I would avoid plated steel. Too much resistance means lots of loss in heat and big voltage sag. The steel could turn red hot and melt at too high currents.
We have an example of the possible complications here :
https://endless-sphere.com/forums/viewt ... 0#p1234386
For pure Nickel strips see my post here :
https://endless-sphere.com/forums/viewt ... 5#p1214787
But in summary
Let's say your strips are 10 mm width by 0.2 mm thickness
It means your strips have a
cross sectionnal area of 0.000002 m2
Now let's say you want to use 10 cm long strips... you can calculate the resistance of each strip...
Now let's compare it for different metals, using resistivity tables from here :
https://en.wikipedia.org/wiki/Electrica ... nductivity
1. COPPER STRIPS (10mm width x 0.2mm thick x 10 cm lenght)
Resitivity of Copper is 1.68 x 10^-8 Ohm.m
So the resistance of a 10 cm lenght is : [1.68×10−8 Ohms.m] x [0.1m] / [0.000002 m2] = 0.00088 Ohms or
0.88 milliOhms
Since dP (heat loss) = R x I^2,
At 5 amps, 0.02 W of heat will be generated by just one 10 cm strip.
At 10 amps, 0.09 W of heat will be generated by just one 10 cm strip.
At 20 amps, 0.35 W of heat will be generated by just one 10 cm strip.
At 30 amps, 0.79 W of heat will be generated by just one 10 cm strip.
At 40 amps, 1.41 W of heat will be generated by just one 10 cm strip.
At 50 amps, 2.20 W of heat will be generated by just one 10 cm strip.
At 100 amps, 8.80 W of heat will be generated by just one 10 cm strip.
If I assume that a 1W CONSTANT heat loss PER STRIP is the max loss I can tolerate, I could go for up to 33.7 amps (SUSTAINED) with Copper of those dimension specs.
If I assume that a 5W PEAK heat loss PER STRIP is the max I can tolarate, I could go for up to 75.4 amps (PEAK) with Copper of those dimension specs.
2.
NICKEL STRIPS (10mm width x 0.2mm thick x 10 cm lenght)
Resitivity of Nickel is 6.99 x 10^-8 Ohm.m
So the resistance of a 10 cm lenght is : [6.99×10−8 Ohms.m] x [0.1m] / [0.000002 m2] = 0.00349 Ohms or
3.49 milliOhms
-->
4 times more resistance than pure copper =
4 times more heat power loss than with copper (dP = R x I^2)
Since dP (heat loss) = R x I^2,
At 5 amps, 0.09 W of heat will be generated by just one 10 cm strip.
At 10 amps, 0.35 W of heat will be generated by just one 10 cm strip.
At 20 amps, 1.40 W of heat will be generated by just one 10 cm strip.
At 30 amps, 3.14 W of heat will be generated by just one 10 cm strip.
At 40 amps, 5.58 W of heat will be generated by just one 10 cm strip.
At 50 amps, 8.72 W of heat will be generated by just one 10 cm strip.
At 100 amps, 34.9 W of heat will be generated by just one 10 cm strip.
If I assume that a 1W CONSTANT heat loss PER STRIP is the max loss I can tolerate, I could go for up to 16.9 amps (SUSTAINED) with Nickel of those dimension specs.
If I assume that a 5W PEAK heat loss PER STRIP is the max I can tolarate, I could go for up to 37.8 amps (PEAK) with Nickel of those dimension specs (0.2 mm thick, 10 mm wide !)
3. CARBON-STEEL STRIPS (10mm width x 0.2mm thick x 10 cm lenght)
Resitivity of Carbon-Steel is 1.43 x 10^-7 Ohm.m
So the resistance of a 10 cm lenght is : [1.43×10−7 Ohms.m] x [0.1m] / [0.000002 m2] = 0.00715 Ohms or
7.15 milliOhms
-->
8 times more resistance than pure copper =
8 times more heat power loss than with copper (dP = R x I^2)
Since dP (heat loss) = R x I^2,
At 5 amps, 0.18 W of heat will be generated by just one 10 cm strip.
At 10 amps, 0.72 W of heat will be generated by just one 10 cm strip.
At 20 amps, 2.86 W of heat will be generated by just one 10 cm strip.
At 30 amps, 6.43 W of heat will be generated by just one 10 cm strip.
At 40 amps, 11.4 W of heat will be generated by just one 10 cm strip.
At 50 amps, 17.9 W of heat will be generated by just one 10 cm strip.
At 100 amps, 71.5 W of heat will be generated by just one 10 cm strip.
If I assume that a 1W CONSTANT heat loss PER STRIP is the max loss I can tolerate, I could go for up to 11.8 amps (SUSTAINED) with Carbon-Steel of those dimension specs.
If I assume that a 5W PEAK heat loss PER STRIP is the max I can tolarate, I could go for up to 26.4 amps (PEAK) with Carbon-Steel of those dimension specs.
4 . STAINLESS-STEEL STRIPS (10mm width x 0.2mm thick x 10 cm lenght)
Resitivity of Stainless-Steel is 6.90 x 10^-7 Ohm.m
So the resistance of a 10 cm lenght is : [6.90×10−7 Ohms.m] x [0.1m] / [0.000002 m2] = 0.0345 Ohms or
34.5 milliOhms
Since dP (heat loss) = R x I^2,
At 5 amps, 0.86 W of heat will be generated by just one 10 cm strip.
At 10 amps, 3.45 W of heat will be generated by just one 10 cm strip.
At 20 amps, 13.8 W of heat will be generated by just one 10 cm strip.
At 30 amps, 31.1 W of heat will be generated by just one 10 cm strip.
At 40 amps, 55.2 W of heat will be generated by just one 10 cm strip.
At 50 amps, 86.2 W of heat will be generated by just one 10 cm strip.
At 100 amps, 345 W of heat will be generated by just one 10 cm strip (IT WILL MELT FOR SURE !!!)
If I assume that a 1W CONSTANT heat loss PER STRIP is the max loss I can tolerate, I could go for up to 5.4 amps (SUSTAINED) with Stainless-Steel of those dimension specs.
If I assume that a 10W PEAK heat loss PER STRIP is the max I can tolarate, I could go for up to 17.0 amps (PEAK) with Stainless-Steel of those dimension specs.
So of course, nickel plated steel in not the same as bare steel.... You could make calculation accounting for the plating thickness to calculate the nickel cross sectionnal area to add to the steel core surface area.... But keep in mind plating is usually very very thin, somewhere between 5 and 50 microns of thickness... So the nickel plating is kind of non significant...
I would definitly avoid nickel plated steel.
Heck I'm even trying to stay away from bare nickel.
I'd rather go for nickel plated copper. See my post here :
https://endless-sphere.com/forums/viewt ... 5#p1235640
Why ? Copper is a great conductor... But over time it oxidizes.... So resistance increase in contact points. Solution ?
Nickel really does not oxidises that much, but is a bit less conductive..
So Nickel-plated Copper core is the best of both worlds in my opinion.
Just my two-cents