Why not use copper clad steel spring for compression battery?

[Hummina Shadeeba]

https://mwswire.com/copper-clad-steel-wire/

Steel being probably the most reliable compressor and copper around it seems an all-in-one solution. Could replace the springs and wires on something like this. Makes me wonder why they don’t do that already.

I called MWS and of course they say will be no problem. It’s not spring steel and not much copper on these but still

 

[SniperGaulois]

What amount of copper would you put on the steel? In microns?

 

[Hummina Shadeeba]

Microns aren’t going to be enough if u expect to put out any real current. The link shows 10%. The more copper the better if the cladding doesn’t come off and the spring continues to act as a steel spring without fatigue.

 

[SniperGaulois]

Oh that's interesting! I didn't know about that. I think it's used for very high tensile strength wires, perhaps to go long distances between phone lines, it's used for telecoms and for grounding.

This page says: Copper Clad Steel is ... containing a low carbon steel. https://fiskalloy.com/product/copper-clad-steel-40/

spring steels have medium to high carbon content of 0.5 to 1.0 percent. https://www.google.com/search?q=spring+steel+carbon+percent

for very high performance, there are many copper beryllium wires and springs available, they have conductivity perhaps 3-4 times higher than CCS and fatigue mtbf is 10,000 to 10,000,000 + cycles. https://www.springworksutah.com/materials/round-wire/copper-base-wire/beryllium-copper

The carbon content of CCS is flexible, so you can perhaps find some medium-high Carbon CCS, it's still only 3-5% copper versus Be alloys which are 95+%

 

[Hummina Shadeeba]

The percentage of copper in the alloy doesn’t reveal the conductivity but as u say it’s not spring steel and I wonder how mild steel fare as a spring. My link isn’t an ideal example but shows a possibility

as u show beryllium copper can be a spring and has a high fatigue limit with similar conductivity. Sounds good or maybe better and haven’t looked into it.

 

[spinningmagnets]

The style of cell holder shown above also has a variation with a leaf-spring instead of a coil-spring.

The Leaf-spring makes it easy to slip a 0.10mm thick copper sheet between the cell and spring, for using higher currents.

For environments that are corrosive, Keith at "18650 heat shrink and cell holders" carries nickel-plated copper strips.

 

[spinningmagnets]

The style of cell holder shown above also has a variation with a leaf-spring instead of a coil-spring.

The Leaf-spring makes it easy to slip a 0.10mm thick copper sheet between the cell and spring, for using higher currents.

For environments that are corrosive, Keith at "18650 heat shrink and cell holders" carries nickel-plated copper strips.

Just an option.

Nothing wrong with copper-plating coil-springs. Should be easy to find a youtube of how to DIY...

 

[Hummina Shadeeba]

A heavily copper-clad leaf spring on a sled sounds ideal. Could add a strip like you say but clad for the win!