I want to install a Battery Tender harness on my 2013 R56 Hardtop. The problem is the negative terminal nut does not come off due to a retainer.

Is there a clean way to install ring terminals on OEM battery terminals?

 

Sandwich the ring w/ another nut.

 

I'm not following What do you mean, does not come off?

How would you change the battery then?

 

The nut that tightens the negative terminal on is designed to not completely back off the stud so you don't lose it. The stud thread ends are flared. This will also prevent threading a new nut on to "sandwich" the ring terminal.

 

Cut out a portion of the ring terminal so that it resembles more of a spade terminal. Then you can back off the battery terminal nut a bit, slide the quasi-spade terminal in place, and then tighten the battery terminal nut back down.

 

I was starting to think that is a good way to do it.

 

Now I see what you mean, I just looked at my 2013 coupe. .

As posted, just cut off a little from the ring and slip it in. Or cut off the battery tender connector completely and buy a new type connector and crimp on.