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Thread: Ultrafire 18650 3000mA exploded

  1. #121
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    Default Re: Ultrafire 18650 3000mA exploded

    Quote Originally Posted by Anzycpethian View Post
    I don't know where else to post it but I have a question: When a lithium cell explodes inside a flashlight, isn't the aluminum tube / body of the flashlight enough armor to your hand to prevent most dangerous injuries?
    Where can I find more information about what happens when a cell explodes inside a flashlight, like does the body explode in splitters or strongly dents?
    It is not really the cell exploding that causes the light to explode, it is a build up of pressure from the cell venting gases.

    In fact it is the inherent strength of the lights that results in such violent explosions when the happen. The strength allows a massive pressure to build up before catastrophic failure.

    Li-ions are really not as unsafe as you might think reading this forum. Think of the number of aircraft crashes and car crashes that are reported and how many journeys are made. The actual number of problems are very small and require quite serious abuse of the cells.

    Leaving cells in chargers unattended and overnight can result in serious overcharging and then using those cells in multi cell lights and leaving the light on until the cells are dead and effectively short circuited is asking for trouble.

    If you monitor your cells voltage before and after charging and make sure you use similar age/condition cells in a multi cell light and if using unprotected cells, stop using the light when it starts to drop in output, you should be fine.

    I have been using cheap fleabay chinese cells, ultrafire cells and top of the range AWs for years and haven't had any trouble. I've discarded cells based on their voltage before charging and their holding voltage after charging. I've even put four unprotected cells in series in an incan and run it until it dimmed. One or two cells felt warm to the touch, and after checking them with a volt meter found they were fine. Li-ions actually perform better when warm, so can take a bit of heat.
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  2. #122
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    Default Re: Ultrafire 18650 3000mA exploded

    Hello Anzycpethian,

    When "rapid venting" takes place, pressure builds up inside the light. The weakest part of the light lets go and the pressure is relieved.

    So far, and this will vary according to the various flashlight designs, the weakest points of lights that have had these rapid venting occurrences have been blowing the head and tail cap off. There are a lot of variables in this and it doesn't happen that often, but IF history predicts future events... this is what you can expect.

    Tom
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    Most batteries don't die - they are tortured to near death, then murdered...

  3. #123

    Default Re: Ultrafire 18650 3000mA exploded

    i have recently started to gain interest in flashlights, so i stumbled upon this thread and it worried me a bit (ok, maybe a little more than a bit. ).
    then i saw that this isn't isolated case, that these things happen. not often, but still...


    this is the flashlight i own:
    http://www.dealextreme.com/p/zoom-fo...x-18650-125390
    got it with included 18650 battery
    http://www.dealextreme.com/p/ultrafi...-26249?item=20
    and a charger that plugs directly into the flashlight.

    after unpacking, i put the battery into the flashlight, and it worked pretty strong (i don't know how much it was charged). after using it for some days, a friend of mine measured its current at 3.4V. after that, i've charged it with this included charger for an hour, but after charging it was at 3.15V .

    then i put it in a friend's charger for two hours, after that it was on 4.16V.

    i have a few questions:

    1.) what is the lowest/highest safe current value in order to avoid overdischarge/overcharge?
    2.) does my charger behaviour sound dangerous?
    3.) under what conditions (besides overcharge/overdischarge) can explosion happen? does it happen only when operating and shortly afterwards, or it can happen if the flashlight hasn't been on for some time?
    4.) how safe it is for a battery to be in a flaslight all the time? would it be better to take it out if i won't use a flashlight for an extended period of time?
    5.) i've red somewhere on this forum that "overdraw" can cause an explosion too. can you please explain me what exactly it is, since i'm pretty much layman when it comes to electronics.
    6.) if you have any advice or anything that will help me relieve of this new acquired phobia (), feel free to write it here.

    thanks in advance.

  4. #124
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    Default Re: Ultrafire 18650 3000mA exploded

    Hello Fcz,

    Welcome to CPF.

    First of all current is measure in amps or fractions of an amp called milliamps.

    Volts are different.

