Adhesive-backed copper tape ampacity

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I got some adhesive backed copper foil off amazon and probably asking way too much of it but would like to connect these to 18650s and do 15amps through it. My bad calipers show the copper and glue are .1mm thick and maybe assuming the copper were only .5mm thick at a 15mm wide strip the copper is conductive enough I think but what’s with a conductive glue?! In a way it sounds ideal getting in all the nooks and it’s very thin and amazingly strong, I’m pretty stunned by the glue. But can it really be conductive enough for high current and sustain cycling of heat. I doubt it.
Can I hook my cheap 10 amp 50v bulk supply up to a strip and work my way down to thinner n thinner strips to see what happens? I have no adjustable power supply.
 
How long is the strip you have? If it's long, you may be able to get a resistance reading out of it with a good multimeter. Measure its length, then measure its resistance. Then calculate ohms/foot and use V = IR and P = I²R to decide whether your voltage drops and heat dissipation are reasonable.

You don't really know anything about the thickness of the copper by measuring the copper plus adhesive. If you clean the adhesive off using a solvent, you may be able to get a good thickness measurement and calculate the copper cross-sectional area. That would be equivalent to a wire gauge.
 
My multimeter is crap. But the goal is to use the adhesive. can you decode this math? https://www.researchgate.net/publication/273248165_Electrically_conductive_acrylic_pressure-sensitive_adhesives_containing_carbon_black

The copper content should be good and conductive enough I think but getting to the copper through the “conductive” adhesive, how much resistance is there and what heat would be formed per amp? The adhesive is good to very high heat at least. Maybe would create very high heat.

I didn’t get the most conductive tape I see after looking at my link but what’s the potential with the best stuff? Or maybe could even add a tiny sprinkle of copper powder at the center of connection point and it could cut through the adhesive maybe.


Maybe my power supply has a non-shorting function because it wouldn’t put any amps through it.


The resistance numbers here show huge. https://www.stockwell.com/data-sheets/3m-xyz-conductive-tape-9713.pdf
 
NO. Resistance will be jacked... It says in the sheet, 500mOh / copper to copper.. and more any other metal. Ive tried this before, with different kinds of taps, and concluded adhesive is no good for amps and sheet doesn't connect easy. I have seen foil thick enough to solder to. When you study copper traces in PCB for handling current , Circular mils / cross section, circulr mils / amp, connection resistance and ect. you see that you want at least a 4 oz. ( trace) copper for the capacity that would be of use to us.

Ive datalogged charges and discharges from 1 foot of multiple layers calculated for the amps.... Ir was 100mOh+ / CONNECTON.. and batteries need lots of connections... repeatable and readable.. It will turn a 1 ohm cell into a 101 ohm cell... think about that... and I thried some 25 layers or more... still the same buildup of resistance...

ONLY good for shielding, protection, grounding, and physical protections, and similar. No good for power transmission IMO.
 
I remember seeing a similar product and the specific product that I saw was intended to be used as speaker-wire. It could be attached to a wall and either painted over or covered by wall paper (or covered by kick-board trim). By being very thin and flat, it would be almost invisible without needing to drill holes in the wall, or running normal wire along the floor.

I have serious doubts that the glue on one side is very conductive. I just did a quick google and I now see that they are advertising themselves as conductive glue so that the installer doesn't need to solder the ends to connect two sections, but simply overlap the ends a few inches.

I understand the appeal if the copper foil is cheap. If you made bus-plates out of it (to accomplish both the series and parallel connections), I would try pressing the bare copper side (no glue) onto the cell, and attaching a strong neo button magnet on the glue side.

The stuff I just googled (specifically with "conductive glue" on one side)...it is advertised as 0.025mm thick. I know that 0.10mm copper crumples like paper, so this stuff is super thin. Since copper has four times the conductivity of nickel, 0.025mm copper would carry the same current as 0.10mm nickel.
 
Conduction is a function of total area of tape making contact to cell.
The best (made by 3M?) does not even come close to working for battery pack applications.
Things that I have used it SUCCESSFULLY for include:
*)RF Shielding
*)Low-power grounding strips between chassis metal parts.
*)Back of Solar cell solder connections to wires (work TONS better than sucky solder-pads on cells!).
*)Low power (milli-amp) NIMH round-cell battery solder connections.
*)High-power pack builds where I use tape REVERSED (metal-side folded over two LIPO pouch-type terminals) clamped together between plates....adhiesive-side of copper is to simply keeps things tighter (not conduction any power).

Issues include:
*) Low current carrying capability
*) Tape comes off over time.....even if it could carry amps it would eventually peel off over time.
*) Quality is function of adhiesive and specs can not be verified unless you have a lab/time.
 
I'm now thinking that this product might actually be useful for making parallel connections in a P-string, but...I wouldn't even bother to experiment using this for series current (even at only 10A peaks per cell)...just my humble opinion...
 
a shame as the thickness at .06mm makes it good for cell to board connections in my case. Ill try welding it. It would be ideal if it welds as the glue is really good and will reduce stress on the welds and the tape is cheap. Thanks for you help!
 
My thinking in solderless no-weld does involve conductive adhesive, usually silver-filled epoxies.

However not relying so much on passing current **through** a layer of it, prefer direct contact of the wire / fitting to the battery terminal

with a constant active strong but flexible (rubber) clamping force holding the contact surfaces tightly together.

Just using the adhesive

A. as a sealant **around the perimeter** of the contact area, against future corrosion

B. to prevent lateral movement of the wire relative both to the battery terminal and the rubber exerting clamping force.
 
I do not think the copper thickness is itself enough to carry the current my design requires.

If a fine-stranded wire is "fanned" directly against the cell terminal surface, I think such a "dot" could be used to hold it in place.

But I would not rely on that adhesive alone to do so in a high vibration/ shock use case.
 
cross-reference https://endless-sphere.com/forums/viewtopic.php?f=14&t=99213

a different example material from 3M

https://www.3m.com/3M/en_US/company-us/all-3m-products/~/3M-Electrically-Conductive-Cushioning-Gasket-Tape-ECG7073H/?N=5002385+3294001372
 
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