what rechargable batteries should i order for fenix tk10

bigfish5

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I am trying to figure out exactly what i need to order for a tk10 , i have no experience with cr123a batteries. I bought a fenix l2d premium, it makes 180 lumens with just 2 aa batteries, now i want the tk10 with 225 lumens. This might be addictive. I want recharchables. help please.
 
I've had good results in my TK-10 with these cheapies from Deal Extreme - will deliver at least 35 continuous minutes of run-time at full power (haven't tested them beyond this point), and they seem to recharge fully. Only significant disadvantage is that the diameter of the case varies somewhat from unit to unit - can make for a tight fit.
 
I'm not sure if recommending UNPROTECTED cells for someone who says: "i have no experience with cr123a batteries" is a good thing? Does anyone know if protected cells will fit?

bigfish5: Welcome to CPF. Unlike common alkaline batteries like AAs, Cs and Ds, Li-Ion rechargables take a certain amount of knowledge to use safely. The link to battery university is a good place to start.
 
protected cells will very unlikley fit, my tk10 is at home at the moment,but i think that regular CR123A cells fit flush with the end of the body, so protected would prevent the tail from even screwing on.

Its not that bad starting with un-protected, just remember to charge every day to top it off, and you should do fine. besides its 6$ for 4 batteries at DX, not a huge loss if you do accidently over discharge a set

Crenshaw
 
Its not that bad starting with un-protected, just remember to charge every day to top it off

Li-ion cells only need to be recharged after they've been discharged - Self-discharge is insignificant, so there is no daily recharge or "topping off" necessary.

Best strategy with unprotected Li-ion cells is to simply restrict your flashlight's run-time to somewhat less than the batteries' safe amount - 30 minutes is probably a safe value for 800 mAH RCR123's in a TK-10 when running at full brightness. If you need full brightness for more than 30 minutes, swap in a fresh set of batteries every 30 minutes.
 
PR123A will def not fit in the Tk10..

Skibane, what i meant was, assuming you use your Tk10 at least some-what everyday, then topping of the batteries everyday ensures that the next day you are going out with a full pack..:)

Crenshaw
 
FYI - My AW protected 750mAH R123 cells fit just fine, not too snug.

55 mins on high until protection cuts in.
 
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Li-ion cells only need to be recharged after they've been discharged - Self-discharge is insignificant, so there is no daily recharge or "topping off" necessary.

Best strategy with unprotected Li-ion cells is to simply restrict your flashlight's run-time to somewhat less than the batteries' safe amount - 30 minutes is probably a safe value for 800 mAH RCR123's in a TK-10 when running at full brightness. If you need full brightness for more than 30 minutes, swap in a fresh set of batteries every 30 minutes.
That is not good advice. Li-Ion cells perform better if they are topped off frequently, rather than fully discharged before recharging.
 
While it's true that self-discharge is insignificant with Li-ion, I also took Crenshaw's post to mean that you would do well to top off your cells after a medium amount of use, or after a few short uses. No reason to let them discharge significantly before recharging, other than the minor amount of effort recharging takes. Better safe than not.

I was not as concerned about running a cell down to where it had to be disposed of, only a minor cost - I'll agree with that. I was concerned that an overly depleted cell may ruin a nice light, or someone's day, with the small but present chance of a venting incident after overly depleted cells are recharged. If the AW protected 750mAh RCR123 cells fit, I would strongly recommend them for the TK-10.
 
My random thoughts...

I use unprotected DX cells in my 6P, but I am retentive and NEVER let them fully discharge. Excessively discharging the cells increases the risk of polarity reversal and an explosive condition/electrical fire can result if one cell reverses polarity relative to another.

I run them for 40 minutes MAX and replace them, even if they appear to have plenty of life left. I already know the emitter will dim and turn yellow around 50 Minutes. I also number each of my cells, and match them for run time as close as I can and ONLY use them in matched pairs. Use a good cut-off charger that cuts charge at 4.2V, and top them off as needed. To my surprise the self discharge has been very low, even though they are not supposed to be LSD cells. If I fully charge them, and let them sit in my pack for a couple weeks they will top off in about 20 seconds... pleasant surprise.

Its a lot of work, but IMHO thats part of the hobby.

I also have some trustfire protecteds, that work great and are worth the added peace of mind, so long as you plan ahead for the added 2.5mm cell length. Just run them worry free till they die and don't even think twice about it.:thumbsup:
 
I agree that if you practice ALL the safe procedures that kramer5150 does ALL the time than you can enjoy the lower cost and possible extra mAh of the unprotected cells. I just think few people should start with those cells.

Even his last paragraph starts:
"I also have some trustfire protecteds, that work great and are worth the added peace of mind"
IMHO, this is where most people will be better off.
 
I've been using DX cheapos
http://www.dealextreme.com/details.dx/sku.2086
for mine, 55mins runtime on high until flickering notifies of low voltage of batteries. Then I switch to another pair. No probs so far
1. Ultrafire cells have a very bad record of unreliablility
2. They are unprotected cells
3. You are fully discharging them each time

In other words, what you are doing is the exact opposite of what experienced members have recommended here.
 
1. Ultrafire cells have a very bad record of unreliablility
2. They are unprotected cells
3. You are fully discharging them each time

In other words, what you are doing is the exact opposite of what experienced members have recommended here.

Why do you think they are $6.66???

666 = :poof:
 
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