Anyone else had dud Samsung 30Q "button tops" from BG recently ?

LED Flashlights – General Info
1

Don’t wan’t to over-react, but of x8 Samsung 30Q button tops, delivered from BangGood this week, I’ve found two duds.

I won’t go into details yet, but although seeming to charge fully, after a few seconds of very mild current draw in e.g. a 2-3A torch, they drop to undervoltage cutoff levels, about 3V, and barely recover afterwards, even open circuit.

I don’t think it is the aftermarket button additions, the cells seem to behave similarly to badly over-discharged ones that can hold barely a glimmer of charge.

Anyone else seen something similar ? Meanwhile those who have e.g. ordered a four-pack or two for e.g. a Q8, please take a look, you might not realise, if they go into e.g. a 4P torch.

Lets hope I am just a very very unlucky person.

2

Do you have a way to measure the internal resistance of the batteries, like an analyzing charger? Wonder if that is noticeably different on the duds. Analyzing chargers tend to be rather inaccurate on the IR measurements, but you should still be able to see the difference between, say, a 30Q and a NCR18650B.

I just had 12 of them arrive this week from BangGood, some of which were going to go into storage for a gift. I partially charged all of them (putting in ~1000 - 1500 mAh) and checked the internal resistance on my Zanflare C4 charger, thinking that would be enough to identify any fakes or duds. The internal resistance measurement on that charger isn’t super consistent, with considerable variance on repeat measurements of the same cell, but the variance in measurements of one cell is still small compared to the difference between the measurements of a 30Q and a random old 18650 I had laying around. So I would think that could pick up the difference between a normal cell and a faulty one.

But I guess I’ll have to get all of those batteries out and actually cycle them through lights just to be sure. Based on your description, any 1000 lumen light should be enough to test them, which should help speed up the process.

Thanks for the heads up about this, by the way. Will update with my results.

3

i too purchase 2x4 pack from banggood, charge test them, showing lower rating ~2700mah, used them in my mt07, otherwise no issues here yet.

4

I had a pack of 4 come in last week and they are all perfect.
All had a charge of 3.45V before charging.

5

Ok, I just did a quick test of the 12 30Qs I purchased. Had 4 lights, and ran them on their highest setting for 3-4 minutes, let the lights cool, and repeated the test. Checked voltage before and after, and they all came back as expected, with just a small voltage drop from the test. So none of mine appeared defective as in the OP.

Could try to run tests on them with my charger, but I didn’t want to end up with all of them at full capacity, as 8 are going to be stored for Christmas gifts. So I wanted to keep those around 50%. But I watched their voltage behavior as they charged, and the change after putting 1000 mAh in them indicates their capacities are at least in the ballpark.

6

I just read today someone having an issue like this with those cells in a q8.
I have 4 waiting already charged for my q8 due in Monday. I hope they work. 30q are my favorite.

7

Got 4X4-pack, in late August
All batteries had ~3,45V (a little too low… possibly because of airplane transport?) , all had 2850-2900mAh tested @ 4 amps.

8

Thanks for the feedback. Looks like I’m just unlucky.

I bought 2 sets of 4, in plastic boxes. Each cell individually shrink-wrapped for further insulation in transit. Don’t know which box(es) the duds were in since I mixed them up.

All were charged at 3.41 V. All charged up to 4.19 in my old Nitecore i4

Getting ready for Q8 arrival I was “exercising” i.e. discharging to cutoff voltage, each cell in a C8 which pulls at most a modest 2.5A or so. Then re-charging,

The dud cells could only drive this for a couple of minutes before LVP. Measured 3.46V afterwards, rested. Appear to charge up again (quickly), but again, no significant capacity afterwards. Tail current also well below the good ones.

Time to buy an analysing charger anyway. Other cells seem good. All marked “Samsung SDI 136”.

9

You do have my address for my xmas present, don’t you uncle delta?

10

I have had a number of fake 30q cells over the past two years.

11

How weighing a 30Q certainly original? Flat
I have one I’m using and weigh 45.94 grams
Other 4 still unused weighs from 45.86 to 45.93 grams
I’m worried about the 30Q by 45.86 g.

12

i also order 4 along with my BLF Q8 on the same day but different order number. Got refunded. oh well.

13

All I can say…… you’re not alone.

14

Mine were low charge too. 3. 4 something. I thought that seemed low.
We will see how they work soon. I hope they are not fakes

15

I think they are kept a low voltage to satisfy air safety regulations. Plus they last longer in storage at that voltage.

I just got a button top 4 pack in a plastic case from banggood, but I haven’t charged them yet. One had a bad wrapper, so they sent me a replacement. That’s the only bad thing I’ve experienced.