    Full charge on a Li-Ion cell like you have is 4.2 volts plus or minus 0.05 volts.

    Full discharge is around 3 volts under load, or 3.4 volts resting.

    Next, please understand that these cells don't explode... The can "rapidly vent sometimes with flame" but an explosion is more dangerous. I say this a little "tongue in cheek," but there is a difference.

    Rapid venting occurs during over charge, reverse charge, and as a result of using a damaged cell. Also driving a cell beyond its capabilities in either charge or discharge current can heat thing up to a point where the cell will rapidly vent.

    Some lights have a parasitic drain on the battery. It is not a good idea to leave a battery in those lights because it can lead to over discharge. With other lights it is OK. Over discharge drops the voltage to below the 3 or 3.4 volts mentioned above.

    Your phobia is OK. It is important to pay attention to what is going on when you use and charge these cells. The key is making sure that you are aware and that the phobia is not crippling. I would go so far as to say that a healthy respect is not a phobia but good common sense.

    Tom
    Behind every Great man there's always a woman rolling her eyes...

    Most batteries don't die - they are tortured to near death, then murdered...

  5. #125
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    Default Re: Ultrafire 18650 3000mA exploded

    hi fcz,

    these ultrafire batteries are really bad quality, however with a light that only uses one battery at a time you are still relatively safe.
    The big majority of incidents occur when multiple unprotected cells are used in one flashlight at the same time (3 batteries in the case this thread is about), or while cells are in the charger (when abused and damaged before).
    So never charge cells unattendedly or in a place that will catch fire easily.

    your charger's behaviour does sound very strange, even a very cheap charger should not empty a cell under any circumstances.
    happens

  6. #126

    Default Re: Ultrafire 18650 3000mA exploded

    thanks for your replies.

    i still have a few questions.

    Quote Originally Posted by SilverFox View Post
    Some lights have a parasitic drain on the battery. It is not a good idea to leave a battery in those lights because it can lead to over discharge. With other lights it is OK. Over discharge drops the voltage to below the 3 or 3.4 volts mentioned above.
    how long is it safe for battery to stay in flashlight? i understand that there are many factors here, but can you say approximately, is it a few days, few weeks...?

    where would it best to store the battery out of the flashlight?

    so basically, besides attended charging, my only concern should be to keep the voltage between 3.4 and 4.2? if i have any doubts, the voltage measurement should be good enough indicator that everything is ok?

    this may be a dumb one, but can anything go wrong when you measure voltage with multimeter?

    and could you tell me which 18650 brands are most reliable?

  7. #127
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    Default Re: Ultrafire 18650 3000mA exploded

    Quote Originally Posted by fcz View Post
    and could you tell me which 18650 brands are most reliable?
    Panasonic, Sanyo, LG, Samsung, Sony.

  8. #128
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    Default Re: Ultrafire 18650 3000mA exploded

    Quote Originally Posted by fcz View Post

    . . . and could you tell me which 18650 brands are most reliable?
    Most reliable would still be AW brand. He's one of us, and cares about reliability along with safety. Check out Lighthound.com as a great site to order them from.

    As for your other questions above:

    - If you're using a light on a regular bais, it's safe to leave the battery in the light.

    - A cool, dry place is a good idea for storage. I'd recommend getting a hard-shell Pelican case for that. These come in many different sizes from the very small to the incredibly large. A worthwhile investment.

    - Know exactly how to use a multimeter. These types of cells are no joke. They should not even be handled by anyone who isn't completely familiar with them, the proper way to use them, and the proper way to charge them. There is a very good reason why 18650s and similar cells are not sold to the general public in brick & mortar shops that are open to the public.
    "The World is insane. With tiny spots of sanity, here and there... Not the other way around!" - John Cleese.

  9. #129

    Default Re: Ultrafire 18650 3000mA exploded

    What would happen if one of the batteries where put in the wrong way...and then the light turned on?

  10. #130
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    Default Re: Ultrafire 18650 3000mA exploded

    Quote Originally Posted by TooManyGizmos View Post
    ~

    I wish Paul had tested those charged cells with a volt meter to see if they got overcharged ?

