yeah basically. this is why the Mooch ratings are so valuable. just pick the best rated cell that fits your use case.
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The easy way is to use the Wh from moochâs âE-scoreâ. The whole point is that he does the integrating I talked about for you. That is why labeled capacity doesnât really matter. If the battery stays at a higher voltage longer it will have more total energy even with the same or possibly less Ah. You can try to integrate under the curves yourself by estimation if you donât like the 3.2 V cutoff he uses. Iâm not actually 100% sure why he chose a 3.2 V cutoff and if that is more for vapes or something. That would be a question for @Battery_Mooch. Anyway if you want to do a better job than using Ah youâd need to integrate or estimate the integral of those curves and use that to calculate range.
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The rated capacity numbers are for when youâre drawing some tiny amount of current, like a phone battery bank would. Thats when you can listen to advertised capacity. While under heavy load, delivered energy down to ___ voltage (usually 3.2v) is what you wanna look at.
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pretty sure this is for safety/datasheet reasons, something to do with cycle life
many in the vaping community will run their cells as low as 2.8V or 2.5V, as will many in the PEV community.
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3.6Wh * 12(serial) * 3(parallel) = 129.6???
i think i have a knot in my brain 
now multiply that by the number of cells in parallel.
3=Ah
3.6=V
the formula is:
Wh = (S x V) x (Ah x P)
S = Cells in Series
V = Cell Voltage
Ah = Cell Ah
P= Cells in Parallel
so for a 12s3p of 30q cells that would be:
12s x 3.6V x 3Ah x 3p
43.2V x 9Ah
388.8Wh
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that calculation i get
in case of using the Wh measurements of a single cell from Mooch, i donât get how to add it up to the whole pack
an easy way is just to multiply by the number of cells total in the pack.
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okay, i think i get it
it is off, because weâre only looking at the range till 3.2V in moochs test, therefore leaving some Wh that get calculated in when using the datasheet
This internal layout turned out really clean, I like it!
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the great thing about Moochâs numbers is that theyâre generally pretty conservative. meaning if you do your calculations based off his numbers youâll always get more than you expected.
itâs much better than building a pack to the maximum specs that can be calculated, and being disappointed when itâs even 5% less than the highest number you calculated.
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I used Velcro. Velcroing the cells down
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Very nice. I hate butyl tape for sealant though. Only good for maybe one or two separations. Window sealant tape is much better imo. Are the series connections directly soldered onto the parallel connection on the cells or is it folded up beforehand?
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Itâs a good conservative number for general use as there is typically little charge left in the cells below that to affect any delivered-Wh differences between cells.
The better cell at 3.2V would most likely be the better cell at 2.8V. If there were any changes below 3.2V they would be small since thereâs only a short amount of run time left between 3.2V and 2.8V. It just doesnât matter much.
Just a general side noteâŚ.
If the lower voltage data is important for a particular application I strongly recommend testing the cells under consideration to those lower voltages. I can only provide a bit of general guidance towards which cells you might consider. 
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Yeah I remove the bulk of the butyl tape every time I open up the enclosure. And then apply a bead. I stretch it out before I apply it is only 5 wide & maybe 1,5 mm tall.
I solder in between the cells. With added flux and high quality solder & iron it is a 2-4 second job first to add the solder to the nickel then to join the tinned wire to to the pool of solder. The heat transferred to the cell soldering like this is not a factor tbh. I have confirmed with thermal imaging camera as well. Try it if you donât believe me. The nickel is shit at transferring the heat.
Using two wires between each P-group to distribute the current flow.
The battery box is contoured at the bottom so folding up is not viable. And I would also build in height. As well as increased risks of short. If I rubs against the deck.
Right now I have a air gap of roughly 2mm between the cells and the deck so nothing ever rubs. And the enclosure wonât budge unless you really hit something. And then it is a compression load and there you will dent the can before you wear through the pvc wrapping. And tbh then you have bigger issues as the ground clearance is massive to begin with.
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the fiberglass tape?
Yes. How can I find it, and what is speical about it?
Filament tape. It has fibreglass in it and is very strong.
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I got mine from aliexpress, and itâs just very strong tape. You canât tear it.
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