The dangers of rechargeable lights

[dodgy]

I wonder if keeping lights in an unused biscuit tin while charging is a sensible precaution? Keeps them away from anything instantly flammable and buys you some time?

 

[Johnno260]

I wonder if keeping lights in an unused biscuit tin while charging is a sensible precaution? Keeps them away from anything instantly flammable and buys you some time?

I charge mine in the kitchen, on a glass chopping surface, not a fan on enclosing them in case heat builds up.

 

[the_mikey]

I presume that it being charged through a USB port? In which case, the light was being supplied with 5 Volts. The common lithium ion cells should be charged to a maximum of 4.2 V. My suspicion is that the charger circuit failed (short circuit is a very common failure mode), allowing the full 5 V to get to the battery. Even a high quality cell will go pop quite spectacularly if treated that way.

If the light was made by who I suspect, then it's (should be) of reasonable quality. You ought to email them that photo, and explain what happened. It could be a design fault, or that they got a batch of counterfeit charge supervisor chips (that sort of thing is surprisingly common!).

Indeed, some phone chargers supply more than 5v dc, and whilst they should default to the 5v USB standard it's not inconceivable that the output might vary. When I charge USB lights I use a plain old 5v 500mA charger.

 

[dodgy]

I charge mine in the kitchen, on a glass chopping surface, not a fan on enclosing them in case heat builds up.

At least they won't roll off the surface as happened to the OP

 

[Johnno260]

At least they won't roll off the surface as happened to the OP

true there is that, but it's the other reason I use the kitchen, nothing flammable on the sideboard, glass surface and tiled floor.

No way I trust these things near a wooden/carpeted floor etc.

 

[CUBE CRD]

I charge my lights with the usb lead supplied,on a non combustible surface and the charger plug is one of those surge protected jobbies from Masterplug.

 

[classic33]

I charge my lights with the usb lead supplied,on a non combustible surface and the charger plug is one of those surge protected jobbies from Masterplug.

The surge protection is there to protect anything plugged into them from a surge in supply. Not to prevent anything plugged into them delivering a power surge.

 

[mjr]

In this situation it was plugged into a genuine Apple charger thus presumably, though wrong on that front, giving a charging combination that was, relatively, safe.

Genuine Apple charger for what, though? Some of them are 2.1A output and some lights (anyone with the same Lezyne like to tell us what it says on an unmelted one) only want 0.5A (standard PC USB).

Anyway, always charge this stuff on a heatproof mat. Even some big brands use sadly cheap batteries or chargers.

 

[CUBE CRD]

The surge protection is there to protect anything plugged into them from a surge in supply. Not to prevent anything plugged into them delivering a power surge.

Yeah,i'm aware of that.I should have been a little clearer.
I try and use as safe a set up as possible,both to protect my equipment and the surrounding furnishings.

 

[User33236]

At least they won't roll off the surface as happened to the OP

It didn't roll off a surface. It was pluged into a standad wall socket about a foot or so up from floor level and projectoed itself outwards from there.

 

[Milkfloat]

Genuine Apple charger for what, though? Some of them are 2.1A output and some lights (anyone with the same Lezyne like to tell us what it says on an unmelted one) only want 0.5A (standard PC USB).

My understanding is that it is pull rather than a push - just because the charger can provide 2.1A does not mean that it has to - that is up to the device drawing the power?

 

[User33236]

Genuine Apple charger for what, though? Some of them are 2.1A output and some lights (anyone with the same Lezyne like to tell us what it says on an unmelted one) only want 0.5A (standard PC USB).

Anyway, always charge this stuff on a heatproof mat. Even some big brands use sadly cheap batteries or chargers.

Whiltst a charger may be able to deliver 2.1A there in no guarantee that a device will draw that and a resposible manufacturer would ensure their devices were designed to limit charge current to a safe level.

EDIT: @Milkfloat beat me to it

I have another two, unmelted, lights of the same model. There is no writing on any to state charging voltage or current.

 

[mjr]

My understanding is that it is pull rather than a push - just because the charger can provide 2.1A does not mean that it has to - that is up to the device drawing the power?

Yes, but some Apple chargers did deeply non-standard shoot like sending voltages along the data lines to control the current supply. I don't trust any Apple or Samsung USB chargers to behave sensibly with dumb devices.

...and a resposible manufacturer would ensure their devices were designed to limit charge current to a safe level.

Indeed, but I thought we were talking about Lezyne?

 

[User33236]

Yes, but some Apple chargers did deeply non-standard shoot like sending voltages along the data lines to control the current supply. I don't trust any Apple or Samsung USB chargers to behave sensibly with dumb devices.


Indeed, but I thought we were talking about Lezyne?

Up until now I have not mentioned Lezyne anywhere in this thread

However now you have brought Lezyne up in the context you did I presume you have evidence to defend yourself in any defamation lawsuit that may, hypothetically, result?

 

[PhilDawson8270]

Yes, but some Apple chargers did deeply non-standard shoot like sending voltages along the data lines to control the current supply. I don't trust any Apple or Samsung USB chargers to behave sensibly with dumb devices.


Indeed, but I thought we were talking about Lezyne?

That's actually standard.

There's a default low limit, which I believe is 5v 500mA. The charger will only supply more upon a successful handshake with the device via data lines to charger to enable higher currents, or higher voltages.