I don’t see any using lifepo4 or potting or using 50milliamp balancers. Do u?
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i also haven’t seen boosted use superglue on their batteries,
nor any manufacturer ever of any battery type
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You better have an open window nearby, to toss that thing out. I don’t know the blast radius though.
Those perpendicularly-oriented loops boost the current buildup and things will get dangerous quickly! 
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the lack of dicks in the picture is especially dangerous and a big red flag!
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Solder your balance wires to little nickel tabs, then spot weld those to the pack.
Boom, done. No extra heat for the pack, no wack-ass super glue, just good old reliable metal-to-metal all the way.
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Hi folks, sourcing nickel for my next build and wanted some feedback.
I’m planning on triple stacking M50LTs in a staggered pattern to form an 11p group.
The challenge is finding any reputable nickel strips wide enough (~65mm) to overlap all the cells and fold over the top with enough real estate to solder wires to.
Instead of using one beefy strip, would 45mm and 27mm strips be good enough for esk8 standards? Should I overlap the strips (only soldering spot welding the strips together, not to the cell)?
My only concern might be balancing if the nickel doesn’t overlap, but the currents are super low for that so not a real issue.
Sketch below for illustration.
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I ship 200mm wide nickel from the UK if thats something you’d want… lets you effectively cut any shape you want
This might be it.
@Anubis, one question though, if I were to order 5 pieces, would it come as a single continuos 1m strip or 5x20cm?
Hi, am making a 20S-4P battery wired to an existing 20S-8P. am using 21700 samsung 50E witch can put out around 10amps continuous. what type of wire guauge do you recommend I dont really know how to calculate. My esc can pull 100Amps for each motor.
Motor amps and battery amps are different things. A 20s4p 50E can only do about 40 amps out (20 per motor),
edit: i see youre plugging it into another pack, missed that
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in terms of gauge wire to connect the different series groupe what would work best ? I was thinking of 10 guauge wire.
Just to be clear, in total your pack will be 20s12p? And all of it is going to be 50Es? How is the current 20s8p done? Also how old is the current 20s8p pack? If they are fairly heavily used your pack is probably going to pull more current per cell from the new cells than the old because of increased IR. How will you be connecting the new p-groups to the old p-groups? Usually using multiple smaller wires is recommended. Since 4p 50Es should only be pushed to ~40 A you can probably get away with 2x16 gauge. A single 14 or 12 gauge is also enough to carry 40 A though. You really need to think this all through carefully though and it would be very good to figure out what is going on with the original pack first. You may end up not being able to really pull any more current safely even with the added p-groups because you don’t know how much is being pulled from the new cells vs the old ones.
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10awg is overkill. 2x 14awg connections should be more than enough for the 40 amps you should be pulling through that pack at most, and 12awg going to the xt90.
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I took that in concideration, I would say around 30 cycles on my 20S-8P soo its not that bad, I dont really need more power its just for the range. won’t be asking much from that a 20S 12P since its soo massive. and yes they will all be samsung 50E’s.
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Anyone familiar with Daly bms with the temp sensor? Built a 12s3p, all bms pins add up sequentially, voltage from the discharge reads correctly, but I don’t get a usable or even stable voltage reading from the charge port… I’ve always been able to read voltage from the charge port, but I’ve checked everything and battery builder friend has also looked and we can’t figure it out other than this style of bms with the sensor is causing the problem…
Is there a specific reason that you need to get the overall voltage from the charge port? In my experience getting voltage from the port can be a bit dangerous.
My only thought would be that the bms blocks discharge through it in order to make sure that it is wired for charge only.
Also I see that you are using a 13s bms on a 12s battery. Did you take the proper steps to ensure that this would charge right?
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I have a battery meter that I plug into different boards’ charge ports over the winter to more easily/quickly check voltage. And, I joined the 12th and 13th balance leads near the bms plug and connected the one lead to the 12th group/main positive. We even checked it with thermal camera after connecting it all to a 2.5a charger and nothing was getting hot.
https://imgur.com/a/kGpvqiA
