Exploding Lithium Flashlight Batteries?

See: http://www.equipped.org/blog/?p=42

If you want to comment on this Equipped.org Blog entry, please do so in this thread

One of my favorite flashlighlights is the Underwater Kinetics UK 4AA eLED, 18 hours on a set of alkaline batteries. I called the company and spoke to an engineer about whether or not the light could be used with lithium batteries, because the specs call for Alkaline batteries. The light is fully regulated, so lithium batteries will work and should give even longer runtime with a longer shelf-life. However, per the company, use of lithium batteries nullifies all of those hazardous area ratings. The light has a pressure vent in its tailcap in case I do decide to disregard the manufacturer's recommendation. It would probably work and I've considered trying lithium batteries, but if the issue is sporadic, it may test fine and then fail when you really need it.

As for the debrief at Doug's link, quality control rules. The lithium batteries I have on hand are Energizer AA and AAA and Surefire 123's.

The second "explosion" was probably the good cell set off by heat from the first cell to fail. The CR123 cells have a flammable electrolyte. With two cells, one is close to the limit allowed for transportation on passenger aircraft by UN and DOT regulations (although it is allowed since they are in an apparatus). There is a lot of energy there that can cause a problem when something goes wrong.

Chinese Li-MnO2 (CR123) and Li-FeS2 (similar to Eveready L91) are generally not as safe as Japanese or American made cells. (The Chinese cells are improving, so don't think they won't be as good in a few years.) They use different electrolytes and lack some features. It should be noted that most "American" made CR123 cells are made in Japan, or in a Japanese designed plant, and wrapped with the US manufacturer's label. The Japanese Li cells and Eveready L91 and L92 cells are a fine product that can be trusted. However, Eveready alkaline cells have a tendance to leak due to a poor crimp seal design. Duracell has a better seal design. I have had less experience with RayOVac alkaline cells, but all experience to date has been favorable.

Button cells have much less energy, so failure is not as dramatic. Because the cell case cannot take much pressure without deforming, poor electrolytes or internal problems are readily observable. Considering all the button cells in watches, with very few problems, one can be confident in button cells. Again, most are made in Japan, often packaged with a US manufactuer's name. Japan really knows how to make a quality product.

Finally, I agree that one should not look to save money on batteries by buying cheap, unless it is cheaper because of buying in bulk. There is a lot of energy in cells that can cause problems if released as heat rather than electrical work. One carries the weight of batteries because they are needed, so spend a little more and buy quality.

Spud

This whole episode sounded pretty scary to me. Its one thing, if you are carrying a flashlight around and it catches on fire, but when it catches on fire in a confined space, like a cockpit of an airplane, you got a whole new set of problems.

I think it’s only a matter of time before one of these cases ends up before a judge in a court. Such a case could be extremely damaging since when lawyers sue, they sue everyone involved and not involved: manufacturer, wholesaler, retailer, Internet provider and website host where a flashlight was purchased.

As the author rightfully concluded, for your own and other's safety: "DO NOT USE CHINESE MADE CYLINDRICAL LITHIUM BATTERIES."

Way back in the mid '70s when lithium batteries first came along, Larry Penberthy (founder of MSR) sold a single D cell to replace the 4 D cells in a Justrite headlight. At the time, we all used the Justrite for mountain rescue because it had 10-24 hours of usable light, depending on the bulb.
It was specified that we had to have an air vent in the battery case because of the venting gas from the lithium cell. The battery case Penberthy sold was a plastic cigarette case with a cheap battery clamp to hold 2 cells, one was a shunt dummy to allow the single cell continuity. The batteries were very expensive for the day and only came as 3v D size.
Batteries have come a very long was since then and nowadays you do not see much about potential hazards mentioned, personally, I thought the original problems had been solved to the point venting was not so much an issue. I always wonder how my waterproof Inova with two CR123 batteries is holding up with the sealed case. So far, so good.
I once put a set of Energizer Titanium batteries in a Mini-Mag and while using it it got so hot I could not hold it in my hand, had to drop it and took it outside, turned off to let it cool. Later I checked on it, it was still very hot and after opening the light, one battery had expanded and leaked causing some sort of chemical reaction which caused the heating. The batteries were brand new and it would seem, did not like the sealed mini-mag case! I have not bought any more titanium batteries since and went back to standard alkalines.
Battery fires and explosions are not something most people expect, but certainly need to be aware of! Cheers!

