idk I am going to have a 2P made of these then i would like to try charging at 10A I guess.
Still less than 1C haha
15C charge rated somehow
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Hahaha, thatās pretty sweet still!
It would depend on the size needed but I may be capable of getting Aluminum laser cut. LMK What size would be ideal and ill look into it.
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bus bar availability/cost is what holds me back from jumping in
Yeah tricky thing about these cells is the mixed anode and cathode materials. Definitely want them sealed up well to limit creating high galvanic corrosion potential. I have a ton of these cells from before I was even interested in esk8, and havenāt ended up building any huge packs for these so mostly have been just clamping them with stainless bar stock (to avoid the GC concern), but always meant to make tin plated copper bus bars.
Problem with that is buying tin plated bus bar stock is expensive from what Iāve seen, although they can be DIY chemically plated reasonably easy, and very cheap if you donāt mind a little home-chemistry of only moderate danger. 
What kind of guide would you guys want/need for making bus bars? I mean non-plated copper ones would be about as simple as can be, Iām not sure why theyād need a guide, but if you guys want something more in-depth for something like tin plated ones, I could probably make something happen.
I gotta be honest, and to be clear this is just my āgut reactionā but I personally wouldnāt trust the crimps for a pack being used in our types of applications, where lots of potential vibration and shock stresses are a factor, unless the packs were potted heavily (hot glued to hell and back at the junctions where those crimps are), but maybe Iām not giving them the credit they deserve. Shorting any reasonable voltage of these cells though, creates a pretty instant and powerful arc-furnace, thatāll blow a hole in basically anything. I mean, one of the killer apps of these cells is making DIY arc-welders or smelting furnaces, so keep that in mind! Iām no safety Sally, be crazy and have fun, just be aware of the potential power. 
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What are the cathode/anode materials? I was guessing they were both aluminum or something.
As far as bus bars, my idea would have been aluminum stock and bolts
https://endless-sphere.com/forums/viewtopic.php?f=14&t=104415
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With these cells remember that they need to be kept together fairly tightly. This helps them stay stable during high discharge scenarios. I remember watching a video where having them compressed together allowed longer continuous discharge at the full 200A. Obviously heat doesnāt work in our favour here, and they sag. Their high charging rate is due to the fact that they have come out of electric buses, where thereās possibilities for a couple hundred amps available for charging. Porscheās 350kw chademo DCFC is one example of this.
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Doesnāt this contradict itself though, youād want space between them for heat dissipation but also want them compressed to run more amps through them? Iām not sure I follow
If you are running these hot enough that having any space for dissipation makes a difference, then you should lower your discharge. You want to minimise any chance of puffing up, as any puffing will make them less stable, even at the same discharge levels as pre-puffing
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Sandwich them w/ thermal material or watercooling like in a Tersla.
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I still have 4 left.
We could do a thunder dome (a lightening dome)
SPIM VS A123,
@iamasalmon hold my fire extinguisher
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Ah okay gotcha. I wonāt be expecting those kinds of amp draw, but I was wondering.
Copy that.
Iāll make sure the camera is rolling 
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So according to this chart:
Which I could very much be reading incorrectly so please feel free to let me know if thatās the case. But ideally here we could use something like this.
80mm x 10mm x 3mm
No real idea on how much the thickness is taken into account on this chart so my main focus is the Area - which any way you slice it with the current sizing is well beyond 200mm SQ - which should be good for around 360 amps.
That said, I know for a fact I can order a sheet of 1/8th" aluminum from my local fab shop and I also know that they can cut it down using the Lasers. I suspect that the Laser time is going to cost the most due to the sheer number of these things that you can get out of a single sheet.
Nested with some space between cuts ideally we could see something like 3k of these from one sheet. That alone - is going to be pricey due to the amount of geometry needed to cut these things.
180mm of travel per piece * 3000 = 540,000mm of cut length not including the holes cut for the bolts.
Back when I worked at this shop, my aluminum parameters if I can recall correctly were something around 4500mm per minute on 0.120". Which puts us at a little over 2 hours of cut time not counting pierce, and head travel or holes.
So, this all said I can get a quote from some of the guys I know at this shop and see where we land, but if the laser time is still what it used to be these will likely not be ācheapā by any stretch of the imagination, ideally id have liked to see these around $1 each, but if my math is accurate for the pricing probably closer to 4.76 each.
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I believe that the area column in the chart is the cross sectional area, not surface area.
So the thickness would depend on the width of the bar. 12mm x 2mm bar has an āareaā of 24mm^2
Also in this chart, current carrying capacity is not defined, so itās difficult to equate that metric to the length of the bus bar in a particular application. There is an inverse relationship between distance current travels and how many amps the conductor can carry.
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by my math (pls double check itās late) twelve 80x10x3 aly bus bars at 200 amps is under a half watt of heat output
but how do you build a pack with bars and bolts and nuts? would you need lots of space between the cells for the bolt heads and the nut sticking out the other side?
edit: math
resistance = resistivity x length / cross sectional area
resistivity of aluminum = 2.6548e-8 ohmā¢meter
in this example, area is 8e-3 m x 1e-3 m = 8e-6 mm^2
length is 3e-4. resistance of bus bar is close enough (stoner math) to 1e-6 ohm
joule sez power = current squared x resistance, so for 200 amps itās 4e4 x 1e-6 and we have twelve of them thatās 4.8e-1 watts
high school was a long time ago, bear411 with me
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pop rivets
I have some fat copper bar at home I might start messing around with.
You guys got my interest
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not quite what you are talking about but I came up with an idea for making thin flat packs using these cells and the foil crimps or bolts.
Overlap them then connect some tabs and isolate others.
it has a couple of issues, the top 4 cells would need to be connected with wires and that the tabs could short at the series connections if not protected.
let me know what you think.
Someone in EU has 10 of these to share with me?
Maybe. Think I have 52. Customs raped me tho, so wont be the listed price on batteryhookup
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