    Why do folks put UN-protected cells in a MULTI-cell light ?

    Will they not work with protected cells ? Does it require IMR cells due to current requirements ?

    I don't own any multi-cell lights for this reason !

    I'm not a Gamblin man .



    All > Solarforce L1200 lights should be examined for possible SHORTING HAZARDS
    ~

    I think a better question is why do they sell unprotected batteries at all!? If they are that dangerous no exceptions should even be considered.

  11. #131

    Default Re: Ultrafire 18650 3000mA exploded

    Because with a flashlight that cuts off reliably at 2.8V or so (per cell), a decent charger and proper care/handling (including checking your batteries with a voltmeter before and after charge or discharge), protection PCBs are pretty much redundant and can even introduce additional problems... I've even bought an 18650 that's labeled as protected, but doesn't include any circuitry at all - it's just a wrapper over the unprotected cell. Much more dangerous than knowingly using an unprotected battery.

    That said, redundancy isn't a bad thing... I've only been using protected cells so far.

  12. #132
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    Default Re: Ultrafire 18650 3000mA exploded

    Well...as a budding flashlight enthusiast, I am certainly glad that I stumbled upon Paul's warning story. He convinced me to go with some of the higher quality, protected cells, a higher quality charger (both of which answered questions I had about *fire at Dealextreme and similar sites), and you all convinced me to start with a single cell 18650! Hope Paul recovered from his injury OK!

  13. #133

    Default Re: Ultrafire 18650 3000mA exploded

    Terribly sorry about that!
    Hope Paul recovers better now...

  14. #134

    Default Re: Ultrafire 18650 3000mA exploded

    This kind of hazard is the sole reason I bought a Icharger 106B+ for balance charging my 4 Eden 3400 mAh Li-Ion batteries (original Panasonic).
    The Ultra fires (they fire 2? ) will be used in my one-battery flashlight (P7).

  15. #135

    Default Re: Ultrafire 18650 3000mA exploded

    Quote Originally Posted by unclevit View Post
    I use Ultrafire 18650 3.7v 3000mAh all the times (in case it's rechargeable cr123a 3.0v-3.6v, i will go for GL brand which is very good). After each charge I will check if the voltage is within limit before putting them back into my flashlight, or stock as spares. I don't use different type or brand of bats in the same light (change all bats at the same time, not half of it). Always the same brand/model/voltage class/mAh. And lastly, I used auto cut-off in my charger (which is Ultrafire WF-139). But becareful, UF is a famous brand and always come out with copies, yes by their own chinese people. There are hi-end chinese lights and batteries companies, but you have to pick the right ones. Never had a problem with genuine chinese brands batteries in all of my night patrols
    I recently was a flashlight Li-ion newbie, purchased 6 different sets of "Ultrafire 3000 mAh", started with two sets, they had problems... I bought more from different sellers, returned the others....all sets had different mAh capacities, and several had slightly different shades of red and battery lengths. I did some research and returned all of them I could, bought some Orbtronics, and found that the "Ultrafire 3000mAh" were more in the range of 1400mAh vs my 3400mAh protected Orbtronics run time for comparison. Also, from research, the "famous" company is Surefire, which Chinese Ultrafire/Truefire/Tangisfire/Superfire/Marsfire/Whatever-fire all copy to get people like you and me to think they are the famous standard! I'm glad you had no problems, and check your batteries, but I just wanted to correct some misconceptions about the very over-rated, under quality, Chinese junk batteries being good or a 'standard'! I have also heard reports of false protection on these....hum....I'm staying away.

    What I'd like to know is: with my protected 3400mAh Orbtronic cells (I dont use the crappo batteries in anything but my single cell "1600 lumen" light), I see these exploding as unlikely, but is there a way to reduce the amount of explosion power (does leaving the tail on lightly really do this -and create a nice big bullet).

    I'm also concerned because after enjoying my 3 cell cheapo lying "3800 lumen" 3x Cree XML T6, I bought a 7x, and since the 26650 Trustfires had been tested on HKJ's site I thought they may be Ok...but am I just leaving myself open to a big bomb if I strike it on a rock hiking with Trustfire use? Nobody seems to know Trustfire 26650 chemistry or reliability, does anyone have info?

