How do I create a dummy cell for testing noncylindrical cells?

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JoeRodge
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How do I create a dummy cell for testing noncylindrical cells?

This might be a stupid question but I’m not very creative. I want to test non-cylindrical in my SkyRC MC3000. I’ve seen it discussed on CPF but none really seemed quite I and easy and I’m not sure how safe different methods are. Anyone have any resources?

Edited by: JoeRodge on 03/17/2019 - 04:26
YuvalS
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wooden/plastic cylinder roughly same dimensions as 18650 and 2 wires screwed to the ends (one to each end), can use some solder to improve conductivity. 

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JoeRodge
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What do you mean by screwing the wire to the wood? As in run the wire under a screw and then tighten it? Is there a formula or an easy way to find out how much this would increase internal resistance readings?

Would a longer wire alter capacity readings?

YuvalS
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JoeRodge wrote:
What do you mean by screwing the wire to the wood? As in run the wire under a screw and then tighten it?

Yes, you can also use some ring terminals like this but I don't think it is needed.


JoeRodge wrote:
Is there a formula or an easy way to find out how much this would increase internal resistance readings? Would a longer wire alter capacity readings?

Of course the wires have some influence on the readings but I think that if you use good wires it can be neglect.
I an not so good in electronics so I cannot give you a formula, but you can easily do some experiments: measure internal resistance and capacity of a good 18650 cell inside the charger and then repeat these measurements on the same battery using the dummy cell with long and with short wires and see if there is any difference.    

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