PEG cell replica and PEG properties

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  • Last Post 30 August 2024
AbitAnnoying posted this 13 August 2024

Hello, so I want to share with you my experiments with PEG cell. 

My current main cell.

PEGcell C-C PEGcell C-C

Construction -Electrodes are burnt and properly cleaned carbon rods from A batteries (ordinary large Zn/C cells). Electrolyte pure PEG8000. I covered the electrodes with melted PEG. I previously let the molten PEG stand in an open container for about 20 minutes at about 90°C (194°F) to evaporate some moisture, but it certainly wasn't enough to dry completely. But I honestly have no idea how much moisture is in it. When PEG cools it shrinks. To prevent cavities from forming, I added melted PEG several times during cooling.

From pouring to complete solidification, I applied high voltage pulses to the electrodes. The source was a small HV source (4.55kV/95uA) which charged 2 capacitors (2x680pF/6kV in parallel) via a potentiometer (3-16MOhm, to regulate the frequency of pulses) and these were then discharged through the spark gap (at about 3kV) into the cell. I don't know the frequency of the pulses, it could have been tens to hundreds of Hz. I don't have a photo of the process, I didn't take many photos of these beginnings, the values ​​are mostly on paper, sorry. (

HV pulz source

caps

HVsource

Unfortunately, I didn't measure the voltage and current before the HV pulse process (I regret it now). Here is the voltage and current of the cell after applying HV pulses and some time after (Measured with a 10MOhm multimeter) -

Day1.- Immediately afterwards U-1.8V / I-1.35uA

           Voltage after short circuit when measuring current U-1.56V

           Another longer current measurement (10s short circuit) I-1.2uA stable for 10s 

The first day I also watched the cell on the oscilloscope, I will describe below.

Then I just measured voltage and current for a few days.

Day2.- U-415mV / I-0.21uA

Day3.- U-246mV / I-0.14uA

Day4.- U-187mV/ I-0.09uA

Day5.- U-149mV/ I-0.08uA 

The electrodes received the same polarity with which I pulsed them. Unfortunately, I don't know how it was before HV pulses, I will test this again in more detail.. Anyway, it can be seen that even if nothing is done with the cell, the values ​​slowly decrease.. 

Now some more data from the scope on the first day. The probe 1x (1MOhm), DCmode. I left it connected for almost 20min as a load and monitored the voltage. Here are the screens.. (ignore the drops, bad connection)

PEGcell 1MOhm load

PEGcell 1MOhm load 2

The voltage slowly, linearly, decreases (the scope shows less voltage than the multimeter because the probe is 1x/1MOhm).

Then I switched the probe to 10x (10MOhm) and again monitored the voltage for some time. 

PEGcell 10MOhm load

The voltage seemed more or less constant during this time. The small peeks and fluctuations are caused by noise (especially the mains 50Hz gets almost everywhere), but I'll come back to that later. 

Reaction after short circuit-

PEGcell reaction after short circuit

Nothing unusual here.

And finally, the legendary kickback Here in ACmod -

PEGcell kickback AC

I gave the cell pulses of opposite polarity with an AA battery (+ to -,- to +). Here again, even in DC mode!

PEGcell kickback AC and DC

As you can see there is no kickback in reality. In DCmod (white), we see that the voltage changed to the value U=Ucell-Ubat for a moment, then increased again to the Ucell voltage. No kickback. This can be seen in AC mode because in AC mode there is a decoupling capacitor inside the scope in the signal path. With these pulse lengths (made by hand), the scope only sees the initial change and inversion of the voltage - a negative spike (Ubat>Ucell, Ucell-Ubat is negative), and then it sees the voltage jump back to the positive level of the cell - a positive spike. With any two voltage sources you can create this waveform on the scope in ACmod. So no unique property of PEG.

A few more photos from the measurements on Day 7 (I forgot the 6th day)

I have a lot more data, but this writing is taking more time than I expected. I found out something interesting but I still need to test it better. I will gradually post more..

 

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AbitAnnoying posted this 13 August 2024

Hello, so I want to share with you my experiments with PEG cell. 

My current main cell.

