is there a prob in this battery diy plan with prebuid case?

Batteries, Chargers, and Battery Management Systems.
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flippy   100 MW

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Re: is there a prob in this battery diy plan with prebuid case?

Post by flippy » Apr 17 2021 7:42pm

they are not fuses, they are PTC's. they protect the cell against overheating,pressiure and other assorted damage that might result in a "RUD". its a safety valve that opens the inner cell to the outside air and breaks the electrical connection.
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Dak77   100 W

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Re: is there a prob in this battery diy plan with prebuid case?

Post by Dak77 » Apr 17 2021 10:38pm

flippy wrote:
Apr 17 2021 7:42pm
they are not fuses, they are PTC's. they protect the cell against overheating,pressiure and other assorted damage that might result in a "RUD". its a safety valve that opens the inner cell to the outside air and breaks the electrical connection.
Will those pop in the case of an external short?

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Re: is there a prob in this battery diy plan with prebuid case?

Post by flippy » Apr 17 2021 11:56pm

Dak77 wrote:
Apr 17 2021 10:38pm
flippy wrote:
Apr 17 2021 7:42pm
they are not fuses, they are PTC's. they protect the cell against overheating,pressiure and other assorted damage that might result in a "RUD". its a safety valve that opens the inner cell to the outside air and breaks the electrical connection.
Will those pop in the case of an external short?
Only if the cell itself wold explode. So generally no. But per cel fusing is stupid and should notbe done.
PTCs are like spinklers, airbags or body armour. A last resort and using it means you got WAY bigger problems.
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Chalo   100 GW

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Re: is there a prob in this battery diy plan with prebuid case?

Post by Chalo » Apr 18 2021 1:04am

So why are you planning to use vape pen cells instead of cells that match the application?


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flippy   100 MW

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Re: is there a prob in this battery diy plan with prebuid case?

Post by flippy » Apr 18 2021 3:21am

batteries like the HE4 can handle more current then you would ever need without having pouches doing their "zwelgje" routine.
(aka: thats a cute little harmless cartoon dragon that gets larger, breathes fire and kils everyone around him when it gets angry)

cheap chinese pouches are never to be recommended, especially not to padawans....
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Re: is there a prob in this battery diy plan with prebuid case?

Post by want to build » Apr 28 2021 9:19pm

Chalo wrote:
Apr 18 2021 1:04am
So why are you planning to use vape pen cells instead of cells that match the application?


Image
chalo you are recommanding me rectangular cell instead of vtc4 sony exact? why exaclty? tx what are their cost and price, pros and cons

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Re: is there a prob in this battery diy plan with prebuid case?

Post by want to build » Apr 28 2021 9:21pm

flippy wrote:
Apr 18 2021 3:21am
batteries like the HE4 can handle more current then you would ever need without having pouches doing their "zwelgje" routine.
(aka: thats a cute little harmless cartoon dragon that gets larger, breathes fire and kils everyone around him when it gets angry)

cheap chinese pouches are never to be recommended, especially not to padawans....
hi Flippy, you are introducing the He4, never heard of it, my google search tell me those are 18650 cells. Is this what chalo was refering to? i mean his picture is rectangular.

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Re: is there a prob in this battery diy plan with prebuid case?

Post by want to build » Apr 28 2021 9:24pm

99t4 wrote:
Apr 14 2021 12:42am
want to build wrote:
Apr 13 2021 11:01pm
I know that is a lot of questions, i would apreciate if you could answer them all even if the answer is dont know.
OK, I don't know, for all the questions except for your question #10:
want to build wrote:
Apr 13 2021 11:01pm
10)Would you say that the point of suggesting me to read the link is to look at the image and not to suggest me going in the way of using fuse wire?
No, the point suggesting you read the link was mainly for you to see the image (BTW, not that image you referred to with all the numbers, but the one before it) to see where the center pin meets the bottom anode (-) cap, in the center, where it is not recommended to solder, or even spotweld. As you seemed to be unsure of the reason to avoid heat-stressing that immediate area.

I mentioned the (not)fuses, as, since that article was written, there has arisen some controversy on whether those are even in fact fuses. Didn't want anyone reading this in the future to get the wrong idea either.
Ok i draw a circle in blue . is this the spot you and goatman are talking about?
what is the problem there? is this center rod conductive or non conductive?
does it have a structural purpose or conductivity purpose. can you clarify? tx
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Chalo   100 GW

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Re: is there a prob in this battery diy plan with prebuid case?

Post by Chalo » Apr 29 2021 12:21am

want to build wrote:
Apr 28 2021 9:19pm
Chalo wrote:
Apr 18 2021 1:04am
So why are you planning to use vape pen cells instead of cells that match the application?


Image
chalo you are recommanding me rectangular cell instead of vtc4 sony exact? why exaclty? tx what are their cost and price, pros and cons
The point is, why build a pack with 52 cells when you could build an equally capable pack with 13 cells? Less work, fewer points of failure.
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flippy   100 MW

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Re: is there a prob in this battery diy plan with prebuid case?

Post by flippy » Apr 29 2021 3:15am

please stop with the "points of failliure" BS. its simply not true. especally not when you consider the short lifespan of pouches without a good compression housing.
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Re: is there a prob in this battery diy plan with prebuid case?

