simple desulfator circuit - question

[chemelec]

hi, "probably" is not enough for me.. either it does or it doesn't

the design i think it is from a magazine...found the pdf on a forum..but i guess its not allowed to upload here so i gave a link of the schematic i found on google...

by the way check this out..this guy sells them on ebay look how small both inductors are..


**broken link removed**

NorthGuy at the battery i was measuring voltage...

4pyros so i guess as the voltage falls the frewuebcy will raise?

PDF's are Allowed here.
Magazine? Anyone can create a PDF.

I Don't have a 100ma Inductor to actually Test one.
But Since the Current in this circuit is GREATER than 100 mA, I would say it is Saturating.

I am Quite sure a 1 Amp inductor would be OK.

The Chokes I wound are only good for about 1 Amp and it definately worked OK for my Bench Tests.
Both the Batteries I was Using were 4 A/H GELL CELL's.

The SIZE of the Inductor Does Not Necessarly Represent the Current Rating.
These Power Inductors are Wound on FERRITE CORES.
And they can be quite small even for higher currents.

 

[NorthGuy]

The amount of voltage rise will depend on the battery size. For it to go from 12 to 50V with, say, 1A, It'll need 40 Ohm internal resistance. I don't think it's ever possible even for very bad and very small battery. How much your voltage rise?

You can experiment. Discharge a battery completely, then let it sit discharged for couple weeks in a warm place. At this point it'll be completely sulphated, so you can charge it (if you can) and then try to desulphate. Of course, if you cannot charge it, the desulphator won't work.

 

[lynx]

i agree, the wire diameter defines the current it can withstand, but what i was trying to say is that these cores
cannot accept thick wire so you can have 6A and 220uH, read again my previous post, i've edited it..
and i guess that edit is the last question i wanna ask you, if you like to reply

 

[chemelec]

i agree, the wire diameter defines the current it can withstand, but what i was trying to say is that these cores
cannot accept thick wire so you can have 6A and 220uH, read again my previous post, i've edited it..
and i guess that edit is the last question i wanna ask you, if you like to reply

Well I SERIOUSLY DOUBT those Inductors are Rated at 6 Amps.

However On Higher Current Inductors, they sometimes use "Litz" Wire to get Higher Currents in smaller Size Inductors.

At Higher Frequencies and/or for Sharp Pulses, Current Flows on the Outside of the wire.
Using Multiple Small Wires in Parallel (LitzWire) can be Much Better.

 

[lynx]

I don't think it's ever possible even for very bad and very small battery. How much your voltage rise?

hi, i don't know..(i can't be sure...)

this is from the battery (scope/probe X1, 100mV/DIV :


and this is from the pin #3 of the 555:

as you can see the frequency constantly flactuates, it is never steady...
right now the battery it's 11.30V (with load) and a little over 13V without load.

to tell you the truth i'm not expecting anymore that this device can fix the battery
probably waste of time and money...funny thing i've spent extra hours to make a pcb for it.

 

[4pyros]

to tell you the truth i'm not expecting anymore that this device can fix the battery
probably waste of time and money...funny thing i've spent extra hours to make a pcb for it.

It will only work if the battery is not to far gone. Try it on another battery. Use it on the one in your car to make it last longer.
It was not a wast of time.

 

[NorthGuy]

100mV/DIV

So, it goes up only 0.07V? And battery is 13V whithout load. These are signs of the battery being relatively healthy. 13V might be a little bit too high for the resting voltage, could be some stratification or low electrolyte. What kind of battery is that? Is it flooded? Does it have caps that you can open? If so, can you look inside at the electrolyte level (don't forget goggles)? Why don't you like it in the first place?

 

[chemelec]

Well I SERIOUSLY DOUBT those Inductors are Rated at 6 Amps.

However On Higher Current Inductors, they sometimes use "Litz" Wire to get Higher Currents in smaller Size Inductors.

At Higher Frequencies and/or for Sharp Pulses, Current Flows on the Outside of the wire.
Using Multiple Small Wires in Parallel (LitzWire) can be Much Better.

Unless your using Very Low Quality Caps or Resistors the Frequency should remain Quite Stable.

hi, i don't know..(i can't be sure...)

this is from the battery (scope/probe X1, 100mV/DIV : View attachment 84790 View attachment 84791


and this is from the pin #3 of the 555: View attachment 84792

as you can see the frequency constantly flactuates, it is never steady...
right now the battery it's 11.30V (with load) and a little over 13V without load.

to tell you the truth i'm not expecting anymore that this device can fix the battery
probably waste of time and money...funny thing i've spent extra hours to make a pcb for it.

Unless your using Very Poor Quality Caps and Resistors, Or have a Substantial Temperature Change, The Frequency should remain Quite Stable.
My Frequency doesn't vary more than about 5 Hz.