PEGcell C-C PEGcell C-C

Construction -Electrodes are burnt and properly cleaned carbon rods from A batteries (ordinary large Zn/C cells). Electrolyte pure PEG8000. I covered the electrodes with melted PEG. I previously let the molten PEG stand in an open container for about 20 minutes at about 90°C (194°F) to evaporate some moisture, but it certainly wasn't enough to dry completely. But I honestly have no idea how much moisture is in it. When PEG cools it shrinks. To prevent cavities from forming, I added melted PEG several times during cooling.

From pouring to complete solidification, I applied high voltage pulses to the electrodes. The source was a small HV source (4.55kV/95uA) which charged 2 capacitors (2x680pF/6kV in parallel) via a potentiometer (3-16MOhm, to regulate the frequency of pulses) and these were then discharged through the spark gap (at about 3kV) into the cell. I don't know the frequency of the pulses, it could have been tens to hundreds of Hz. I don't have a photo of the process, I didn't take many photos of these beginnings, the values ​​are mostly on paper, sorry. (

HV pulz source

caps

HVsource

Unfortunately, I didn't measure the voltage and current before the HV pulse process (I regret it now). Here is the voltage and current of the cell after applying HV pulses and some time after (Measured with a 10MOhm multimeter) -

Day1.- Immediately afterwards U-1.8V / I-1.35uA

           Voltage after short circuit when measuring current U-1.56V

           Another longer current measurement (10s short circuit) I-1.2uA stable for 10s 

The first day I also watched the cell on the oscilloscope, I will describe below.

Then I just measured voltage and current for a few days.

Day2.- U-415mV / I-0.21uA

Day3.- U-246mV / I-0.14uA

Day4.- U-187mV/ I-0.09uA

Day5.- U-149mV/ I-0.08uA 

The electrodes received the same polarity with which I pulsed them. Unfortunately, I don't know how it was before HV pulses, I will test this again in more detail.. Anyway, it can be seen that even if nothing is done with the cell, the values ​​slowly decrease.. 

Now some more data from the scope on the first day. The probe 1x (1MOhm), DCmode. I left it connected for almost 20min as a load and monitored the voltage. Here are the screens.. (ignore the drops, bad connection)

PEGcell 1MOhm load

PEGcell 1MOhm load 2

The voltage slowly, linearly, decreases (the scope shows less voltage than the multimeter because the probe is 1x/1MOhm).

Then I switched the probe to 10x (10MOhm) and again monitored the voltage for some time. 

PEGcell 10MOhm load

The voltage seemed more or less constant during this time. The small peeks and fluctuations are caused by noise (especially the mains 50Hz gets almost everywhere), but I'll come back to that later. 

Reaction after short circuit-

PEGcell reaction after short circuit

Nothing unusual here.

And finally, the legendary kickback Here in ACmod -

PEGcell kickback AC

I gave the cell pulses of opposite polarity with an AA battery (+ to -,- to +). Here again, even in DC mode!

PEGcell kickback AC and DC

As you can see there is no kickback in reality. In DCmod (white), we see that the voltage changed to the value U=Ucell-Ubat for a moment, then increased again to the Ucell voltage. No kickback. This can be seen in AC mode because in AC mode there is a decoupling capacitor inside the scope in the signal path. With these pulse lengths (made by hand), the scope only sees the initial change and inversion of the voltage - a negative spike (Ubat>Ucell, Ucell-Ubat is negative), and then it sees the voltage jump back to the positive level of the cell - a positive spike. With any two voltage sources you can create this waveform on the scope in ACmod. So no unique property of PEG.

A few more photos from the measurements on Day 7 (I forgot the 6th day)

I have a lot more data, but this writing is taking more time than I expected. I found out something interesting but I still need to test it better. I will gradually post more..

 

AbitAnnoying posted this 14 August 2024

Hi. I would also like to mention my very first PEG cell. Sorry again, I almost didn't document the process here, I just tried what I saw in the videos .I'm only talking about it because I've already disassembled it, and I have a photos...


