Can anyone confirm what production date these CATL SE cells are?

[Luk88]

I've got few catl cells that Im trying to assess quality off, but I'm having trouble decoding their numbers attached. Can anyone help please?

I doubt they traveled from the future year 2029, also they measure surprisingly good internal resistance (ac so far) to be 4 years old..


I found the old threads about it, but the numbers make no sense based on that.

Edit: also there is big probability the numbers are fake as all cells have the same numbers

Finally, they measure the following (spec is under 0.5mohm)
4 * 0.35 milliohm
2 * 0.25 milliohm
1 0.40 milliohm
1 0.49 milliohm

DC internal resistance seems good. I've yet to measure capacity. Is such AC IR discrepancy a very bad sign? The cells were good price, but not super cheap

One more thing. 2 of these 0.35mOhm have a slight one sided bulge...

 

[Luk88]

After careful checking turns out 5 of my cells are bulged (most 3~5mm, but one about 6mm) and the most worrying one more has a crack running down the side. I thought I could smell the electrolyte when I opened the box, but the smell quickly dissapeared. I don't think pouches are damaged, but sure as hell I'm not charging that one.

So 6 bad ones in a batch of 8. Not good.

 

[Alarchist]

Is this another one of your find the cheapest seller possible and hope for the best purchases?

 

[Luk88]

Is this another one of your find the cheapest seller possible and hope for the best purchases?

Actually no, it is one of my "find the only seller that has stock in Europe for smaller cells and doesn't charge 2x for this and hope for the best" purchase...


Also I bought 16 280ah cells from the same guy. Other than being a year old, they are in great, unused condition.

If I bought this substantially below the usual price I'd have mentioned it like in my battery thread.