Are the lithium batteries sold with lights safe/UV light discussion

You have restored my faith in giving it a fair shake once it arrives :slight_smile:

Thanks for chiming in, I don’t think anymore needs to be said as that is the best explanation

Lots of interesting information.
For now i am sticking to just this light purchase but if i look for more lights in the future i will look at the SC31 Pro again.

Check out the Wurkkos TS21, now that’s an excellent EDC option. I’m just editing my review

Please toss a link in this thread once its up :slight_smile:

How about just clicking on the link in my signature and bookmarking my channel

Too complicated :smiley:

I won’t be posting a link, but I will create a new thread for it

Thanks Funtastic, I have been debating on getting a YR1035R for quite a while - I don’t believe I will use it very often.

I am very aware your testing on LR2170SD showing it outperforms 50E. However, current version 50E2 is much better than 50E and performs as good as 50G according to Mooch’s testing. I actually bought some 50E2 from 18650batterystore in April @ $4.49 each so I didn’t see any reason for getting LR2170SD.

Actually Lishen LR2170LA is a quite interesting cell with 4000mAh/35A CDR, but again it priced higher than Molicel P42a so obviously P42a is a much better choice.

What is the advantage of Wurkkos TS21 over sofirn IF25a at same price? TS21 has a smaller head so heat dissipation will be even worse than if25a. Included 21700 is obviously a Lishen LR2170SD but I wonder how long 3500LM could last with 9.6A CDR. ATR kicks in at 45oC - does it have a regulated driver?

Not sure why everyone is so focused on lumens for a small EDC where you don’t usually activate Turbo for very long. I personally grab a larger model if I need that much output and range.

70°C limit and it achieved over 60 sec Turbo - Head 63°C - Body 54°C after 15 min. Something close to that, currently on the loo lol.

TS21

- Compact

- 2 way clip

- Magnetic Tailcap

- Better flood

  • Nicer looking beam profile

Some find the IF25A to not offer enough flood, looks bad, no thought went into the design it seems. Yes, it’s better at holding Turbo, but I would rather the above for an EDC option

Don’t buy with their battery, I use a Molicel P42A

ANSI

IF25A - 3,040 lumens
TS21 - 2,800

Not much difference considering the TS21 only has 3 LEDs

Bit disappointing that they used a Fet driver when they told us on here it was running a buck.

I would like to add that the older Convoy S2+ uses Nichia 276A emitter with Optical Power Typ. 780mW, whereas the upgraded S2+ uses Nichia 276C with Optical Power Typ. 1050mW, although the size remained the same. It is also slightly more focused (120 degree vs 130 degree). But efficiency improved a lot. Assuming a forward V of 4.4v and forward C of 0.5A and a output of 1.05W, the efficiency is 1.05/(4.4×0.5) = 47.7. So the newer 276C emitter is ~50 efficient, half of the energy it uses for UV light and half for heat. It is quite significant upgrade.

Thanks a lot Funtastic, FET driver and the lie from wurkkos really pissed me off. if25a 4000k is actually floody enough for me. I think SP35 is the same size as TS21 but beam is too focused.

Good point, I wasn't aware of that. Just compared the datasheets and it looks like they made an effort to improve the die for better heat transfer and lower junction temperature (rated at 3.25W power dissipation now), and it looks like the bins demand a little less Vf now as well. Puts it more on par with the LG I think although they still officially list the other heat-related parameters the same as the 276A...makes me wonder if it can actually handle a little more current/overdriving better or not. The derating is only slightly better than before, but really that's an achilles' heel for all of these UV emitters, especially the way we're using them in flashlight hosts.

Realized that they didn’t lie about it, we just misunderstood. Wurkkos said it was FET + Buck which means buck for the charging circuit and FET for the light itself.

Thanks for the link, watching now.