Can you supply me with the maths on why there is stress on the welds because i dont see any myself
The deformation is a plastic one, the nickel does not fight back to straighten itself so the force is 0
I think he only means when there is multiple layers, one layer will need to āextendā and one layer will need to compress, which causes a shear force on the welds between the layers. For single layer im not sure there is any real stress.
In another note, I donāt feel like its really necessary to do multiple layers of nickel on the folding part, one layer and the current travels a very short distance. If the pack is properly compressed, the nickel should be touching on both sidesā¦
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If you use multiple layers for the serial connections than the upper nickel will bend less than the first layer means there is stress on the first layer of nickel.
I hope thatās somehow understandable without drawing it 
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Especially on packs which are 5p plus thatās very true.
And yes you got exactly what I tried to say.
I have seen packs made like this even on commercial boards which fails exactly out of this reason (maybe not only the bending but also a not proper nickel to nickel weld, but thatās all can add up)
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Short cables could help there
Kinda like how on the new MacBooks the display cable is longer by a cm or so, the extra force is enough to break the cable overtime with just regular use.
Did exactly that and worked perfectly 
Thanks!
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The carts that i see that 12x0.2 can do only 15A is totally wrong, because those charts were made by engineers who thought if the nickel heats up anything maybe even as little as 10 15c was too much energy loss
A guy on here did tests with currents and measured the temperatures and if I remember well he got to 35A for 10x0.2 and it was at only 65C (30Q gets to 80c at 20A continious)
So our nickel can handle way more amps, he should post a chart with his results soon
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Iām about to join two 6S4P banks into a larger 12S using a copper braid to join them. The battery has flex but it will be in a haya so no felx in the deck to worry about. Itās been a good while since Iāve soldered anything but i got a ts100 for christmas and most of what I need. Anyone have any tips for soldering braid or better yet a video? Battery was not made by me but seller didnāt feel comfortable shipping it soldered which I understand.
Agreedā¦ fold = bad. I see no reason to introduce more metal fatigue if wires can go between buses on the halves.
Ignore the ugliness - I recently tore apart my first battery from last year (BMS failed) and itās the best example I have of where I avoid folds.
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āavoid foldsā
picture of bunch of 90 degree nickel tabs
adds thickness to the battery, more connection points = more failure points, more chance of tabs wearing through insulation and shorting against cell casingā¦ A single fold adds negligible fatigue, just my 2 cents opinion 
I should have been more specific. A completely folded piece of nickel is significantly weaker than a 90-degree fold. Ideally, the radius of the bend is also larger on the fold around the edge.
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Thatās why I suggested using a piece of cutting board or something between the fold, increases the radius of the fold
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Not sure if this is the right place to ask but why do AS150 and XT150 have different size bullets? It seems on high capacity batteries, they tend to come with one AS150 (positive) and one XT150 (negative) which prevent connecting batteries in series easily. Why not have both be AS150? Give the choice, is there anything wrong with going with 2 AS150?
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Having the female and male connector on a battery makes it easier to connect in series but it also makes it easy to short a battery.
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Theyāre both female on this battery that Iām considering getting
You do make a good point however; itād be really easy to connect the battery backwards
When I solder braid, I clamp it on both sides with something metallic to act as a heat sink. Lay a strip of solder that wets the braid along the cut you want to make. When you cut it it should not fray. Then use another heat sink when you solder the braid in place to keep the solder from wicking too far.
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interestingā¦
https://spectrum.ieee.org/energywise/energy/batteries-storage/a-lithiumion-battery-that-bends
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No really. This is essentially every lithium battery in existence.
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