Are Li-Ion Batteries really dangerous?

Yenster

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Are they really dangerous to use in flashlights?

Yeah, I've seen the You-tube videos of people throwing them in fires...or intentionally charging them at 40V and 20 Amps. I know about the laptop battery recalls where some defective PCB circuits shorted, which then pushed 3.5 Amps at 19.5 V through single li-ion cells.

But they are so commonly used almost everywhere these days. They're in cell phones, laptops, cameras, ipods, electric shavers, even bluetooth headsets that's constantly in your ear. And I don't hear about that many issues given their vast use in everyday electronics.

So, what do you think? Do you feel it's safe to use Li-Ion 18650s and RCR123A batteris in your flashlights?
 
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JimmyM

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Lithium ion is a high power density chemistry. So a lot of energy is available if something goes wrong. Of course there will be statistical anomolies where ANY use causes failures. Don't over charge, don't over draw current and statistically, they're quite safe.
I'm going to make the claim that you are more likely to get in a car accident than you are to have a Li-Ion cell go foul (vent with flames).
How many cell phones, iPods, and laptops are in use all over the world? If they were a generally unstable device, no one would use them due to the legal liability.
 

TorchBoy

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I'm going to make the claim that you are more likely to get in a car accident than you are to have a Li-Ion cell go foul (vent with flames).
I'm sure you're right, but I still don't want to use them on my head. :tinfoil:

If they were a generally unstable device, no one would use them due to the legal liability.
I guess cars are so popular because mostly it's the nut behind the wheel af fault if it goes wrong.
 

Yenster

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Has anyone actually experienced a problem with a Li-ion battery while inside an alluminum flashlight? I'm wondering if it could really explode inside a U2 (or clone) and blow up. Maybe the only real risks are during the charge cycle...has anyone experienced a problem there?

If you have experienced a problem, I'm wondering, how bad was it, and are you still using Li-ion batteries in flashlights?
 

DM51

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If you:
  • Buy good quality Li-Ion PROTECTED cells
  • Use a good quality charger
  • Don't charge them at >1C
  • Don't charge them to >4.2V
  • Attend to the charge, watching out for any sign of overheating
  • Don't discharge them at >2C (runtime should be >30 mins)
  • Don't discharge them to <3.5V resting (or <3.0V under load)
  • Make sure they are balanced with other cells when used in multi-cell applications
  • Inspect them regularly for any sign of damage, dents, discoloration etc
  • Recycle them when they can no longer hold ~80% of charge (4.0V)
Then you will not have a problem with them.
 

LuxLuthor

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Has anyone actually experienced a problem with a Li-ion battery while inside an alluminum flashlight? I'm wondering if it could really explode inside a U2 (or clone) and blow up. Maybe the only real risks are during the charge cycle...has anyone experienced a problem there?

If you have experienced a problem, I'm wondering, how bad was it, and are you still using Li-ion batteries in flashlights?

There are some reports by people in these forums with Li-Ions "exploding" (SilverFox likes to call it "rapid venting") while inside of lights. Some of this is due to poor QA by 'certain' manufacturers, it may be due also to an internal short developing in a cell that was over discharged prior to recharging, or a break in the battery can's insulation shorting against the inside of the light. Certainly you increase your risk when you use them in series, without balancing, and certainly if you use unprotected cells.

At least Jimmy's frequency caution is an improvement over another esteemed member who claimed you were more likely to be struck by lightning. You can search for the threads where people have posted their 'incidents,' but the main problem is the steady influx of new users who have not taken the time to learn about how to take care of Li-Ions, and think they are the same as any other portable consumer battery. I was in this category for well over a year of being a member here.

Despite Jimmy's statement about their being used in all those devices...there have been many catastrophic events triggering tens of millions of Li-Ions being recalled. I don't agree with him in general on his reassurance because in large part, they become more dangerous in our DIRECT DRIVE flashlights. Flashaholics have long used unprotected cells and charge with no balancing of voltages. That separates us from RC users, and commercial Li-Ion packs that have circuit protection PCB's and/or cell balancing in their packs.

Very few flashaholics will follow all of DM51's most excellent list of guidelines.

.
 
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VidPro

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If you:
  • Buy good quality Li-Ion PROTECTED cells
  • Use a good quality charger
  • Don't charge them at >1C
  • Don't charge them to >4.2V
  • Attend to the charge, watching out for any sign of overheating
  • Don't discharge them at >2C (runtime should be >30 mins)
  • Don't discharge them to <3.5V resting (or <3.0V under load)
  • Make sure they are balanced with other cells when used in multi-cell applications
  • Inspect them regularly for any sign of damage, dents, discoloration etc
  • Recycle them when they can no longer hold ~80% of charge (4.0V)
Then you will not have a problem with them.

thats just common sence :D like saying a consumers computer should have a firewall and anti-virus . well common li-ion sence. which reminds me of all the home computers that have viruses all over them :sick2:

i think that due to its great power capability some people take it WAY beoynd that, and are at much greater "risk" and even then they get away with it a lot.