So a brief description - Aluminum and copper (cuprexit for PCB) electrodes. The surface in contact with the PEG was properly cleaned before, only the protruding edge was not cleaned completely. I roughened the surface a bit with coarse sandpaper. PEG8000 electrolyte. Pour the electrolyte between the electrodes in a molten state (without added water).
From pouring to solidification, HV pulses were applied in the same way as I have already described.
Values ​​of U and I-
Immediately after pouring before HV pulses - U-250mV / I-0.1uA (at the limit of sensitivity of the multimeter)
After HV pulses         U- 1.251V / I-0.53uA
After a few minutes   U-1.235V (I didn't measure the current here)
The voltage was still slowly dropping.
Well, and then I tried everything I could think of, other HV pulses, DC high voltage (same source) directly, I measured the current flowing through the cell with 30V connected and left it short-circuited overnight. I didn't even write any of this down, I just tried it..
That was 2 days, then it just sat on the table for 16 days. After 18 days, I took it apart.

Discoloration was visible on the copper electrode. Small dark spots all over the surface. Two significant stains. The stain closer to the hole is where a gap was formed during solidification. The copper still had a thin layer of PEG there. I think that during the application of HV, ozone was formed there, which then caused it.


No air gap was visible at the location of the second stain. I think that's where the electrodes were closest to each other (one plate was very slightly bent in the corner). Unfortunately, I didn't check it (I immediately recycled everything for the next cell). There is also a small protrusion in the copper right at the edge, a possible cause..


There were no visible changes on the aluminum electrode except for small dark spots as on the copper.

There were no visible changes on the peg.

Cu side-

Al side-

The small spots at first looked like stuck PEG residues, they were there too, but underneath were spots that were not easy to sand off. The two large spots on the copper went down pretty easily.

I will also mention that the PEG stuck to the copper very well, but the aluminum was released with minimal force.
Since I'm not a chemist, I don't have an exact explanation for this. My theory is that it was caused by HV, or it is a reaction caused by the potential difference (or causing the potential difference). We'll see with other cells. I will try to document everything better.

Fighter posted this 14 August 2024

Hi,

Very interesting experiments and data, thank you for sharing !

Certainly different than what I presented.

I would say the voltage should be much higher, from a few hundreds of mV to about 1.4 V like I presented with my cells.

Based on what I observed in my experiments I would try a few things for your next generation of cells.

Try to build the solution with watter like I did. I understand the reason why you use melting PEG (to make sure there is no watter) but what if melting and cooling PEG doesn't result in the same crystaline structure like it happens with watter ? 

I know Joel also used PEG melting and high-voltage conditioning but he is using a different PEG product than we have available in Europe. Maybe what we have available is not working well with these methods.

Also try carbon felt with magnesium. From my experiments that seems to be the most efficient combination (as I presented here).

Yes, having the electrodes made from the same material is demonstrating these cells are not using the usual galvanic process (I also have a cell with electrodes made from the same material - aluminum tinfoil) but that's the less efficient combination (small voltage).

About conditioning, I only used short conditioning periods (~ 5 minutes from time to time) with my two first generation cells when they were dry enough to not have electrical conduction through PEG.

And I used 30 V, not high voltage. Maybe the markings you see on the electrodes are the result of micro-spikes between them ? I'm asking this because I didn't noticed any corrosion effects (or color changes) on the electrodes of my cells.

About the voltage dropping, that's normal for a while but at some point the voltage is stabilized, usually after a few weeks in my case. And the drop should not be that high, in my experiments it was about 100-200 mV.

I would also try with Effecol 3350 by Epsilon Health as I used, it should be available everywhere in Europe (I guess...).

That's what I would do based on the observations I've made in my experiments.

Don't get me wrong, this is research and in research there is no right or wrong approach, all the possible approaches must be explored.

Again, very interesting experiments, thanks for sharing !