  16. #136

    Default Re: Ultrafire 18650 3000mA exploded

    If it ok to use unprotected cells in single 18650 lights? Does it matter for single?

  17. #137
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    Default Re: Ultrafire 18650 3000mA exploded

    Quote Originally Posted by ShawnHu View Post
    If it ok to use unprotected cells in single 18650 lights? Does it matter for single?
    If you dont run it too empty and then try to recharge it.possible

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    Default Re: Ultrafire 18650 3000mA exploded

    Quote Originally Posted by ShawnHu View Post
    If it ok to use unprotected cells in single 18650 lights? Does it matter for single?
    First I gotta say Never Ever, because on many of these blowouts, it was a SHORT, that was the problem, not nessisarily a damaged cell item. So here in the "lets not explode forum" no how no way. The protection protects against dead shorts also.

    With that in mind, what lights are people "getting away with" running an unprotected.

    Not boost:
    It depends on the driver, if the battery can be damaged when used. Some lights using a 18650 might still use a "boost" driver, that can drain a battery down below 0.8v way further down than what would damage a li-ion. So it it still a NO for unprotected in Boost driver lights. With Boost type lights you cannot even see that the voltage has gone way to low.

    Not Incandescent:
    No for Incadescent lights, because they can drain a battery down to 0, even without showing much light. so thats out.

    Lights that stop or slow using single li-ion:
    Lights that have a "buck" type driver, or can accept higher voltages like 2x123 usually slow down, lights using the regulator driver usually slow down. both of those when they "fall out of regulation" will only drain to the lowest led voltage it can operate at. These type of lights are the ones people are running unprotected singles in.
    These lights usually will not drain the battery down all the way, except given a whole lot of time on.

    Direct drive lights, with no driver, will take forver to discharge a li-ion low enough to damage the cell.
    Lights that have built in a cut-out to protect the li-ion, can also stop operating before the battery is discharged to far.

    In-Conclusive:
    So there are light types out there, and you can usually test for the type they are, because they will not operate below the spec voltage. These lights will not easily Damage a li-ion cell from too low of a discharge. But again, you still have no shorts protection.

    Side notes:
    While there is a PTC for shorts protection built into the cell item, I (myself) concider that it solutions nothing inside a light case. It reduces the current flow during a short, by resistance, it does not stop completly (go open). This resistance is on the top of the cell, the heat comming off the resitance it still contained. So while it will slow things down drasticly, and could prevent a problem, i wouldnt count on it.
    Last edited by VidPro; 02-24-2013 at 06:16 AM.

  19. #139

    Default Re: Ultrafire 18650 3000mA exploded

    This is damn scary, especially to a newcomer like me. I'm considering my first 18650 light, but a single cell only. After reading this, I wouldn't even consider a multiple high power cell light.

    The "pipe bomb" comment was interesting. You would think the manufacturers of these lights would incorporate a small, thin machined area of the cell cavity wall, or a threshold pressure plug type of system to allow a minimum force-blowout in the event of a catastrophic battery failure and serious pressure increase.
    Would make sense to me to do something like that.

  20. #140
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    Default Re: Ultrafire 18650 3000mA exploded

    Quote Originally Posted by lightcycle1 View Post
    This is damn scary, especially to a newcomer like me. I'm considering my first 18650 light, but a single cell only. After reading this, I wouldn't even consider a multiple high power cell light.
    You gotta remember that the guy in this incident used 3 really crappy unprotected batteries (that said "protected" on them but weren't, which he couldn't tell) and didn't own a meter so never checked on their actual charge status.
    It's likely that the crappy charger that was used overcharged them, that particular model is known to do that.
    I also consider it likely that Paul unknowingly overdischarged them from time to time.

    The light was a very high-powered incandescent one, that would've pushed the limits of most good batteries available then.
    The batteries used were possibly never in balance to begin with - "recycled" dead cells extracted from laptop batteries are known to be sold with that particular "brand" wrapper on them.


