A Vapcell 18650 M35 3500mah leaked inside my LT1 lantern
It’s the first time i have had a battery leak, anybody else experienced this ?.
Never ever! Sure it’s the battery, and not ingress of rain or something like that?
You should inform Vapcell Dennis about it. This is so rare (to me).
This could be a one off incident, but maybe the whole batch is compromised.
Are the markings and/or logo’s on all four cells identical?
That’s about manufacturing.
Now about warranty. Where did you buy these cells? Contact the seller.
IMHO you must insert flap top cells in this light. Sure you did not short the light?
First a vent, followed by a leak? What about the other cells.
I’ve had a few cells leak. Mostly older cells and just a couple of new cells.
I had one leak. It was a cheap included battery in a off brand flashlight.
The LT1 has been standing on my bookshelf, so no ingress of any kind.
All four cells looks identical and was bought at the same time from Vapcell on AliExpress, delivered : 2021-06-21 14:28.
They have been charged no more than 5 times in my Vapcell S4 Plus charger on auto setting.
No shorts, I believe button top batteries are are best for the LT1.
I did contact Vapcell on AliExpress, they offered me a discount on my next order.
The other three cells look fine for now, but i have discharged them and will not use them anymore.
I bought 2 * 4 cells they are all going to recycling.
Good, new cells just don’t leak, and yours leaked sitting upright. Please if you can peel the cell and see if you can post pics on the cells maker and model. A pic around the cleaned up button top please. I think when the button got welded on it got pierced. If your cell started to self drain with internal issues. The other 3 cells would have been part of the problem as they self balance the voltage dumping their power into a dying cell. Vapcell claims to only use the very best manufacturers of cells. Maybe not so good welders. Normally you could have used those cells in the lantern full power over and over again without issue. You said you charged the cells about 5 time since you got them a few months ago. Did they appear to be more drained than the usage would have been?
There is no markings at all on the battery. Here are some images (click to embiggen)
I didn’t notice abnormal battery drain, but the lantern doesn’t get much use this time of the year.
EBL 14500 in a GTmicro that was just sitting around minding its own bidniss.
Used fairly regularly, too, so not just “forgotten about” and left in a drawer for years.
I had two cells go south in the last year. They both developed rusty crusties between the negative and positive cap. An 8-year-old Panasonic b flat top started staining the white insulating ring with a rust colored something. I used it for a few cycles and then decided it was best to stop. I peeled things back to have a look and as I said just a little bit of rusty crusty stuff. The other was a rewraped 2600 Wowtac with the micro USB charging apparatus on the top. When I found that one it was already dead. I pulled off the micro USB charging stuff and a bunch of rusty crusty at developed again between the positive terminal and the casing. There’s a very small gap there so it doesn’t take much crusty to develop a micro short and drain the battery when you’re not looking. There have been other issues with that lantern and batteries because of the positive end having to be twisted into place with brass shavings from sharp positive terminals. I can understand wanting to charge them externally to watch what happens but constantly removing and reinstalling things may not be a good idea with that light. And you’re going to have to be very careful the next couple cycles with that light with that battery juice potentially contaminating things.
Samsung and Molicel make INR18650 cells optimistically rated “3500” mAH, the –35E and -M35. Both are flat top cells but of course anyone can add a button top.
i would guess that Vapcell is using the Moli , getting small button tops welded to the flat top, and rewrapping with their label. But it could have been a fake Moli.
edit Not a Moli since it has 5 vent slots instead of 4. The sharp edge at the top is quite strange, usually would expect to see a rolled edge. Maybe a picture of the top of one of the other cells with all the covers peeled out of the way would show what was done to modify the flat top.[/edit]
Molicel datasheet (may not be official since there is no address or contact phone number): https://cdn.shopify.com/s/files/1/0481/9678/0183/files/moli_INR18650M35A-02-0.1_a3a5a1d7-dbb6-4b49-b753-e16a565d4c2d.pdf?v=1614794896
You could remove the insulation around the top and button to measure if the dimensions match the diagram on page 10; also weigh the cells if you have a small gram scale to see how they compare to the spec value.
I would not assume the rest of the batteries are problematic. What is the voltage of the others? Any guesses as to what the voltage would have been when you last parked it and how long ago was that?
The wrapper seems to be deformed. It might had an overcurrent event, got hot and vented through the valve at the positive side? But I miss charred spots on the driver and the wrapper. Strange…
Thanks everybody for your input.
The rest of the cells are @3.89V, they look fine and there doesn’t appear to be any leaks.
I won’t be using any of the remaining batteries, I rewrapped the defective battery and taking all four to recycling.
i remember seeing that strange response. Sales and marketing folks are not a good source for technical support.
Is that Vapcell M35 previously a flat-top or did it have an added button-top?
I’ve bought a few Vapcell M35 (flat-top) to check them out since they’re fairly low price.
I don’t think they are from the bigger OEMs (ie. not from Samsung / Sony / LG / Sanyo / Panasonic / Molicell).
All of the Vapcell M35 arrived (from shipping condition) at around 3.77-3.78v, using YR1030 resistance tester, gets from around 30-34mOhms (which implies not very consistent). The samples I got weigh from around 46.5-46.8grams. Capacity test (using SkyRC MC3000, discharge at –0.50A, from 4.20v down to 2.50v, yields somewhere from 3300+ to 3400+ mAh capacity) The top has 5 lobes (seems a bit similar to “BAK” 18650s, but I cannot be sure).