Dissapointed with Fenix FD45; Resolved: battery issue

lightseeker2009

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When I first opened the package and started to use and test the light, I was very happy about my purchase. But very soon after I realized there is a problem... The light barely manages a minute or two on turbo mode, even though the manual states at least an hour. I tested the batteries and they were 1.24v for all 4. It seems with this light it will only go into turbo mode with freshly charged batteries. This cannot be right? I then took the batteries out and tested them in my TK40. The TK40 can work with 4 batteries also. It goes and stays into turbo mode on my TK40 no problem. So either my light is faulty or it's not a great light. I am very dissapointed.

EDIT: The problem was not the flashlight, but me using inferior NiMH batteries which could not deliver the amps this light needs in turbo mode. By switching to Eneloops did the trick.
 
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klrman

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Re: Extremely dissapointed with my new Fenix FD45

Could be faulty or they are omitting from the specs that it probably will step down to somewhere between 900 and 300 lumens for 90 minutes. Not the first time a manufacturer would fib to get extra sales.
 

lightseeker2009

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Re: Extremely dissapointed with my new Fenix FD45

I was told to rather use Alkalines. Will voltage drop not cause the same problem? And then, the 90 minutes runtime claimed by the manufacturer was done using NiMH.
 

ven

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Re: Extremely dissapointed with my new Fenix FD45

Alki leaks wont hold any decent amount of turbo with sag, not only that they cal leak! Eneloop pros would be the better choice for a higher output AA light(or even regular eneloops).

But what ever the cells used, 900lm will not be held longer than a few mins due to heat. 900lm is a big output for a compact light, physics gets in the way.
 

klrman

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Re: Extremely dissapointed with my new Fenix FD45

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lightseeker2009

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Re: Extremely dissapointed with my new Fenix FD45

Alki leaks wont hold any decent amount of turbo with sag, not only that they cal leak! Eneloop pros would be the better choice for a higher output AA light(or even regular eneloops).

But what ever the cells used, 900lm will not be held longer than a few mins due to heat. 900lm is a big output for a compact light, physics gets in the way.

I agree. Even my 8 cell TK40 can sustain Turbo mode only for a few minutes. And its got ''only'' 630lm.
But to refuse Turbo mode, even if cold? That should not happen I'm sure.
 

ven

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Re: Extremely dissapointed with my new Fenix FD45

I agree. Even my 8 cell TK40 can sustain Turbo mode only for a few minutes. And its got ''only'' 630lm.
But to refuse Turbo mode, even if cold? That should not happen I'm sure.

Problem is 900lm is just too much for alki cells, they are not good for any higher ask application(remote controls and clocks are good for alki cells). Have you any sanyo eneloops?(white or the black pro). If not they are pretty much a must for this type of light. It will transform your disappointment to happiness for $15 or so. The sanyo's are not the cheapest, but within reason, the best! Buy once cry once as Chris says.
 

ven

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Re: Extremely dissapointed with my new Fenix FD45

This is what you want
YHzOoOkl.jpg


Problem sorted:)
 

lightseeker2009

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Re: Extremely dissapointed with my new Fenix FD45

Problem is 900lm is just too much for alki cells, they are not good for any higher ask application(remote controls and clocks are good for alki cells). Have you any sanyo eneloops?(white or the black pro). If not they are pretty much a must for this type of light. It will transform your disappointment to happiness for $15 or so. The sanyo's are not the cheapest, but within reason, the best! Buy once cry once as Chris says.

My TK40 is stoked with 8 of them (2000mah white Eneloops) I could only find the others in a radio control transmitter this morning. I am at work now, so I will charge them after work and put them to the test.
No self respecting longstanding CPF member will be without Eneloops:)

But can normal non Eneloops be really so bad to cause this? I used Turnigy 2200mah NiMH's. If only Eneloops is good enough, should Fenix not state it like that?
 

ven

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Re: Extremely dissapointed with my new Fenix FD45

Having tried different nimh's over the years, i wont even buy anything other than sanyo these days. Too many poor experiences, most lately a panasonic AAA nimh that vented(uneducated guess would be aged cell). It got HOT, to hot to actually hold.

