Burnt out a 2-AAA LED Maglite

[MattD201]

I burnt out my 2-aaa LED Maglite by using NiZn cells. I wanted to go brighter than what NiMH was giving me, but also prefer rechargeables vs. Alkalines.

The tiny LED just melted off in less than 5 minutes. I was surprised because my understanding is that NiZn cells are 1.65 volts; so two of them at 3.3 volts is not much more than 3.0 for a set of fresh Alkalines.

Has anyone else had this experience? Also, is there a way to replace just the LED module in the Maglite? I don't think a warranty claim is right because I did overdrive the light.

If I do have to replace it, the preference is something more durable and forgiving than the Maglite. Any recommendations for an alternative 2-aaa penlight would be appreciated.

 

[thermal guy]

I think they can be up to 1.8 volts when fully charged.

 

[Hooked on Fenix]

Get anything that is rated for up to 4.2 volts. Some lights are designed to take two alkalines (1.5 volts each) or sometimes one lithium ion cell (4.2 volts). Anything short of that, you'll probably fry a light designed only for alkalines using NiZn cells. One such light is the Princeton Tec Alloy-X Rechargeable l.e.d. penlight.

 

[chillinn]

The tiny LED just melted off in less than 5 minutes.
...
Has anyone else had this experience?

I've never heard of an LED that wouldn't melt. You just need to give enough voltage and liquidity ensues.

 

[MattD201]

Get anything that is rated for up to 4.2 volts. Some lights are designed to take two alkalines (1.5 volts each) or sometimes one lithium ion cell (4.2 volts). Anything short of that, you'll probably fry a light designed only for alkalines using NiZn cells. One such light is the Princeton Tec Alloy-X Rechargeable l.e.d. penlight.

Thank you for the recommendation for the Princeton penlight. It looks like a really solid light, and worth the premium price vs. Maglite. I don't even have to use the NiZn cells because it comes with a rechargeable battery.

 

[MattD201]

I've never heard of an LED that wouldn't melt. You just need to give enough voltage and liquidity ensues.

Many quality lights usually have voltage boosters and regulators, which can handle a nice range safely. I even have a cheap Coast light which can handle a NiMH AA, an Alkaline, or a 14500. More lumens from the 14500, of course; and no melting.

I guess that Maglite has decided not to include these circuits.

 

[jabe1]

Brightness in LEDs is determined by amperage, not voltage. They require a somewhat steady voltage ( forward voltage) typically somewhere around 3-5 volts iirc.
You'll see people referring to how hard an LED is driven, measured in amps (current), which will be the primary determinant of brightness.

 

[chillinn]

You'll see people referring to how hard an LED is driven, measured in amps (current), which will be the primary determinant of brightness.

Does this mean that a 1.2V 5A LED light will be brighter than a 7.4V 3A LED light?

 

[MattD201]

Brightness in LEDs is determined by amperage, not voltage. They require a somewhat steady voltage ( forward voltage) typically somewhere around 3-5 volts iirc.
You'll see people referring to how hard an LED is driven, measured in amps (current), which will be the primary determinant of brightness.

The single AA lights such as the Lumintop Tool AA and the Coast HP1 are rated at much higher Lumens when a 14500 cell is used. There must be a design in the circuit which allows the difference.

One possiblity is that a higher voltage across a diode cause higher amperage to be allowed through.

However it is accomplished, in those two lights we can use 1.2, 1.5, 1.65, or 3.7 nominal voltage cells safely, and with a noticeable (and advertised) increase in light output corresponding to the supplied voltage.

In the Maglite, I went from 3.0 to 3.3 (or possibly 3.6) volts, and now it is zapped.

 

[MattD201]

Does this mean that a 1.2V 5A LED light will be brighter than a 7.4V 3A LED light?

Based strictly on power usage, we are comparing 6.0 watts to 22.2 watts. I would think that the 22.2 watt LED will be much brighter.

 

[MattD201]

Based strictly on power usage, we are comparing 6.0 watts to 22.2 watts. I would think that the 22.2 watt LED will be much brighter.

Oh wait, you already knew the answer to that!

 

[PhotonMaster3]

Ya I did some thing similar with a Nitecore penlight. Put a lithium ion in by accident and it sure was bright! For about 5 seconds until it burned out and never worked again

 

[chillinn]

Oh wait, you already knew the answer to that!

Sorry. I am a smart ash. Jabe1 seemed to be laying down a rule of thumb, and I didn't want any n00bz to get the wrong idea. Thank you for playing.