Odd 123 event...?

[Mr Bigglow]

This mystifies me but no doubt there's a logical explanation. I have an old incan SL Scorpion that I kept in the hall closet. A few months ago I discovered that the Eveready CR123s inside, which are probably old enough to be past their shelf life, would no longer power the incan light, but that they would run an LED unit, so I put them aside for that until last week, when I finally loaded one in my spare E2D, intending to use it for non-critical purposes. I then found that the 123 would only run the E2D on low power, with the three flashes on initial turn on signaling that the battery was almost dead. However, using the E2D for about 5 minutes on a fix-it job, it seemed to be way too warm when I picked it up again, so I quickly removed the battery and something, it seemed like battery fumes, made me cough at that point, convincing me I'd had a narrow escape from a melt-down. BUT, I later decided that the light probably got warm for another reason and, mysteriously, the E2D now works perfectly in both high and low modes using the same battery- I'd never know the 123 wasn't a new one and this is a flashlight I'm familiar with. My questions: what could have happened, why is the battery now working perfectly, and am I risking destruction of the E2D if I keep using it?

 

[Connor]

Not sure what happened here but I advise you to remove the battery from your flashlight immediately and discard it. Do NOT use it again.

 

[pjandyho]

Here's my question to you. Is the two batteries really worth the life of your E2DL and yourself?

When you start smelling a foul smell it is because the battery probably suffered a short and vented it. I am no expert regarding batteries but my mind tells me to discard the batteries and insert a new set. Wouldn't you?

 

[kramer5150]

Old cell, possibly an internal short or polarity reversal.

Discard and replace

 

[DM51]

Before I move this to the Smoke & Fire section, or your light blows up, whichever occurs first, I would urge you to do as the others advise, and discard the old cells. If you have compounded the problem by using one of the old cells with a new one to run your E2D, trouble is imminent.

 

[Mr Bigglow]

A harsh tone discerned there in the last. I started out too early today, or hit my head getting up or something- so a typo occurred and got repeated- I was using a (one-cell) E2B not an E2D. And, I was hoping to be told that something other than self-discharge had made the batteries look weak at the outset, but OK... discarding a battery that would have cost me $5 back in the day doesn't come easy to a cheapskate like me, but I will do it.

I'm sure we're all on the same page in thinking that using one weak lithium cell at a time is generally a safe practice?

 

[Connor]

I'm sure we're all on the same page in thinking that using one weak lithium cell at a time is generally a safe practice?

Generally it is, but a cell that got very hot without a cause and produced noticeable levels of "fumes" should be considered dangerous. Usually this doesn't happen, so consider yourself unlucky. ;-) Or perhaps very lucky, 'cos from the sound of it this particular cell wasn't too far away from catching fire/exploding.

 

[Mr Bigglow]

Generally it is, but a cell that got very hot without a cause and produced noticeable levels of "fumes" should be considered dangerous. Usually this doesn't happen, so consider yourself unlucky. ;-) Or perhaps very lucky, 'cos from the sound of it this particular cell wasn't too far away from catching fire/exploding.

Yeah the other thing is that it's not certain the light got hot because of the battery and not because it was touching a heat source- once out of the tight space I couldn't be sure. The fumes were sort of definite- so why then does the battery work so well now? But it will be junked.

Hopefully tomorrow will be a better typing day.

 

[DM51]

My apologies if my post came across as harsh - that was not my intention at all. I was concerned for your safety, more than anything else. I'm relieved to hear it wasn't an E2D.

 

[kramer5150]

I'm sure we're all on the same page in thinking that using one weak lithium cell at a time is generally a safe practice?

Generally yes it is safer than two cells. Those cells that vent/flame are dangerous in any scenario and should be discarded.

 

[DaveTheDude]

Yeah the other thing is that it's not certain the light got hot because of the battery and not because it was touching a heat source- once out of the tight space I couldn't be sure. The fumes were sort of definite- so why then does the battery work so well now?

Others have done the right thing by focusing on the safety aspects of your incident first. But now let's return the focus of this thread to your question, highlighted above. The likely reason your primary cells appeared to be nearly dead, but have now miraculously returned to life, may be due to passivation effects.

