Convoy S2 plus SST40 issues


I am new to this forum, so sorry in advance if some of the questions will be silly.

I got my self Convoy S2 plus SST4o flashlight. I am using recovered batteries Sony US18650GR 2100mah, Two new sony ncr18650b (from aliexpress so they probably not genuine) and some aliexpress trustfire batteries.
The issue I have is that in the spec it says flashlight can draw up to 5 amps. If i measure from tail cap I only get up to 3.4 - 3.2A. And after 15 - 20 mins it goes down to 1.5 A and flashlight start blinking (1s on 1s off). This is an issue with my batteries or is it flashlight itself?

I can almost certainly tell you that the problem is with the batteries.
Do you have the possibility of getting good quality batteries to test?

Are you measuring current with DMM probes or with a clamp meter? If it’s the former, you’re probably introducing lots of resistance with your meter.

Hi, I am using Fluke 189 multimeter.

I tried to stack 3 batteries together and I got 6.2A draw. So that says flashlight is ok. another problem flashlight is switching on and of every 2 seconds or so. But when I put in this new NCR18650B battery which is from aliexpress is not blinking, but the current draw is only 3.2A. Can somebody recommend where and what model battery to get for this flashlight? I live in Republic of Ireland.

That Panasonic resembles some of the models presented in the Massive fraud on 18650s in the Littokala Aliexpress stores! thread!
I’d suspect that is not an original panasonic cell…

Also, these cells are not for high drain flashlights, specially if they are protected (I can’t tell by the photo you presented).
If the flashlight wants to draw more current, the protection may interfere with that.

If you want original cells, check this AliExpress store:

I’ve bought many cells from them, with “fast” delivery even during Covid-19 situation, and they are original cells!

You can still get Panasonic protected batteries or you can get some Sanyo NCR18650GA, that have good capacity and are good for that 5A drain.

The way you’re measuring is adding loads of resistance to the circuit and will certainly affect the current draw. You need a clamp meter to get an accurate reading.

maybe somebody tried ? is it legit product up there or same as aliexpress ?

nkon has a good reputation.

These guys have a good rep in the UK:

EcoLux battery stuff…


And what model i should look for? As from quick look Samsung 35e looks like good deal.

Shop by price, since you probably don’t need more than 5A-7A of current handling, which just about modern cell will do.


Panasonic 18650GA (genuine ones) are really good for under 10A draw. They’re all I use for my low (5A to 7A) demand lights. Cheap cells or counterfeit ones will have high internal resistance and won’t allow maximum current. To get the best measurement for current, you need a clamp meter. Even a high end multimeter has too much resistance for an accurate measurwment.

Does anybody heard ?
As i can find, only they has sanyo / panassonic 18650GA for decent price.

Send NKON an email and ask them if/when the NCR18650GA will be in stock again.
He is used to sell large quantities, and reports “out of stock” below a certain volume
Tell him also how many you need, maybe he’s got just enough for your needs.

I have no negative information (eg. no info at all) about but they sell all kinds of batteries, including cells that fit into flashlights.
NKON focusses on flashlight(cell)s, and is my seller of choice. From way before I joined BLF.

Will do! thanks for information.

it;s got to be the [old, recovered] batteries.

the light {driver} is trying to get the 5A but when it gets over 3A, the voltage drops so much it has to back off trying for more


Using the Uni-T UT210E and a short piece of copper wire (maybe 1mm thick) to measure the tailcap current, I got around 4.5Amps max for the Convoy S2+ SST40.

This is a bit lower than the other SST40 4-mode drivers, which I measure tailcap current at around 5.5Amps (eg. C8+ SST40 4-mode, or S21A SST40 4-mode driver).

3.x Amps seems to be too low — may I ask how did you do your measurements? Also the batteries used?

I just took off tail cap and connected multimeter leads. Black to battery (-) red to flashlight chassis.

I done little upgrade. I put 1.5mm diameter wire inside springs in both side. Now I am getting 3.4 amps instead of 3.

Another thing what i done is thermal paste on the head and tube thread. That was terrible idea… Paste is not conducive. I had to clean it everything and new grease on threads. Do do it.