The No Load Voltage Doesn't mean Much, Unless the battery has been left setting without a Load or Charge, for a Long Period of time. (24 Hours)

 

[lynx]

What kind of battery is that? Is it flooded? Does it have caps that you can open?

it's a bosch silver

here's what happens if you try to open it

the battery is not all right..if it was i wouldn't enter into the trouble doing all these...though you've made me sceptical
with what you said about stratification, awhile ago i found an article about it and i know what it is.

chemelec resistors it is suppose they are 1% tolerance...the capacitors aren't top quality, but they suppose to do
their job, somewhere i think i've read that the 100uF should be low esr, but i didn't paid much attention and i
didn't bought low esr, which would be 4 times the cost of a normal capacitor.

4pyros thanks for your encouraging words, but how come a 70mV-300mV pulse can restore a battery?
from the explanation chemelec gave me, that's what i've understood...

"So assuming battery is 12.6 volts and a 0.3 Volt Spike, Total voltage would be 12.9 Volts as the Spikes Occur."

 

[4pyros]

4pyros thanks for your encouraging words, but how come a 70mV-300mV pulse can restore a battery?
from the explanation chemelec gave me, that's what i've understood...

I still don't think you are trying to read the pulses right.
Have you tried it on a good battery?

 

[chemelec]

I still don't think you are trying to read the pulses right.
Have you tried it on a good battery?

it's a bosch silver View attachment 84799

here's what happens if you try to open it

the battery is not all right..if it was i wouldn't enter into the trouble doing all these...though you've made me sceptical
with what you said about stratification, awhile ago i found an article about it and i know what it is.

chemelec resistors it is suppose they are 1% tolerance...the capacitors aren't top quality, but they suppose to do
their job, somewhere i think i've read that the 100uF should be low esr, but i didn't paid much attention and i
didn't bought low esr, which would be 4 times the cost of a normal capacitor.

4pyros thanks for your encouraging words, but how come a 70mV-300mV pulse can restore a battery?
from the explanation chemelec gave me, that's what i've understood...

"So assuming battery is 12.6 volts and a 0.3 Volt Spike, Total voltage would be 12.9 Volts as the Spikes Occur."

1) That appears to be a SEALED Battery and NOT MENT to be OPENED.
I Never Buy those types.

2) The Only Capacitor that determines the Frequency is that C1 (.002), Plus R1 & R2 (470K & 22K).
(And the Measurements you previously gave When you measured them Were WAY OFF, ESPECIALLY If they were 1% Resistors.)

3) The Theory is: "The Sharp Spikes are Supposed to Break Up the Sulfation".
However on This Desulfator, Those Spikes are NOT VERY SHARP.

4) And the 0.3 Volts that I measured is a result of that battery's Internal Resistance.
Depending on the Physical Size and Condition of the battery being desulfated, It can be Lower or Higher than this.

 

[chemelec]

Here is the Scope Picture of My Desulfator, On that SAME Sulfated Battery.
Notice how SHARP these Spike are on My Desulfator!
Also about 0.8 Volts, compared to 0.3.

There are a Lot of Poorly Designed Projects on the internet.
Also MANY that Don't work at all.

 

[lynx]

yes i can see it...maybe it's my oscilloscope's issue? but still i don't get it...how 0.8V
can desulfate a battery?!

i have also bought spare components, i'll measure them again in case i did wrong measuring their
values.

[EDIT]

R1 471K, R2 22K, C1 2.4nF my spare parts seem to be exact...also awhile ago i charged
the battery again, now pin #3 is around 1.2KHz the fluctuation is 10-20 Hz, constantly
it goes up and down, it never remains steady, i could use these components instead
but i think nothing is going to change most likely it's the battery's voltage level
that changes the frequency..

 

[chemelec]

yes i can see it...maybe it's my oscilloscope's issue? but still i don't get it...how 0.8V
can desulfate a battery?!

i have also bought spare components, i'll measure them again in case i did wrong measuring their
values.

[EDIT]

R1 471K, R2 22K, C1 2.4nF my spare parts seem to be exact...also awhile ago i charged
the battery again, now pin #3 is around 1.2KHz the fluctuation is 10-20 Hz, constantly
it goes up and down, it never remains steady, i could use these components instead
but i think nothing is going to change most likely it's the battery's voltage level
that changes the frequency..

As I Said before, The Frequency is NOT THAT IMPORTANT.
But the 1.2Khz sounds Correct for these values, compared to your Previous Frequency tests.

As I Also Said before: The Theory is: "The Sharp Spikes are Supposed to Break Up the Sulfation".