[FONT=arial,helvetica,sans-serif]Lithium batteries are affected by a chemical interaction known as passivation. Passivation is a term that describes a thin film of lithium chloride that forms on the surface of the lithium anode. The film operates to protect the lithium from self-discharge when the load is removed from the cell. This film is essentially a high resistance layer between the electrodes, and is one of the neat tricks of chemistry responsible for the long storage life of lithium cells. [/FONT]​

Here's the kicker...Passivation may cause voltage delay after a load is placed on the cell.​

http://www.spectrumbatteries.com/si...lderpictures/.pond/DischgCht.jpg.w180h117.jpg

[hotlinked image replaced by link - DM51]​

After a load is placed on a cell, the higher resistance of the passivation layer causes the cell's voltage to drop. Placing a load on the cell slowly removes the passivation layer, reducing the internal resistance. This causes the cell's voltage to return to a near-peak value, and the voltage usually remains more or less steady, assuming a constant load on the cell. ​

Once the load is removed, the passivation layer will start to reform, and voltage delay may again be a factor when subsequent loads are applied. ​

There are a bunch of different factors that interact to affect the degree of passivation a stored cell may experience, including the energy density of the cell; the cell's particular chemistry; the amount of time the cell has been stored (longer storage = more passivation on the anode); storage temperature (higer temps = higher passivation); and the cell's [FONT=arial,helvetica,sans-serif]discharge temperature, among others (colder environments generally show passivation effects more than warm environments).[/FONT]​

This pretty much exhausts my understanding of lithium battery chemistry, so any follow up questions are better directed to the community as a whole. There are lots of folks in this forum who understand this stuff on a professional level, and they may be able to direct you to good sources for self-education. I strongly encourage you to read up on this, if for no other reason than to help ensure your family's safety (on the theory that some family members may not immediately recognize danger when a "simple" flashlight seems to be getting a bit hot). lovecpf​

 

[bkumanski]

An I am FAR from being a chemistry or battery expert, but I may weigh in here. If the light became "unusually" hot and this is when the cell had the odor, it sounds like you shorted the battery on the light body itself somehow. Now this could be the battery (missing insulation) or a short in the light itself. Either way, kinda sounds like the battery was overloaded for a short while and vented, as the others have said.

 

[Monocrom]

Single-cell lights such as an E1B generally are less prone to vent with flame than a multi-cell light. A lot less. But it can still happen. Good way of increasing the risk is using a CR123 cell that is very old.

Just not worth it.

Nowadays you can get quality CR123 cells for under $1.50 each.

 

[SilverFox]

Hello Mr Bigglow,

DavetheDude hit the nail on the head with his explanation.

Your cell got hot while it was burning off the passivisation layer off. Once that layer is removed, the cell behaves almost like new, but it will have lost some capacity, and it will run a little hotter than a new cell.

Hot cells often have odors associated with them, so that is normal as well.

I don't see any issues if you continue to use the cell in a single cell light, but don't expect it to last as long as a new cell. Also, if you store it for awhile, the passivisation layer will return faster than it did before and it will be harder to burn it off. Eventually the cell won't be able to hold voltage high enough to run the light.

With lesser quality cells, this happens in a few months to a year. With quality cells the process is greatly slowed down, but it still happens. The best way to keep the cell close to "fresh" after extended storage is to briefly run it in a light every month. This will burn the passivisation layer off as it forms and minimize the voltage drop in the cell when you first turn it on.

When testing cells in this condition on the ZTS tester you will have to do a minimum of 5 tests before you burn through the layer and start to get results that are meaningful. Even then if the layer is thick the results will be off.

In testing at 1C rates I have observed cell temperatures in the 120 - 140 F range as the discharge starts, then the cell will stabilize at around 110 F. It is better to use cells like this in the winter when the extra heat helps to warm your hands.

Tom

 

[pjandyho]

Question: does passivisation occur before or after the cell has been used? Or does it occur regardless of whether the cell has been used or not? Surefire claims that lithium CR123 batteries have a 10 years shelf life. Does this mean that during this 10 years there won't be any passivisation? I am intending to buy a few boxes of lithium CR123s despite the fact that I am using Li-ion more frequently now. Does lithium CR123s store well in room temperatures? The average temp here is about 30C (About 86F).

 

[SilverFox]

Hello Pjandyho,

At the end of 10 years, quality CR123 cells will have only degraded to about 85% of their original capacity due to passivisation and natural self discharge.

Manufacturers put additives into the electrolyte to try to control this degradation. Some mixes are better than others, and the quality cells usually use the best mixes.

When you use the cell, you burn the layer off. One of the manufacturers, I can't find the paper right now but a search should turn it up, did a paper on this and outlined a way to minimize these degradation effects during storage. If I remember correctly, the cells were subjected to a small current periodically. The down side to this is that the cells capacity is eventually used up.

Cell chemistry reactions slow down with cooler temperatures and visa versa. Your cells would store better if you can sore at cooler temperatures. I don't know the exact change, but would suppose that at 20 C they may only last for somewhere around 6 - 7 years.

