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Exploding power bank due to induction?

Posted: Sun Aug 23, 2020 11:46 am
by sTeamTraen
I just got a new power bank. It would have cost €3.20 for 5000mAh except I got it free because I spent over €50 at the supermarket. (It's fairly amazing how cheap this kind of useful item has become. Well done China. Erm.)

Anyway, on the packaging was this warning. But what does it mean? At first glance it seems to suggest that there is a danger of explosion if I allow another cable that is carrying AC current to come near to the 5V USB charging cable of the power bank, perhaps by some phenomenon of induction in the charging cable. Is this a documented phenomenon? If so, exactly what precautions should I be taking (and why is the warning graphic so difficult* to understand)? The case says that the device has "anti-explosion protection", but normally I would be thinking in terms of physical damage causing leaks.
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*Yes, this is only my opinion, but I suspect most of the population wouldn't work it out very quickly.

Re: Exploding power bank due to induction?

Posted: Sun Aug 23, 2020 1:36 pm
by shpalman
I don't think there's much chance of induction from a cable which contains both live and neutral cores, even if it's carrying alternating current current, since the current which is alternating in time is anyway going in opposite directions in the two cores so that the magnetic field mostly cancels out. Unless you have the wires practically touching because you bundled them together, anyway.

The current in the low-voltage cable to the power bank would probably be higher than the current in a mains cable anyway.

I don't know if spikes or noise on the cable can confuse the charging circuit.

Re: Exploding power bank due to induction?

Posted: Sun Aug 23, 2020 3:37 pm
by Martin Y
shpalman wrote: Sun Aug 23, 2020 1:36 pm ... I don't know if spikes or noise on the cable can confuse the charging circuit.
That's the only risk I can imagine they're thinking of: that electrical interference might confuse the charging circuit into overcharging the battery.