Punched Thru Cell Post Terminal Bottom

[MadMacks]

I recently got a call from a friend that was building a small 12v battery and was having issues with getting it to work. There were a variety of issues that I helped him fix, but I noticed that he’d purchased bolts for his cell bus bars and hadn’t used studs with nuts. The bolts he was using were around 1/2” long and I was concerned that he might have bottomed them out and punched thru the bottom of the threaded holes. The battery seems to be fine, but it does look like he may have done that in one or two of the cells.

So…question…assuming there may be cracked bottoms in some of the terminal post, what, if any, problems might that cause? If the post is filled with a proper bolt and tightened up would that reseal up the top of the cell? Or should the cells be replaced if they are in tact punched thru? I’ve never seen a discussion about this so I thought I’d ask…

 

[Lt.Dan]

I would definitely assume the threads would get ripped out of the terminal before the terminal cracked. The threads are butter soft, and are very well known for getting pulled very easily.

If the terminal is cracked or anything, I definitely would discard the cell and prevent usage.

 

[GerardJacinto]

It looks like I am in the same boat. I was in the process of preparing to top balance my 120ah cells. Noticed that one of the cells has its positive terminal thread is loose. Was not using studs.

I have studs now to replace the screws. So I drilled the positive post to widen it and insert a helicoil. Have done it before on another cell bit this time I drilled too deep and now there is a hole exposing the whatever is in the cell.

Has anyone tried to still use a battery cell in such condition? I am thinking of continuing to insert a helicoil and use a sealant? Loctite? Then screw in the stud with loctite sealant too?

Thanks in advance for any inputs.