Protected 18650, meaning of "PCB is tripped" ?

Batteries and Chargers Rechargeable Batteries
33

I have the exact same headlamp and it drains the cells below 2v.

This hasn’t been my experience. I’ve had many flashlights with no low voltage protection discharge under 2v

2.5v on load should be the absolute minimum but not all batteries, you need to check the datasheet for each model. The reviewer HJK has stated that he no longer runs tests down to 2.5v anymore due to ruining some batteries, he now only tests to 2.8v.

I do however just immediately switch off a light once it goes dim. If you leave it on once it’s dim it’ll very quickly drop too low.

Do not attempt to charge a battery that’s under 2v unless you know what you’re doing.

Did you get that? safety wise, not ruling out damaging your batteries irreversibly.

34

Since you are carrying the spare battery, why not carry it in a flashlight with Anduril UI? Then you can check the approximate voltage of the battery you are using by putting it in the flashlight. Just make sure to lock it out so it does not come on in your pack/pocket when hiking. Really, it is not difficult to click three times, I do it often and have no issues, trust me. And you have another flashlight available as a backup or to use around camp. I always carry a backup light… one is none and two is one, etc.

And yes, if both batteries get down to 3.4V anyone would run them down on an overnight trip. But that is something that has not happened to me. On a longer trip, carry more batteries. Then you can relax and enjoy the outdoors.

35

I just don’t know why someone would risk using those cheap batteries, they are a safety risk, period.

Years ago I saw a thread on BLF of a SkyRay flashlight literally explode which blew out his apartment windows. This was a result of using the cheap Chinese cells it came with.

I’ve seen multiple stories of Chinese cells catching fire, smoking, exploding. Just don’t use them, purchase something decent such as LG, Sony, Samsung, Panasonic etc

36

I’ve even seen some covered in rust when I removed the shrink wrap for my RC heli.

37

Same for lights that take (non-rechargeable and nominal 3v) CR123A as well as (rechargeable and nominal 3.6v) 16340. Some models do have LV warning and/or cutoff for rechargeables, but the LVP is defeated if the battery is reconnected when its voltage is lower than about 3.3v. The driver resets and assumes it has the lower voltage non-rechargeable, which of course can be safely driven into the ground.

38

Is there any kind of required standard compliance to prevent such an irresponsible design?!?

Or maybe any flashlight that has a LED displaying red when the battery is low could also do the job? I am not sure if my next flashlight would have Anduril UI.

Simple by ignorance. I ordered that headlamp on eBay end Jan 2020. At that time, I was vaguely aware that I should use genuine brand name 18650 cells. I just ordered those 2 cheap cells anyway, at least I could use the headlamp right away. In fact, I think most customers, myself included would feel happy as they have no way to know to judge the quality of the products.

Thanks goodness I got educated now thanks to BLF members. And the reason was pretty silly, I was looking for a way to disable the next memory mode in my other eBay flashlight. That was then I discovered a whole world of better designed flashlight and in particular about the Li-ion cells. Here’s another example of benefit I had learnt thanks to the BLFers. I bought some DC-Fix Diffusion Film , just to playaround. I put a diffusion film and an orange filter on a cheap ebay flashlight. And miracle, the ugly beam is transformed into a nice warm light without any hard hotspot.

So now my solution is simple. I’ll give up on those cheap 18650 cells and that F&^%! headlamp. Or maybe keep it around as backup. The winter is over now, the evening walk is not that dark. I have almost a year to order a multimeter, brand name cells & headlights.

39

no
use of unprotected LiIon requires an educated operator

as moderator007 pointed out, there will be no built in LVP in most lights that are dual fuel, that is, a light that can use either a primary or a LiIon, will not prevent overdischarge of the LiIon, because primaries get used to lower voltage levels than LiIon.

for those reasons it is recommended to use Protected LiIon in unprotected lights.

even so, an educated operator, can use unprotected LiIon, IF the operator takes responsibility to monitor Voltage.

now the granny scenario
I lend a light to granny, that has no LVP, and is loaded with unprotected LiIon.
she falls asleep with the light on, and it overdischarges the cell…
IF the cell is INR or IMR, odds are good there will be no Venting with Fire, upon recharge

but in the interest of safety, recharge in a fireproof location, and remain present to monitor the charging cycle, to ensure the battery does not overheat

Do NOT put LiIon on charge overnight, while you are sleeping…

40

I heard that they’re chargers that will revive a dead battery? I know my Opus doesn’t do it. Wonder if that feature does work ok and does it really bring back dead batteries?