It was interesting to see that burnt up battery. Having used Lithium batteries for a number of years almost exclusively for my outdoors and survival gear having zero problems.
I recently switched back to Alkaline because my new GPSMAP 60CSx does not like Lithium batteries, it actually shuts itself down. It is a shame because Lithium batteries offer a number of benefits in a survival situation, longer life and shelf life and less weight. I hope to find a solution to this issue soon, Garmin claims their software update has fixed it but practical experience has proven otherwise.

A follow up note regarding Energizer Alkaline cells. If you use the cells within a year or two, and the temperatures are moderate, you will have little problem with the Energizer Alkaline cells. For long term use, or storage for emergencies, I have found approximately 40% to leak. Thus for longer term uses, I now rely on Duracells.

One must always remember that there is a lot of energy in a battery cell. Use what you need, but realize the risk. Don't use a high rate cell such as a CR123 unless you need the high rate capability. I want a flashlight to last many hours, more than 10h on a set of batteries, so a lower rate (and therefore safer) cell works great. Thus I tend to use a lot of alkaline cells, rechargeable NiMHx, and Li button cells.

Spud

> my new GPSMAP 60CSx does not like Lithium batteries, it actually shuts itself down.

Eeek! I have one of those (without the S). I just went and tested it and it has the same issue. I tried putting the NiMh back in and changing the battery type in the set-up screen to Li-Ion (sic - it certainly won't run on Li-ion rechargeables and apparently this option is the one which is supposed to work with Lithium) and it still didn't work.

Interestingly, my older GPSMap 60 does work with Lithium. I suspect I tested it when I got and and tried it again just now. I hadn't retested the newer device until I saw your post. I had been carrying a pair of Lithiums as my emergency backup for the GPS unit, thinking they would work.

Thanks for the warning. I've just sent ETS a $10 donation via their JustGive link, because this may have saved me some severe embarrassment.

Garmin assures me that they are working on the problem. I did try a set of Lithium batteries that were run down to under 1.5v each, and they did work perfectly.

Something the article doesn't say: if your Lithium or Li-ion battery does vent with flame, avoid breathing the fumes or getting any of the ejecta on your skin. It can have some nasty stuff in it. If you do get it on you you need to take it very seriously. You may think you are OK at first, but after a few hours the compounds break down into things which poison you, by which time they will have migrated all over your body. There are cases in the Candlepower forums; nobody died, but they were off work for a few days and, eg, unable to drive themselves to the hospital. As I recall, the symptoms included an all-over body rash and the liver going into over-drive to try to metabolise the poison.

I did have a Lithium Ion rechargable battery explode on me. I had a new, 3rd party battery pack for my Yaesu VX-7R amateur radio handie talkie in the factory smart charger for about 5 hrs when it exploded. It threw hot material on a stack of papers, starting a fire in my living room. If one of the roommates hadn't heard it pop, it could have burnt my house down.

While it was a 3rd party battery, it was from a reputable supplier of replacement batteries that has been around for a long time.

So that gas is the source of the destinctive smell of lithium batteries. I figured it had to be something out gassing or something, so I've always opened my G-2s ever week or so to let them air out.

I'm glad I've always used Energizer, Duracell or Surefire 123s.

Thanks for the heads up on the Duracell/Energizer seal quality. I'm about to replace every battery in the house.

How long have you kept Rayovacs? I've had a number of failures recently in batteries with a 2011-2012 date on them. They are AAs about six years old or newer. It seems to be worse in MiniMAGs than other lights. Recently installed & little use & they've swollen to the point it's not worth the trouble to get them out.

Sometimes it is the charger. I have had a number of chargers for radio batteries stop working right and over charging batteries to the point of explosion. Not with a lithium battery, but with both NiCad and NiMh batteries.

The topic is primary NON-RECHARGEABLE batteries. Rechargeable batteries are a whole different ball game. I generally do not recommend them for survival gear in any case, but that's an entirely different subject.

UTAlumnus,
I have only stored RayOVac's for two years to date. No problems yet. Since my wife joined Costco, we have purchased Duracell's at a good price. I would note that Kirkland brand AA's appear externally to be Duracell. I have also stored those cells for almost two years without problem.

Spud

I've had a lot of leakage from Rayovac alkaline AA's in the past year. I use them almost exclusively now so it's a little hard to compare, but I definately feel like I've had a higher failure rate than a few years ago when I mostly used Duracells. Maybe I'll go back.