    Paul knew none of this and nearly lost his thumb. But you do know - so don't misuse crappy batteries that belong in the junk and don't be afraid.
    Of course, a risk remains. But that goes for living in general.

    Quote Originally Posted by lightcycle1 View Post
    The "pipe bomb" comment was interesting. You would think the manufacturers of these lights would incorporate a small, thin machined area of the cell cavity wall, or a threshold pressure plug type of system to allow a minimum force-blowout in the event of a catastrophic battery failure and serious pressure increase.
    Would make sense to me to do something like that.
    When most buyers don't care/know about the possibilities/issues the manufacturer doesn't improve the product - even if a massive improvement would be easy and cheap. That's the way it has been for decades. It's called capitalism.
    happens

  21. #141

    Default Re: Ultrafire 18650 3000mA exploded

    Quote Originally Posted by Nyctophiliac View Post
    I may also take off any waterproofing gaskets and O-rings as well, I hardly ever go out in the rain at night.
    I only use NiMh batteries nowadays (eneloop only). I won't even use alkaline batteries because one nearly blew the cap off a flashlight by outgassing hydrogen.

    Tip: drill a tiny hole for venting in your flashlight if you use anything other than what I use (unless, of course, water penetration worries you).
    I own 2x Fenix TK40, 4x Fenix LD20, 4x Fenix LD01, 1x Fenix E01, IlluminaTi XP-G R5 (EDC), 2x iTP A3 EOS Stainless

  22. #142
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    Default Re: Ultrafire 18650 3000mA exploded

    NiMH can vent hydrogen when over-discharged as well...Alkaline cells usually leak when they vent as well..

  23. #143
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    Default Re: Ultrafire 18650 3000mA exploded

    I just picked up the following:
    http://dx.com/p/ultrafire-p10-r5-cre...-1-18650-42972
    http://dx.com/p/ultra-fire-all-in-on...atteries-73441

    I remember reading a long time back, on how unstable li-ion batteries can sometimes be, so before I charged these batteries, I decided to do some googling, and I bumped into this thread. I'm really a novice, and I just wanted a decent flashlight and I decided to pick up batteries while I was at it, of course after reading this thread, I got a bit worried.

    How much worried should I be? Should I just buy a different set of chargers/batteries, or for this torchlight, it's ok with minimal risks?

    Thanks.

  24. #144
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    Default Re: Ultrafire 18650 3000mA exploded

    Hello Vsutra,

    Welcome to CPF.

    There are minimal risks when using high quality chargers and cells. Some other brands of cells suffer from cell to cell consistency and you can run into issues with them. Name brand cells have tighter quality standards, but some of them also fail. The same goes for chargers, but low quality chargers seem to under charge which is not a safety concern but a performance issue.

    You can do some searching and find comments and performance graphs for a lot of different brands of cells and chargers. This will give you a feel for what you have.

    Tom
    Behind every Great man there's always a woman rolling her eyes...

    Most batteries don't die - they are tortured to near death, then murdered...

  25. #145
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    Default Re: Ultrafire 18650 3000mA exploded

    Quote Originally Posted by vsutra View Post
    I just picked up the following:
    http://dx.com/p/ultrafire-p10-r5-cre...-1-18650-42972
    http://dx.com/p/ultra-fire-all-in-on...atteries-73441

    I remember reading a long time back, on how unstable li-ion batteries can sometimes be, so before I charged these batteries, I decided to do some googling, and I bumped into this thread. I'm really a novice, and I just wanted a decent flashlight and I decided to pick up batteries while I was at it, of course after reading this thread, I got a bit worried.

    How much worried should I be? Should I just buy a different set of chargers/batteries, or for this torchlight, it's ok with minimal risks?

