Battery Polarity Protection

maklabouhlel

maklabouhlel

maklabouhlel

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Hi all, I just replaced two Li-ion 18650 batteries in my rechargeable fan and one of them started smoking vigorously and the spring contact went glowing red. The originals were in parallel but I installed the new ones in series. Whilst I accept my stupidity and ignorance, shouldn't there be some sort of protection in place?
 
maklabouhlel said:
Hi all, I just replaced two Li-ion 18650 batteries in my rechargeable fan and one of them started smoking vigorously and the spring contact went glowing red. The originals were in parallel but I installed the new ones in series. Whilst I accept my stupidity and ignorance, shouldn't there be some sort of protection in place?
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Not if its not end user serviceable. Also its not really polarity protection that would have saved you, you've doubled the voltage through the circuit, not got the battery in the wrong way.
 
Minstadave said:
Not if its not end user serviceable. Also its not really polarity protection that would have save you, you've doubled the voltage through the circuit, not got the battery in the wrong way.
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I'm not sure what you mean exactly but the device is designed to have its batteries replaced when worn out. Also, the +ve and -ve ends of the original batteries look identical and the polarity is unlabeled. Surely there should be a warning or something but there's no mention on the device or manual.
 
`Some`Li-ion 18650 batteries look nearly identical on both ends (flush)but if you look carefully they are different
Should be a plus or minus on the end though
 
I don't think you connected the batteries in series, surely you connected one battery on correct polarity and one in reverse polarity? And the reverse polarity one smoked?

So no doubling of voltage.
 
ANDARIAL said:
`Some`Li-ion 18650 batteries look nearly identical on both ends (flush)but if you look carefully they are different
Should be a plus or minus on the end though
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There was no +/- on either end. I've contacted the manufacturer as this is obviously a fire risk as there will always be some people putting the battery the wrong way round.
LuckyBenski said:
I don't think you connected the batteries in series, surely you connected one battery on correct polarity and one in reverse polarity? And the reverse polarity one smoked?

So no doubling of voltage.
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You're right, that's exactly what I did. I've sent it back to the manufacturer for obvious reasons. This years model allows the battery to be replaced but this wasn't possible on last years otherwise identical unit. It looks like they've not modified the circuit to protect from this type of error.

S4gNIrF.jpg
 
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maklabouhlel said:
There was no +/- on either end. I've contacted the manufacturer as this is obviously a fire risk as there will always be some people putting the battery the wrong way round.

You're right, that's exactly what I did. I've sent it back to the manufacturer for obvious reasons. This years model allows the battery to be replaced but this wasn't possible on last years otherwise identical unit. It looks like they've not modified the circuit to protect from this type of error.

S4gNIrF.jpg
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If that was AAs they're generally plus one way and minus the other, however my mouse (a logitech one), has them both pointing in the same direction like I assume that is (based on the springs).
 
maklabouhlel said:
There was no +/- on either end. I've contacted the manufacturer as this is obviously a fire risk as there will always be some people putting the battery the wrong way round.

You're right, that's exactly what I did. I've sent it back to the manufacturer for obvious reasons. This years model allows the battery to be replaced but this wasn't possible on last years otherwise identical unit. It looks like they've not modified the circuit to protect from this type of error.

S4gNIrF.jpg
Click to expand...
It's on the back of the battery cover?
 
Sorry op just googled the type of battery. They do look like a li-ion AA, but just from a 5 minute Google it looks like they don't have the nipple on that the AAs (which is stupid imo). Have you got a pic of your batteries?
 
Weird.the cover says 5V but 2 x AA would be 3V and 2 x Lithium 18650 would be 7.4V as 18650 are 3.7V unless i am wrong
`flush`+ ends on a 18650 are `easy` to identify though,at least they look different to me :)
 
ANDARIAL said:
Weird.the cover says 5V but 2 x AA would be 3V and 2 x Lithium 18650 would be 7.4V as 18650 are 3.7V unless i am wrong
`flush`+ ends on a 18650 are `easy` to identify though,at least they look different to me :)
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It says 5V INPUT.

Your phone also has a 5V input and a nominal 3.7V lithium battery.
 
theone8181 said:
Sorry op just googled the type of battery. They do look like a li-ion AA, but just from a 5 minute Google it looks like they don't have the nipple on that the AAs (which is stupid imo). Have you got a pic of your batteries?
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This is a picture I took before I returned the item. They look like the batteries in blue which I got from some website but there was no +/- labelled on the purple ones:

oIGqloj.jpg
 
Thanks for the pic.That is the positive end showing on the purple battery :)
Bit of useful/useless info you can get small magnet thingys that add the `knob` onto a knobless battery
 
I didn't even know 18650 batteries existed so I'm pretty sure many others haven't and are prone to making the same error as me. Starting a fire just by placing one of the batteries wrong way round is very dangerous and for a reputable company, there should be a recall.
 
maklabouhlel said:
Hi all, I just replaced two Li-ion 18650 batteries in my rechargeable fan and one of them started smoking vigorously and the spring contact went glowing red. The originals were in parallel but I installed the new ones in series. Whilst I accept my stupidity and ignorance, shouldn't there be some sort of protection in place?
Click to expand...
You see, in the photo you posted, that there's a label stating, "If it is not working properly, contact a qualified electrician or service centre for examination and repair. Never try to dismantle it by yourself".....?

Does the manual give instructions on how to replace the batteries and with what type you should replace them?
If not then, as the label says, you shouldn't be doing it.
They've told you not to do it. That's probably protection enough, legally speaking.

ANDARIAL said:
ok :)

But would a 5V input be enough to charge 2 X 18650 batteries:confused:
Can you post pics of the original batteries?:)
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There are various devices using 18650s that charge off a 5v USB. Those that support 2A charging (as stated on this device) are generally favoured.
It's not as fast as using an external battery charger, but it's relatively reliable.
 
ttaskmaster said:
You see, in the photo you posted, that there's a label stating, "If it is not working properly, contact a qualified electrician or service centre for examination and repair. Never try to dismantle it by yourself".....?

Does the manual give instructions on how to replace the batteries and with what type you should replace them?
If not then, as the label says, you shouldn't be doing it.
They've told you not to do it. That's probably protection enough, legally speaking.
Click to expand...

According to the website: "New for 2022! We listened to your feedback and have updated the Fan to enable battery replacement, meaning the new and improved fans can be used for many years to come!"

I think there's a big difference between not working properly and replacing batteries.
 
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