Li-ion cells cycle ageing

[Pajda]

I have some new data from cycling. Panasonic PF at 250 cycles keeps trend both in capacity decreasing and DCIR rise. LG M36 continue with very slow capacity decline. M36 DCIR got reverse trend, at 250 cycles is lower than 150 and 200 cycles. Can´t exclude my measuring error, trying to find out what is happening. Sanyo GA capacity decreasing trend continue, however DCIR rise stopped.

I was thinking that its a time for the new 50 cycles (for some of us it is like waiting for new episode of a good serial).

My comments are: Do not worry about DCIR fluctuations, it is still in cca 5% error range which is excelent result for the electrochemical cell. I was telling you that I admire that you are still performing precision measurement on very unstable process :wink: We old pals are just following the trend of growth or more expressively a White fang pisses on some fluctuation. So do not worry the GA will continue with DCIR rise trend course where the M36 stay still. 8)

Unfortunately thanks to today´s dropout of the ZKETECH control software I lost lot of Samsung 29E last batch data (cca 36 cycles) and also some Panasonic PF and Sanyo GA data. At least I measured PF DCIR and continue cycling. PF keeps DCIR still the same around 29,3 miliohm.

I was wondering what has happened? It was a "Comm Error" issue? I suppose that you know that EBX software automatically saves running data into its folder (.bk1 = .dat and .bk0 = .run files) and so after the software crashes you can in most cases continue in measurement without significant loss of data? After the crash just start a new EBX Software instance (i usually also restart the PC), then connect to the tester and then click right mouse on some channel and choose "Channel or device continue". Your EBX tester must be on the same comm port as before crash. EB Software for single channel testers does not have this function.

 

[docware]

I was wondering what has happened? It was a "Comm Error" issue? I suppose that you know that EBX software automatically saves running data into its folder (.dat and .run files) and so after the software crashes you can in most cases continue in measurement without significant loss of data? After the crash just start a new EBX Software instance (i usually also restart the PC), then connect to the tester and then click right mouse on some channel and choose "Channel or device continue". Your EBX tester must be on the same comm port as before crash. EB Software for single channel testers does not have this function.

After some analyzing I have to say that it was my stupidity. During tapping on the not responding touch pad (dry fingers ?) I probably minimized EBX soft (not realizing it), which of course disappeared from the screen. Trying to find it again by switching alt + tab was not successful. So I was opening new EBX soft and trying to connect it but unsuccessfuly. During restart I met question „Close the software ? „ and confirm that (mistake). Not able to connect EBX soft after restart, had to change the port. I have AutoSafe function still on, yet data was lost, ZKETECH data showing lot of 0 kb files.
I regret it, was really wondering how 29E is doing.

 

[flippy]

After some analyzing I have to say that it was my stupidity. During tapping on the not responding touch pad (dry fingers ?) I probably minimized EBX soft (not realizing it), which of course disappeared from the screen. Trying to find it again by switching alt + tab was not successful. So I was opening new EBX soft and trying to connect it but unsuccessfuly. During restart I met question „Close the software ? „ and confirm that (mistake). Not able to connect EBX soft after restart, had to change the port. I have AutoSafe function still on, yet data was lost, ZKETECH data showing lot of 0 kb files.
I regret it, was really wondering how 29E is doing.

i still have a couple of raw 29E test files of up to 500 cycles if you want that to play with

once i am into my new workshop (upgrade yeah) i will set up the whole setup with a dedicated pc and UPS behind it so it can run 24/7 without any breaks and then trow in 8 29E's and run them until they are dead.

 

[docware]

Of course yes flippy, show us your data for comparison.

 

[flippy]

right now i am moving house, so once i dig out the pc that has the data i will send you the raw files for you to play with as you need the matching software to use the files.

in the meantime i will start a new run and really try to kill the cells.

 

[docware]

Oh no, raw data no, I am oversaturated with raw data. :x
I was (and I am) hoping you show us also some graphic results please.

 

[flippy]

Oh no, raw data no, I am oversaturated with raw data. :x
I was (and I am) hoping you show us also some graphic results please.

why should i not share the pain of digging into raw data for hours? :lol:

 

[brone]

If the raw data is a text format (can be readable with notepad), I can make a parser to get a chart from the data

 

[flippy]

If the raw data is a text format (can be readable with notepad), I can make a parser to get a chart from the data

docware and i use specialized pieces of kit with their own software.

 

[Pajda]

After some analyzing I have to say that it was my stupidity. During tapping on the not responding touch pad (dry fingers ?) I probably minimized EBX soft (not realizing it), which of course disappeared from the screen. Trying to find it again by switching alt + tab was not successful. So I was opening new EBX soft and trying to connect it but unsuccessfuly. During restart I met question „Close the software ? „ and confirm that (mistake). Not able to connect EBX soft after restart, had to change the port. I have AutoSafe function still on, yet data was lost, ZKETECH data showing lot of 0 kb files.
I regret it, was really wondering how 29E is doing.

