Silver windings!!

[Hummina Shadeeba]

http://www.diyelectriccar.com/forums/showthread.php/silver-wire-better-choice-wind-coilsi-23806p2.html#/forumsite/20977/topics/23806?page=4


Sounds great. Have to figure the costs but seems worth it. It doesn't lose its value in the motor anyway. Add some enamel and burn it off when u need to melt it down to pay rent later. An investment

 

[liveforphysics]

There is substantially more to he had from square copper windings than round silver windings.

Square silver windings or square flat bus bar windings are king until carbon-carbon materials become most cost effective to mfg.

I ordered a dozen ounces of square enamel silver wire from a German supplier around 7-8 years ago. I used about half of it up trying to get a single tooth wound without isolation faults from damaging the delicate corners of the square enameled edges, then gave the rest away to a friend who also had no luck winding with it.

 

[crytex]

The idea of using silver windings is great, and considering hummina's hubmotor's quality standards, it would be a good fit, but I see one big issue being corrosion of the windings, especially at connection or friction points, which could end up shortening the motor's lifespan. however, it would be very interesting to know how much more expensive the motors would get in the end, taking into account efficiency and all.
I for one really like the idea of designing the lamborghini of electric motors, and I would like to see how far this concept can be pushed.
Also, I would suggest only using silver in the windings, and having one of these "bendy" copper cables (as in enertions R-spec motors) actually making the bridge between the motor and the esc, in order to increase the lifespan of the final product and keep the cost down, and eliminating the need to shrinkwrap the **** out of the wires to a certain degree. Also it's a bit fancier.

Also, the current silver price is 16.23usd/oz or 522usd/kg.
copper density is 8.96 g/cm3 and silver density is 10.49g/cm3.
now if we were to strip a stator of it's windings, and weighed them, we could find out what the bare minimum price could be.
x being the weight of the stripped windings in grams, this bare minimum of a price in usd would be:
x*(10.49/8.96)*0.522$
or in easier terms,
x*0.61$
Now this is a vague guess, because of wire coating, silver wire prices, manufacturability etc, but it's a start and I would like to see how this would affect the price of making hummina's hubmotors.

 

[Cowardlyduck]

There is substantially more to he had from square copper windings than round silver windings.

Square silver windings or square flat bus bar windings are king until carbon-carbon materials become most cost effective to mfg.

I ordered a dozen ounces of square enamel silver wire from a German supplier around 7-8 years ago. I used about half of it up trying to get a single tooth wound without isolation faults from damaging the delicate corners of the square enameled edges, then gave the rest away to a friend who also had no luck winding with it.

That's interesting.
I wonder if you would have had more luck if it were heated first?
Obviously that would come with it's own difficulties, but might make it more possible.

Cheers

 

[Hummina Shadeeba]

From the thread I linked I read silver has better electrical and thermal conductivity and seems the best thing out there in the present world. Silver square wire being better I guess

How did you insulate the wire you used Luke or did it come done? Maybe a better or thicker coating and more patience would work

I wanted to do this for just myself and finally wind a motor successfully, a badass motor. Every time I wind I short.
I don't think I'll bother asking the hub motor manufacturer a price to do this as I bet it'd be hours back and forth even if they even would do it and think it would be fun to do myself..if I don't short it non-stop. It'd give me a reason to try to burn out the copper.

The hub motors in all steel are happening if you're interested and should be here in under a month. 1020 steel and high heat rubber to go with the N45sh magnets. If only there were a good thermally conductive rubber it could...lay down some heat!

I'll weigh the windings and figure the cost

I don't think corrosion would be a problem if the insulation is right. The connections it would defiantly be worth making
stout. If it did burn up or short the silver value would still be there. Non-disposable. Cook all the insulation off, make an ingot, and resell it or maybe find someone who could turn it back to wire

 

[liveforphysics]

Corrosion is less of an issue with silver than copper. If you get the stuff made for motors it comes insulated with 220c-240c enamel.

The trouble is, it's far better to be square copper than round silver, yet none of the square windings are friendly towards winding without chaffing off the enamel.