41

The "better" chargers I got don't revive a dead cell but some cheap ones do. A bench Power Supply is better to use for reviving them - limit the voltage - just couple secs sometimes.

42

My Olight Universal Charger has had no problem recharging a protected 16340 cell that has tripped protection, and reads 0 volts. (the battery is not really at 0 volts when that happens, its just blown the fuse)

The fuse did reset, and the battery started charging normally. After a few seconds I disconnected from the charger, and tested the Voltage of the battery with my DMM, which showed it was above 2.7v.

===
doing another test now, to intentionally trigger protection

16340 w built in USB
ran it in an Astrolux S41 on maximum
started out reaching 400 lumens when battery was at 3.6v
after a few seconds, the light stepped down to about 200 lumens, and I then bumped it back up

after doing that a couple times
it stepped down to 40 lumens and would go no higher,
at that point the battery tested at 2.9v

I could not make that light blow the protection by trying to force it to give me maximum mode, it just kept stepping down and getting dimmer

since I wanted to trip the protection, I put the already depleted 2.9v LiIon in a different light and cranked it up to maximum… it produced 140 lumens (on a full charge it does over 400), and a few seconds later the light turned off completely.

I have a dead battery. It reads 0 Volts, and will not work at all, in any light.

Protection tripped.

I plugged in the mini usb charge port on the battery, and counted to 10, then took it off and tested with my DMM.

The battery reads 3.0 volts

I plugged it back in to its built in USB charging port, and it is continuing to charge normally.

===
conclusion
the Astrolux S41 has a step down system built in, that prevented the protection from tripping

my Jetbeam RRT-01 Rotary has no step down system, it just gets dimmer, but when I try to use maximum power, it trips protection and leaves me suddenly in the dark.

Both the Olight Universal Charger, and the built in USB charging port in my 16340 battery, have no problem recharging a LiIon that reads 0 volts after tripping protection.

a couple of details to consider
Using a Protected cell in the RRT-01 can result in the flashlight suddenly turning off completely. This happens when the battery is below 2.9v and the maximum output has dropped to 35% of initial maximum, on a fresh battery.

Since I have a light meter, I often use it to check the maximum output on RRT-01, which is my EDC, instead of opening the light to check battery voltage.

I have learned that when the max falls below 50% lumen output, it is wise to replace the cell with a fresh one, and recharge the one coming out.

IF instead of using protected cells in the RRT-01, I use UnProtected, then the light drops below 50 lumens in brightness, as battery falls below 3.0v. It is then up to me to replace the battery, before the output is so low as to be unuseable.

The UnProtected batteries I use are IMR and INR, they are safer than ICR, which I would avoid unless protected.

Moral of the story
Protection can be tripped by turning the light up when it gets dim (in my RRT-01, but not in the Astrolux S41)

43

Would the Panasonic (or Sanyo?) NCR18650GA as safe as the INR? I know that those NCR18650GA can support 10A continuous draw. Which I don’t need. I am looking for better safety.

44

according to this your battery is unprotected NCR chemistry

and according to this it is not as dangerous as ICR chemistry

> I am looking for better safety.
you would need to define your use case risk
for example
any chance you would leave the light on, unattended?
if yes, then you might be better off with a Protected battery, or a flashlight with built in Low Voltage Protection (LVP), that will turn the light completely OFF below a certain voltage… (not just dimming, not just a warning light)

bear in mind that some lights such as Klarus, will claim their light has Low Voltage Protection, when in fact it is just a low voltage warning… this might be a flashing event. That requires that the operator is awake, and able to respond appropriately to the warning.

I applaud your efforts to learn safe practices.

45

Sofirn’s D25S & SP40 headlamp are decent with low voltage protection

If I was you I’d just get a good brand 18650 and continue to use your headlamp. Switch it off once it dims or use a protected battery

46

I think the NCR18650GA battery he is considering buying, is a good battery, though I dont really understand all the details of this review:

I know nothing about the batteries he presently has.
And even less about the light that started this educational $eminar

47

Will do both, planning to buy Sofirn SP40 + good 18650 cells. Current headlamp and its cells would be used as backup and experimentation.

