WF-138 WF-139 Charging Video's [ Pulse ]

[old4570]

http://www.youtube.com/watch?v=QKy0mx55Qy4

I video'd the pulsing of the WF-138 ....
The Camera sux's hard for focus , I taped it some 8 times and this was the best one ...

http://www.youtube.com/watch?v=rcON1l_otVg

WF-139 Pulsing away ...

Sorry guys , wasnt done yet ,,, I have a 18650 in a battery holder , connected to the charger with a AMP meter inline to watch the current flow ... [ 1A meter ]
I havent seen the voltage pulse with these chargers , but I thought it would be interesting to watch the current pulse ..
Ive been waiting for these 18650 holders for a while , as I wanted to set up a test rig for watching chargers with , second video shows the set up some , but the Kodac EasyShare C613 blows for focus , worst focus ever , and there is a video camera somewhere ?? ill have to dig it out , I usually take stills ..

Battery was a Trustfire Grey 2500mA [ There claim ] @ 4.05v

 

[VidPro]

Re: WF-138 Charging Video [ Pulse ]

this is the current? Isnt this an old4570 thread ? he always tells us the test parameters. i swear.
it's stopping to test the actual battery voltage?

 

[VidPro]

Re: WF-138 Charging Video [ Pulse ]

oh i got it, it is voltage, a mostly discharged battery.

 

[old4570]

Re: WF-138 Charging Video [ Pulse ]

You guys rushed in a little early ...

Anyhow's , its the current [ AMP's ] being measured , and I just wanted to catch the pulsing on video ...

 

[liveforphysics]

Pulse, check SOC voltage, pulse, check, pulse, check...

Thanks for the vid!

 

[old4570]

I knew it was checking the batt V , but it looks like its doing it almost every second , and I did not remember the WF-138 doing it anywhere as much as the WF-139 .. Live and learn hu !

Damn , if one had the time and money !
One would buy 10 WF-139's some 40 ?? Brand batteries , and charge and discharge the batteries to test for cell degradation [ if any ] , and at what point [ if any ] the cells began to degrade [ if any ] from this form of charging of Li-ion ..

So if the batteries are on the charger 4 Hours , your looking at some 14,000+ Pulses , 10 recharges would be 140,000 pulses + [ WF-139 ]

 

[fran82]

Sorry, what does it mean? those chargers are good or bad?

 

[old4570]

Sorry, what does it mean? those chargers are good or bad?

That !!!!! is the million dollar question !!!!

 

[VidPro]

Sorry, what does it mean? those chargers are good or bad?

at least it means it is checking the battery

so next thing to show, might be what happens when battery reaches some specific voltage? and charger does something different? or not?
remembering of course that a small ammount of added resistance exists to be able to see what is going on.

the pulses dont bother the battery none, although this is not "pulse charging" by definition yet, pulse charging studies have almost always shown to give good results.

 

[liveforphysics]

I knew it was checking the batt V , but it looks like its doing it almost every second , and I did not remember the WF-138 doing it anywhere as much as the WF-139 .. Live and learn hu !

Damn , if one had the time and money !
One would buy 10 WF-139's some 40 ?? Brand batteries , and charge and discharge the batteries to test for cell degradation [ if any ] , and at what point [ if any ] the cells began to degrade [ if any ] from this form of charging of Li-ion ..

So if the batteries are on the charger 4 Hours , your looking at some 14,000+ Pulses , 10 recharges would be 140,000 pulses + [ WF-139 ]

Keep in mind, you discharge in PWM pulses. About 360,000 discharge pulses per hour of use for a light with a PWM freq of 100hz.

 

[old4570]

Lets not forget the voltage thing as well , [ WF-139 ]
I think mine charges at 4.92v [ batt @ 4.04v ] or 0.88v above battery voltage .

So what interests me , is the long term effects the voltage + pulsing may have , on Li-ion . And as to how good pulsing is for Li-ion , I do believe there are many varied opinions .

The trustfire TR-001 charges with a steady current and 0.18v over batt voltage .

It would be very interesting to see which charging method is superior for battery life [ least degradation ] , and how many cycles through a charger before anything shows up .

Anyhow , plenty of room for some one to explore ...

 

[old4570]

Keep in mind, you discharge in PWM pulses. About 360,000 discharge pulses per hour of use for a light with a PWM freq of 100hz.

Yeah , but thats on the other side of the driver ... [ To the LED ]

 

[jirik_cz]

Lets not forget the voltage thing as well , [ WF-139 ]
I think mine charges at 4.92v [ batt @ 4.04v ] or 0.88v above battery voltage .

