Battery run time question

CaptainpPicardX

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I might be dumb or something but I cant figure out something. Im talking about a 18650 battery, using it in my fenix Hl55. Im not really happy with the lenght of time it runs, but I really like this headlamp, dont wanna get rid of it.

So if I get a 3400 mah battery, button top, it is supposed to shut down my flashlight whenever it reaches down to 2.7v? or something

So, arent I technically getting only 65% or so of the battery run time then?

And if I end up getting the flat top, those are supposed to be able to drain down below 2.7v right? But thats not good for the longevity of the battery? Even so, the flat top, should last me longer(run time) than button top anyway tough?

So 3 questions there.

Would appreciate an answer.
 

Str8stroke

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Not a dumb question. There are a few things to consider:
Number One: Picard, Cajun??
Number Two: What brand battery & charger are you currently using?
Number Three: That light uses a Electronic Switch which typically has Paracitic drain. Meaning if you don't physically lock it out when stored, the light is always draining on the battery. The best, "not in use plan" is to unscrew the tail cap to break the connection or removing the cell. Thereby "Locking it out". I bet you will see a significant improvement in battery life by doing this.
Number Four: Lots of lights have a Low Voltage Cutoff for safety reasons. But keep in mind many Cells do too (AKA Protected). I don't know the voltage cutoff for your particular light. But, know that some batteries can possibly cut off at 2.7 volts too. FWIW: I have seen some cheap or faulty cells cut off at 3.0 volts.

Hope some of that info helps. I also searched that light here in the forum. It would be good idea for you do that too. Here is a link to a good review: http://www.candlepowerforums.com/vb...view-Fenix-HL55-Headlamp-(1x18650-or-2xCR123)
 

Timothybil

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Another point - a 3400 mA cell is a 3400 mA cell, whether or not it is protected. Either one will last the same amount of time in a light. The only difference is that an unprotected cell can be drained below recommended levels if the light does not have its own low voltage cutoff.
 

CaptainpPicardX

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Ive been debating whether I should get the Fenix Hl35, Im looking for something that has a high burst over 400 lumens for short time, but has a setting around 150 or so, that run for a long time. Hl55 seems has a 165 lumen supposed to run for 9 hours or so, but Im not getting nowhere near that. Im using the fenix 18650, and some rebranded panasonic cells, protected.

Based on that little review, it seems that the run ran only for about 4 hours on 165 setting, which is dissapointing.

Another reason why I was looking at Hl35 is cause I have c crane radio that I use for camping that runs on AA, so I was trying to have all my equimpent run on the same type of batteries. Instead of having to carry 3 x 18650 as backups, I could just have 8 AA in a case.

But I think the Hl55 even with protected cells probably runs longer on 165 lumens, than the hl35 on a similar setting.

If anyone has another headlamp with around 160 lumen setting, that actually gets 10 hr or so of run time, I'll take a look at that one too.

I wish the guy who did the review, just set it to 160 lumens, from the get go, and then seen how long it runs, instead of putting it on 900 first, and then seeing it drop off. I cant really tell if this light actually gets 10 hr out of 160 lumens or not. If so then it must be me not unscrewing the cap in order to get rid of the parasitic drain.

I thought fenix, panasonic cells were good. I doubt its the battery.
 
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cdm-dude

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Ive been debating whether I should get the Fenix Hl35, Im looking for something that has a high burst over 400 lumens for short time, but has a setting around 150 or so, that run for a long *** time. Hl55 seems has a 165 lumen supposed to run for 9 hours or so, but Im not getting nowhere near that. Im using the fenix 18650, and some rebranded panasonic cells, protected.

Based on that little review, it seems that the run ran only for about 4 hours on 165 setting, which is dissapointing.

Another reason why I was looking at Hl35 is cause I have c crane radio that I use for camping that runs on AA, so I was trying to have all my equimpent run on the same type of batteries. Instead of having to carry 3 x 18650 as backups, I could just have 8 AA in a case.