Like Doug, I had personally never heard of any stories of lithium primary cells exploding or catching fire in flashlights. Seems like a very rare event. Anyway, without any hard evidence to the contrary, like staying away from Chinese-made lithiums, I guess I agree with the suggestions except for modifying one thing.

I think talking a bit more about "plastic" flashlights would be helpful, along the lines of what I think RAS was getting at in his post. Not all "plastic" flashlights are alike. I mean, after warning us away from Chinese-made lights, an additional effort is made to mention that some Chinese-made flashlights may be OK. Something similar to that statement for plastic-bodied flashlights might be helpful, too.

First, there's the distinction between cheap, flimsy plastic flashlights like what you might find at the supermarket vs. high quality plastic-bodied flashlights. Like RAS, I'm a big fan of the UK 4AA eLED light, and also the Streamlight ProPolymer series. The cases of these lights are very strong. However, secondly, even with high quality flashlights, if someone is very concerned about this very rare possibility of exploding flashlights, then they might want to further subdivide plastic lights by whether they have additional safety features.

For example, dive rated lights are generally extremely strong and great for survival situations, however, they are also generally sealed up tight. That could lead to a catastrophic build up of pressure. In constrast, industrial/work lights, like the UK eLED or ProPolymers, often have safety features like pressure relief vents. (They also often have hydrogen catalysts but lithiums can generate gasses other than hydrogen. And even if only hydrogen was generated during a short circuit, I'm not sure that the catalyst could cope with a very rapid venting of hydrogen from a battery. I think the catalyst is meant to handle gradual build ups of hydrogen from alkalines.) These features could help prevent an explosive flashlight case failure.

One comment about the pilot's story. Since plastic is a thermal insulator, I wonder if his flashlight was already heating up when he first noticed that the flashlight had gone out? I suspect that it was, but it didn't feel alarmingly hot to him before he put the light away in his flight bag. Just a guess, but if he had an aluminum light, he might've felt it getting too hot and might have handled the situation differently. I suppose that's one distinct advantage of an aluminum flashlight. But then again, a pressure relief valve might have simply resulted in a ruined flashlight with crispy batteries instead of a projectile/explosive hazard.

Check the date on the side of the batteries. The date on one or both of the last ones to fail were 2011. IIRC they were putting about a 10 year date on them about 2001 or 2002 (2011 exp. date). I should have remembered the old saying about if its too good to be true...

These could have been up to six years old but were probably newer. They used to have a 10 year date on them. I think the current date is only six. I'll have to check a couple of other sources.

Dive lights always have a catalyst pellet in them. This helps reduce the danger if the vented gas is hydrogen.

Hello Arney,

I also go by SilverFox on CandlePowerForums. I am heavily involved in battery testing. We have had several reports of the CR123A Lithium primary cells "rapidly venting with flame." In an effort to understand why, we set out developing a test plan and conducting a series of tests. NewBie (on CPF) did the actual testing and we were able to come up with a recipe to cause this "venting with flame" to occur.

The formula we discovered goes like this:

You need an incandescent lamp that draws about 1 C (or around 1.2 - 1.5 amps).
You need one cell at 100% capacity, and the other at around 70 - 80% capacity.
You need an ambient temperature of around 80 F.
You need an enclosure of some type. (More on this later).
You need to run the light completely down, then you need to leave the circuit connected.

Rapid venting with flame occurs 5 - 20 minutes after the lamp goes out. By the way, the temperatures exceed 1000 F for the short time the cell is venting.

This works almost every time with the inexpensive CR123A cells. It never works with the premium cells such as SureFire, Streamlight, Energizer, Duracell, and Sanyo. We haven't tested all of the brands, but we are seeing a trend here.

The problem is that the stronger cell tries to charge the weaker cell. With some temperature, the reaction is able to continue and after "cooking" for a few minutes... bang.

Cells in an open environment will not cook off. You need an enclosure to maintain the heat within the cells. We started out with a flashlight body, then progressed to simply wrapping the cells in some aluminum foil to simulate the flashlight body. This worked quite well.

It would be my "guess" that the pilot, upon discovering that his light had gone out, had pressed the switch several times and may have lost track if it was turned on or not. I believe he ended up with the light in the on position and that allowed one cell to reverse charge the other.

