It is pulsing 110V pulses at 1 KHz.What about duty cycle?
Duty cycle for a 555 based unit is dependant on the inductor chosen/built in order not to saturate it.It is pulsing 110V pulses at 1 KHz.What about duty cycle?
For efficiencies sake short heavy leads are a must.Probably this is most classic desulfator circuit I've found when was looking for such sort of things a few years ago:
The Desulfator I am using has a very narrow duty cycle, <0.01%.Did you checked scope waveforms etc to see how this desulfator waveform on battery terminals looks like and which is Vmax on battery during desulfation when this pulse hit its terminals?
I wonder too.Back in 1990 I worked at a place that sold UPSs. Some had been in storage for several years and the batteries would be replaced before sale. The old batteries would be typically at 1 or 2 volts. I experimented a whole heap with the old batteries and eventually had great success with the following formula: Apply a REVERSE charge with current limit set to 2% of Ah rating for 48-72 hours. The battery may not draw any current initially but just leave it alone. After this time, set the charge to normal polarity and charge for 3-4 days, still with the 2% current limit. During this time, do NOT be tempted to wind up the current limit - one cell will start to get hot and then it is junk. Fixed many new but neglected batteries this way. One 12v 24Ah SLA Yuasa started off at 2 volts and had been sitting for about 3 years, got it going and used it in my Diahatsu Charade for 2 years until I sold it.
interesting ... what does the reverse 2% trickle do?
Yes the schematic is a long copied one.For efficiencies sake short heavy leads are a must.Probably this is most classic desulfator circuit I've found when was looking for such sort of things a few years ago:
http://www.frontiersprings.com/desulfator.html (http://www.frontiersprings.com/desulfator.html)
However, I do not liked messing with inductors and 555 while it is was only a few lines of code on AVR to add support for desulfator mode to battery charger.
It doesn't mater how 1kHz frequency is created, but knowledge of proper duty cycle might be critical, so it will be difficult to compare different available desulfators without its waveform specyfication :-\
This is where the duty time is critical, they must not be allowed to saturate. Fet on time controls this and at turn off the released back EMF from the inductors collapsing field does the desulphating.Maybe this analog circuit with 555 needs some tricky :-/O to get it working, so of course never wasted my time to mess with its internals, however made of course simulation of this circuit in software to see how it works ;)
Maybe this analog circuit with 555 needs some tricky :-/O to get it working, so of course never wasted my time to mess with its internals, however made of course simulation of this circuit in software to see how it works ;)The 555 circuit IIRC only produced 2-3 Amp pulses @ 30 V and any reasonable variant will work to some degree.
This way power consumption to perform desulfator mode should be very low while duty cycle will be limited to 1%-5% so @ 24Vmax and it costs not so much kWh even during a few months of desulfation mixed with keeping battery at full charge at floating voltage 8)
Update: Probably will add AC mosfets switch to make automatic bypassing of inductor and slightly limit spike currents to levels safe for battery.
This is another interesting question-what optimum maximum desulfation spike current might be for 60Ah-70Ah 12V lead-acid battery? ::)
Power cosumption was never an issue the std desulphater as battery capacity and OC voltage increased while in use. :wtf: This is the desired result, but how can that be observed when you charge at the same time. :oTrick is this charger is powered from charged battery itself, so I can monitor its voltage all the time ;)
A further variant is to change the bridge rectifier to a single diode so that the cap gets charged to the peak of the mains voltage on the negative half cycle, followed by the SCR triggering near the peak of the positive half cycle.With MPU on PCB its better keep full bridge reactifier and measure input voltage on capacitors after full bridge and when it falls below given level (eg. 24V) than switch off PWM and wait in software for proper voltage, so with 250kHz ADC clock and 13 clock per ADC measurement one can monitor this voltage close to 20000 times per second.
