TK20 battery drain?

Woods Walker

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In June I purchased a TK20 and have been using Duracell NiMH 2650 mAh batteries. Got them in a 4 pack the same time as the light and used the other two in my ZL H501 headlamps. Those don't seem to be having a problem but in the TK20 they are nearly dead within a week of none use. Noticed I was not getting good runtimes from the start but couldn't put my finger on the problem until I recharged them and placed these within the TK20 and didn't use it for 7 days. Couldn't even run the general mode right. Took the proven Duraloops from my L2D-Q5 and topping them off right now for a test. Guessing this will take a week to rule out the higher capacity standard Duracell's. Don't want to test this using alkaline batteries for obvious reasons. Just checking if anyone else ever had a constant fast drain on a TK20. Guess if the batteries are found to be at fault will ask about the performance of the 2650's in the battery section of CPF. I have used the same type in my GPS in the past and they worked for well.
 
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Marduke

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The TK20 has no parasitic drain, so the cause is most likely high self discharge of your cells.

How old are they? What do you use and how do you charge them?
 

Woods Walker

The Wood is cut, The Bacon is cooked, Now it’s tim
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The TK20 has no parasitic drain, so the cause is most likely high self discharge of your cells.

How old are they? What do you use and how do you charge them?



They were purchased in June of this year the same time I got the light. The two not used in the TK20 seem fine but naturally I recharged the 2xAA as a set for the TK20 as didn't want to have different levels of charge. I use an Energizer USB charger that has been working rather well for the rest of my lights. Been great for the L2D-Q5 using Duraloops and LSD Kodak AAs and AAAs. Also worked good using Energizer 900 mAh in my 1xAAA lights and headlamps. Clearly given the B&M charger and high cap none LSD NiMH the batteries can't be ruled out but then there is the issue of the other two batteries from the same package and recharged using the same charger working great in the headlamps. I don't have the extra cash for a better charger right now so guess if the proven Duraloops fail in the TK20 the next step would be a test with Lithium primaries as will never use Alkaline batteries for anything beyond an alarm clock.

I didn't think the TK20 had a parasitic drain but have read reports of other lights that drain batteries in short order when not in use (a week or so) and these were always defective lights. Somehow my gut says it is the batteries but wanted to see if anyone has ever had a defective TK20 that drain batteries when not in use. Overall I like the TK20 a great deal and if for some reason it has an issue I got it from Fenix store so not worried about repair/replacement as it is under the standard Fenix warrantee.
 

berry580

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Its normal. High capacity NiMH batteries discharge extremely quick. From experience, MUCH quicker than what's even claimed by the LSD ads thats trying to sell the LSD batteries

Duracell NiMH 2650 mAh batteries, i have EXACTLY that.
Charge it to 1.4V, and a few hrs it'll be 1.3xV.
Wait a few days and its 1.2xV and at that voltage, its next to no use when in high mode. It won't last long.
Get the eneloops or some other LSD batteries, they'll fair better.
 

zipplet

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I agree with all the previous posts. My TK20 is loaded with eneloops and it still worked last time I checked - and it had been charged about 6 months ago :)
 

Woods Walker

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I agree with all the previous posts. My TK20 is loaded with eneloops and it still worked last time I checked - and it had been charged about 6 months ago :)

It has been around 10 days with the Duraloops and so far it can run on Turbo/high just fine. Darn I am pissed at the 2650's as I had good luck in the past with these.:thumbsdow Well if everything is fine in another week I am done with High cap standard NiMH in total favor of LSD.
 

Dark Laser

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My "normal" NiMH's were once left for approximately 2 months in my TK20 (same with my E20) - there was no drain, and little self discharge. I think it still depends on how good the rechargeables are. Of course, there is a storage time beyond which LSD's are the clear winners, but since I couldn't let my lights lying around soo long...;)
 

dilbert

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I have had a TK20 in my desk for 7 months with eneloops that were charged 7+ months ago. I just tested it and it works fine. I keep a couple of boxes of alkaline AAs by it for backup though.
 

Cataract

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Didn't change the bateries in my TK20 yet. I've had it for about a month and used it for a few hours in total. It worked fine last night.
 
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