Regards,

Fighter

"If you want to find the secrets of the universe, think in terms of energy, frequency and vibration."
Nikola Tesla
AbitAnnoying posted this 16 August 2024

Yes, I also think it was probably caused by HV. I will use a lower voltage now.. I will try to build one Cell the same as yours (probably Al-Al) in the same way so we can compare the voltage between different PEGs. I'm quite curious about that. But now I have 1 kg of PEG8000 and I don't really want to buy more Maybe I'll buy magnesium and carbon felt someday. I will try adding water. But now I would mainly like to find out how the voltage between the same electrodes is created, what determines which electrode will be positive and which will be negative. I tried applying 6V in reverse polarity to the C-C PEGcell for a few minutes and it reversed the polarity of the cell for quite some time. The next day the polarity was reversed again (as before the experiment). I will write the details later. I am now also trying the circuit according to "Jagau's ferrite at work" and I want to try SEC. So now it will be slower with PEGcell

AbitAnnoying posted this 17 August 2024

Hello. Another experiment, the dependence of voltage on temperature. The can not only serves as a temperature chamber but also as a shield (is connected to ground). At voltage values ​​in the low mV range, ambient noise can greatly affect the measurement. In the future, I have to think better of the heating to reach a higher temperature.
Setup-
C-C PEG cell. Can heated by heater. Measured with scope, probe 10x. Now I noticed that I had the wrong probe set to 1x in the scope! So multiply the displayed voltage values ​​by x10!

The results (bottom line is zero, 20mV/div!!)-

1

So the voltage rise with temperature is approximately 36mV/40°C (36mV/75°F). Unfortunately, the can doesn't shield perfectly and some noise gets in, those sine-like little mounds are caused by 50Hz noise. Here is the noise that gets inside (10mV/div!!) -

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AbitAnnoying posted this 17 August 2024

Test of the generation of voltage on the same electrodes and their polarization.

I found some gold plated contacts of sufficient size. I'm not sure about the thickness of the gilding though, it doesn't look very thick. But better than nothing I made each electrode from two connected contacts. Electrolyte melted PEG8000 (I added a few drops of distilled water).

I didn't know what to expect, so I put 200mV/div, but that was too much, unfortunately now it's hard to see what was actually happening. But it still says something. Bandwidth limited to 20MHz. That's why Bw is at the value of volts/div. Noise then affects the measurement less. But it is still quite noticeable at high sensitivity despite all the shielding. DCmod of course.

Probe 10x. Here are the screenshots (please note the different values/div between screens) -

After the initial measurement (the top is protected by a piece of paper when it is wrapped in foil, one electrode is also insulated with kapton tape, it is no longer visible here because I was replacing the wires with coax.)

You can see some initial noise as the PEG slowly flows between the electrodes, then the electrodes polarize and the voltage suddenly jumps and starts to drop. Then there are small fluctuations where finally the voltage reaches about 20mV and then just drops to almost zero. Fluctuations can be caused by ambient noise. I don't think it's a coincidence that the electrode that was connected to the ground (through the scope) became positive. It would also like to measure it with an isolated oscilloscope, so that what is connected is not grounded. See what kind of polarization this produces. I don't have that option, but I can try with a multimeter. I will repeat the experiments again, I have to measure it better. There remained a small voltage, which then slowly rose again, too small to be clearly visible on the scope. 

After a few minutes-

I will continue today..

AbitAnnoying posted this 30 August 2024

Here's more, better, data from the experiment. Everything was the same except I put the scop ground on the other electrode. The polarity of the electrodes is the same as in the first experiment, although the ground electrode was different than last time. So it was obviously not a coincidence, but for a different reason than I thought. Now I think the gold plating is really very thin, and one of the electrodes simply has more exposed underlying metal. That will determine the polarity. They looked a bit oxidized when I found them.. But still, it's interesting to see how the cell voltage behaves in the first moments after the two materials come into contact. Interestingly there are 2 peaks, one at the beginning when the PEG is at it's highest temperature (also when topped up there is a peak) and then later on the voltage still slowly rises and falls again. But this time not to zero, but stayed at 10mV. I may have removed more gold plating during the cleaning process after the first attempt, otherwise I don't know why. But it can be seen that there is a certain optimum temperature when the PEG is already stiff and the voltage is the highest (I don't know at what temperature it was, I'll probably add it to the list of reasons to get some thermal imaging camera ). And the other interesting temperature seems to be when the PEG is liquid and hot, I'll try this one out. 

I try to shield everything, otherwise nothing would be visible due to the 50Hz noise. This is what it looks like when nothing is connected to the probe..

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