So right now you have 7 layers of 8mm wide and 1.5mm thick nickel strip?
Yes. You can look at the pictures above to see the exact configuration.
According to the table from es it would be like 7*7a so 49a in total. But iām not sure if you draw 49a for a full discharge cycle. I think the values from es are for constant current. Iām sure 7 layers of 0.15 nickle can handle more current for peaks of 15-60sec.
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That is my thinking too. Looking at my metr logs from my other board the time I spend above 35A is very small usually only 5-10sec.
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Look at the battery builds with cell level fusing. There people use even very thin copper wires for each cell. So this slim wires can handle like 15-20A for peaks without to burn out. If to compair your 7 nickle strips to it I think you donāt need to worry with your 80-100A peaks max.
By the way, would you mind to share with us how you managed to get your motors run cool? If I remember right you had some issues in the beginning that they overheat very fast.
@taz I hope you mean 0.15mm because 1.5mm is really thick.
From what I know 1 nickel strip that is 10mm X 0.15mm should be able to handle 15A and 20A for a really short time. That means 1 nickel strip that is 8mm X 0.15mm should be able to handle 12A? (15A*0.8) 0.8 because 8mm is 80% of 10mm.
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I think I finally solved it today. After many unsuccessful attempts from lowering currents, taking out the v-ring to reduce friction, printing motor fans and reducing gearing the problem was that one of the bullets for each motor was barely inserted.
I only managed to test it for 10-15min but I used some really steep hills that I would normally not try to get up on a board and the motors did not overheat.
@trampa has been really helpful through all this and checking the phase wires was actually his first suggestion.
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sorry guys, typo error.
Yes 0.15mm thick.
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Glad to hear that everything is working.
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Good to hear that it was not fault of the motor and you could solve the issue together with frank!
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The thing is that there is no real information about that. I couldnāt find any real tests or data sheets to it. If somebody has something like this for nickel strips than i would be happy to get it linked. The thing is that the max current a nickel strip can handle also depend on the length of the strip itself. Same like with a silicone awg wire. The constant values for silicon wires are usually give for a specific length. The shorter, the more current they can handle.
If a 10mm 0.15 nickel strip could really just handle 15a for a short time I think companies like nkon wouldnāt sell 35a rated cells with 8x0.15 nickel taps welded on
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if your worried about heat, just add some copper cable on the strip, since you have 7 layers it wont heat up the cell at all while your soldering it, especially if you put solder blobs and let it cool down and then just touch it so the cable sinks in the solder
I have been doing that on my 12s6p packs, I put 5 layers of 10x0.15mm nickel and 2x 2mm2 copper cable per series connection thatās around 50A only from the copper from a chart that I just found online but lets say its more 30A or so just to be safe
Maybe add a temp sensor to one series connection and see the max temperature, IMO this is too much work and if your super paranoid add some more nickel/copper
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Got a schema on my computer. Will post later 
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Damnnn how much Ah is this ? Insane job !
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21Ah 10char
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I was looking a bit more around because of the nickel strips. Here is a test with 12mm 0.15 nickle. The test ramping up to 28a and the strip get up to 51degree after 3min of load
If now to calculate that one of your strips will see max 15a for some secondsā¦ 
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Hello Taz.
I really like your battery build, going to build a 12s7p myself and now looking for components, welder and to learn how to do it according to best practices.
I have a concern regarding the picture with the discharge cables. The discharge cables are soldered on the nickel strip at only one point of the strip.
From what I understand this will make all battery current flow through the last nickle strip and not be divided as between the series connections.
As an example lets say you put max 70A ābattery ampā, then the 70A will be divided between the 3 and 4 cells around the connection point like 30A and 40A depending on how the resistance divide it. In the series connection with 7 strips there would be 70A/7 = 10A each.
Am i wrong with my assumption?
Other than that i think the build is looking great, will copy a lot of your work!
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You are not wrong. If you look closely you will see there is more than one nickel strip on the first and last parallel groups.
Hi, thanks for the quick response.
I did not see that, good job!
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Sick build. Did this come stock or did you make it, or can u order it? This would have saved me so much heartache !
Sorry, the divider. I didnāt see on site. Maybe I am a dumb.
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