Respect the power, know the specs.
 

Yenster

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If you:
  • Buy good quality Li-Ion PROTECTED cells
  • Use a good quality charger
  • Don't charge them at >1C
  • Don't charge them to >4.2V
  • Attend to the charge, watching out for any sign of overheating
  • Don't discharge them at >2C (runtime should be >30 mins)
  • Don't discharge them to <3.5V resting (or <3.0V under load)
  • Make sure they are balanced with other cells when used in multi-cell applications
  • Inspect them regularly for any sign of damage, dents, discoloration etc
  • Recycle them when they can no longer hold ~80% of charge (4.0V)
Then you will not have a problem with them.

Hmmm....it just hit me. Reading through this list by DM51, which initially seemed too much for the general public, I realized that these precautions are already inherently implemented for other products BUT NOT flashlight batteries. For example...cell phone battery...it's protected, comes with a good dedicated charger, won't charge >1 C by design, won't overcharge in the phone, won't discharge by > 2C nor over discharge due to the design of the phone. So simply, the battery can only be used in that phone and the overall design has already ensured it's use will be low risk and there are no variables.

This can be said for just about every other Li-ion commonly available, laptops, cameras, ipods, etc....

Except with the flashlight Li-ion battery, there are a lot of variables. I can buy an unprotected 18650, put it into various different chargers, use it in various different flashlights that people like to mod...pushing the brightness envelope, and so the risks are NOT AUTOMATICALLY ensured by design like in the cell phones or cameras.

So I guess this is not much of a debated topic...with the correct precautions, these are as safe as cell phones, laptops, and Ipods.
 
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mchlwise

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Hmmm....it just hit me. Reading through this list by DM51, which initially seemed too much for the general public, I realized that these precautions are already inherently implemented for other products BUT NOT flashlight batteries. For example...cell phone battery...it's protected, comes with a good dedicated charger, won't charge >1 C by design, won't overcharge in the phone, won't discharge by > 2C nor over discharge due to the design of the phone. So simply, the battery can only be used in that phone and the overall design has already ensured it's use will be low risk and there are no variables.

This can be said for just about every other Li-ion commonly available, laptops, cameras, ipods, etc....

Except with the flashlight Li-ion battery, there are a lot of variables. I can buy an unprotected 18650, put it into various different chargers, use it in various different flashlights that people like to mod...pushing the brightness envelope, and so the risks are NOT AUTOMATICALLY ensured by design like in the cell phones or cameras.

So I guess this is not much of a debated topic...with the correct precautions, these are as safe as cell phones, laptops, and Ipods.

Excellent insight. :grin2:

So basically they CAN be dangerous with flashlight use because of the lack of built-in protections that other devices have, but with some care they should be just fine.

:popcorn:
 

JimmyM

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Despite Jimmy's statement about their being used in all those devices...there have been many catastrophic events triggering tens of millions of Li-Ions being recalled. I don't agree with him in general on his reassurance because in large part, they become more dangerous in our DIRECT DRIVE flashlights. Flashaholics have long used unprotected cells and charge with no balancing of voltages. That separates us from RC users, and commercial Li-Ion packs that have circuit protection PCB's and/or cell balancing in their packs.

Very few flashaholics will follow all of DM51's most excellent list of guidelines.

.
I had a whole reply written in response as a clarification to Lux's disagreement with my opinion (repectful, of course). Then I had connectivity issues. My opinion was based on proper use and care. Barring that, things can very well get messy. Statistically speaking, I still think that, given the proper respect, Li-Ions are not the boogey-man devices of horror stories. But with any powerful device things can go wrong. I just don't want to overstate the statistical probability of things actually going wrong.
2 questions.
1) How many Lithium Ion cells are in use in devices in the US alone?
2) How many reported catastrophic failures have actually ocurred?
I understand our usage is outside the rigid constraints of production electronics. But proper use and care will cover that. See what I mean?
 