With an 8 cell light the load is spread across more cells(of course), sanyo eneloop white will be fine, more than likely fine in the fd45 as well(4 of). The pro are higher drain, maybe good for 5a or so and 2500mah V the 2000mah of the white loops. Now bare in mind your output is jumping from 600lm to 900lm, using 4 cells not 8. Those factors all contribute to more demand per cell on the pd45.

Good choice!!! I should have known:nana:
 

klrman

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Re: Extremely dissapointed with my new Fenix FD45

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WalkIntoTheLight

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Re: Extremely dissapointed with my new Fenix FD45

Yeah, Eneloops are the only way to go. They can provide 5 amps continuously without too much voltage sag, and for a 4xAA light you probably only need about 3 amps. Other brands may or may not be able to provide the power necessary for high-output lights. Also, Eneloops will last for years, and still provide the necessary power. Most other brands develop high internal resistance after not too long, and won't work in high-power applications. Either regular Eneloops or Eneloop Pros will work well. Get the Pros only if you need the extra run-time, though you'll sacrifice overall lifetime compared to the regulars.

As for alkalines in a high-power light. What were you thinking!!!! :eek:oo:
 

lightseeker2009

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Re: Extremely dissapointed with my new Fenix FD45

As for alkalines in a high-power light. What were you thinking!!!! :eek:oo:

No, someone else suggested it. I just did not fall for it. I have a broken laser distance meter, because of alkalines that leaked.
I even give away the free batteries that comes for the remotes of TV's etc. I only use NiMH's lately.

You quoted 3 Amps. Is this about what 900lm will consume while running off 4X AA's in my FD45?
 

etc

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Re: Extremely dissapointed with my new Fenix FD45

You did not say which type of chemistry you used.

Other people read it as Alkaline but I dont' see that directly mentioned.

If so, Alks are just not for performance.

NiMh are better - somewhat but still not the best there is. Case in point, laptops *used* to have battery packs made of NiMH cells and then switched to Li-ion. And that was a long time ago, maybe 15-20 years ago so it's not exactly "news".

to get something decent from NiMH, you need tons of them stacked up. Due to the low voltage.
 

WalkIntoTheLight

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Re: Extremely dissapointed with my new Fenix FD45

You quoted 3 Amps. Is this about what 900lm will consume while running off 4X AA's in my FD45?

Approximately, yes. It's probably around 2.5 amps, but it certainly wouldn't be more than 3. Depending on the driver, as the battery drains the current could go up (boost/buck), stay about the same (linear), or go down (simple resistor).
 

lightseeker2009

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Re: Extremely dissapointed with my new Fenix FD45

You did not say which type of chemistry you used.

Other people read it as Alkaline but I dont' see that directly mentioned.

If so, Alks are just not for performance.

NiMh are better - somewhat but still not the best there is. Case in point, laptops *used* to have battery packs made of NiMH cells and then switched to Li-ion. And that was a long time ago, maybe 15-20 years ago so it's not exactly "news".

to get something decent from NiMH, you need tons of them stacked up. Due to the low voltage.

I used Turnigy NiMH 2200 batteries.
I see Fenix recommend you must use their 14500 1.5V Li-ion batteries..
 

etc

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Re: Extremely dissapointed with my new Fenix FD45

Just forget NiMH for performance lights. I know many disagree but just go straight some to some Li-ions.

18650

17500 or 18500 or 16650, etc.

for max performance, use multiple cells.

e.g. I run 3x18650 in my Hound Dog Super.
 

WalkIntoTheLight

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Re: Extremely dissapointed with my new Fenix FD45

Just forget NiMH for performance lights. I know many disagree but just go straight some to some Li-ions.

As long as someone is familiar with proper lithium-ion safety, that's probably the right path. A single 18650 has about as much energy as four AA's, and can deliver it much faster.

But if someone is content with 1000 lumens, then a 4xAA light is just as capable as a 1000 lumen 18650 light. It will just be larger and heavier.
 

lightseeker2009

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Re: Extremely dissapointed with my new Fenix FD45

Guys, the flashlight was not the problem. It was inferior batteries. I took the 8 Eneloops I've charged this morning. It is now 20h26 as I posted this. I tested them all on my multimeter to select the four that retained the most power. But I could not choose. ALL 8 gave the same reading. 1.41V. simply amazing. To add, they must be at the very least be 6 years old. Well. Now the light enters turbo mode and stays there. Amazing. Fenix, thank you for the nice flashlight I could buy as a gift to myself:thumbsup:
 
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