But I think the Hl55 even with protected cells probably runs longer on 165 lumens, than the hl35 on a similar setting.

If anyone has another headlamp with around 160 lumen setting, that actually gets 10 hr or so of run time, I'll take a look at that one too.

I wish the guy who did the review, just set it to 160 lumens, from the get go, and then seen how long it runs, instead of putting it on 900 first, and then seeing it drop off. I cant really tell if this light actually gets 10 hr out of 160 lumens or not. If so then it must be me not unscrewing the cap in order to get rid of the parasitic drain.

I thought fenix, panasonic cells were good. I doubt its the battery.


Surprisingly I have not tested my HL35 in MID with li-ions. In HIGH I get 3 hours, 20 minutes with two Fenix, 800 mAh 14500's.

Check this thread tomorrow, I might have a number for you.

As a side note: The HL35 is a versatile, all-purpose headlamp. If I could take with me just one headlamp w/o knowing how I'd be using it, the HL35 would be it. It is perfect for walking at night with a pair of trekking poles taking up your hands. The range on High is just right and those extra lumens in Turbo do come in handy from time to time. Having said that, if you need to make out something far in the distance, the HL35 won't cut it. Likewise, for any type of closeup work the hotspot in the middle becomes annoying fairly quickly. So, this headlamp is right there, in the middle. The red light is a huge plus, I use it fairly often but I guess what sold it was the versatility. I've run it off Alkalines, Primary lithiums, NiMH and even AAA eneloops (inside AA to AAA converters). You can't have that kind of versatility with the HL55, for example. Plus, the HL55 is bulky as hell. With HL35 you could use Energizer lithium AA's to cut down the weight even further. Two of them weigh only 30 grams(!). That's the weight of a single Energizer NiMH AA cell. Obviously, you won't get that extra output in Turbo mode out of non-li-ion batteries but I for one, am glad to have the option(s).
 

cdm-dude

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Well, I found the data. Turns out I did run all the tests with them new Fenix 800 mAh cells after all.

In Mid, which is rated at 70 lumens it is almost exactly 10 hours, give or take a couple minutes.
*In the specs on their site they put 8.5 hours but I tested my lamp with the more recent, new and freshly charged 800 mAh Fenix 14500 cells.

I know you were talking about ~160 lumens but this headlamp doesn't do "160 lumens". It's either the 70 in Mid or 200 in High, which will give you a little over 3 hours of runtime. The throw on this model is more than you'd expect from a typical headlamp, though. That's due to the hotspot that the beam has in the center. Headlamps, in general, produce more of a uniform beam that covers a wider area, so with those type of headlamps 70 lumens don't mean a whole lot in terms of reach. So, that's something to keep in mind.

With Energizer lithium AA's you'll get 4 and a half hours in High, which is more than an hour of what you can get out of Li-ions. The output in Turbo mode won't be so great though.

Hope this helps.
 

CaptainpPicardX

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Thanks. Ive used headlamps and flashlights for a while, somewhere around 160-200 seems to be the one I use most.. The only exception to that is when Im fixing something, I need around 50 or so.

200 lumen on that one, is just fine, its not too bright for what I do, but 3.5 hours is not enough... Looks like Im just gonna keep the Hl55, and do what that other guy said, just to start unscrewing the cap to eliminate the parasitic drain, and see if the battery lasts noticeably longer.
 

archimedes

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Message to OP .... @CaptainpPicardX you have had two posts deleted here, this is not the proper place for advertising your own auctions. Please do not do so again.

Thank you.
 
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hiuintahs

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......So if I get a 3400 mah battery, button top, it is supposed to shut down my flashlight whenever it reaches down to 2.7v? or something

So, arent I technically getting only 65% or so of the battery run time then?

And if I end up getting the flat top, those are supposed to be able to drain down below 2.7v right? But thats not good for the longevity of the battery? Even so, the flat top, should last me longer(run time) than button top anyway tough..........
100% of the capacity of the battery is rated within the working voltage of the battery: 2.50v to 4.20v. It's not exactly a linear relationship though.
 
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