I ended up stripping the top layer and welded button top off of ALL of my 30Qs from batches 136 and 141(multiple sellers for both batches)
All were 3 leg, all had proper lot codes except for my most recent liionwholesale batch, all measured similar IR on my MiBoxer C412. I dont have any special load testers, but they seem to be ok.
Regardless, im done with the 30q. Ill be doing VT6s with solder blobs the next time around.
Do any of the ones you’ve acquired have the writing on the can under the wrap (especially the one with batch 136)?
I have a couple of 30Qs bought from ebay.au (not techaroundyou though) that seem mostly OK but I have had doubts. They have 3-prong top caps that look identical other Samsung flat tops, and the writing on the wrap shows no variation in typography of the kind that others have reported. They are marked batch 136 like other 30Qs. When new they tested slightly lower capacity than other 30Qs (maybe 7-8% down) but their internal resistance was very similar to other flat-top 30Qs. They seem to deliver good current in use, but that is a subjective assessment and not tested. My main concern has been the absence of writing on the can inside the wrap, like on other Samsungs.
Capacity and resistance testing done on an Opus BT-C3100. My capacity measurements are usually about 3% higher than HKJ’s at the same current draw (done at 1000mA). I have found that resistance measurement on the Opus is much more consistent and closer to those reported by HKJ if I maintain firm pressure on the slide against the back of the cell.
So my question is: is the absence of writing on the cans inside the wrap significant?
andygs, unwrapping at least one of your eBay bought 30Q button tops can shed some definitive light.
This is the sort of cell can markings Samsung 30Q 29E O:) cells come printed with:
Sooner or later you should buy some heat shrinkable sleeves/wraps and learn to wrap batteries anyway, imho.
Tue, 05/19/2020 - 13:47
Does the batch 136 cell you got from techaroundyou have the code printed on the metal can under the wrap?
Select reputable wholesalers to purchase
Then we also have Ali express store, selling genuine 30q batteries 
From Barkuti’s pic: is this genuine Samsung 30Q?
markings:
E9GG
B4C31
the 2nd digit of the first line “9” from “E9GG” should be a “0” for Samsung 30Q, as per my understanding.
(eg. L0I7, L0J4, where the 2nd digit is “0” for 30Q)
The same question applies to the two other cells depicted by Barkuti. Neither of them has the two lines printed across the cell with “0” as the second character on the first line.
On the other hand, I have a bunch of Samsung 20Q cells from Aldi power tools. They have marking across the cell in two lines C0HV / N6D81. That is a zero for the second character on the first line. As 20Qs they have only 70% of the capacity expected of a 30Q.
It is fake 30Q， this is samsung 29E， E9GG，July 2016
These are multiple shots of the same cell.
Good catch and good to know, along with another one I received it in some old early AE order :facepalm: long ago but didn't actually internal resistance tested them; I just presumed what they were with the limited information I had.
I have a 30Q from NKON which I'll shoot and rewrap for a better picture.
A quick look learned that all (28) my 30Q cell’s are marked 136. Bought them from BG and NKON.
Pictures of an actual 30Q (first picture is before rewrapping):
So well, that actually is my only 30Q right now. Time to blow the dust off some VTC5As…
Just for the record, Liionwholesale claims that some recent batches of the 30Q might have weird can markings due to temporary production facility changes. I have a few marked making me think they were 29E’s as well but they have similar IR and capacity to my known legit 30Qs with good can markings.
Sooooo I just realized my two latest batches from Lucky’s Electronics Store on AliExpress sent me 30Qs with the top line of code “L30Q” . This has been my trusted supplier for the last 4 years and is listed on BLF as a trusted source.
I’m just charging a couple up to do a discharge test on my CBA.
I had 100pcs with an added button top arrive genuine but looks like my flat top are fakes.
Genuine always test at 3.40v and these read 3.44v.
.
EDIT: Well, they’re genuine. Tested at 15A and got 2968mAh and it almost perfectly matches the curve of Mooch’s test back in 2018
Just starting fairly recently, I’ve started to record measurements of batteries (from shipped condition: voltage & IR as tested with YR1030 resistance tester, and weight; I haven’t started doing measuring dimensions though).
So far the genuine 30Qs I get arrive usually from around 3.36v-3.45v. and there seem to be 2 sets of IR readings, I think both are genuine.
1 set of 30Qs (“141”) have YR1030 IR reading of around 11.8-12.0mOhms, while the others (“136” and “138”) usually around 12.6-12.8mOhms.
I have the same resistance tester as you and two cells with L30Q read 12.06 & 12.11. It’s very interesting that these are genuine when Mooch said if it hasn’t got “0” as the 2nd digit it’s fake
My weird marking 30Qs have that same “L30Q” code too.
I messaged Mooch and he said it could be new codes that Samsung is starting to use. The 40T is no longer a 0 for the 2nd digit. It’s now N40T
Mooch is going to try find a L30Q and test it.
I might be too late … but, how about “R30Q” code?
One online shop in my country has a good deal of 30Q (around $4.5 per piece). But the close-up picture shows a faint code R30Q/JCKA6 (I think). It is neither “0” at the 2nd position nor “L30Q”. In addition, some VTC6 pics in this shop show LiitoKala sticker on the cell (I heard a lot of fakes in Liito store).
I’m not sure whether to buy from this shop or not. I also don’t have tools for testing, so buying and testing it is not possible now.
Additional reference, this is the picture of markings on pink wrap.
R30Q is genuine, all mine come from a trusted source and I’ve tested them as authentic. This code alone doesn’t make them genuine though.
The warning note is on all new batches now
$4.50 a pc sounds pretty cheap though but if he’s buying in massive bulk then they’d get a better discount than me. My cost price is $4.40 usd excl shipping.
I’d be cautious on the pricing