Hi Seamonkey
You can mail me that diagram.

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Hi SeaMonkey, heat is not a problem using the circuits i posted and yes these circuits cause the transistor to run cool to the touch and charge batteries very well and desulfating them. Though I'm sure if the transistor specs are exceeded it will heat up. Besides your suggestion is more complicated and costly, whereas a simple self oscillator will do the job. Whatever works for you i say.
peace love light
Tyson

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What is the output current you use to charge those battery? I ask because I usually use just maxed it .

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Thanks for the swift reply
Ive just revived a 2 years old 70ah car battery and a 12ah bike battery using groundloop circuit..... desulfate and used normal charger

I want to protect or isolate the circuit from the output as groundloop did

But i need also a fast charger instead of battery parallel connection between 2 cars i always forget to switch off my headlight or park light

Hope somebody can share a simple circuit with easily affordable and spare parts

totoalas

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Hello seamonkey,

I see you are well educated on the subject of battery desulphation and i need your advice. I recently obtained for few euros one large SUV type used and exhausted battery 12v 72Ah, that is Sealed Calcium lead type with a liquid indicator that shows it need replacement.

I have normally charged it till full (15v) and measured its capacity. It is more or less 2-3Ah! I then repetedly pulse charge it (40mH inductor, 3x6A10 diodes directly, IRF4229 Mosfet driven by a 555 circuit) Depsite all this efforts, the battery has exactly the same capacity. It does not seem to desulphate or anything do to gain any marginal capacity (pulse charge it at C20 cycle about 10 times)

The battery is in excellent physical condition like new looking, standing voltage 13 when discharged and 13,5 when charged

What do you suggest?

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From what you've described the battery does seem to
be a very good candidate for desulfation.

Can you tell whether the cells have sufficient electrolyte
water? If possible, add distilled water to the cells to
bring the electrolyte up to the proper level. Very frequently
a loss of battery capacity is caused by insufficient water
in the battery.

While desulfating/charging the measured voltage across the
battery may increase to an abnormally high value. With a
very heavily sulfated battery it may rise to over 30 Volts
(sometimes as high as 50 Volts) for some time before it begins
to decrease to a 'normal' value. This is a good sign when it
happens. Do not be alarmed should this happen with your
battery - it means that the pulses are having the desired
effect.

Desulfation can be a very slow process. If the sulfation that
has built up in the battery has acquired crystalline structure
it will be reversed only very slowly. Some batteries must be
pulsed for several weeks continuously in order to begin to
see signs of improvement.

Once the battery voltage stabilizes as a result of desulfation
allow it to charge to about 15 Volts. Some 'bubbling' is desired
so long as it is not too vigorous. While desulfating/charging the
battery do not let it become 'hot' to the touch. It may get
'warm' but if it gets hot damage is likely to occur.

Once the battery begins to show signs of recovery, perform
several cycles of desulfate/charge and test discharge. As
the battery is 'cycled' it should reach its maximum capacity.

Your battery is a good test case. Please keep us all informed
of your progress with it.

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My circuit is powered by a wall transformer supply rated
at 14 Volts, 400 mA, so I limit my input current to the
circuit to slightly less than 400 mA. For larger batteries
I approach the maximum; for smaller batteries (AAA or AA)
I may decrease the current to 50 mA or even less.

I control the current flow by adjusting the pulse width;
decreased pulse width produces less current flow.

I like to desulfate/charge the lead acid batteries slowly
to keep their temperatures cool to slightly warm.

With the NiCd or NiMH cells I pulse them until they begin
to get warm to the touch. Once they get warm they're
fully charged.

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It is possible to build a small 'beeper' device that
ties into the lighting circuits. It will 'beep' when
you turn off the ignition to remind you that lights
are still on.

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Hi seamonkey,

I noticed your earlier reply and tried something, and it gave me a question.

I used a joule thief with a secondary that produces a range of 147v to 1111v at 5khz.
I can change the pulse width by turning a rheostat pot at the pos input from the jt battery.

I had been using this output to spike repair a sla that probably shorted. I think that might be different from desulphated, not sure.

So, after I read that post about getting better results by changing the pw, I hand turned the pot a little. I took DMM voltage measurements at some points.

