I have an OM-4t, an OM-3, an OM-2sp and OM-PC which are all known for battery longetivity issues.

Since all these are seldomly used I have taken the habit of removing the batteries between uses.

I use a copper penny and softly open the covers to avoid damage. plus I don't see any need to crank down with all my might when closing them up. (it's not like they will spring a leak)

So far this works great for me. I'm not killing batteries needlessly and the fresh ones just go into the camera in use at the time.