Xiaomi style battery charger. Near disaster today – flames – when I put a battery in

Today I got to see what destructive force 18650 batteries can have.
I got some Xiaomi style 4 x 18650 power banks from Gearbest.com today (this type).
Wanted to test one of them, and found 4 Sanyo UR18650ZY batteries, that I have tested and tested, and then used same type in different flashlights etc.
As soon as I put in first battery in the power bank, it burst in to flames. I trow the whole thing away on the floor, landed right under my pants (that was on a chair), so I quicly had to remove the device, still burning, and then trow it hard to the ground to try to get the battery out, or destroy the power banks so the fire stopped. And it did.

As you can see on the pictures under, the coil in the power banks has been so hot that it melted the plastic, that took fire. Not a pleasant experience.
I was afraid the battery whould explode, that was the reson that I just trow it away, not trying to remove the battery. Do not know what was the right thing to do in this situation?

The power banks can only fit unprotected flat tops batteries like most power banks, and the power bank should stop short circuit, over/under charge etc. Clearly the Xiaomi style power bank Gearbest.com sells, do not prevent such things.

Here is the info from their website and the power banks:

Oh, no.
Luckily you’re ok, something even worse could happen.
I’m not sure that’s authentic Xiaomi power bank box. I have original 10400mAh Xiaomi and its looks different than from your link.

ouch! and lucky you!

it could have been way worse than that!

Glad you are okay, and your house!

No it’s not original Xiaomi, it’s Xiaomi style. :slight_smile: The real Xiaomi power banks comes with batteries and can’t be open (easily). Still, Gearbest.com claims that this has the short circuit protection etc, so this should not happen I think?

my xiamoi powerbank feels like aluminum case not plastico

but of course aluminum can burn too if the flame is hot enough

xiaomi makes powerbanks that you can load with cells? I did not know that.

Did not know that. But I knew this was not a real Xiaomi PB, since they sell it as Xiaomi style PB. Still, did not expect bursting in flame putting in one battery, and of course, it was the right direction ( + / - )

Yes, it has aluminum case outside, this is inside there the batteries is, and of course, no metal there.

Ah I see it’s “Xiaomi Style”, not Xiaomi. Just buy the real thing, not this “style” dangerous garbage.

Good to hear you weren't hurt. Most decent cells will take a dead short for a little while before they blow. I know first hand, more than once.

The problem with the listing on GearBest’s site is, although this is an Xiaomi “style” power bank shell, they’ve reused the copy from the real product. I doubt it has any of the safety features of the real one, as you have unfortunately discovered! Is it possible you inserted that battery backwards?

edit I see you are sure the battery was installed the correct way. If you have a multimeter I would try measuring the resistance between the + and - contacts to see if there is a dead short.

But the battery did never blow, still I have put in into my fireplace now, just to make sure.

No it’s was inserted the right way. The batteries has a plastic label with info, and with a + and - sign.

And here is a picture of the battery, and you can see thats the rear end that has been in the fire.

Something wrong here (besides GB apparently posting the real Xiaomi information along with their “Xiaomi style” cheap copy — which is really, really stupid.

Look at the questions on the page down at the bottom:

So —- the case you point to is not supposed to be taken apart, if that answer from GearBest is accurate (also not necessarily to be relied on).
(From the description elsewhere it’s not at all clear if they ship it with, or without, any batteries)

Why did you take it apart? Did it come with batteries in it? Did you remove all the cells first, then put a single cell in and it exploded?

The only time I’ve seen a power bank heat up like that was when TWO cells were put into it, one of them backwards, causing a dead short circuit.

It still has 4.20V when I use my multimeter. So the battery seems OK. But it smells burned from it still. But it’s not hot or something. But I have so many batteries, that I will never use that again, just to be sure.

Do you or any other know where (which store/seller etc) that ships to Norway, that have real Xiaomi empty power banks that I can use my own batteries on?
See several on Aliexpress, but don’t know if they just use real pictures from Xiaomi, or not. And in the Xiaomi store I can’t find DIY cases…(maybe I have overseen some?)

Look here, this is what I got from Gearbest.com from the page that I linked to:

I just put in the one battery, then it started burning right away.

If you wanna consider other diy power banks have a look at HKJ reviews. I bought some of the stuff he tested including Coolook PB-2000 diy power bank and its working very good.

The whole point is to get a cheap, but still quality, power bank, that I can use my own batteries on. If the price is $15 or more, with the price of 4 batteries, I will come better out buying real Xiaomi power banks (not DIY).
A 10400 Xiaomi PB costs from $17-21 on Gearbest, lower prices other places. Their 16000mAh PB cost $24. So maybe I just drop the idea making my own PB and buy real ones. It’s safer, and I can earn almost the same money on it.

The cell bank that caught fire could have shorted out with the case of the cell next to it. I notice that the current only went through that one spring. I think the cell next to it had popped up so that the negative case on that cell was toughing the positive terminal. Then when that last cell was in the process of being inserted, it shorted out through the case of the cell next to it. i would like to see the contacts of the case on the positive side.

There was no other batteries in the case. I had just opened the package and the PB, then I inserted the first battery, then it started to burn right away, or first it made a sound, got really red, and I throw it, in the same second it start to burn a little. As you can see from the damage, we are not talking about a huge flame or fire, but it burned, so when it landed under my pants, I had to do something really quick…

Here is the pictures from the other side, as you can see, no damage there. If I had put two batteries in, would there have been any damage on the positive side also?

I dont trust cheap chinese items.

I always prefer going with genuine devices.

I was thinking to buy that 18650 power bank box… but now… obviously not

I know you swear you put the cell in the right way, but to me it looks like you put that one cell in backwards and the positive and negative of the cell shorted out on the spring. I can’t explain the picture of the negative end of the cell. Can you take a picture of the positive end of the cell?