    Thanks.
    Honestly, Ultrafire cells should be avoided like the Plague. When I started out, I made the mistake of buying the same charger and a set of Ultrafire cells. The charger is basic as Hell. Too basic. You literally have to keep a constant eye on it and remove the cells as soon as they are fully charged. Even then, I found them hot to the touch and had to set them aside for 15 - 20 minutes to cool down. I soon realized that's not how it should be. So I stopped using the charger. As for the cells, I was not charging up Ultrafires. I was using AW brand cells. Had to ... The Ultrafire cells were literally incompatible with the Ultrafire charger! I soon learned that Ultrafire cells have a reputation that varies from won't charge, won't hold a charge once charged, will charge up once but never again, and work decently. Yeah, that's how bad the Q.C. standards are.

    Honestly, these types of cells are no joke. Yes, they are potentially very dangerous. With brands such as AW, the danger level is diminished by quite a large degree. Though never entirely gone. Some things are still worth paying for. These types of cells and the chargers for them are two of those things. It's simply not the place to try to save a buck.
    "The World is insane. With tiny spots of sanity, here and there... Not the other way around!" - John Cleese.

  26. #146
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    Default Re: Ultrafire 18650 3000mA exploded

    I fell asleep ounce a couple of years ago while charging a battery in my UF 139 charger and when I woke up I checked the voltage and it was at a little under 4.2v. I am careful to charge when I am not sleepy now.
    I am come a light into the world, that whosoever believeth on me should not abide in darkness. Jesus Christ - John 12:46

  27. #147

    Default Re: Ultrafire 18650 3000mA exploded

    Quote Originally Posted by lightcycle1 View Post
    This is damn scary, especially to a newcomer like me. I'm considering my first 18650 light, but a single cell only. After reading this, I wouldn't even consider a multiple high power cell light.

    The "pipe bomb" comment was interesting. You would think the manufacturers of these lights would incorporate a small, thin machined area of the cell cavity wall, or a threshold pressure plug type of system to allow a minimum force-blowout in the event of a catastrophic battery failure and serious pressure increase.
    Would make sense to me to do something like that.
    Don't be stupid with Li-Ion's and you should be fine. Use a charger that does not overcharge, and monitor your cells.

    For multicell lights it's a good idea to use protected batteries.

    I have a two cell light that I use 2x NCR18650 unprotected batteries in. They get charged as a pair and I don't let them get low on voltage in case there is a capacity difference. No big deal really.

    I think people make a bigger deal out of the dangers of "explosions". There are a lot of other household items that are more likely to get us than a quality battery charged with a quality charger exploding in a quality light.

  28. #148

    Default Re: Ultrafire 18650 3000mA exploded

    That's two bad. But there's some concerns about this case.

    1. for 18650 (dimension 18cm by 65cm), there's a pressure releasing structure in the cap. once the inner pressure reaches the limitation designed, the structure will work to avoid explosion from over pressured.

    2. in this case, the cap pressure structure seems to be deactivated because the manufacturer might use low-cost 18650 battery shell. so next time be sure to avoid from buying cheap ones unless you know it well.

    3. charging problem. normally the 18650 needs several hours to be fully charged. he charged it over night. so it could be 6-8 hours. if the charger's current is 1000mAh, the means that this 18650 has been OVER charged two time more than it needs. Thus, it's very dangerous. Because most common rechargerable batteries store the energy in chemical energy. If it is over charged, the shell can't control this fierce reaction very well.
    --Referrence TRANSRET

  29. #149
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    Default Re: Ultrafire 18650 3000mA exploded

    Hello MrKnowHow,

    Welcome to CPF.

    Keep in mind that Li-Ion chargers use a Constant Current/Constant Voltage charging algorithm. This means that while it will start out charging at 1000 mAh, that charge rate is reduced as the cells voltage goes up. Charging for 6 - 8 hours does not automatically equate to over charge. Now charging to too high a voltage does mean the cell was over charged and that causes damage to the cell. This is why we monitor new cell voltage at the end of the charge when evaluating a new charger.

    Tom
    Behind every Great man there's always a woman rolling her eyes...

    Most batteries don't die - they are tortured to near death, then murdered...

  30. #150

    Default Re: Ultrafire 18650 3000mA exploded

    I wouldn't touch anything by Ultrafire, especially Li-Ion batteries. Not even for chargers. I am going to be getting a couple Panasonic or Tenergy cells, and a NiteCore i4.

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