Post by want to build » May 01 2021 6:54pm

Chalo wrote:
Apr 29 2021 12:21am
want to build wrote:
Apr 28 2021 9:19pm
Chalo wrote:
Apr 18 2021 1:04am
So why are you planning to use vape pen cells instead of cells that match the application?


Image
chalo you are recommanding me rectangular cell instead of vtc4 sony exact? why exaclty? tx what are their cost and price, pros and cons
The point is, why build a pack with 52 cells when you could build an equally capable pack with 13 cells? Less work, fewer points of failure.
HI chalo, i m an open person always willing to learn. the truth is that i did not know they exist. could you paste the spec of the cell you talk about , their price and a short pros and cons of using them instead on 18650 and then I will try to bring back the questions of what is the problem with the rod in 18650 cause it is still :) a mystery for me ;) . You are welcome to share your info , please use facts and data so we can see what you mean .
I wonder what you consider point of failure, do you mean more welding so like more chances to do a bad weld?

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Chalo   100 GW

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Re: is there a prob in this battery diy plan with prebuid case?

Post by Chalo » May 02 2021 12:50am

want to build wrote:
May 01 2021 6:54pm
[could you paste the spec of the cell you talk about , their price and a short pros and cons of using them instead on 18650
I'm not recommending any specific cell; there are at least dozens of cells to choose from in the capacity range you want. Use a search engine on "lithium ion 10Ah cell" or whatever capacity you have in mind. The goal is to find prismatic, pouch, or larger cylindrical cells that will give you the Ah capacity you want in a single cell, so you don't have to weld bunches of them together in parallel.
I wonder what you consider point of failure, do you mean more welding so like more chances to do a bad weld?

Yes, more welds means more places to have a bad electrical or mechanical connection. But that's only one of the problems with using a relatively large pack built up from vape pen cells.

The 13S battery I use has no welds in it at all. The cells have threaded studs, and I attached small copper bus bars to them to put the cells in series.

If you weld the cells, you not only heat damage them to some degree, but your pack's performance can be limited by the connecting strips (especially with high current cells like VTC4).
This is to express my gratitude to Justin of Grin Technologies for his extraordinary measures to save this forum for the benefit of all.

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Re: is there a prob in this battery diy plan with prebuid case?

Post by eMark » May 02 2021 8:09am

want to build wrote:
May 01 2021 6:54pm
... what is the problem with the rod in 18650 cause it is still :) a mystery for me ;) .
The anode rod comes in contact with the center of the can end thus any soldering or spot welding should preferably be done off-center closer to bottom can edge than at the center. Whereas the protective (explosion proof) cathode cap more easily dissipates any excess soldering or spot welding heat due in part to an inexperienced novice builder with less than desirable equipment prolonging the weld time.

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Re: is there a prob in this battery diy plan with prebuid case?

Post by eMark » May 02 2021 8:19am

want to build wrote:
May 01 2021 6:54pm
... what is the problem with the rod in 18650 cause it is still :) a mystery for me ;) .
The anode rod comes in contact with the center of the can end thus any soldering or spot welding should preferably be done off-center closer to the can edge than at the center. Whereas the protective (explosion proof) cathode cap more easily dissipates any excess soldering or spot welding heat. Due in part to an inexperienced novice builder with less than desirable equipment prolonging the solder or spot weld time and cell damage.

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Re: is there a prob in this battery diy plan with prebuid case?

Post by want to build » May 11 2021 9:34pm

eMark wrote:
May 02 2021 8:19am
want to build wrote:
May 01 2021 6:54pm
... what is the problem with the rod in 18650 cause it is still :) a mystery for me ;) .
The anode rod comes in contact with the center of the can end thus any soldering or spot welding should preferably be done off-center closer to the can edge than at the center. Whereas the protective (explosion proof) cathode cap more easily dissipates any excess soldering or spot welding heat. Due in part to an inexperienced novice builder with less than desirable equipment prolonging the solder or spot weld time and cell damage.
are you sayin the center pin on my 28 april picture is an anode?
if yes since the bottom part of the cell is an anode to, what is the problem with welding on top on it?

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Re: is there a prob in this battery diy plan with prebuid case?

Post by want to build » May 11 2021 9:41pm

flippy wrote:
Apr 18 2021 3:21am
batteries like the HE4 can handle more current then you would ever need without having pouches doing their "zwelgje" routine.
(aka: thats a cute little harmless cartoon dragon that gets larger, breathes fire and kils everyone around him when it gets angry)

cheap chinese pouches are never to be recommended, especially not to padawans....
guys, i would like to ear your shoot on why the cells shown by chalo are not advised for inexperiences welder because he does make a point in saying i is more simple but i have to have the other side of the medal too.
is it because vtc4 have protection device pouches have not?
Chalo you can also tell the negative of the pouches you recommand to have a global view about them pros cons

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Chalo   100 GW

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Re: is there a prob in this battery diy plan with prebuid case?

Post by Chalo » May 11 2021 10:17pm

I don't know anything about those specific cells, except that they're in the Ah capacity range you were discussing. One of my batteries uses PHEV2 format prismatic cells with threaded studs. The other one uses a pouch cell pack from a Mercedes-Benz. I'd put the reliability and safety of either one above any pack made of vape pen or flashlight cells.
This is to express my gratitude to Justin of Grin Technologies for his extraordinary measures to save this forum for the benefit of all.

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