We have one guy that answers to the Maint Manager per shift that is the battery change guy. He is trained on battery change, fill, gravity checks, cell V checks, washing etc etc.... When not changing batts he does "light" maint jobs. When gone on vacation/sick etc... One of the entry level building maintenance guys will fill in for him. I also have no issue with covering the battery room from time to time... LAst boil over spill we had was 8+ years ago when dumb dumbs were still doing batteries.