And you probably won’t know what you are getting either - which is why I don’t own any protected batteries. Over and Under voltage protection is fine, as is reverse protection, but I don’t want a battery that will cut out at an unspecified current, or unknown temperature, without warning.
Based on what I’ve read in Cree’s LM80 testing (which tests LED lifetimes), it seems heat is the largest factor in determining LED lifetime, and current is a distant second. At least, within normal ranges. The LED junction point can handle temperatures of 85C-100C okay, but beyond that they start to age the LED prematurely.
No doubt over-driving the LED will cause it some additional aging, but is 20,000 hours or even 10,000 hours so bad? How often are you going to be running the LED at high output? 10,000 hours will require about 10,000 full battery cycles. Even if you drained the batteries in your light each and every night, it would still last 27 years until it dimmed to the 70% threshold. I doubt you’ll still be using the light 27 years from now.
That’s not true. The key is to know what your buying and not to buy just any old protected cell.
Stores like https://liionwholesale.com and www.mtnelectronics.com give detailed info on the protection circuit of each battery. Keeppower also gives specifics on their protection circuitry. Also, you have certain light companies that add their own protection circuitry to cells such as Imalent. They have a protected version of the Samsung 30Q rated at 15A. (I forgot about this one until just now). Plus I’m sure theres a lot more I don’t know about.
As good as stores such as Banggood and Gearbest are, I would not recommend buying protected cells from them. They are so large that their stock is always being replenished and might be replaced with a slightly different protection circuit added on that has different specs. The store may not even realize the product has changed slightly.
joechina - YES: excellent idea.
click = RAMPING
2 clicks = MODES
Today it’s reversed.
Only for the reason RAMPING is mostly used and people try to switch off the lamp if it starts blinking.
I believe that will fix the only issue I have with the light. I believe in previous posts I have said the issue is being able to easily entering flashing mode and hard to get out. It is more intuitive to press the button and get ramping.
Please, don’t start on easy and hard. As I have also stated THIS IS INDEED THE FLASHLIGHT I WANTED. I HAVE FOLLOWED THE DEVELOPMENT FROM PRETTY MUCH THE BEGINNING. I bought them when everything was well known.
I did not pay close enough attention to the impact of the actual press sequences when NARSIL was being created. Even if I had paid more attention, I probably would have missed the impact of sequence I view as a problem.
The team did an incredible piece of work. It just needs to be a teeny bit more user friendly (I am talking only about the two button sequences) for sale on the open market. And that may well become the majority of the sales volume.
Contrary to some opinions, I am not an idiot (at least I think so). I am interested in some of the other functions in NARSIL. But not for a civilian, as it currently works.
An additional feature of getting a protected cell is that you will have a button on the positive end. You can find unprotected cells with buttons.
The button is useful for getting full contact in some lights, and probably chargers.
alternety
You can ask in a separate thread if somebody near you can change the firmware to your liking.
Maybe Toykeeper if you ship the lights to her.
Hi, I just received my BLF Q8, bought from banggood. It is all good except I noticed a bubble in one of the led. Is this normal? I never seen anything like this in my other torchlights. I am worried it affects output and more importantly, if it is a defect, cause a premature lifespan of my torchlight.
As shown in the picture, the bubble is quite small but very visible with naked eye, especially in moon mode. On the camera, it is harder to spot so I drew a red arrow.
Can anyone tell me what is this and should I be worried? Thanks
Click on the picture for larger view
Link to imgur: blf q8 - Album on Imgur
PS: Not sure if this is the right place to post. Please advise if this is the wrong thread.
Welcome to BLF jstay!
Is it a bubble as you say, or a black spot (as it looks like in the picture)? Perhaps you can take a picture with the light off?
If it is a clear bubble on the led dome it does not absorb light and warm up, so it does not have to affect the lifetime of the led. But you never know. Bubbles on the led dome are sometimes caused by a hot solder iron slightly touching it.
Hi djozz,
thanks for your quick response. Yeah, I am quite concerned about this so I created a blf account to ask more about it. 
It seems to be a bubble rather than a black spot. With the light off, it (the bubble) cannot be seen with the naked eye. On camera I am quite certain it is not possible as well.
when the light gets brighter as it is ramped up, the bubble cannot be seen as well as the light blinds it out. So, the bubble can only be seen in moon mode.
How serious is this issue, should I contact banggood? Or is this a non-issue which does not affect lifespan and performance?
thank you
This sounds like a completely new issue that nobody has ever heard of before. One would assume that Cree would have noticed that before selling the led.
What can you do though? I doubt banggood would allow you to return it because of that. Maybe you can use turbo quite a bit and see if the LED burns up or not. If it burns up within the warranty period then you could have it replaced. If it survives, then it likely won’t cause any problems later on.
I’m afraid that for the seller it is a non-issue until the led blows up, there is no way you can convince them that that tiny black spot is the start of a dying led. The best you can do I think, is do a test run on highest settting, when the light steps down after three minutes, ramp up to highest again and let the light get as hot as you can still touch it. If the led blows you have a case for Banggood, if it doesn’t you will have to live with a bubble in your led and some uncertainty.
Alright thanks JasonWW and djozz. How long /how many cycles should I let it run on turbo?
okay thanks ThrowMeInToDarkness. Yeah you happened to answer my question just as I was typing it!
Your bubble might also be just a tiny drop of flux which could easily be removed with Isopropylalcohol instead of completely destroying the LED.
@ Flashy Mike Yes that might be the case as well (hopefully) thanks for the idea.
Will dipping a cotton bud (also known as q-tip, ear cleaner etc) in 99% ipa and then lightly wiping the led dome do the trick without damaging?
sounds good, you will not destroy anything like that. Make sure that no cotton fibers are left behind on the dome, that can burn again by the heat of the very dense radiation.
Okay , will try that. Thanks for the idea
Probably yes, but don’t touch the front of the reflector. I strongly suggest to remove the reflector before cleaning.
Q-Tip is perfect.
ok thank you for the response.
to remove the reflector for blf q8, I just need to unscrew the top portion (silver aluminum ring, o ring , glass) and the reflector can be pulled upwards directly?
or do I need to unscrew the bottom including the driver circuits etc. ?
I’m afraid that you need to go all the way. Everything comes apart fine but this is it:
First unscrew the silver SS ring and remove the glass and large o-ring. Turn the head around.
Unscrew the driver and tilt it until you can get past it with a screwdriver. Inside the driver cavity first unscrew the big central screw then the two small screws. Then the reflector should fall down. Clean the led and reverse for assembly, take care to seat the reflector precisely on the the plastic centering rings around the led before tightening the screws in the driver cavity.