Are you talking about open circuit voltage or did you measure actual voltage during the charge?

Yeah , but thats on the other side of the driver ... [ To the LED ]

For example simple AMC7135 driver with PWM dimming has definitely PWM on the both sides of the driver. There is nothing to smooth out the input current.

 

[45/70]

......pulse charging studies have almost always shown to give good results.

I've researched this to some degree and came to the conclusion that this article, pertaining to "burp" charging, sums it up quite well. Pulse charging of NiCd/NiMH cells anyway, doesn't seem to hurt anything, but it has been shown that it doesn't really do anything either. There is some evidence that it is good for Pb batteries, as it supposedly knocks the crud off of the plates, but I'm still not sure about that either.

As for Li-Ion cells, this seems to be a bit of an unknown area.

It would be very interesting to see which charging method is superior for battery life [ least degradation ] , and how many cycles through a charger before anything shows up .

You would think that the cell manufacturers would have looked into this, and I'm sure they have, and apparently don't think much of it. If they did, I'd think they would recommend and implement such a charge method. It would be in their best interests to do so, and if nothing else, at least some of them produce chargers, as well. As fierce as the competition is though, there are none that I know of that recommend, or produce such a charger for Li-Ion cells.

Anyhow , plenty of room for some one to explore ...

Oh, I'm with ya there.

Dave

 

[VidPro]

negative pulse charging, was actually discharging the cell when charging it, if it accomplished anything it cycled (so to speak) the battery more while charging. I suppose it could be more usefull on a cell that needed cycling, and therfore any contiuous tests on any good or once cycled cell would not show any progress.
plus it didnt cycle all of the cell, as that would conflict with it actually getting charged ever.

I have applied the Discharge while charge pulse method, to voltage depressed batteries to attempt to accomplish more discharge cycles (so to speak) on a single charge cycle, How do you test that, when once the cell has been cycled, it is already cycled once. say you have a 25% discharge between charge pulses, that is only cycling it 25%, yet a full discharge and charge by ANY means cycles it 100%.

if you want to show results from this charge discharge thing, then put a cell in that needed that, then have it be rediculous ammounts of back and forth, plus on ni-mhy it would be heating in both directions.

Pulse Li-Io charging has been tested at some university where they showed that on continual cycling the battery that was hard pulse charged vrses normal rate current control, the normal battery was at 80% holding capacity and the pulse charged battery was at 90% holding capacity after 500cycles or so.
basically the alogrythm was 50-50% 2X rate 1Sec on/off no discharging during. but they are the usual accelerated testing, where they just yo-yo the battery to get the testing done.

there have been other tests too, recentally some students are testing high frequency higher speed li-ion charging, and believe with it they can fast charge , and get more cycles. but they are doing computer models, gee i can make perpetual motion in a computer model.

I have achieved gas re-integration on a Hard pulse charging, when normal charging did not act the same way, and use pulse charging regularly , but i still have no idea as to some perfect pulse speed, just do it because it has shown to work, is no slower, and the batteries that get it do great, especially the great batteries

there are other studies on hard fast pulse charging done via pitri dish batteries the results are always claimed to be wonderfull, but what good is a pitridish to reality.

Because high RATE is not recommended for li-ion batteries, how would a person "Form" a li-ion battery for a high rate without it? with the methods tested they hit with high rates, with gaps, so they achieve high rates without causing problems. no heating, no overrunning, no resistance change, no overcharge, no damaging the chemicals, no PCT in the way.

What it can do is amazing , i have seen it make batteries last way longer, fix ones that are not doing well, provide more discharge capacity under loads. But you will have to BUY my paper for $25 to get the results, and have the proper method for doing it :devil: plus my $250 magic fix-all battery charger isnt out of the wherehouse in china, and were having trouble with the japanese translation of the manuel :devil: Nessisary to translate the english into giberish before distribution. Plus "marketing" is having trouble with legal, they cant use enough fraud, deception, and lies to suit them:naughty: and the safety disclaimer is 457 pages long, which takes longer to read than the warrenty or unit lasts. Plus the recent meltdowns of the units just minor software glitches , and the iphone app still needs pretty pictures in it

just try it! that is all i can say, it has some logic. it is easy to do.

 

[old4570]

Are you talking about open circuit voltage or did you measure actual voltage during the charge?

