hope your daughter's vehicle is right as rain with the least monetary hit possible.

As lead acid batteries age the positive plates inside the unit tend to grown this can cause the post to be pushed up against the case top breaking the seal releasing acidic fumes which corrode the post and terminal.

The use of the felt pads and grease can give some temporary relief but if the + plate growth becomes excessive the top of the case may crack.

the question is why. My guess is you're overcharging, which means the voltage regulator has gone out. This'll create pressure inside the battery that has to go somewhere, like out the seal around the positive post. And these days, regulators are internal to the alternator.

Alternators are REAL easy to get out - unhook the battery first, then remove the two wires coming off the alternator, loosen the top bolt, swing the alternator over so you can remove the belt, then remove both bolts and lift out the alternator. Installation is the reverse of removal. Carry the alternator to the nearest auto parts place and have it tested; if the VR has gone out, buy a rebuilt alternator and install it.