K-5, possible to use a Nikon battery in it?

I noticed that the battery compartment of the K-5 only has two conductors, positive and negative for the battery. The center conductor has a hole in the plastic of the casing of the camera, but isn't populated. I've been thinking about cutting the plastic lock in the caseing to allow the camera to use Nikon en-el3 or 3e batteries just to have the option of going into a store and being able to buy a battery for the K-5 off the shelve if needed. I also thought it might be good to have this option if the next camera body moves to another battery.

Of coarse I don't expect anyone to have done this, but it doesn't hurt to ask. So has anyone removed the lock and tried a battery other than the DL-190 in the camera?

Thank you
Russell