+1
If it takes a new model…. go for it. 
well i want a charger with build it flashlight. 
we got many flashlights with build in charger already
Hey guys, I got Mike’s 30Q’s in and they are reading inconsistently. They are mostly under 100 milli ohms, but one is a bit more erratic. I took off the extra wrapper and I ran into a problem.
It seems Mtn Elec button top 30Q are spot welded in 4 points. This should be the most reliable method of attaching a button top and give the least amount of extra resistance, but appearantly it’s not.
Now I’m trying to figure out the best way to remove it without damaging the factory wrapper.
Any suggestions?
Hey, I found the problem! It looks like the spot welds did not penetrate enough. I was able to take a micro screwdriver and pry underneath the tab and it popped right off. That would definitely explain the extra resistance. Now let’s hope the other three cells are just as easy. (EDIT, they were not)
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Well………it seems that this might answer some of our questions.
Okay, after cleaning off both ends of each battery I tested them out in my own C4-12 charger three times each and they all read very consistently with low internal resistance and they all automatically switched to the 3 amp charge rate.
35 47 27
27 34 44
39 43 32
31 33 39
27 to 47 might seem like a big swing, but for this charger I’d say it’s more than fine.
Now to do the solder blobs. I don’t expect the resistance to change any but I’ll test each cell multiple times afterwards just to confirm.
With solder bobs , how would you make sure they all make contact in a Q8?
All you have to do is make sure they are taller than the wrapper. I plan to go a bit taller than usual above the wrapper just in case they wear down a little due to rubbing the brass ring on the Q8.
Following
As my ole granpappy used to say Jason……
…………………………… “that’s some mighty fine work son!!” :+1:
And it is some mighty fine detective work too!! Good job Jason…… 
You proved / verified at least three things I believe.
- 1. Your are a pretty good detective.
- 2. The problem was indeed with the cells from MTN & not the charger.
- 3. Mike is not crazy.
….
Almost 4 years ago I tried to raise the possibility that it wouldn’t be a good idea to add button tops to high drain cells
and elsewhere on this forum when I brought up the subject I was ignored. High drain cells are made with flat tops so that they can be spot welded into battery packs. Those spot welds connect the cell directly into the pack, not onto a button top that has to make relatively loose contact with another conductor. Also those spot welds are very large and robust.
This question of high IR with added button tops has been coming up over and over again on this forum. Here are some links to other threads that were started on this subject.
Solved: Internal resistance increase with button top VTC6 and 30Q
Anyone else had dud Samsung 30Q button tops from BG recently?
So yea. Whatever you guys do, don’t use magnet battery spacer… buy a button top or solder blop.
This is an example how much heat generated from a flashlight.
The other three cells, which were giving better resistance readings, turned out to be a bit tougher to get the button tops off. I got them off though. The pink shrink wrap got a little damaged, but it’s just cosmetic. I think I’ll add a clear shrink wrap layer to protect it.
The Mountain Electronics cells are genuine, high quality 30Q. The question is, who added the button tops for Richard? I will ask him about it.
These spot welds seem to be right around the edge of the battery post. If the button tops were a little smaller in diameter it would move the spot welds to a nice flat area. Then they also need a bit more penetration.
My button top 30Q I got from Banggood seem fine. I didn’t look close at the spot welds, but it was on good flat surfaces. I assume it was a beefier weld.
Eh, sometimes button tops are fine, sometimes not.
I’ve seen some people solder little copper discs punched out of a sheet. I wish I had some of those.
So are these cells safe to use in the Q8 “as is”?
Yeah, those are the numbers I also get from my unprotected 30qs and LG H2s.
You can’t use flat tops in the Q8. The positive posts need to be raised.
My thoughts exactly.
Well you can… it will ruin the top plastic cover.
Now it has become ‘smart’ again after it was proven that the button-tops were the culprit of the high and erratic IR readings, as posted by JasonWW in post # 482.
I for one is a rah-rah boy of this charger, and I own a lot of other chargers.
After bending the negative tabs a few times to make better contact with the 26650's, my C4-12 is working ok too.