All those little battery desulfators does not work at all.In general company with "LAB" in name smells always for the first time like bullshit before you verify their claims :-DD
http://www.sotolab.eu/eng/products.html (http://www.sotolab.eu/eng/products.html)
I recomand first to try to recharge the battery with a 50/60V dc power supply with a 110V/100W bulb in serie.Yep it is good idea, so simply such light bulb bypassed by mosfets switch might work to precharge battery to voltage where desulfator mode can be used 8)
'how feasible is this / can a general purpose test rig be built to cover the majority of desulfator concepts?If you follow another videos of this guy you'll find out that it uses this modified http://www.frontiersprings.com/desulfator.html (http://www.frontiersprings.com/desulfator.html) circut with bloody inductors and those videos was one of the best I found when was looking for this sort of things and starting point to make own MPU version.
Anyhow, after running a day that way, the voltage is still only at 0.05V, so I decided to run the reverse voltage thru the battery as suggested by Circlotron. Plan is 2-3 days that way, then reverse the voltage to normal.Make sure you limit the current to 2% of Ah capacity. Don't try to speed it up with more current!!!
If you place two batteries in parallel, I would place a good size inductor (like a 12V secondary of a transformer) between the two.Do you mean something like classic boost switching converter like this below where Vin is our power source and on Vout our sulfated battery in place of output capacitor? ::)
The date code of 12/10 will most probably be YY/MM so October 2012,
I'm on the fence with this particular one, but out in the feild we don't
give these any longer than 3 year's unless it's a Yuasa or Sonnenschein
which can still be ok after 5 years, dependent on installed system.
Back in 1990 I worked at a place that sold UPSs. Some had been in storage for several years and the batteries would be replaced before sale. The old batteries would be typically at 1 or 2 volts. I experimented a whole heap with the old batteries and eventually had great success with the following formula: Apply a REVERSE charge with current limit set to 2% of Ah rating for 48-72 hours. The battery may not draw any current initially but just leave it alone. After this time, set the charge to normal polarity and charge for 3-4 days, still with the 2% current limit. During this time, do NOT be tempted to wind up the current limit - one cell will start to get hot and then it is junk. Fixed many new but neglected batteries this way. One 12v 24Ah SLA Yuasa started off at 2 volts and had been sitting for about 3 years, got it going and used it in my Diahatsu Charade for 2 years until I sold it.
When a second parallel battery (or even a charger) is used to supply the voltage, that battery should be isolated from the pulse by an inductor to maximize the pulse into the sulfated battery.Fast diode can easy be rated for hundreds of amperes in pulse.
These devices are foolishness.Which devices? ???
I can see the pulses squared up nicely and are actually a duty cycle of 0.27%, or pulse width or 2 usec at 1.3 KHz. Pulses are 116V in amplitude.Could you post a photo how this bloody inductor is driven in your circuit, because of I can imagine inductor whcih connects two batteries eg. on its (+) terminals, so it is in series, but... it must be sosme kind of current limit-how do you drive this thing and how it looks like?
I seem to remember it was about the same as normal charging voltage, 13.65 for a SLA, 14.1 for a car battery. I never tried it on a car battery though.
Circlotron,
Yes I have the limit set to 190 mA, or 1.6% of AH rating.
How high in (reverse) voltage should I go? I have it limited to 13V right now, and it is drawing less than 1 mA.
Thanks,
I did some desulfation testing on an old 50ah car battery that had loosed more than two third of its capacity.I do not like idea of 0.2s huge amps pulses.
I used 50A peak current pulses of 200 ms with a 4s interval.
Results: after a few hours, the battery has completely lost its capacity ... totally dead!
It has been proven by official tests.Unfortunatelly, French is not my technical language, but really nice images and looks like a cool stuff-will try find something similar in English ;)
(See my links in my previous post.)
5) With low electric field, it's almost impossible to break a cristal....I never seen a cristal ocillator broken only by low oscillator voltage.When was designing my aluminium anodizing equipment, current needed was proportional to aluminium plates square area:
Your circuit definitively will not work for desulfating bateries, you waste your time and your money.This circuit was derived from other people work and it is still a concept not simulated in Spice but Falstad just to have some idea what to expect and whether I smell cooked ICs and see flying around capacitors or there is some hope that if it won't work I'll be able reuse components in another project and they survive :-DD
Stick to writing softwareIt is easier write software if you made also PCB, so my desulfator soft is ready and can't wait for PCB to check it out :-/O
“Imagination is more important than knowledge. For knowledge is limited to all we now know and understand, while imagination embraces the entire world, and all there ever will be to know and understand.”