When the pot was letting the volts be over about 400v spikes, the DMM changed from 9.89v to -14v to -16v.
That is minus 13 volts to minus 16 volts.
I did this last night and the normal charger seemed to bring the battery to a higher level this morning.

I am wondering if you can first,
tell me if I did what you are suggesting?
and second,
What is this minus?
Is this something like what J Bedini calls negative or positive charge?

So,
Thanks for the suggestion and
Can you please explain this?

thank you,

jeanna

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I'm unclear regarding the pulse magnitudes you measured.
The pulses ranging from 147 Volts to 1111 Volts - where
and how did you measure them; with or without any load?
Are you taking the output pulses from the secondary
winding of a transformer in the collector circuit?


The variable resistance in the base circuit will cause the
pulse width of the oscillations to vary as well as the
consequent pulse amplitude at the output.

The voltage that seemed to change polarity - was that
measured across the battery being pulsed? If so, the
apparent change of polarity would be difficult to explain.

Can you make a drawing showing how everything was
connected?

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NAPA #782-1637 Lights On Buzzer


I killed many batteries on my old car I installed this and saved many batteries.

__________________
See my experiments here...
http://www.youtube.com/marthale7

You do not have to prove something for it to be true. However, you do have to prove something for others to believe it true.

Thank you. Interesting that you can power your circuit with such low amp rating power supply. I guess my circuit demand more than what amp meter indicate. Amp meter show only 250mA consumed from 2A transformer but the transformer can not keep up and drop its voltage!

Maybe burst consumption during on time can not be detected by the voltmeter / amp meter.

Same here. I currently charging 1000mAh nicad with 1.6V at 330mA output. Do not get even warm after an hour .

Still amazed to see that I can push 330mA to the battery without making them hot .

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How fast is fast?

My solution would be joining many coil output until it reach C10 of battery rating, 7 Amp for 70Ah battery. With my stingo, it may take 14 of them...

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Hello again. Thanks for prompt reply. I have read about sulfation and the voltage increase it creates. Actually i have studied the particular battery and does not show any sign of sulfation. By pulse charging it (i have tried also my small SSG) the voltage rises quite predictably and rather slowly as if the battery is new.
The only difference in behaviour i have noticed between a new battery and this is the capacity. Instead of having claimed 72Ah or even 50Ah it has... 2-3Ah ! Actually it shows no signs of sulfation to me, as it would take eagerly pulse or whatever charging.

...
regarding the electrolyte, i do not have a clue.
This is hermetically sealed type battery having a little clear indicator labeled (green-ok, black-need recharging, clear - needs replacing) Its clear, unless stired a bit that becomes OK, and when the electrolyte subsides becomes clear again.

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Thanks seamonkey I will install a relay and a mini tesla with led

I just rememered your name 32 yrs ago there is a brand seamonkey n novelty shhop where you can sse swimming monkeys in a glass of water hehehehe


Suchayo i am opting for a 10 minutes rapid charger portable

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The Calcium-Lead alloy batteries are frequently 'sealed'
and labeled 'maintenance free.' This is because the
Calcium tends to reduce gassing during battery charge
so the electrolyte rarely needs replenishment with water.

In order to see into the cells you'll have to devise a way
to open the tops of the cells where the vent is located.
It is in the middle of each cell, in the same place as a
normal battery has the removable cell cap. By very
carefully cutting into the plastic top you'll eventually
find it and be able to add water if needed.

Unless the battery has sustained physical internal damage
causing some of the plates to become detached, the
most likely cause of the very small capacity is a lack
of water.

Whatever the case, this battery will certainly become
a great 'learning experience' to advance your knowledge
and understanding!

Please keep us all informed of your results.

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Get hold of Chinese DC motor speed controller 250/350 watts 24 v. Connect TWO 12 volt batteries to the speed controller they are very cheap but you cant even make then for less then least 30 bucks as the fets alone cost quite a bit. They are found in many kids toys, electric bikes, scooters etc cost around 20 bucks. check ebay.

Now charge a single 12 volt battery from the DC speed controller and set the PWM "speed control" to around 50%.

Usually they come with lots of connects and wires for features on scooter but you only need power in and out and short the ignition switch wires together then add a 4k7 pot on the 3 throttle wires and set to 50%.

