Exactly, but when your making mtb packs, you got to print your own 
(half of a 16s battery)
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When making a boxed (mtb) battery, is it more common to get cell holders for the pack or just tape/glue it all together like normal?
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I havenāt used cell holders because most of my builds are squeezing the most cells in the box as possible. It depends on what you are working with.
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Mmm fishpaper xxx
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ive seen many established builders on here do it the exact same way i did. ive seen from pics they sent me when they built my batteries that they did it in the same way i did. when the nickel is folded the cells barely get warm.
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Nickel doesnāt have the mass to heat the cells, it simply canāt transfer any heat to them worth worrying about.
Itās easy to test this hypothesis if you have a temp gun.
Yes, that method is perfectly fine when doing it to fresh cells.
Your cells were already heated pretty bad from your first time soldering. The amount of heat that you will have had to put into that folded nickel strip to get good solder joints is enough to put even more heat into your already damaged cells. You didnāt even bother to prep the nickel with solder pads first, for Peteās sake.
Every single thing I (and others) have said to you about that pack since you first posted pics of it were about how to limit the amount of heat you put into those cells.
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Iād say it depends on how long of a piece of wire is being attached. Itās mostly just funny that he did the opposite of what he said he would
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I dont agree.
I have soldered lots of nickel folds like this, and if I take too long making my solder joint then the nickel directly above the cell terminals absolutely gets hot enough to burn my skin/boil water.
Thatās why doing things like prepping the nickel with solder pads is so important, because it cuts down on the amount of time you spend heating up the nickel to get a good solder joint.
Iām very interested to see your data, please tag me when you post it.
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I just would have soldered before bending the tab over. So that it was flat instead of vertical and hanging in the air.
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The nickel is acting as a heat break. Like a fuse. Itās only so conductive. Just like it can only send 10 amps of current, it can only send an equal amount of thermal energy into the cell.
You are familiar with heat breaks? A 3d printer has a good example of a heat break. Itās the very same principle.
Sure, Iāll make a video debunking this ridiculous myth. Iād be happy to.
edit: sorry I lost my patience here a little. Iām working on it.
Not so true, depends on the person soldering and your iron, in my first days i would heat up the cells easily while soldering the battery cables with a shitty iron, but then i got a 200w weller w201 soldering iron, with a thermal mass to heat up a small room in 20 mintues of on time, and i can solder without heating up the cells, because the connection is made in 3 seconds or less of the iron actually touching the nickel/cell
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would love to see this video. i agree with both you and Ben. To stay on the safe side we try to keep as much heat away form cells as possible, however i totally see your point and i agree a lot of times i donāt see any heat worth worrying about when soldering to nickel that is welded to a cell
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So how long do I have to keep the gun on the nickel to heat the cell? Any guesses?
Depends on the soldering iron, but a general rule is dont heat up the cell, so try to do it as quickly as possible, or solder before, which i personally dont like.
The way i usually do it, add a blob of solder to the tab
preheat tinned wire
bring the hot wire and just touch it for a second to melt in the nickel blob
a smaller 60w iron maybe 10-15 seconds? i guess
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I can solder it almost immediately with my setup, so Iām going to have to hold it on there longer than I would normally need to. The trick, if any, is using a really hot iron. That way, you donāt have to loiter.
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Wellā¦
If the nickel, as you say, simply canāt transfer enough heat to the cell to be significant, then the time of the soldering operation would be irrelevant. No?
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Gosh no. Why would it be irrelevant? Iād imagine you could heat up the cell with tabbed nickel, but I think it would take ages. Time is incredibly important. I say it canāt heat up the cell because I expect people to be able to solder within a given timeframe thatās less than what it takes.
Itās going to take me a little while to get everything setup. I have to charge my lipos, weld a tab onto a cell, and make a video. Give me a little bit.
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