- Albert Einstein
To understand how works desulfation of acid lead batteries, we have first to know how battery sulfation occurs.A lot of usefull informations about maintenance of lead acid batteries also can be found here ;)
I used a 24V 30A battery charger with triac control in the primary.How long time those pulses were applied?
Conduction angle was ajusted for 50A peak and conduction time controled by an ajustable NE555 oscillator.
...
For this reason, pulses have a 3 or 4s interval for not exceeding the maximum temperature of electrolyte.
Even with a few seconds interval if internal resistance of battery will be lets say 200 mOhm, than at 30A rms we have average 0.2s pulses energy about 180 Wats *0.2s / 4s = 9 W .A 50A peak 200ms current pulse with no current during 4s (T=4.2s), that's:
Need estimate this and compare with those "crappy" 555 based desulfators
Power dissipated in the battery (200mOhm internal resistance) = 0.2 x (10.91)² = 23.81WYep, I forgot that period is not 4s, but 4.2s, but we'll get similar result for... 10kHz pluses and 5us Ton, while 0.2s/4.2s~5% duty cycle and @ 10kHz period is 0.0001s with 5us ON time we get 5% duty cycle too, which means the same amount of power is needed 8)
You forget the rise and fall times.... :palm:Nope, I didn't forget but assumed this calculation is estimation only of not exact pulse energy amount, but rather magnitudes, just to see if is it 10x times bigger or lower in the case of 10kHz 5% duty cycle in comparision to those low frequency desulfation methods.
With 5µs pulse time, they are not negligible any more.
Lead Acid batteries are a waste of time and money.Please share your complete solution.
I almost see them as a lemon and nail type of battery :)
I have already 2 years of full OffGrid living and that will have been a nightmare with Lead Acid.
I hope a day will come soon when you will only see Lead Acid batteries in a museum.
Please share your complete solution.
And here is a 7 day graph with my house energy production / consumption data logged with theYour energy graph is cos(x) where x is angle between PV panels surface normal and sun rays, so using 2 axis sun tracker 30% more energy can be taken from the sun ???
It's not easy to find informations about this, it seems to be "secret of manufacturer".Nanopulser :bullshit: reveals his secrets :-DD
And here is a 7 day graph with my house energy production / consumption data logged with theYour energy graph is cos(x) where x is angle between PV panels surface normal and sun rays, so using 2 axis sun tracker 30% more energy can be taken from the sun ???
This is from my sun tracker software, based on Bird Clear Sky model ;)
SUN is: 2015-02-22.303 07:16:01 UTC (2457075.803 JD) lat: 50.***N lon: -21.*E Sun hour azimuth: 54.109 Sun (geo) azimuth: 125.891 Sun elevation: 13.644 Sun CSP power: 624.5 W/m2 Day of the year: 53
how about add more batteries, make them PV charge the banks endlessly ... then find more equipment to plug into the banks (shifting more over from grid powered) ?
I am still waiting for some scientific tests proving that such a little desulfator really works.Definitely want to do this with additional microscope support when new desulfator will be ready.
Can you provide me with a tracking device including strong supports for 72$ that can last for 25 years and not be destroyed by an occasional 100 to 120km/h wind ?I wouldn't like talk about offtopics there too much, but yes working and testing such sun tracking device while 3m in diameter parabolic mirrors dish for CSP thermal energy needs to be quite precise positioned to the sun-hopefully sun position on the sky is predicted many years ahead and only time and GPS position needed to adjust dish azimuth and elevation directly into the sun regardless sky is accidentally clouded or we have perfect clear sky and can also estimate amount of available sun energy.
