the positive battery post has broke in half, it has happened twice this week,why on 1999 Chrysler Sebring

it has died several times just before we noticed the post problem.

2 answers
Wow, I can only suggest to replace the battery if you have not already. Have alternator tested to ensure proper charging of system. I have not heard of repeated post breaking issues before in one week.
You have a serious battery issue...highly recommend that you have a shop take a look at could be your alternator is overcharging but a shop will be able to verify this.