The battery being charged will be hit by 25Khz of spikes at around 15/20 amps and makes a good VERY fast car charger. The PWM makes a much better job then hooking up pure DC.

This is not for reviving old batteries but this will start a flat car battery usually within 5 mins so you can get going again.

As always put fuses in the right places!

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The NiCd is rather odd - while charging it will
actually absorb heat and feel cool. It is only
when it reaches full charge that it begins to
'gas' internally and produce heat as the
hydrogen is oxidized.

Many NiCd chargers sense this heat to
reduce charge current to 'trickle' for the
final 'equalizing' charge rate which is
safe and produces little heat even for
long periods of time.

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I measured these from the free ends of the secondary wires using a scope.
There was no load.
Sort of.
If you want to call the toroid of a joule thief the collector circuit.

These are the spikes produced by the wire that is wrapped around the ferrite toroid which freeloads off the action of the joule thief.
Most of my work has used this.
(I am using the joule thief withOUT al light as a pulse generator and studying what happens on this 'secondary'. Some people call it L3 instead of secondary)


Yes.
That is the reason I changed the charger circuit to this one.
This will allow me to vary the pw by hand.

Yes.
I connected the jt charger and it read 9.6v as usual across the battery terminals, but when I adjusted the pulse width to be wider letting higher voltage spikes with lower frequency therefore wider pulse it went negative.
After some time it became positive again.
When it became positive again it read about 9.4v

This morning the positive battery voltage was low again so I put it back on a regular charger and when that was charging the voltage of the 12v being charged went to 12.45v which is the highest it has reached since it originally died.

Do you still need a drawing?

thanks for this help.

jeanna

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Wow, good tips .

Using 555 driven 2N3055 radiant oscillator I would observe the heat right away, even at 10-15% ON time, sign of poor switching. I observe it on SLA and lead acid too.

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Your good explanation cleared things up!

Would it be possible to perform this 'experiment'
once again with the scope also across the battery
to monitor the pulsing waveform?

If you are able to duplicate the polarity reversal
while watching the pulse waveform on the scope
you may be able to see something which will
offer more clues. Something unusual apparently
happened which is difficult to 'diagnose' without
knowing more.

Could you tell us more about the JT inductors;
how many turns; type of core; etc...?

Since the pulsing voltage you've measured is very
high the impedance of the winding may be too great
for pulsing a battery. Ideally, the DC resistance
of the coil feeding the battery should be no
more than about 0.2 Ohms.

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Are you feeling the heat of the transistor or of
the batteries being charged?

The 2N3055 will produce a lot of heat while switching
heavy current flow. In order to assure that it goes
into deep saturation for minimum conduction loss
the base current pulse must be quite heavy. For
10 Ampere pulses the base pulse has to be about
700 mA of drive. Then, to switch it off quickly the
base current should go slightly negative with a polarity
reversal. Power Transistors are difficult to 'drive' for
efficient fast switching.

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Hi Bot1,
thanks for the tip as I am in
China they usually dont repair these things and just throw away
Now the hunt begins for the parts
Just a question for the pot 4k or 47k????will 2 7ah sla battery do the trick????


cheers

totoalas

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I think the throttles are 4k7 or some use a hall effect throttle. Yes 7aH gell batteries work fine and make a more portable booster charger unit. I have started a car many times off these batteries.

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Thanks again Bolt1
4k7 is 4.7 k Im learning
totoalas

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i missed this post... yeap, im working on a portable one inside a small wood box, to charge car batterys also.. will have connection to grid, and to 1.3Ah small battery!

i will try to charge my 9V non rechargeble batterys as dodosholdo!!

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Light, I Am!

You are Not a Body that has a Spirit, You are a Spirit that Has a Body! There is no Path to Peace, Peace is the Path!

Both. My coolest transistor operating temperature is around 10-15% ON duty cycle. On other duty cycle I usually can smell the heat too . Even at the coolest setting, it still heat the battery up considerably on 300mA.

Only after I use 2N3055 differently I observe cool charging on the battery.


Now I use different circuit that heat up the transistor real fast because of 50/50 duty cycle (self oscillating). I have to use heat sink. But any battery will be charged with very little heat even at 700mA charging current.


