1985 toyota pickup charging system help?

So my 2 month old battery just died last night while i was coming home from work....crappy....and i already know what the root of the problem is. There's a cable that comes from the fuse box under the hood...that hooks up to the positive terminal hooking up to the battery....the connection on that sucks. What is that cable called and how do you fix that exactly...never had to deal with that...and electrical isnt exactly my strong point.