Hi sixty545. I’m fighting a virus right now and my thinking is very fuzzy right now, I can’t seem to make sense of what you have reported. I’ll reread your post tomorrow when I hopefully feel better. Thanks for taking interest in this matter. It will be great to be able to determine date of manufacture for these types of cells.
I see the code that you mentioned. It’s a bit faint, but can seem through the wrapper. One of my 30q cells has the following label near the positive end:
JOF8
67FC1
A little lower, it says:
1CD2
1CD2
EDIT: Fixed numerous typos for like the 4th time.
EDIT2: I think I follow you now. I think you’re saying that the last 2 digits of the first marking on the can is the date code with the 3rd digit being year and the 4th month as follows:
3rd Digit:
A = 2010
B = 2011
C = 2012
D = 2013
E = 2014
F = 2015
4th Digit:
1 = Jan
2 = Feb
3 = Mar
4 = Apr
5 = May
6 = Jun
7 = Jul
8 = Aug
9 = Sep
A = Oct
B = Nov
C = Dec
Exactly! My post can not be read alone but together with the previous to fully understand, I think. It was also meant as a little happening. And I did not want to go into day of month (to keep it simple).
The first two lines are directly below each other, the third line (4 digits) is further down and usually somewhere else around the circumference of the cell.
I’ve previously got a few “Samsung INR18650-30Q” which I suspect were not genuine 30Q. However they look very similar to the real Samsung 30Q, and capacity test seems to be similar (around 2800+mAh, where genuine 30Q have around 2900+mAh on capacity discharge test).
The AC IR (using YR1030 resistance tester) of genuine 30Q appears to be around 11.8mOhms (those marked “141”) and around 12.6mOhms (those marked “136”), at least on the samples of 30Q that I have.
The AC IR (YR1030) of the “non-genuine” 30Q are around 21mOhms, which is far from the ~12mOhms of the genuine 30Q.
On checking the “date” code underneath the wrapper. I notice the genuine 30Q “141” or “136” have something like L0J4 or L0I1.
As per the above decoding information
“2nd digit: Final number of Model Name (“0” is INR18650-30x)”
So they are “0” = 30Q.
But on the non-genuine 30Q, I see that they read “E9G0” or “E9HJ” (G = 2016, H = 2017), but “9” would then refer to ‘final number of model name’, does this mean the Samsung INR18650-29E?
So maybe these non-genuine 30Q are probably real Samsung INR18650-29E instead?
(on a side note: I also checked the underlying code for Samsung 25R, and they have “5” in the 2nd-digit).
Does anyone know what is supposed to be the AC IR (using YR1030 or similar resistance meter) of a genuine Samsung INR18650-29E?
I had something similar happen to me a few weeks ago(Samsung INR18650-30Q Questionable markings from trusted seller.), but I have no reliable/accurate way of testing. I only have a MiBoxer C412. The questionable button top cells have a similar IR to the “known good L0XX” button tops I have in my Q8 from a few years ago.
The questionable cells were bought from Liionwholesale and they claim it was because Samsung had to move production around that the lot/date codes were not consistent last year.
Typical ACIR of 30Q is about 12 miliohm, typical ACIR of 29E7 is about 21 miliohm, measured with YR1030 at 25 °C.
Typical capacity of 30Q is about 3 030 mAh, typical capacity of 29E7 is about 2 800 mAh, both at 1 A discharge / 25 °C.
I found some additional info about Samsung date codes here:
(most are already mentioned above, but there’s mention of “older” Samsung date codes in the link below)
The above blog/link didn’t have date code identification info for LG or Molicell though.
(BatteryBro date code site can decode LG date codes. But I notice some new LG cells have an additional letter in front, so like
an older LG may have a label ‘Q364L301A1’ — BatteryBro date code site: enter “Q364” for it to decode the date.
on newer LG that has label ‘GT140E193A1’ — in BatteryBro date code site: remove the initial ‘G’ and enter ‘T140’ for it to decode the date.
can anyone help me with understanding the manufacturing date of this cell, and if it is even a Samsung orignal cell? I should be a Samsung Q20
Apparently is made in Samsung's Malaysia factory (SDIEM), and I have not been able to find specifications on the codes used by this factory - only the SDI ones. I have not found any pattern that fits with the codes on my cell, so I'm starting to doubt it's not original.
Here are the codes on the plastic wrap and on the cell itself (by order of height, from top to bottom on the cell):
I have a similar problem where I am unable to decipher the Month code. My 1st line on the can is E0JP, so not sure what the P means. The J means 2019, which seems right on mine. My cells are INR-18650-20R cells from a Ryobi 40v 4AH pack. I’m not overly concerned about month, but it would be nice to know.