Help me troubleshoot this pack please. How are these voltages?

[999zip999]

https://images.app.goo.gl/AjF1zRK1BQgxYyNt9. Be yea cellog is discontinue. Una chargers is dead ?
https://www.rcnhobby.com/unrc-un-a6-plus-una6-1s-6s-lipo-battery-pro-8a-balance-charger.html
You should find it cheaper.

 

[eikido]

I'm having issues finding the bad cell(s).

Here is a video:
https://www.youtube.com/watch?v=pVJT2L6f1Vg

I load the battery pack and monitor two cell groups. The bad cell group 11 (which is actually group 3) and some random one.
It is very clear that cell group 3 (11) is going out of balance when loaded.

I harvested the cells and did a capacity test on all with my liitokala Lii-500s but couldn't notice something obvious.

I did discover one thing but could it be that cell?`

My Lii-500s can display the charge and discharge capacity:

Cell 1: Discharge: 2872 ; Charge: 2832
Cell 2: Discharge: 2890 ; Charge: 2741
Cell 3: Discharge: 2830 ; Charge: 2836
Cell 4: Discharge: 2903 ; Charge: 2910
Cell 5: Discharge: 2781 ; Charge: 2858
Cell 6: Discharge: 2695 ; Charge: 2955

Could it by any chance be an issue with cell 6?


Edit: I measured Cell 6, 3.2V, put it in the charger and set it to discharge at 500mA and it dropped very quickly (less than a minut) to 3.02v. After three minutes down to 2.9v. Took it out, measured about 3.05v, after 30 minutes, 3.15v.

 

[docware]

Eikido, it seems to me that your effort to build battery from noname chinese cells is wasting of money and time.

 

[eikido]

Eikido, it seems to me that your effort to build battery from noname chinese cells is wasting of money and time.

I'm not building it, i'm troubleshooting it for a friend.
It's a great way to learn.
Everybody starts from 0.

 

[docware]

Well, this lesson brings advice : don´t waste your time with noname chinese cells and throw them to the hazardous scrap.

 

[eikido]

Well, this lesson brings advice : don´t waste your time with noname chinese cells and throw them to the hazardous scrap.

Are you in a bad mood?
Please don't take it out on me.

 

[john61ct]

I do not perceive any hostility there.

He is giving you helpful advice.

But you can choose to delay following it, for the sake of your learning

 

[eikido]

It's ok, i will try myself.
I'm not expecting any help, i only appreciate any help i get.
I'm learning and i think this is the best way to learn. I wouldn't do the same on a big pack with loads of MJ1's.

And sincpower is also not all that bad.
http://www.sincbattery.org/index.html

 

[john61ct]

And sincpower is also not all that bad.
http://www.sincbattery.org/index.html

What evidence do you have for that statement?

 

[eikido]

And sincpower is also not all that bad.
http://www.sincbattery.org/index.html

What evidence do you have for that statement?

They are in many ebikes and scooters and have been around for many years and they don't try to hide their brand like other fake chinese factories.
But yes, i haven't seen any proper tests on those cells.

 

[john61ct]

LOL spammer

totally untrustworthy to recommend a vendor when you obviously work for them, nice try