Open circuit = 4.94v / one cell occupying = OC 5.15v
If cell is 4.05v , charge voltage = 4.12v , and there is a slower pulse on the voltage but it seems to go up and down around 4.10v and 4.12v [ variation ] and the pulse is 0.01v ..

Sorry , shouldn't post around midnight .



For example simple AMC7135 driver with PWM dimming has definitely PWM on the both sides of the driver. There is nothing to smooth out the input current.

Yeah , PWM is the circuit opening and closing ...
Up way to late !

 

[45/70]

Yes, that article was in reference to negative pulse charging, which is a particular form of pulse charging. The general consensus though in my research, was that for NiCd/NiMH cells, pulse charging in general, had no real benefit to the cell. It is a cheaper method of building a charger with variable charge rates, such as the Maha C9000 and many others. The components used to make a charger that charged cells at many different rates without using PWM would be far more expensive to produce. In the end however, most results conclude that, for example, a cell charged at 1000mA vs. a cell charged at 2000mA using a 50% PWM charge rate equaling 1000mA, resulted in the same amount of charge, in the same amount of time, with no other obvious benefit. Yes, as I said, not all agree on this.

Pulse Li-Io charging has been tested at some university where they showed that on continual cycling the battery that was hard pulse charged vrses normal rate current control, the normal battery was at 80% holding capacity and the pulse charged battery was at 90% holding capacity.
basically the alogrythm was 50-50% 2X speed 1Sec on off. but they are the usual accelerated testing, where they just yo-yo the battery to get the testing done.

Beware of university studies. Often the conclusion is determined before the study is done. The goal of many such studies is "to show that", and they often lack any supporting evidence that would prove otherwise.

As I said, Li-Ion charging may be a different story, but for the reasons I pointed out in my last post, I'm still looking for further proof, and as of yet, I have not seen any. It could very well be that there are better ways to charge these cells. I'm sure things will change. They always do. That's progress, and I wouldn't find it the least bit surprising, but "show me".

Dave

 

[Art]

Lets not forget the voltage thing as well , [ WF-139 ]
I think mine charges at 4.92v [ batt @ 4.04v ] or 0.88v above battery voltage .

So what interests me , is the long term effects the voltage + pulsing may have , on Li-ion . And as to how good pulsing is for Li-ion , I do believe there are many varied opinions .

The trustfire TR-001 charges with a steady current and 0.18v over batt voltage .

It would be very interesting to see which charging method is superior for battery life [ least degradation ] , and how many cycles through a charger before anything shows up .

Anyhow , plenty of room for some one to explore ...

Did you measure the charging AMPs of the TR-001?

I have here a Cytac , a WF-139 and a TR-001... the Cytac is charging at 1A and the other two between 550 and 450ma.
Strange thing is that I dont see that pulse on any of this 3 charges :thinking:
Maybe its my multimeter that does not show the pulses... can it be?

Regards,

 

[VidPro]

resulted in the same amount of charge
There should be no capacity difference , in a hard pulse charge than a normal rate continuous, unless the cell was in dire need of of that, and it would be to late at that point.

Testing would have to show that the plates maintained longer over time, and/or the cell was more capable of higher rate of discharge. Because some rates of discharge ruin the cell, and time takes forever, it isnt going to be me who gets that data $$$. all my chargers are different, and i wouldnt have a "control" and they are in use to often, to dedicate.

with ni-mhy using the different rates and pulsing would alter the termination so differently any results using V-drop termination would be useless, even Ni-?? voltage max alogrythms would have a hard time creating "control" when 2 differences were applied (both rate and pulse). at least with li-ion you can get down to a float termination point that isnt all over the place, as variable, but it would still be subjective to say that the differances in method broke there being a "control" or ability to compare 2 things that are not exactally the same.

 

[old4570]

Hmmmm , wondering out aloud ..

So if you got a nicely matched pair of RCR123A's [ faster to charge and discharge ]

And charged and discharged , [ WF-139 charger and PWM for discharge ]
And the other was charged CC CV or as near as possible
and discharged direct drive or non PWM ....

Now obviously it would not be a large enough sample , but doable .
Both cells would need to be charged at or near the same rate and same goes for the discharge rate [ as close as possible ]

Both cells would need to terminate as close together as possible [ maybe lights with 3v protection ] .. Discharge rates should be such that the tester could walk away and not have to continuously monitor the discharge [ whilst watching TV or what ever , and maybe get in two charges and discharges a day , so after a month [ maybe ] something may or may not show up .

:thinking:

Well , just thinking !

Good or bad , the WF-139 is the most talked about charger Ive ever seen .