We have discovered that the non-premium cells often are not stable. I have been unable to determine why, but think it has something to do with the quality of raw materials, and perhaps, something to do with the sealing method of the cells. I have cells that tested (on a ZTS tester from www.ztsinc.com ) at 100% initially in April 2006, that are now testing 10% as of November 2006. While I have only observed this with 4 different brands of cells (Radio Shack is not one of them) I don't believe it to be unique. It is quite possible to end up with cells of different states of charge when you purchase them. If all of the other conditions are met, you can end up with cells that "rapidly vent with flames."

This does not seem to be the case with LED lights. We have not been able to get an LED light to vent or flame under the same conditions. I believe the LED just breaks the circuit when the voltage drops below a certain point.

To protect yourself against this, I recommend using premium cells in multi cell applications. If you want to try the "cheaper" cells, it is a good idea to load test them (ZTS tester or simulate a load with a resister and measure the voltage under load and compare it to a premium cell under the same conditions), then REMOVE them from the light when the light dims or goes out. If the circuit is broken, the reaction stops.

To summarize, we need non premium cells, a load that is high enough to heat up the chemistry within the cells, ambient temperatures high enough to sustain the chemical reaction, and a connection that is not disconnected, and of course 5 - 20 minutes for the reaction to complete.

To protect against this, when the light goes dim, remove the cells from the light, and use premium cells in multi cell applications.

Here is NewBie's test thread on CPF.

Tom

Was that with any LED light or regulated/semi-regulated? Many LED lights use a regulation circuit which probably does turn off the light at some point, but will the naked LED bulb do the same?

That question asked, the only non-regulated lights I have 2D & 3D MagLights in which I changed the bulb to an Epieon LED.

Like any diode, the LED itself has a "forward voltage" rating below which current through it drops off rapidly. So theoretically an unregulated "dumb" LED light would be less likely to cause this failure than an incandescent one.

Silverfox:
Are the BatteryStation 123's safe or not? They are among the cheapest batteries that I have seen (with the CPF discount), but they are only about $0.25 cheaper than Surefire batteries, which you categorize as "premium".

Has anybody measured the current and temperature of the premium cells as they are discharged? Perhaps they have a thermostat that disconnects the battery as it overheats.

Excellent! Great to have input from some of the CPF experts on the topic, like you and Newbie. Let me just say that I am always impressed by the professionalism and care that go into the reviews, write-up's, and tests on CPF. This ETS post is no exception. I hadn't visited CPF in a long, long time but after this topic came up on ETS, I started visiting CPF more regularly since I'm a flashaholic-in-denial. But darn it, my flashlight collection has already multiplied in the short time that I've been on CPF again. *sigh* But I digress.

The 100% vs 80% differential between the two cells isn't much, plus your observation of how variable the capacity of unused non-premium primary cells can be in a short time is quite alarming to me. So, even grabbing two brand new or unused CR123a cells from the same non-premium batch is not necessarily safe. Yes, surprising and worrisome indeed.

Anyway, thank you, Silverfox, for your input to ETS. Any reservations I might have had about these guidelines due to lack of data are now resolved.

Hello Ras,

There has been no venting, regardless of how hard we try, with LED lights.

All of the venting has been in conjunction with incandescent lights.

Tom

Hello Harrkev,

Is any battery "safe?" <img src="/images/graemlins/smile.gif" alt="" />

Kevin at BatteryStation is testing all of his cells before they ship. He is only shipping cells that test 100% on the ZTS tester. I believe (and know first hand on a limited basis) that the odds for getting good cells from BatteryStation is extremely good.

Keep in mind that there have been problems with all the brands of batteries. They are extremely rare with the premium brands, but they do occur. The ZTS tester came into being because photographers were having problems with their batteries and wanted a way to insure that their equipment would work when they wanted it to.

The ZTS tester is not perfect. As a matter of fact, it seem to lack precision. However, it does a good job of matching cells to keep you out of trouble.

Tom

Hello Arney,

NewBie tested a bunch of cells that were new and mismatched. I provided him with cells that tested on the ZTS tester from 0% to 80%, and he tested several samples of each. In each test, he coupled a lower tested cell with one that tested at 100%. There were no cases of venting during these tests. To get them to vent, he had to discharge the cell roughly 25 - 30% and couple it with one that was at 100%

I am not sure why this is so. We are still working on this.

I do suggest that in incandescent lights that drain the batteries in about an hour, that you start with cells that test at 100%. There is no reason to add any additional risk to your flashlight use.

Tom