I think the running temperature of the transistor is not associated with batery charging temperature. You may still get hot batery with cool running transistor at high charging current. I hear some people able to do both cool, but I satisfied with just fast and cool battery charging .


I currently charge 2500 mAh nimh for 1.5 hours now at 250mA and the heat is barely noticeable on touch. I am more than sure that I will charge it much faster than specified 5 hours needed at that charging current, and do not have to worry about battery temperature too .



Agree, I have 4 times better efficiency than 555 driven 2N3055 now.

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Tantric
excited to see your new toy
Thelron Stark seem to be a guru in capacitor charging
His advice
thicker wires bigger bifilar air coil using solid plastic insulated cores
6 inches out dia 4 inches inside dia and 8 inches tall air core
Fast charging effect
Unfortunately his video response to Dodoshlodos channel was deleted

Hope this help
totoalas

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I devised a coil pulser (that takes several coils that i have on hand e.g. ferrite e-cores, laminated I-cores etc) that consists of a master astable 555timer (adjustable) that commands 2 x 555 monostable timers (adjustable) each one edge triggered at high and low period respectively.

Those monostable 555 control IRFP4229 power MOSFETs. I can work with 12v, 20v and 40V input. Frequencies can range from 2Khz down to 200Hz and pulse width 5% to 90%.

....
Concerning the particular battery, i pulse charge it for days and days and showed not sign of betterment. I drilled the top (sealed type) and substituted the acid (that was still strong) with distilled water and pulse charge it for many days. Nothing again. Then i substituted the water with new battery acid with a part of destilled water and continued the pulse charging, super-charging at low Amps and letting cool overnight.

I did not cycle the battery, only charging without end and add water to keep a certain level.

Today i decide to cycle it with a 20w bulb (74 Ah battery). It lasted almost 2 hours totaling 3,5 ampH draw. Last measurments was about 2 Ah draw from the same bulb. (1 hour last)

Battery behaviour have changed. Initially had a standing voltage 13,2v and below 12,5 volts its charge was decreased "exponentially fast" under the same load whereas now it has a standing 12,6v and the "break point" is 11,8 volts.

....
IMO, the battery has developed something upon its plates that prohibits the acid to do its function. Perhaps a chemical treatment is by far a better solution (since i saw betterment with changing fluid and not pulse charging).

Bellow few photos of my setup.

Attached Images

	1.JPG (59.8 KB, 13 views)
	2.JPG (65.8 KB, 12 views)
	3.JPG (53.9 KB, 10 views)
	4.JPG (56.4 KB, 11 views)

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Your description of your pulsing circuit sounds very
good. It should be effective.

What you've described so far with your battery sounds
like extensive sulfation, and it too is good.

Do you have a hydrometer to test the battery acid
strength with? It is the only way to find out for sure
whether the battery is fully charged, partially charged,
or discharged.

It is likely that even a sulfated battery would have
some percentage of acid still remaining in the electrolyte
solution and being able to 'read' its specific gravity will
tell instantly what the state of the battery's health is.

The higher than normal voltages are characteristic of
a sulfated battery. As are the declining voltages after
partial recovery. Typically, while desulfating a battery
by pulsing, the monitored voltage at first is quite high,
well above the normal 14 ~15 Volts.

Then, as the desulfation begins the voltage will drop to
an abnormally low level, well below 12 Volts. (Sometimes
as low as 6 or 7 Volts.)

Slowly, with continued pulsing, the voltage will begin to
climb until it eventually reaches 14 ~ 15 Volts and levels
off. At this point the sulfation has been largely reversed
and the battery is nearly rejuvenated.

Several discharge/charge cycles with continued pulsing
should bring it back to maximum capacity relatively
quickly.

It is not unusual to have to pulse a battery for many weeks
before it begins to show signs of response. Desulfation
takes time when it is done to a battery which has not been
used for months or years.

What you've described sounds quite normal and it seems
that the battery is responding. Don't give up on it! With
a little more work it should get even better.

You've done a good job of telling us all about your experience
and documenting your progress. You've provided much very
useful information to all who will be trying the same
procedure.

Tell us more as you continue.

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