I wouldn't even bother to attempt a square winding again until I had utterly mastered round wire motor winding, and even then it's rarely done by humans for much of anything beyond tiny RC slot car motors.

 

[speedmd]

Silver has some serious down sides with regards to work hardening and migration. Work hardening from a few repeated sharp bends will make it no better and potentially worse than copper in conductivity. Copper also work hardens but not easily. Silver also will migrate some distance with anything more than a few dozen volts running through it in moist environments. Not so bad in dry conditions. It needs to be fully softened to get significantly better than copper.

 

[Hummina Shadeeba]

annealing happens at 1200f with silver. bummer. so the hardening from working (literally bending) will reduce the silver's conductivity and it will likely not be any more conductive than copper and that's the final say? copper anneals at a bit lower temp and ive read that it's not worth annealing for use in a motor as it only adds marginal conductivity so maybe the working of silver similarly only slightly decreases it's conductivity. YOu have any links to end the question one way or the other?

how hot can the steel stator get? I imagine the insulation between laminations will breakdown but I cant find a temp. doubt it would get as high as an annealing temp though.

 

[999zip999]

To soften silver wire I wind it in a coil place in a oven to 1,000,-1,300 Fahrenheit, then I drop in a pickle or water will do. This would crack the enamel. It would deep soft. Bending or hammering or rubbing a hard tool on it will work harden it. You can also drop it on a steel table and hear it bounce high twang or thud. Thud is soft. I use it in jewelry but is soft for holding stones in prongs. You would not set a diamond in silver prong setting. Or anything of value is set in Platinum. It an old jewelry saying. It's very soft. Plus the silver solder used at radio shack is for electric 60/40 and is to grey and to soft to solder jewelry. Silver solder is 75% to 90% or soft, med and hard silver solder.

 

[Hummina Shadeeba]

this place:
http://www.elektrisola-usa.com/

sells it already enameled. waiting to see what they write back.

I imagine it comes "soft". How much hardening will my winding it cause do you think? probably use 22 awg. think that's the size. very pliable with the fingers.


doesn't look good:


Cold working of silver considerably increases resistivity: 5% for 90% reduction. Annealing commercially pure silver successively in air and hydrogen disrupts grain boundaries and increases resistance. Tension reduces resistivity slightly as does hydrostatic pressure: 12,000 kg/cm2 causes 4% reduction

for copper:
The maximum conductivity of 29.7% IACS was attained after aging the as-cast material at the temperature of 500 °C for 4 h


but I've seen results ofresistance decreasing in copper annealed as low as 400 to 600f

 

[macribs]

Man you guys. Really looking for the edge. I saw a video a while back of a small RC motor with silver windings, or so they claimed. I just figured they silver plated the copper. Guess I was wrong. Seems you will have to pay premium for that little extra advantage. Are you sure there are not other parts of your build you could put less money into then the silver wire and still get your moneys worth? Could you maybe find a super high tech bearing that will let your motor turn " effortless and endlessly" like those inline skate wheels? Or higher discharge batteries?

But hey, if you take this route make sure you document the hole process and show us before and after power output. If you end up with more power and less heat you still got your savings in the windings. :lol: :lol: Guess you can always recycle 8)

Me I will wait for some ultra tech nano carbon super spun windings to become mainstream. Or maybe I settle for higher capacity and higher performing cells, what is next after Q30? Or will Tesla make a new de facto standard when they start using their new giga factory and new form factor?

 

[Chalo]

Silver solder is 75% to 90% or soft, med and hard silver solder.

That's easy/medium/hard, which correspond to flow temperature, not physical hardness. Silver solders generally get softer as they get "harder" (higher in silver content and melting point). They are available down to 15% silver, depending on what material is being soldered.

 

[Hummina Shadeeba]

They might have used silver coated copper in that rc motor. They do that too. There's one on Hobbyking supposedly but it doesn't even look silver! I'll try the silver after I burn out the copper someday. It would be the ultimate and I'd like to see but am in no rush since the motor will be wound with copper already. (I bet I'll have ceramic bearings by then too) As far as a test of performance I'd just do another run up my local hill or out to the beach and back at full speed and see what temp I hit. I'm not into jewelry and never wear it but those silver windings with the light blue enamel are hot.