And as that ADVERTISEMENT on Ebay Said: Possibly up to 4 Weeks to get Results.

"I guess it is like Giving a person a Mild Shock for Many Days".
Definately would change him also.

I Have no idea Who was the first to come up with this "THEORY", or what was the Origional Circuit.
Definately NOT the one you made.
But SOMETIMES a GOOD DESULFATOR WILL Help to Recover a Battery.

If you have a LAND BASE PHONE in Greece, I can call you Toll Free to discuss this.
(9 Hour Time Difference)

Take care......Gary

 

[NorthGuy]

the battery is not all right..if it was i wouldn't enter into the trouble doing all these...though you've made me sceptical with what you said about stratification, awhile ago i found an article about it and i know what it is.

I tried to look on the Bosch site, but they don't give much details. It's hard to see, but the black round thing on the right looks like a cap. If you remove plastic cover, you should be able to see 6 of these.

If they're designed to be unscrewed then these are flooded cells and if you open them you should be able to see inside cells. There must be plates over there covered by acid. If acid level is below plates then this is the problem with the battery and can be alleviated by adding water followed by controlled overcharge. Wear goggles so that the acid doesn't get into your eyes.

If they don't unscrew easily, this must be Gel or AGM VRLM battery and there's nothing to look at inside it.

 

[lynx]

hi awhile ago i had the battery for 2 hours connected to a charger at 16V after that i turned it upside down ans shaken it so the electrlyte can mix better i did that just in case theres stratification.. the outcome is zero.

chemelec check the conversation i opened

though i respect your opinion and obviously you know bettet than me... i dont think 0.07-0.8V its much of a shock for a battery of that size...

 

[lynx]

NorthGuy the black hole is hydrometer mine doednt have it...those photos are from google for reference...the battery is closed type

[EDIT]

i found a dead battery from a car service, it was around 7v.. then i added
the desulfator and i probed the poles with the oscilloscope what i saw was
a huge pulse over 300mV i didn't had the chance to check the exact value
because after 25-30 seconds it falled close to 80mV

Gary (chemelec) seems you're right on everything you told me up to now...
but i got bored searching around this circuit, so what i'm going to do is
to fully charge the battery and let the desulfator work for around a month
and then i'll check again if it restored.

guys thanks again for all your help, i've learned interesting new things
i didn't knew about batteries and generally on electronics, though my
main goal was to fix that battery, but i guess time will show

 

[NorthGuy]

NorthGuy the black hole is hydrometer mine doednt have it...those photos are from google for reference...the battery is closed type

Not much you can do with a sealed one.

There are different reasons a battery can fail. Sulphation is only one of them and happens when battery is left discharged (or partly discharged) for a long time.

Elevated resting voltage is not a symptom of sulphation, but rather a symptom of overconcentrated electrolyte, which happens if you charge at too high a voltage or for too long. Battery simply dries out. With flooded battery you can add water, but nothing you can do with a sealed one. Charging it with 16V could've removed even more water, and you cannot replenish it

 

[chemelec]

hi awhile ago i had the battery for 2 hours connected to a charger at 16V after that i turned it upside down ans shaken it so the electrlyte can mix better i did that just in case theres stratification.. the outcome is zero.

chemelec check the conversation i opened

though i respect your opinion and obviously you know bettet than me... i dont think 0.07-0.8V its much of a shock for a battery of that size...

What your Not Understanding is that 0.8 Volts is the Voltage under Load of the Battery.
On a Really Badly desulfated battery that Voltage might be 3 volt or more.
It Depends on the Battery's INTERNAL RESISTANCE.

The Lower this Internal Resistance is, the "CURRENT of this Spike" in a Desulfator must be Much Greater to create a Higher Voltage.
And a Battery that is Already BAD, Definately Can't deliver HIGH CURRENT to a Desulfator, to create a Higher Voltage Spike.

A NEW, Large 12 Volt Car Battery has a Very LOW Internal Resistance.
That is Why they can deliver Hundreds of Amps into a 12 Volt Starter.

Smaller, but good Batteries have Somewhat Higher Internal Resistance, so they Can't deliver nearly as much current.

A Battery with a BAD CELL or a battery that is badly sulfated has even a Higher Internal Resistance.

If a Desulfator was made for Direct Mains Power, Than a VERY HIGH CURRENT SPIKE, with a Very High Voltage could be Created.
But That Spike would Probably do MUCH MORE DAMAGE than Good.

Everything has its LIMITATIONS.
Sorry I don't know How to explain this any better to you.

 

[chemelec]

If you want a HIGH POWER Desulfator, I can give you a schematic for one!

It can be made to operate from 110 Volts AC.
Or Modified for operation on 220-240 Volts AC.

It is Not easily done, as SELF Operating from the Battery.