No it was not. This is well known "feature" of EB(X) software, it sometimes did not minimize to the tray, but to the "hidden icon menu" and if you are not familiar with this behavior, it leads to the situation you described.

The next "feature" is the random loss of connection, particularly when you are running couple of testers on the same bus. Fortunately it can be solved without losing the data.

Also when you are running tester on slower PC, there is sometimes problem when you are trying to save data, particularly from longer measurements (>5MB files) from the menu with function "channel save". Occasionally happens that all channels falls to the "wait" state during this saving operation. This is reason why I do not use "channel/device save" function and I am working only with autosaved data.

 

[docware]

Hmm, doesn´t sound very well. Thank you for this info.

 

[flippy]

Also when you are running tester on slower PC, there is sometimes problem when you are trying to save data, particularly from longer measurements (>5MB files) from the menu with function "save data". Occasionally happens that all channels falls to the "wait" state during this saving operation. This is reason why I do not use "save" function and I am working only with autosaved data.

this is why i usually work in 100~250 cycle runs.

 

[Pajda]

There is also one puny HW issue with EBC-X0510 and almost all other ZKETECH testers. Chinese engineers for some reason omitted to connect PE pin from the power inlet to the tester metal chassis. That means that tester is not comply with EU safety regulations (I think that even Chinese ones) for safety of electrical devices. :? It is easy to fix, there is not populated PE faston on the power inlet inside the case. So you need only few centimeters of PE color wire, crimping faston on the one side and the M3 cable lug on the other side and then install the cable lug under the nut which is fixing the power inlet. They used a high quality powder coating so it is better to use dremel tool or knife to remove the coating in this place. You can check this by continuity test between inlet PE pin and any screw head.

... when I think about it, I should have probably started with this message

 

[flippy]

bought mine 1,5~2 years ago and mine did have it sorted proper. it even has a shakeproof washer.

i have this weird thing where i use my testing stuff from being a electrician on all my gear i buy to weed out stuff like this.

 

[neptronix]

eMark, we've received a lot of moderation reports about your posts here, particularly the one where you promote a company's product and then accuse someone of shilling.
I deleted your promotional post and recommend you stay on topic and don't point fingers in a thread where people are just looking for help.

I know this discussion can get back in line.

Carry on folks.

 

[Dak77]

I do realize that this is one of the , if not THE go to forum for anything battery powered , but still the level of knowledge funneled in here is sometimes very humbling. Are most of you electrical engineers or industrial electricians?

 

[neptronix]

I do realize that this is one of the , if not THE go to forum for anything battery powered , but still the level of knowledge funneled in here is sometimes very humbling. Are most of you electrical engineers or industrial electricians?

This forum is a mixture of electrical engineers, mechanical engineers, hobbyists, and goofballs. Welcome 8)

What can we help you understand?

 

[Dak77]

I do realize that this is one of the , if not THE go to forum for anything battery powered , but still the level of knowledge funneled in here is sometimes very humbling. Are most of you electrical engineers or industrial electricians?

This forum is a mixture of electrical engineers, mechanical engineers, hobbyists, and goofballs. Welcome 8)

What can we help you understand?

Life. lol. Thanks for your response. It's really really nice for a forum to exist that you can get high level feedback and help from people for basically nothing but gratitude in return. Awesome "place" for sure. Thank you all . I don't think a lot of folks understand how much this kind of support is worth .

 

[neptronix]

I appreciate comments like that, thanks

Enjoy!

 

[eMark]

Not able to connect EBX soft after restart, had to change the port. I have AutoSafe function still on, yet data was lost, ZKETECH data showing lot of 0 kb files.
I regret it, was really wondering how 29E is doing.

We all can relate to technology gliches, so don't fret as we appreciate your steadfastness and determination.

Oh no, raw data no, I am oversaturated with raw data. :x
I was (and I am) hoping you show us also some graphic results please.

Don't envy your task ... well maybe flippy does (its meant to be a compliment)
Here's a couple posts from the previous thread that was the impetus for this thread ... sheds a little more light ...

But even LG can make a bad cells, LG MG1 was an epic fail at least the samples I have tested. Fortunately they recently replace it by excellent M29 cell which seems to outperform even Samsung 29E in almost all parameters including price. And also LG 21700 M50T cells have big troubles with cycle life (it is not as bad but it does not reach the quality of M36). On the other side, overall parameters of Samsung 50E is a big surprise for me and it is now the only choice in 21700 HE cells category.

