Flat 12S2P battery layout and bms connection

Hey guys, so while I was making my new battery, a couple of questions were raised up.

  1. If I’m using 0.2 nickel strips to connect the groups - would that be enough, or should I use 10 AWG wire instead and just solder it on the top? (See the photo below)

In addition to that, I’m planning to divide the battery into two parts (6s +6s =12s) and connect these two parts using 10 -12 AWG wire. (I’m dividing it in order to fit it in the enclosure that I will make using my vacuum former)

So, the final battery layout (without bms wires would look something like that:

  1. I’m very confused in terms of the connection of my BMS since the BMS has a separate charging port, and I’m planning to do a BMS bypass and leave it only for battery balancing and charging. (example of my BMS below)

After a bit of consulting and googling, I guess I have to follow this schematic (below) and connect the wires (that will go to the ESC) straight to the battery. But I’m ABSOLUTELY not sure about that and need help!

So if there is anyone who had experience with building their battery/working with separate port bms/ knows ANYTHING about it - can you please help me out?)

Thank you in advance! :grinning_face_with_smiling_eyes:

(P.S - Sorry for tagging you in @LeonCamero ! It’s just you helped me out on the matter of bms and charger before, so I thought you maybe know what to do about these issues? :sweat_smile: :pleading_face:)

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Sorry, I had a retard respond to me stupidly that I didn’t get this. I would recommend to always weld your packs and not solder them until you have your 6s2p set up to make it into a series of 12s. Now I’m not sure on this myself but .2mm nickel strip should be enough for your battery build since many people uses those in their builds with copper (higher amps)

When you’re soldering, you are soldering on the nickel strip itself, so make sure you have a small tab for that, especially for the bms wires itself (tabs on the positive sides of the battery). You don’t need a tab for the 10awg since that will go on the nickel of the battery weld. You can also solder the 10awg on it to make a flexible pack, but make sure it’s in series. For the bms wires, you’re basically doing one negative on the negative side of the battery, which are usually the B- or a black b- wire. It can also be your start of the negative discharge point. But all your other wires must go accordingly by voltage and on the positive side of the battery. Ignore P-. It’s useless if you’re bypassing.

You can then connect it on the bms with no issues.

Other than this, I’m very limited in what I know. So someone else could chime in.

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What is the width of the nickel strip? they can be .5 .8 1.0 mm here is an ampacity list:

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I’ve seen others use .2mm pure nickel strips. Use those if you’re making batteries.

Here’s the chart:

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You can also use the american AWG copper wire gauge chart from wiki. Nickel is 22% as conductive, so use the cross section of your nickel strip (l*w) in mm2 and compared the AWG and multiply by 0.23 to have nickel equivalent temperature ranges.

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How about you go get some bitches …