Tom

 

[pjandyho]

Thank you very much Tom. That is most helpful. I guess I could just go ahead and get those cells. Doubt it would take me more than 2 years to use them up anyway. Your explanation is tremendously marvelous. Just love CPF University!

 

[Mr Bigglow]

Others have done the right thing by focusing on the safety aspects of your incident first. But now let's return the focus of this thread to your question, highlighted above. The likely reason your primary cells appeared to be nearly dead, but have now miraculously returned to life, may be due to passivation effects.

[FONT=arial,helvetica,sans-serif]Lithium batteries are affected by a chemical interaction known as passivation. Passivation is a term that describes a thin film of lithium chloride that forms on the surface of the lithium anode. The film operates to protect the lithium from self-discharge when the load is removed from the cell. This film is essentially a high resistance layer between the electrodes, and is one of the neat tricks of chemistry responsible for the long storage life of lithium cells. [/FONT]​

Here's the kicker...Passivation may cause voltage delay after a load is placed on the cell.​

http://www.spectrumbatteries.com/si...lderpictures/.pond/DischgCht.jpg.w180h117.jpg​

[hotlinked image replaced by link - DM51]​

After a load is placed on a cell, the higher resistance of the passivation layer causes the cell's voltage to drop. Placing a load on the cell slowly removes the passivation layer, reducing the internal resistance. This causes the cell's voltage to return to a near-peak value, and the voltage usually remains more or less steady, assuming a constant load on the cell. ​

Once the load is removed, the passivation layer will start to reform, and voltage delay may again be a factor when subsequent loads are applied. ​

There are a bunch of different factors that interact to affect the degree of passivation a stored cell may experience, including the energy density of the cell; the cell's particular chemistry; the amount of time the cell has been stored (longer storage = more passivation on the anode); storage temperature (higer temps = higher passivation); and the cell's [FONT=arial,helvetica,sans-serif]discharge temperature, among others (colder environments generally show passivation effects more than warm environments).[/FONT]​

This pretty much exhausts my understanding of lithium battery chemistry, so any follow up questions are better directed to the community as a whole. There are lots of folks in this forum who understand this stuff on a professional level, and they may be able to direct you to good sources for self-education. I strongly encourage you to read up on this, if for no other reason than to help ensure your family's safety (on the theory that some family members may not immediately recognize danger when a "simple" flashlight seems to be getting a bit hot). lovecpf​

Hello Mr Bigglow,

DavetheDude hit the nail on the head with his explanation.

Your cell got hot while it was burning off the passivisation layer off. Once that layer is removed, the cell behaves almost like new, but it will have lost some capacity, and it will run a little hotter than a new cell.

Hot cells often have odors associated with them, so that is normal as well.

I don't see any issues if you continue to use the cell in a single cell light, but don't expect it to last as long as a new cell. Also, if you store it for awhile, the passivisation layer will return faster than it did before and it will be harder to burn it off. Eventually the cell won't be able to hold voltage high enough to run the light.

With lesser quality cells, this happens in a few months to a year. With quality cells the process is greatly slowed down, but it still happens. The best way to keep the cell close to "fresh" after extended storage is to briefly run it in a light every month. This will burn the passivisation layer off as it forms and minimize the voltage drop in the cell when you first turn it on.

When testing cells in this condition on the ZTS tester you will have to do a minimum of 5 tests before you burn through the layer and start to get results that are meaningful. Even then if the layer is thick the results will be off.

In testing at 1C rates I have observed cell temperatures in the 120 - 140 F range as the discharge starts, then the cell will stabilize at around 110 F. It is better to use cells like this in the winter when the extra heat helps to warm your hands.

Tom

Ah, what a great set of answers- fits everything that I observed and matches the conclusion (a suddenly fully working cell). I am now confident my batteries were passivised by their probably 15 years on the shelf. I'll get the cell under discussion and its mate out of the discard bin and use them up, one at a time in the E1B (yup, I got it wrong the second time too)- and cautiously. Thinking that far back, I have worked out that they probably cost me more like $7.50 each so they owe me some lumens, darn it.

Thanks guys! lovecpf too!

 

[bkumanski]

Wow, guess MY understanding of lithiums has a lot of catching up to do! Guess I was thinking in simple electrical short terms. Thanks all for the info!

 

[zipplet]

This happened to me with some very old cells I got from ebay when I first got into high power flashlights. I bought the cells in 2006 and they were 9 years old at the time. They suffered from some voltage depression and got very warm if I used them in a high current device initially.