How to attach 'Caps' to a cell ?

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ng.sa

Member
Joined
Apr 4, 2017
Messages
88
As I'm a newbie I have been buying stuff to see how it 'works'

I bought these caps

"
100pcs/lot 21700 lithium battery can be spot welded positive flat cap 20700 lithium battery pole piece DIY assembly parts
"

Basically because I couldn't see how they work from the net listing and then seller didn't reply to my query and I was bored during a lockdown due to .cn virus !!!

My original design was invert the caps. thread a fuse wire and then drop a pool of hot solder into the cap to 'capture' the fuse wire after they are arranged in a pack 'formation' before attaching to the cells. This would mean the cells are not exposed to the heat of the soldering :)

As my 2170s are genuine Mr Musk has already added a cap on the POS end, so I'm wondering how I could add a 2nd cap ?

- Do I shot weld ?
- Do I wrap ?
- Do I glue ?
...

Anyone using these caps ?

TIA
 

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Korishan

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Jan 7, 2017
Messages
6,548
Maybe post the link to where you got them, or post some bigger pictures of the caps. I'm not clear as to "why" you would buy the caps in the first place.
All they do is add a bump to the cell?
 

ng.sa

Member
Joined
Apr 4, 2017
Messages
88
G'Day K

Thanks for the really prompt reply

Maybe post the link to where you got them

That would be a waste of time as it is in China and I will bet that no one on here can read and write Chinese better than I can :)

I'm not clear as to "why" you would buy the caps in the first place.

Like I said "see how it works", try and innovate, push the techniques envelope, try something different !!!

I have read ppl saying - "Never solder cells" - from what I have read many ppl say that they believe that heat wrecks the cells

and it seems, just as many

"Never spot weld" - from what I have read, because spot welding cannot be Undone etc.

I know these are simplifications, so pls. don't correct me, I will be wrong to lots of ppl saying this


All they do is add a bump to the cell?

Yes I understand, but my idea is to add an electrical connection via fuse wire ( just like Elon does ) but not heat the cells with solder as the solder will be added before the caps are connected to the cells.

So then I need to work out how to add the caps to the cells ?

Anyone got experience connecting caps to cells ?

TIA
 

Korishan

Moderator
Joined
Jan 7, 2017
Messages
6,548
Ohhh, so these would be just to have a friction connection to the cell?? They wouldn't be firmly/permanently attached? I suppose shrink wrapping them onto the cell would keep them from moving. Problem is, there may be a lit of resistance between the disk and the cell.
Electrically conductive compound may work, but I'd be worried that on the Pos end it would get where it shouldn't.

That would be a waste of time as it is in China and I will bet that no one on here can read and write Chinese better than I can
This was more in line with more pictures perhaps. The one you posted isn't very detailed and it's pretty small ;)
 
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