Wow you’re not going ask us to like and subscribe in the video? Click the bell? Road to 1 million subs or nah?
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Guys, hi, just a quick question. I have exway Atlas with 12S3P (518 wh) and I’ve heard that someone in China tried to swap battery in it to a 12S4P molicel (700+ wh). So I was wondering whether it is possible to build an extended 12S4P pack but within the same dimensions (48.5x16x3) as there is no free space there? The idea is just to swap the pack and keep everything else stock. Thanks.
Its not really possible, if the height can be a bit taller you could DS 18650 and fit a pretty massive pack in there but as they are there you’ve basically got the best pack bar using weirdly sized larger cells or something.
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What width the preferred nickel width for a 12s9p staggered 21700 p group? I feel 30mm would be too wide since the inner diameter of the positive terminal is around 11m. Seems like I need around 22mm but I don’t think that is a readily available size. I can find 20mm, 25mm, 30mm and 27.5mm. I’ve long forgot my trigonometry 
I’m planning on 2 pieces of nickel: one piece folded over the the first row and a second piece over both rows of cells.
Thank you, amigos.
Here’s what I’m trying to build / mimic.
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Well shit. Saw you’re doing 9p.
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Using that would make my life a lot easier!!! I could live with a 12s8p too. I’m not sure it will fit very well inside the Flux and may cause rubbing between the deck the battery. 
So decided to stagger instead of double stack.
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If 9p fits currently, 8p will fit as well.
The flux enclosure is 4cm deep + 6mm foam gasket
8p double stack is 21mm * 2 = 4.2cm (so I will need to build a gasket which is not the end of the world)
9p is staggered is (21mm * 2)/sqrt(2) = (21*2)/sqrt(2) ~ 3.0 cm and plenty of room for wires etc. Did I do the math right?
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Ideally you want nickel wide enough to cover both the top and bottom layer of cells, and even more ideally have enough left over to fold over to make a tab on top.
Since a stagger-stack 21700 group is 41.05mm tall, you probably want a minimum of 30-35mm wide nickel to cover both layers. 50mm would be extra-nice because it’ll cover everything, and give you extra for a tab.
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Thanks @MysticalDork I did the math wrong (60 degree angle vs 45). I need 42mm*.86 ~ 35mm. I will try to find a 50mm and avoid nickel on nickel welding.
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50mm is ideal for this.
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me after buying 100 more cells when there are like 150 sitting in my closet
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you go say sorry to those cells right now.
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why
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At least tell them someone wants them.
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oh they already have a home lol. I’m making some portable onewheel batteries that could be found on youtube.com/mariocontino
not worth using p42a on those as they only drain like 5-8ish amps depending on the voltage diff
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they actually never have a case for 12S BMS, So they use the 16S case for the 12S one. that is why larger than the 13S one.
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why dont they use the 13s case for the 12s?
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My guess is that since 13s is a very common ebike voltage, the 13s BMS use a different, dedicated, 13s-only controller chip.
The 16s ones use a chip that does support bypassing channels to support other oddball configs, but I guess the 13s one doesn’t.
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