Can you provide me with a tracking device including strong supports for 72$ that can last for 25 years and not be destroyed by an occasional 100 to 120km/h wind ?I wouldn't like talk about offtopics there too much, but yes working and testing such sun tracking device while 3m in diameter parabolic mirrors dish for CSP thermal energy needs to be quite precise positioned to the sun-hopefully sun position on the sky is predicted many years ahead and only time and GPS position needed to adjust dish azimuth and elevation directly into the sun regardless sky is accidentally clouded or we have perfect clear sky and can also estimate amount of available sun energy.
To make such things capable to survive huragans is rather mechanical design problem, not sun tracking electronics which can control different electric motors ;)
I took one writer's advice in this thread, and add some water to each cell--about 2 eyedroppers full each cell--and presto, it is now taking current.Rather basic, first thing is examine cells if battery is dead and add water if needed ;)
They replace the batteries in their client's alarm systems every year whether they need it or not ...It seems a little overkill...With no break's, we replaced such low capacity batteries (with fast-on connectors) every two years.
the stuff about reverse charging SLAs at 2% to remove sulfation.As far the battery is not completely discharged and voltage polarities of the battery are not inverted, reverse charging is the same as discharging the battery.
But I do'nt agree with this: completely discharge the battery will not desulfate the battery, nor charging with reverse polarities, it will only make the situation worse.I do want keep battery at safe volatge levels during desulfation and charging, so added in my desulfator prototype monitoring of input voltage pulse and battery voltage to triger switch in this based voltage multiplier desulfator when those voltages are at proper levels, so it will stop desulfation/charge if battery voltage will be above its floating voltage (will resume later when goes down or slightly discharge battery) or wait for input pulse voltage to be above lets say 10.5V, so another battery can be used as power source if someone wants to experiment more 8)
IEC 384-4 (Solid or Non-Solid Aluminum Electrolytic Capacitors) and IEC 384-18 (Solid or Non-Solid Aluminum Electrolytic Surface Mount Capacitors) specify that capacitors can withstand the following test conditions. After 15% of the rated voltage (derating the voltage at the maximum operating temperature) is applied for 125 hours in the reverse
polarity direction, and then, the rated voltage is applied for another 125 hours in the forward polarity direction at the upper category temperature (maximum operating temperature), there shall be no significant capacitor damage
It seems sure that the electric desulfation works, at least partially.We'll see ;)
Vo= 24.8V
Vc= 1.0V
t= 64s
R= 21k
C= 0.000949 F ~ 950uFExperimenting with the plates sealed inside the battery is working blind and so difficult to monitor.Internal resistance should improve as well as capacity in desulfated battery, so it can be tested.
We'll see ;)The fact that it seems sure that the electric desulfation works does not mean that any desulfator will work.
IIRC manufacturers suggest that deliberately charging a wet Pb battery at an elevated level will help to reduce any mild sulphation on the plates due to the vigorous hydrogen gassing that occurs (and associated & agitation of the electrolyte). Such 'treatment' is advisable only where any lost H2O may be replaced and where careful monitoring of the battery is possible. Deliberate excessive charging that causes large amounts of out gassing is not something that I would recommend unless you know exactly what you are doing. As a child of 10 I did something stupid with a 12V motorcycle battery ( I was collecting hydrogen gas in a bell jar !). There was a hydrogen gas explosion in the battery and it blew the case apart, covering me in dilute sulphuric acid and removing my eybrows :scared:Warning noted ;)
Please be careful ;)
Aurora
I am reminded of a story about a large company, which used a large number of electric forklifts. It involved a smoker who lit a cigarette, next to the large room in which there were around 40 battery boxes being charged, which resulted in the destruction of all of them along with the room. He, along with the operators of the charge station, survived mostly intact. He still smoked afterwards, too thick to take heed of the warning.The sparks from maintenence grinding near a battery charging can have a similar result.
Not such a big deal output high current in voltage doubler based desulfator I've changed for even higher currents and added axternal power supply.QuoteWe'll see ;)As I said before, professionals desulfators produce high current pulses (of the order of 50A peak for a 100Ah battery) of approximately 200 ms every 3 or 4s.