There are several brands and models of 18650 cells. Among those, there has to be one which is safer than others. Maybe that model is not powerful, or cannot sustain high load, but it is relatively safer. That the “safety” I meant. I could order from 18650canada.com but the vendor seems clueless about his products so I prefer the Convoy store on AE (b/c I need to buy an S2+ too). In this store, the 2 unprotected are Samsung INR18650-35E and Panasonic NCR18650GA. Which one would you pick?

Edit: reading the forum post link you gave NCR vs IMR battery - any difference? It looks like NCR is better: quoteing the answer here for convenience:

48

if one is safer, it is probably due to the chemistry, not the brand

but I challenge you to define the type of safety you are in need of

for some, safety refers to the battery being able to deliver a lot of power, fast… vaping people use that kind of “safety”

but I dont think it applies to your headlamp use

I think your use has a primary risk of overdischarge, even at very low rates… the key is to get the battery, or the light, to turn completely OFF, before overdischarging

so in your shoes, I would focus on Protected Batteries, or Protected lights.

a Protected Battery, can be “unsafe”, if used in a light that can trigger the protection circuit and leave you suddenly in the dark. So again, which light you use with a protected battery, matters…

that is why I suggest focusing on your use case risk scenario, and that is why I caution you to have a protective strategy that addresses the granny fell asleep with the light on, scenario

so now Ive given you two specific failure cases that apply to your headlamp

  1. it overdrains the battery when left on accidentally
  2. a protected cell can leave you suddenly in the dark, in a place where that could be dangerous…

soon you will develop your own comfort level and will decide which use case scenario is your primary concern…

for me, using a protected battery in an RRT-01, would protect against overdischarge if I fall asleep with the light on… otoh, it would put me at risk of sudden darkness… My solution is to carry a spare battery, within reach, for the latter scenario, or use an unprotected cell. But that does not protect from overdischarge if Im unaware the light is running unattended.

from where you are now
the next step is to get a tool that can inform you of battery voltage
then do a rundown test
for example
set a 30 minute timer, and run the light down, plotting voltage at each 30 minute interval
when you “notice” the light get dimmer than “normal”, note the voltage…

that will give you a “map” of the voltages you can keep using the battery at, and the voltage at which it is a good idea to replace the cell…

49

This is one of, maybe the best, protected cell on the market: https://liionwholesale.com/collections/batteries/products/protected-panasonic-sanyo-ncr18650ga-button-top?variant=12534255236

Jon at Liionwholesale knows his batteries. Check out the description and specs on the protection circuit on that page. If I was into protected batteries, this is the one I'd buy. The better PC designs also have lower resistance so you don't lose much in performance (amps).

I do have a set of these, but from like 3 years ago, and they've been improved upon since then.

50

Oh I get it now. I was more thinking about the safety related to the Li-ion cell like burning or exploding. You meant a more general safely for both the cell and related to the usage.

I don’t do rock climbing in the dark so if the light goes dark for any reason. I have plenty of time to switch to the backup light. Neither I have any needing for “a lot of power, fast”.

The risk related to the light being turned on unintentionally, this could happen but I will make sure this would be almost impossible. In the unlikely event this happens, well, the cell is dead and I will buy another one. At the beginning of this thread, I was concerned that the LED could run the cell below 2.5V without any visible effect (analogy with a gas tank). But it turns out common sense is enough to avoid the troubles. Just to be overkill on the safe side, I would switch to a protected light. Planning on Sofirn SP40 and brand name cells.

After I buy multimeter, new cells. I will definitely do this to get acquainted with the equipment.

51

all of those things

overdischarge leads to burning or exploding when recharging

repeatedly triggering Turbo demand after step downs is a recipe for overdischarge… this is a typical behavior for some untrained operators

different battery chemistries produce different maximum output capabilities

both batteries in these photos are UNprotected so neither will produce sudden darkness,
both lights were fired on Maximum to measure their output

different lights have different maximum output capabilities, that still vary by battery chemistry

IF you are reasonable in your demand for Lumens (define reasonable as, sustainable for an hour, an output of not more than 400 lumens…), then issues about high discharge rate batteries, are as you said, not relevant to your use scenario.

otoh, if you insist on hitting the Bear with Turbo, over and over, expect your battery to be toast before long… you will be too… lol

52

There's a usage scenario many of our firmware designs were intended for - what if you are in a pitch black cave on your last cell, you would want to get as many minutes out of it as you can, so the idea is keep stepping it down and never shut it off. Of course LED's have a minimum voltage requirement so there are limits, but again, point is to extend output of light, any amount of light as long as you can. I think this was originated by Dr. Jones.