Spec me an LED Torch

[Aod]

Hmmm, 4.22 isn't a huge amount over, but if it starts creeping up i'd look into replacing the charger. you should try to keep an eye on them.

Lithium Ion cells are unpleasant when they go *poof*

In other news, my Dad told me that his Romisen RC-G2 died while he was in Atlanta, i have just bought him an Ultrafire UF-H2 (Zebralight clone) as a replacement

 

[mrk]

I will check the voltages after every charge from now just to make sure it's not overcharging by any worrying amount!

 

[molinari]

I'm about to buy a Zebralight H51 head torch (chosen over the H31) and I'm wondering about the batteries. Rather than use normal AA, would it be better to be using Eneloop AA batteries? Will these charge in a normal AA charging unit?

 

[Aod]

I'm about to buy a Zebralight H51 head torch (chosen over the H31) and I'm wondering about the batteries. Rather than use normal AA, would it be better to be using Eneloop AA batteries? Will these charge in a normal AA charging unit?

Easiest question first: yes, the eneloops will charge in a regular charger, but not all AA chargers are equal, if you dont have one look into the duracel CEF23, which CPF recommends as being quite a well behaved AA charger, especially for the money

as to whether using Eneloops over regular AAs would be better, well that depends on a number of things.
if the light is going to be stored up in case of emergencies, neither alkaline or AA are totally suitable, I'd recommend nothing but energizer lithium (L91) for that.


if you intend to use the light primarily on high or high-medium mode, you will see better runtimes out of the eneloops.
If you intend to use the light primarily on low or low-medium, you'll get better runtimes out of alkalines.


of course, with eneloops you always have the option of resorting to alkalines when ther run out.


remember that with alkalines there's always the risk of it leaking and coating your nice expensive light with corrosive goop. remember to never leave alkalines in lights for prolonged periods of time.


please feel free to ask more questions or for clarification, and congratulations on buying one of, (i feel) the best headlights in existance.

sorry about the stupid double spacing, my phone's acting up something awful...

 

[Deleted member 66701]

regardless of how a CC/CV charger operates, your description of the Li-Ion charging process is incorrect. if the charger uses the constant current until the cell reaches 4.2v and then reduces the current, it's effectively overcharging the cell.

I'm afraid you are wrong. It's that charge @ 4.2v but with a declining current that provides that last bit of charge - the last 15%. That's how a cc/cv charger works - simple as.

http://www.caplamp.org/Knowledge/images/partone-12.gif

Lithium-Ion cells should be charged fast for the first eighty percent or so of their capacity,

So constant current then?

and then charged at an increasingly slow rate for the remaining twenty percent of their capacity.

So constant voltage?

this is behaviour that i've been taught about at University and also that i have observed in the charging process on my laptop (a modern thinkpad with extremely precise charging circuitry - overall battery capacity hasn't dropped a single percent in two years)

What is your academic qualification if you don't mind me asking? I've been into RC models for 20 years and expensive flashlights and associated battery technologies for 4 yrs. I know how cc/cv chargers work and how lions should be charged.


Sorry if I sound like I'm being unduly argumentative but you're giving out bad advice regarding cells that can explode catastrophically if abused.


A very good link:-

http://www.caplamp.org/Knowledge/Charging_lithium-ion_batteries.htm

 

[Aod]

i have an Electrical Engineering Degree in Digital Forensics, as well as several years of experience with using Lithium batteries in airsoft and have seen two instances where a lithium-ion battery has exploded.

your insistence that the charge declines once the cell reaches 4.2V is simply incorrect. this implies that once the cell reaches 4.2v charging continues but at an increasingly sedate pace. can you not see that this is completely against the other things you are saying? at 4.2v, the Lithium cell is completely charged, and any further current being passed to it by the charger is overcharging it further?

 

[2StepSteve]

Not been here for a while other things going on and all that.. hmm.

I cast RESURRECTION on this thread!
been hanging about on CandlePowerForums recently and remembering 2StepSteve's Neutral-White Zebralight H51, I lost composure and splashed out on a custom-made P60-Dropin with an XP-G Q2 3000k 90CRI emitter, which finally arrived from North Carolina today

Nice warm dropin you got there AOD!

From a certain someone on CPF, I can imagine

Sometimes it isn't about max light output. Neutrals and warm LED lights are amazingly great. Too many people get caught up in the lumen race! Own a neutral or warm light and you will realise it isn't all about light output.

After charge was 4.22v for one and 4.16v for the other. Did I mention how bright they are?

As Aod said..watch that charger Khaaan. 4.22v is over the recommended safety limit of a Lithium-Ion cell. Buying budget cells is one thing I do.. but don't skimp on the charger unless you watch it like a hawk. You should consider the Pila Charger.. seriously I near enough trust my life with it. It stops bang on 4.2v every time.

What brand of cells are you using?

I'm about to buy a Zebralight H51 head torch (chosen over the H31) and I'm wondering about the batteries. Rather than use normal AA, would it be better to be using Eneloop AA batteries? Will these charge in a normal AA charging unit?

Eneloops would be the best option. But any NiMH (rechargeable battery) would be much better over a normal (alkaline) battery. NiMH batteries are able to deliver more current than what alkaline batteries are able to - giving you more from your light.

What charger do you have? Make model?

