I have alot of Fenix lights and am considering buying the TK 70. The dealer I buy from in the US told me that he was told Fenix is working on a battery pack for the TK 70 to help with the battery problem. Can you give me any information about this improvement to the TK 70?
(Cathy's reply)
Dear Russell,
I am Cathy from Fenix China. In the beginning, TK70 is designed by using Ni-MH batteries and Fenix has made the relevant tests using Ni-MH batteries in various conditions to ensureTK70 perform well and actually so it does with Ni-MH batteries. It is true that TK70 had a defect when using Alkaline battery. The operating current is extremely high when TK70 works in turbo. However, alkaline batteries have the limitations in high-current discharging and TK70 has a very short runtime when powered by alkaline battery in turbo. Therefore, because of low-voltage protective function, TK70 will enter into high brightness level and lock it. The brightness selecting function can not work any more. But it has been solved. From Sep of last year, we revised the circuit and Alkaline battery can be used in it. Also TK70 work properly using Ni-MH battery.
(My follow up)
Thanks so much Cathy for the info. I guess my only question is if Fenix is working on coming out with a battery pack for the TK 70.
(Cathy's response)
Dear Russell,
The letter was returned and I have to send it through my private mailbox. The Ni-MH battery will be launched before March.
My take on this is that they are coming out with a battery only but they really did not give alot of information. Guess all we can do is keep our fingers crossed for something positive. Just thought some of you might be interested in their communication.
I didn't get that impression at all. I understand it is either their own battery or a battery pack for the existing TK 70. I just ordered a TK 70 but it is not here yet. Ordered from Shane and it is in the mail. According to him he spoke to Fenix and they told him they were coming out with something for the existing TK 70 so I guess time will tell.
Yeah I don't understand the battery-pack thing. Why is it difficult to use the batteries it was designed to work with?
I'd recommend AccuEvolution 10,000mAh low-self discharge ones, which is what I use with my TK70.
You also really want a SMART universal charger, as the normal ones will only charge about 3000mAh worth, because most cheap rechargable D batteries are REWRAPPED AAs, with the exact same capacity. Check out Rayovac, etc...they are all garbage! Therefore timer-based chargers only charge to that amount!
I got a Tenergy Universal Smart one with the USB port because it has LED charge indicators. It was about 30 bucks which wasn't bad.
If you have Eneloops or another good AA battery, you might consider getting converters, which take 2 AAs and put them into parallel to effectively make a 5000 mAh "D" battery. ONLY do this if you already have unused eneloops laying around.
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In any case, I cant imagine their battery pack being all that exciting. Theres no good lithium combination that will hit 6 volts and stay reasonably close to that, so I wouldn't expect them to use 2x26650s with a spacer or two. Hence they probably would literally wrap 4 NiMH batteries and provide some kind of cheap charger.
I agree with using high quality D Cells (Tenergy Premium D Cell 10,000) and charge them with my new Maha 808M if it ever gets here. I suppose Fenix is coming out with some D Cell's and a cheap charger as a package so those who don't want to go to much expense like I did will have an option. I just thought it all was interesting and will await the outcome.
hissing sound in Turbo is normal, sometimes it is louder, sometimes you need to put your ear closer to hear it.
I heard about adapter they are coming. A piece of metal that screwed into TK70, then it will be able to use TK75 battery tube configuration. So it will be 8.4V with 4*18650. Or you can extend to higher number of 18650 with more battery tube.
Why is it taking so long for them to release the adapter.
Note that this thread was necroed almost exactly 1 year. I would presume the battery pack for TK70 is overcome by events. The TK75 is meant for those that want LiIon batteries. They probably ditched the TK70 entirely… you might notice that in their latest brochure for lights that it is absent.
Due to very similar performance between TK70 and TK75, and upcoming RC40, TK70 will not be selling good. So Fenix might have decided TK70 to be obsolete in 2013. I wish they design another NIMH big light. TK70 is so reliable.
AA/C/D lights are particularly good for those who are not flashaholics. However, even as one, I would have the good sense to buy relatives and such more sensible lights.
I mean, whos gonna give away TK70s to their friends/relatives for xmas? Its too expensive and too unwieldy for general purpose usage. Anyone that actually needs that kind of power will already have an HID or something.
As such, they figure that anyone buying such a big light is gonna be a flashaholic and very likely to already have LI Ion batteries and stuff.
This does make sense to me and I can understand their logic. I bought my relatives an itp Polestar A6 years ago which uses 6 AAs and an MC-E. Tons of floody light, multiple levels, with reasonable size. Its a great light and they all love it and use it. It was also a reasonable price (70-80 bucks)