Lithium lights without low voltage warning

mighty82

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How is this suppose to work? I read the low voltage warning function was removed from the Olight M20 and other lights.
It's kind of dangerous not knowing when the low voltage cutoff in the battery is going to kick in. I was walking down some dark stairs with my D10 here the other day and :poof: darkness.. I was so suprised I almost fell down the stairs! A regulated light on protected li-ion will rarely give you any signal that the battery is about to go out until it does. Especially if it doesn't have a low voltage warning. So, how do others deal with this "problem"? :)
 

Burgess

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Well, first of all . . . .


We follow the: " Two is one, and one is none " rule.


:candle:
_
 

aussiebob

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Carry spare batts, i suppose.

I remember a year or so ago before i had many fancy lights, we were camping, it was night time, i went to the dunny or something by the light of my mini mag 2aa and it just went out:poof:, no warning at all, so i tapped it a bit, still no workie, no moon, dark as buggery, had to half feel my way back to the tent, i thought it had packed it in, untill i put new batts in it, worked again. The 2aa only does this, the 3aa doesnt it goes dull for ages, weird? Damn maglite.

Any how i dont use regulated lights with li-ions so cant comment.
But my 6p e2e and g3 are all on li-ion and they cut out sometimes faster and sometimes slower. Sometimes they get more yellow before cut off.
 

Oddjob

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I change and top up my Li-ons fairly frequently. Doing this ensures I am using fresh batteries and it is better for the cells to be topped up frequently rather than letting them be discharged close to the point where the protection circuit kicks in. A digital multimetre is useful for determining how much juice is left in a cell as well. For my lights that have no low voltage warning I use primaries and of course I am never without a back up light. Proper Li-on use does require more attention but I enjoy taking care of and maintaining my gear so it's just part of my routine.
 

hopkins

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hey mighty82 - like many of us with electronic controlled flashlights,
your incident report shows they ain't the panacea we'd hope for.

-imagine the news headline: High Tech Flashlight Kills owner on Stairs.
My headline could have been: Man cuts off fingers with with power saw when headlamp failed. I was lucky and I saw the light.:ohgeez:
Direct drive lights only when doing anything that could result in injury if the light
were to suddenly die.

Dimming can be managed much better than sudden darkness from full brightness of a regulated
-hopkins.
 

mighty82

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hey mighty82 - like many of us with electronic controlled flashlights,
your incident report shows they ain't the panacea we'd hope for.

-imagine the news headline: High Tech Flashlight Kills owner on Stairs.
My headline could have been: Man cuts off fingers with with power saw when headlamp failed. I was lucky and I saw the light.:ohgeez:
Direct drive lights only when doing anything that could result in injury if the light
were to suddenly die.

Dimming can be managed much better than sudden darkness from full brightness of a regulated
-hopkins.
I agree. Regulated lights in general is not a problem, because they usually give several hours of light after they drop out of regulation. But lights using li-ion won't drop out of regulation, they will just shut off when the protection circuit cicks in with no warning at all. Even if they are direct drive, the cut off can come as a suprise.

Of course I carry spare batteries, but usually not on my body when im at home. I also top off the batteries often.

In some critical situations new batteries doesn't help much. Like a few weeks ago there was a storm here, and I was out all night trying to fix windows that were crushing and other stuff. In these conditions you really don't have time to stop and check your batteries. When you are running outside in total darkness or messing around with broken glass and power tools and your flashlight suddenly goes :poof: it can be a shocking
experience. Just 10 seconds of warning would help a lot.

The problem they have with the low voltage warning comes from that they are trying to make it work both with 1xli-ion and 2x lithium primaries. You don't even need a warning when using primaries, so why don't they just set the warning to 3.2V and be done with it? :sigh:
 

Illum

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Carry spare batts, i suppose.

Unless you've conditioned yourself to reload in the dark I'd suggest a second gun...err...flashlight :thumbsup:

Not all flashlights are polarity protected, and if your trying to replace new cells you may inadvertently do something wrong and will never know it until you try to click it on
 

Burgess

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Yep, carry spare batteries . . . .



Inside a spare flashlight. :whistle:

_
 

hopkins

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Well its finally come to the absurd point of having to hang a little keychain
LED light on the back of the regulated flashlights here so that when they die suddenly I'll have a backup. No falling down stairs for me Mr Wizard!:thumbsup:
 

jzmtl

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Carry spare primaries. I use a rcr123a in my EDC but I always have two primary 123a on me.

And a spare aaa flashlight.

And a spare aaa cell.

And a fauxton on keychain.
 

mighty82

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The light being regulated or not is not really the issue here. Any flashlight, regulated or not, will cut off without warning when using protected cells. Regulation is not the enemy. Every regulated flashlight I have will give me plenty of time to change the batteries before it turns off. As long as i'm not using protected cells.
 

LukeA

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The light being regulated or not is not really the issue here. Any flashlight, regulated or not, will cut off without warning when using protected cells. Regulation is not the enemy. Every regulated flashlight I have will give me plenty of time to change the batteries before it turns off. As long as i'm not using protected cells.

No, only buck-boost regulated lights cut out without warning. And using the protection circuit as bottom limit is a bad idea, as it shortens cell life. Running unprotected cells is also a bad idea.
 

mighty82

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Yes. Like I said, I charge my batteries often, even if I havent used them much. So they are usually topped off when I leave the house. It's just that in some situations I have to use the flashlight for several hours, and I really don't have a stopwatch on me to tell me when i'm suppose to change the batteries. :ohgeez:

It's just a big step back having to always be prepared for instant darkness. Even if I have a backup flashlight in one of my pockets, sudden darkness sucks. :rolleyes:
 

Illum

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Well its finally come to the absurd point of having to hang a little keychain

absurd maybe, but often times its better than striking up a phosphor flare while standing in a methane pocket

theres NOTHING wrong with keychain lights:twothumbs

:hahaha: :poof:
 

hopkins

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Got it Illum ! I'm just laughing at our high tech flashlights and the smug
feeling of "Aha! I'll never be in the dark again, and by the way, look how shiny and neat it looks".
Any flashlight that goes suddenly dark due to regulation OR protection circuits
sucks. At least with a cheap old plastic flashlight you could shake the darn thing and get some more light. Is this progress? I feel its 2 steps forward and 1 back
kind of thing.
 

Jarl

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I think the idea of no portection is so that batteries with different voltages (LiFeSo4 or whatever it is) don't make the light do the low battery voltage warning when the batteries still have most their capacity left. However, I agree it can be a bit scary when your main light gives out, hence the backups, though ;)
 
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