Battery issue?

So, I had a battery issue and took it out and let it sit on the charger all night. The voltage was go ik d. So, I went to reinstall it today I did the cables that are on the battery hooked then up positive then negative. Then I went under the hood to hook the top ones up an did positive then negative and when I went to do the negitive the negitive touched its ground wire that it typically attached to and it arched an tried to catch fire. Any ideas?