Has anyone tried to wind a inductor from these ferrite beads from power supplies cables?

Thread Starter

douglas schroeder

Joined Jul 5, 2017
5
Hello everyone.
I'm new here.
I tried to find a similar question on the forum but I couldn't.
If this question is answered somwhere, please send me the link. thanks.
So, I need to make two inductors, one 1000uH 0.2A, and the other 220uH 3A.
I need them to a lead acid battery desulphator.
An the closest I could get was salvaging some ferrite beads from old power cords.
I plan to wind them as inductors.
Is that possible?
thanks
 

crutschow

Joined Mar 14, 2008
34,201
It's possible but it's hard to determine at what current the cores will saturate without measurements.
Do you have an oscilloscope and other test equipment?
 

Thread Starter

douglas schroeder

Joined Jul 5, 2017
5
Hello crutschow, thanks for the repply.
I may be able to get acces to a osciloscope.
I'm a bit naive about inductors, but I'm reading a lot.
What kind of measurements should I take?
The operating frequency should be at 1khz.
The dimensions of the toroid are: H= 28mm, OD=14m, ID=6mm.
thanks
 

tcmtech

Joined Nov 4, 2013
2,867
Yes but as crutschow says there's not way to know their specific inductive properties without doing some testing.

FWIW I have made a number those into simple push pull oscillator DC/DC converters before. No idea what frequency they ran at but they did work rather well and easily handled a few watts of power.

Now as for battery desulfating, unfortunately, the reality behind it is the odds are for what work you put into it you will never make enough gains in the long run to be worth the effort. About everyone on this forum plus a few million others have tried and so far the general consensus is it's a marginal value concept.
You only got to get stranded several miles walk from home 1 - 2 times and/or have to bum a jump start off strangers while in town 2 - 3 more, because batteries you were sure you recovered where good gave up on you in the worst time and place, before you abandon the idea and just start taking your old batteries in for core exchanges on new ones like everyone else.
 

Sensacell

Joined Jun 19, 2012
3,420
Those cores are intended to reduce electromagnetic emissions, they are often made of "lossy" core materials.
The idea is to dissipate the unwanted RF energy in the core, exactly what you don't want in a power inductor.
Not going to make very good inductors.
 

Ylli

Joined Nov 13, 2015
1,086
I just want to reiterate what Sensacell said. These ferrites are designed to be lossy, and as such do not make good inductors.
 

GopherT

Joined Nov 23, 2012
8,009
Thanks for the reply tcmtech.
Unfortunately at this moment I can't afford a new battery.
So I will give it a try.
The fast way to desulfate a battery is to rinse out all the acid (carefully) and refill with 1 Molar sulfuric acid ( battery acid) available at Advance auto parts. Sometimes it works, sometimes not. A new battery is the easy and ultimately cheaper solution. Any attempt to get a few more months/weeks of life out of a battery is not worth the effort and expense.
 

tcmtech

Joined Nov 4, 2013
2,867
Thanks for the reply tcmtech.
Unfortunately at this moment I can't afford a new battery.
So I will give it a try.
Unfortunately the way the vast majority of batteries are made the plates are so thin that once they sulfate they are effectively physically damaged beyond recovery as well.

Think of it as having an equal amount of rust corrosion on a steel can Vs a Steel plate. The amount of rust that would destroy the can is superficial damage to the plate at best.

That's the reality of what you're dealing with so unless you're working with a higher end heavy built severe service duty type deep cycle battery you basically have so little electrode plate material to work with there is nothing to recover and rebuild through desulfating.
 

Thread Starter

douglas schroeder

Joined Jul 5, 2017
5
Thanks for all the replies.
Well, I think it is sulfated because I can get it to around 13v, but it doesn't hold much capacity (Ah).
I saw many people trying these desulfators and apparently getting good results.
But I'm getting a bit skeptical.
If I don't get much of a trouble building the desulfator (finding a good inductor), I may give it a try...
Has any of you build one?
 

SLK001

Joined Nov 29, 2011
1,549
...or have to bum a jump start off strangers while in town....
That is why I drive a stick. My 6 year old battery went from just fine to no-longer-holds-a-charge in just 3 days, and I was going cross country in 10 days. While I was providing the "starter motor" for the vehicle, the AC didn't work. I thought that the alternater could provide enough juice to power everything in the vehicle - I guess not. Anyway, a trip to WallyWorld got me a replacement battery for $52, which I installed in the WW lot. Fortunately, the new battery even fixed the AC.
 
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