Wire size is a little more complicated than that but this thread has a couple ways to approximate the conductor rating of braided copper.
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Finding wire conductivity by comparing weigh seems a lot simpler.
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We already know you like things simple
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I like things more accurate too
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Na, it was a dead short
yeah, thats where ill get cells, they have nickel, not braided copper tho, unless im blind
My new battery build i just started 18s2p with a split pack of 2s2p total 20s (onewheel)
Molicel p42a
i
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What are the disadvantages of making series connections using nickel for underslung esk8 brick packs?
This would end up in a stiff mtb style deck. No flex.
A lot of work layering welded nickel when u could solder copper. Or maybe u could weld a copper/nickel sandwich and some have good results.
The biggest issue i find is that you have to make sure the pack is more stiff. If there is any deflection at all the vibration of riding will slowly degrade and break the connection. Like if you bend the nickel back and forth you can break it from work hardening. The sil wire can be bent and flexed orders of magnitude more times without falling.
Imho you can use nickel series connectors but you must eliminate all the flex. Also how the nickel flexes will impact how quickly it degrades - it only bends in one plane not laterally - the nickel should not be where the pack gets its structural strength. Ymmv
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Ya, what @Pecos said. And thereās simply no way to eliminate all flex in an esk8 pack that is mounted under the board. You will also bw introducing much more resistance to your pack will will lead to less efficient energy utilization, more heat and more voltage sag. On top of that, your battery will be more prone to failure.
What is the reason you are avoiding silicone wire?
Huge pack & lots of soldering. Iāve broken previous solder joints, whereas previous nickel connections have been fine so far
(longitudinal ones that flex with the deck length, not transverse that flex with vibration)
Thatās a good point I forgot, i havenāt been able to make an under slung pack rigid enough except where i used aluminum u chanel and a crap ton of fiberglass boardā¦ and i still had a failure - its actually one of my last frustrations before i found this forum and saw some of the methods here and upgraded my methods.
Even on escooters vibration kills un potted under slung packs - that i have taken apart so like 3-4 so far i think. Though some failures are also due to bms failing - which i suspect is also vibration breaking solder on loose components
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Post up some examples? Maybe there is a problem with the solder method or process the extra eyes here can help tune? Over wicking and too short wire lengths were my personal issues initially- i kept trying to keep the wire very short and direct but that didnāt work out so well for me
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Is there a chart that shows resistances for nickel v stranded awg?
The solder peeled off the nickel due to either a combination of vibrations and/or poor adhesion. The solder joints that failed were not of a different color, so I did not suspect any heat related issues were at play. Nickel was from a US supplier and passed the acid test.
I donāt have images on me - will take them when I get to the board.
Unfortunately we havenāt had anyone do any testing to demonstrate the impact of using nickel vs tinned copper.
A couple of things to get your joints adhering to the nickel better:
- Use lead-based solder. Kester makes a good one. Either 60/40 or 63/37 alloys will work well.
- Scuff the nickel where you are making your joint
I do not do pools of solder in advance as I get much better joints doing each joint fresh. Make sure your solder is in a completely liquid state before removing your iron. Look for shiny, smooth joints.
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I do largely agree with the people above, but I did it recently by printing a big frame for the battery and epoxying the cells in place so the loads are (theoretically) taken by that.
Weāll see if it holds up and itās still a sample size of 1 so I donāt want to oversell it. Itās also a relatively small pack at 16S1P, on a short stiff board with a pretty stiff enclosure, surrounded by padding
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