 

[Ratking]

If square wires gives the best fill factor and silver is a few percent better conductor than copper, maybe this square silver wire would be good

http://www.wires.co.uk/acatalog/square_jewellery_wires.html

 

[nutnspecial]

Nanotube http://www.nanowerk.com/nanotechnology-news/newsid=37601.php

Silver http://www.diyelectriccar.com/forums/showthread.php?s=dd5ed40f3c0777a268e72cfd9da60ef1&t=23806&page=4
. . . . https://endless-sphere.com/forums/viewtopic.php?f=28&t=13544

Coreless http://www.designworldonline.com/ironless-dc-motors-deserve-a-second-look/

But what about gold windings. . . . ?

 

[liveforphysics]

Nanotube http://www.nanowerk.com/nanotechnology-news/newsid=37601.php

Silver http://www.diyelectriccar.com/forums/showthread.php?s=dd5ed40f3c0777a268e72cfd9da60ef1&t=23806&page=4
. . . . https://endless-sphere.com/forums/viewtopic.php?f=28&t=13544

Coreless http://www.designworldonline.com/ironless-dc-motors-deserve-a-second-look/

But what about gold windings. . . . ?

Gold is meaningfully worse than copper.

Silver with even 0.1% impurity is worse than pure copper.

Square wire in theory is fantastic, in practice getting a single successfully wound tooth was beyond my skills.

The recent generation of carbon-carbon materials make copper and silver both look bad, but at the moment cost many orders of magnitude more.

 

[Ratking]

Nanotube http://www.nanowerk.com/nanotechnology-news/newsid=37601.php

Silver http://www.diyelectriccar.com/forums/showthread.php?s=dd5ed40f3c0777a268e72cfd9da60ef1&t=23806&page=4
. . . . https://endless-sphere.com/forums/viewtopic.php?f=28&t=13544

Coreless http://www.designworldonline.com/ironless-dc-motors-deserve-a-second-look/

But what about gold windings. . . . ?

Gold is meaningfully worse than copper.

Silver with even 0.1% impurity is worse than pure copper.

Square wire in theory is fantastic, in practice getting a single successfully wound tooth was beyond my skills.

The recent generation of carbon-carbon materials make copper and silver both look bad, but at the moment cost many orders of magnitude more.

I re-read some old treads from DIY electric car forum where major and others calculated the gain in decreased resistance from silver, and the 6% decrease in heat reduction is just a part of the overall motor efficiency, did not make any sense to go for silver in my opinion The total gain was more or less 0.1%. But square wire looks interesting. Do you have any examples of mass production or special motors using square wire with success?

 

[Hummina Shadeeba]

Ok silver isn't magic but carbon nano structures are. After spending the morning watching videos on how to make graphene sheets at home I think I'll try to add a coating to a wire and see how it does. It's too easy not to try.

http://www.asminternational.org/news/industry/-/journal_content/56/10180/17941766/NEWS

The idea of making something more thermally conductive thought...a current going through a wire is going to heat the wire pretty much evenly and if that wire is made more thermally conductive I don't see how that would help disipate heat. Wouldn't the material touching the wire and insulating it be the thing I want to make more thermally conductive?

The nanoworks link for the CNT motor above is only is 70% efficient? Why is it worse than copper


Here's the guy on the team's thesis paper
http://www.doria.fi/bitstream/handle/10024/98748/MasterThesis_FINAL.pdf?sequence=2

 

[gogo]

Sounds like silver might be feasible for the solid slot motors?
Subject: Dual rotor axial flux motor design

 

[major]

. But square wire looks interesting. Do you have any examples of mass production or special motors using square wire with success?

Hi Rat,

One of the more interesting applications of square copper magnet wire is the Remy. Some discussion here: https://endless-sphere.com/forums/viewtopic.php?f=30&t=45307&start=500

Regards,

major