Thanks for sharing that. Impeccable work and nicely put together.
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Thanks guys for the kind works 
@ducktaperules will have it, by Late next week should have a few kits available.
@esk8manbabes was up early, so went for it.
Spot weld is way faster than soldering 
.
@moon thanks for the pictures.
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Whats the idea behind having solid nickel strip the first and last 3P group but inbetween of the pack the nickel is cut out to thinner connections?
I guess it’s meant to work like cell level fusing, but why than no cut out on the plus and minus terminal of the first and last p-group?
If it’s no secret, is that 0.15 or 0.2 nickel you use?
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Does anyone see any concern for lack of fish paper between P groups, the bottom of the pack and the aluminum enclosure, and some of the thin nickel?
This looks way better than anything I’ve made, so i’m just curious… and regardless this is all super sexy and super clean!
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Plenty of Kapton and siliconed down, so won’t be rubbing up against anything.
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if configure the way you suggest the main negative and positive will end up being side by side at the center and a potential soldering mistake will be BAD, better this way and assembly efficiency is increase.
Nickel 0.20
@Skatardude10
The fish paper is optional since there is a gap between the top of the cell positive contact and the negative body of the cell, by having proper alignment this is not a problem.
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I think my English is not good enough to express what I mean 
Basically why the nickel in red marked are solid and the blue marked nickel has special cut out?
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I don’t think it’s too thin. Don’t forget that’s only a 3p pack and that’s not going to be used as single 3p pack. If you run 3-4x of this packs parallel the current will also be shared between the packs.
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that is to improve efficiency in the assembly process.
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me: Thats a cute little PCB…
OMG THATS MASSIVE!
Great work Ernesto! Looks really professionally made and designed
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Thank you for making such an awesome modular design and for the write-up!
Apart from this concern:
I have a wish that would make this far more valuable for the DIY crowd:
If you designed your current carriers (and maybe the BMS) for 20-30A per cell, it would make it possible to use a 12s3p or 12s6p with sufficient power. I think there is a good reason that Samsung 40T is currently the most favored cell - people like to have power but don’t need or have the funds for a 12p pack.
If you just upgraded the nickel plates to solid ones (as suggested) use 10AWG wire, and bypass the BMS for discharge, this wish would already be addressed.
Great work, keep it up!
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What’s wrong with a 12S6P pack of Sanyo NCR20700B? That’s 120A DC output right there.
I love the idea of cell level fusing. @Kaly probably wants battery pack kits as safe as possible.
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20700b is only 15a continuous
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Not according to BatteryBro! 
90A DC is still plenty Amp for most.
Hey @Kaly, do the 20700 kits have wiggle room for 21700 cells or no?
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Assuming the cells are true 20A cells, using his kit, you could still only get 10A per cell out of it, for a total of 60A.
That is because his current carriers and BMS are designed for 30A total per 12s3p module.
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So you can’t bypass BMS discharge because the Nickel is too thin?
You can’t bypass it safely.
To me, the nickel looks like it will support 10A per bridge at most.
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that shyyt is Pluto man…bruh you way out there.
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So if I want to bypass the BMS, just upgrade the Nickel?