 

[Deleted member 66701]

i have an Electrical Engineering Degree in Digital Forensics, as well as several years of experience with using Lithium batteries in airsoft and have seen two instances where a lithium-ion battery has exploded.

your insistence that the charge declines once the cell reaches 4.2V is simply incorrect. this implies that once the cell reaches 4.2v charging continues but at an increasingly sedate pace. can you not see that this is completely against the other things you are saying?

It doesn't contradict anything I've said at all - care to provide examples? Did you not look at the graph I linked? Are you saying it is incorrect?

at 4.2v, the Lithium cell is completely charged,?

No, it isn't fully charged. I cannot believe such a statement is being made by someone with a degree in electrical engineering How can you have such a fundamental misunderstanding of the relationship between potential and capacity?

and have seen two instances where a lithium-ion battery has exploded.

Yes, I can well imagine!

 

[2StepSteve]

4.2v from what I understand is persevered as the limit with respect to strike the ultimate balance between cell cycle life and stability.

Not to say that 4.3v will make the cell burst into flames but anything over 4.2v is likely to have an impact on that cells overall life - in terms of discharge/charge cycles.

 

[Aod]

No, it isn't fully charged. I cannot believe such a statement is being made by someone with a degree in electrical engineering How can you have such a fundamental misunderstanding of the relationship between potential and capacity?

I've been doing a substantial amount of reading over the past few hours. it seems that I was wrong, and you're definitely correct. Were i still in University i'd now go and give my lecturer a right bollocking, but i can't so i wont.

A Combination of an incorrect teacher and a few flawed graphs is a dangerous thing! I thank you for being rational and sensible about this, i'm sorry it's taken me this long to realise you were right.

Yes, I can well imagine!

I wasn't the one doing the charging

 

[Deleted member 66701]

I've been doing a substantial amount of reading over the past few hours. it seems that I was wrong, and you're definitely correct.

Hey no problem - your due big respect for admiting you were incorrect - something we seldom see on these forums.

I hope you didn't think I was coming across as too strong or argumentative but as we both know, li-ions are volatile and I didn't want someone to make a mistake charging or discharging them.

Oh, and I've also seen a li-ion cell explode - I shorted a cell and threw it into a metal bucket to see what would hapen - very impressive!


To show we're all still friends, have you got your eye on any new torches? For me personally the last one I bought was a ShiningBeam S-Mini - great light. Nothing else seems to have happened development wise - xm-l's have been out for ages now. Maybe it's because we're in the "daylight" season - a lot of new torches wont get relased until it starts getting dark again at the end of September.

 

[Aod]

Hey no problem - your due big respect for admiting you were incorrect - something we seldom see on these forums.

I hope you didn't think I was coming across as too strong or argumentative but as we both know, li-ions are volatile and I didn't want someone to make a mistake charging or discharging them.

Oh, and I've also seen a li-ion cell explode - I shorted a cell and threw it into a metal bucket to see what would hapen - very impressive!

Thanks, and i think you were absolutely right to press the issue, Li-Ions are evil little buggers when mistreated.

Tell you what, the thing that sticks with me from those Li-Ion explosions is the smell - that sort of sweetish fruity-smell. really really creepy!
Apparently it's due to the esters that the Li-Ion electrolyte is composed of...

I'm trying to avoid buying any new lights at the moment, i've spent almost £150 in the last two months on lights, most recently i bought a Surefire C2 from america which will house my Nailbender Warm-Dropin semi-permanently. just dying to have the thing arrive now, it'll be my first *proper* high-end light.

i just bought a new light for my Dad from Hong Kong, who knows how long that will take to arrive though
One of these:

should be nice

 

[Aod]

Oooops, this turned up this morning:

This means the light was made in about 2005.

it's Magnificent!.

 

[Radiation]

Can you get any nice warm led touches for under £40?

 

[mrk]

Can you get any nice warm led touches for under £40?

Warm as in the colour tint?

I have a brand new warm tinted XM-L P60 drop in if that's of interest to you? All you'd have to do is buy a host such as a SolarForce L2 which will cost £15~ and of course a battery

 

[Aod]

Warm as in the colour tint?

I have a brand new warm tinted XM-L P60 drop in if that's of interest to you? All you'd have to do is buy a host such as a SolarForce L2 which will cost £15~ and of course a battery

you mean your one you posted about up above? that's not a warm Tint Khaaaaan

Can you get any nice warm led touches for under £40?

Other than price, do you have any preferences? brightness? size? weight? Battery choice? (AAs, CR123A's, 18650-rechargeables?)

 

[mrk]

Well it's slightly warm

He can have it if he gets a host! I consider it an accessory to the orange peel reflector and at £11 odd it was worth it I guess!

 

[Aod]

hehehe, i know what you mean

it's a shame that China's let you down Khaaan, but a true warm-white LED is a sight to behold. it's like everything's right in the world when you light one up...

it's kind of strange come to think of it.

Re. Warm light for Radiation:
There aren't a huge amount of ready-made/production lights with Warm-tint emitters. most of the warm lights on the market are aftermarket mods or assembled from components, like a Light-module + body etc.

i bought my warm-module from a very very good guy on CandlePowerForums for about $40 (us). i'd be happy to give you more info if you think you'd be interested in that sort of thing.

It's the one i talked about Here.

 

[sHo0sH]

Hey guys, just ordered one of these...

Thought I would share at the bargain price!!

http://www.kickstarter.com/projects/527051507/hexbright-an-open-source-light

 

[Aod]

an interesting concept but the light itself looks a bit crummy. i have an XM-L light that does 800, 100 and 0 lumens, no annoying blinky

and it only cost me $32