So maybe to give MJ1 the benefit of doubt and another chance need to test it again (just a suggestion).

My favourite GA doesn´t do very well.

Do we need to test GA again (another fresh cell) with so many Sanyo fans of the GA as a most energetic champ.
Here's a comparative thread that is more to our liking with respect to the Sanyo GA cell ...
https://electricbike.com/forum/forum/batteries/18650/52414-3500mah-league-sanyo-ncr18650ga-panasonic-ncr18650ga-lg-mj1-samsung-inr18650-35e ... is it possible the Sanyo GA is slipping from when tested in 2017 (Heaven forbid).

Would be interested what doc, Pajda, flippy think of this 2017 test as being accurately representative of these Energetic Contenders in 2017 ?

 

[Pajda]

eMark you are acting as a small kid which wants a new toy. I am saying that because you do not understand the factual explanation which I give you in this topic. It is your business if you would like to present yourself like that, but your approach only insults docware and his great work for community.

So if you would like to know results of 30Q and MJ1 cycle life test right know, then read again my posts on this forum and read it carefully!!!! Or you must wait here for ca three months until docware finished already running tests, only then he can add another cells for testing.

You have quoted one of my post where I am talking about LG MG1, especially for you once again MG1, not MJ1!!! If one thinks that it should be a typo, then one can google it and find that MG1 is an existing cell with "2900mAh" capacity. And if it is not enough then one should use a common sense "Why the heck this guy is talking about replacing the "3500mAh" cell (MJ1) with the cell with "2900mAh" capacity (M29) ???" Isn't the problem that he doesn't talk about MJ1?

The cycle life test results of GA measured by docware are valid. I got the similar results on more than dozen samples from different batches. So if you do not believe them, why are you asking for other cell test results?

 

[john61ct]

I still think putting in any more "requests / suggestions" to y'all at this point is a bit over the top.

At least his "tone of voice" is improving.

 

[neptronix]

Padja

Let's keep it on point and without personal insults please.

 

[Pajda]

neptronix: First of all someone might consider as a personal insult to hurt his nick, particularly when it is only 5 letters long. :? Does "Padja" mean something in english?

I knew that my reaction to eMark would turn out exactly that way, I responded to him here only because of his spam via PM, and particularly by his last post, where he basically said he did not consider the results presented here to be valid, because "They say so that Sanyo GA must be just perfect". And this was beyond the line for me.

At least in my country we consider as normal question: "Hey guys, I am interested in 30Q nad MJ1 cells, did you already test them or you are considering to test them in future, I would love to know their results?" You can check how eMark formulated his question (at least for me it was not formatted as a question but rather demand). But even then we all clearly answered him that I am already tested both of this cells and my comment to the results can be found on this forum. Also that docware does not have the capacity to add another cells to his tests before he finished this batch.

And neptronix if you would like to know another example of childish reaction, Then I can erase all of my posts here on this forum and stop answering the questions here. But I feel adult that i will not to acting like that.

 

[Jan-Erik-86]

So maybe to give MJ1 the benefit of doubt and another chance need to test it again (just a suggestion).

He was talking about the MG1, not MJ1. These are two very different cells and must not be mixed up.
MJ1 have already been tested and turned out to be a very good cell. From what i understood, the M36 is equally good as MJ1 at lower charge/discharge rates, but when you increase the charge/discharge rates the M36 suffers badly while the MJ1 keeps on going.

Do we need to test GA again (another fresh cell) with so many Sanyo fans of the GA as a most energetic champ.
Here's a comparative thread that is more to our liking with respect to the Sanyo GA cell ...
https://electricbike.com/forum/forum/batteries/18650/52414-3500mah-league-sanyo-ncr18650ga-panasonic-ncr18650ga-lg-mj1-samsung-inr18650-35e ... is it possible the Sanyo GA is slipping from when tested in 2017 (Heaven forbid).

Would be interested what doc, Pajda, flippy think of this 2017 test as being accurately representative of these Energetic Contenders in 2017 ?

Simply the fact that you ask this about the GA, makes it clear that it needs to be tested by more people, yes.

Please note that the test you are linking to is only testing how the cell performs while new. There are no doubts the cell performs excellent when brand new. It's not that the GA is any different today then in 2017, but it's when the GA is ageing that it starts to suffer a bit more then others. For sure it's a good quality cell, but there are better lasting alternatives.

I'm the one who originally started the thread linked to in the 1st post, as i was considering the GA or VTC6 for my new pack, but along the way i learned there were better options then the GA, (MJ1 or M36). The 29E and PF was also claimed to be a better option by some (but others did not agree). I believe this was the root cause for why Doc took the time and effort to actually start a long term test of these specific cells that we're now starting to see the results from.