i took my steering wheel apart to check out this same problem.
yes you need to disconnect the battery and remove the airbag.
you will need a large breaker bar and a 16mm socket. the instructions linked above are what i used.
i took my "clock spring" mechanism apart. it was he** to get it back together. i do NOT recommend doing this. However, having said that, i put a ton of silicon grease (not liquid) inside and it cured the problem. every once in a while it comes back but then i just do a full left to right and back lock to lock turn and it seems like it must re-distribute the grease because the noise goes away immediately.
good luck.