JimmyM

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If you:
  • Buy good quality Li-Ion PROTECTED cells
  • Use a good quality charger
  • Don't charge them at >1C
  • Don't charge them to >4.2V
  • Attend to the charge, watching out for any sign of overheating
  • Don't discharge them at >2C (runtime should be >30 mins)
  • Don't discharge them to <3.5V resting (or <3.0V under load)
  • Make sure they are balanced with other cells when used in multi-cell applications
  • Inspect them regularly for any sign of damage, dents, discoloration etc
  • Recycle them when they can no longer hold ~80% of charge (4.0V)
Then you will not have a problem with them.
Lets see. Per my practices
  • Buy good quality Li-Ion PROTECTED cells - Yes for 18650s, Yes for Cs, No for Ds
  • Use a good quality charger - Yes, Bantam BC-8
  • Don't charge them at >1C - Yes, 500mA 18650s, 500mA for Cs, 1A Ds
  • Don't charge them to >4.2V - Limited by charger
  • Attend to the charge, watching out for any sign of overheating - Intermittent checking
  • Don't discharge them at >2C (runtime should be >30 mins) - ROP-Lo on 18650s, ROP-Hi on Cs, 64275 on Ds.
  • Don't discharge them to <3.5V resting (or <3.0V under load). Check. Protected 18650s and Cs, and hotdriver for Ds
  • Make sure they are balanced with other cells when used in multi-cell applications. Check. Balance charging.
  • Inspect them regularly for any sign of damage, dents, discoloration etc. Check. Everytime they're charged. Also test individual voltages.
  • Recycle them when they can no longer hold ~80% of charge (4.0V). Haven't use them long enough.
 

jimjones3630

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David thanks for excellant list. Hope don't think are picking on you. My dog in this are A123 and Emolis.

If you:
  • Buy good quality Li-Ion PROTECTED cells Unless they are safer chemistry A123 or Emolis. Use protected until understand why.
  • Use a good quality charger
  • Don't charge them at >1C Unless A123 and Emoli then 4C and 3C respectively
  • Don't charge them to >4.2V
  • Attend to the charge, watching out for any sign of overheating
  • Don't discharge them at >2C (runtime should be >30 mins) not >70A or >20A respectively
  • Don't discharge them to <3.5V resting (or <3.0V under load)Unless A123 then discharge to <2v
  • Make sure they are balanced with other cells when used in multi-cell applications
  • Inspect them regularly for any sign of damage, dents, discoloration etc
  • Recycle them when they can no longer hold ~80% of charge (4.0V)
Then you will not have a problem with them.

These cells have a different potenial for harm. They don't vent flames rapidly, no risk to overdischarge with A123. Are they really dangerous? What they can do is dump 70A in what seems a micro sec. A123 cells are positive ground. Have melted off rings of tailcap spring. The light got so hot to hold in so short a time I had an adrenaline dump while trying to unscrew the tailcap.

These cells and the technology that is following is going to reshape current wisdom on what is possible. One year ago no one talked about or showed mods with these cells. People were long awaiting protected Li io C cells. A 4D mag outputting 200w wasn't conceivable.
 
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LuxLuthor

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I had a whole reply written in response as a clarification to Lux's disagreement with my opinion (repectful, of course). Then I had connectivity issues. My opinion was based on proper use and care. Barring that, things can very well get messy. Statistically speaking, I still think that, given the proper respect, Li-Ions are not the boogey-man devices of horror stories. But with any powerful device things can go wrong. I just don't want to overstate the statistical probability of things actually going wrong.
2 questions.
1) How many Lithium Ion cells are in use in devices in the US alone?
2) How many reported catastrophic failures have actually ocurred?
I understand our usage is outside the rigid constraints of production electronics. But proper use and care will cover that. See what I mean?

When I talk about this, Jimmy, (much respect to you also :bow:) I have to include all those who use them without learning the proper care, nor following guidelines like DM51 posted. Compound that with people using them in series, in direct drive flashlights--changes the safety relative to commercial & balanced PCB packs with chargers built for their specific pack/application.

Seeing threads like this one, and yet another series of recent posts in another thread in the General section here....and thinking back on the number of posts where people did have flashlights that 'exploded,' there are still a number who are not aware of what can go wrong if you are not careful and educated on the Lithium Cobalt cells.

That is specifically what I am addressing--not the commercially made, PCB regulated packs--but even with those, there have been enough disasters to require tens of millions of battery pack recalls...at very significant expenses to companies like Sony. :)

If you look at the number of new users, and the number who don't own a quality Li-Ion (balance) charger with proper mA & termination voltage, there not being any universal cradles for them, the many who use cheaper and/or unprotected cells, and poor QA manufactured cells, hearing about people soldering these into packs, seeing this recently posted thread with YouTube video of the guy giving false reassurance, but not clearly identifying the chemistry of those cells, etc....that all combines in elevating my concerns. I still think there are many flashaholic Li-Ion users who do not understand many of these points.

I agree with you however, that when one learns about them, and they are given the proper respect, there is very little danger. I am certainly not saying they are randomly and spontaneously exploding for no reason. Anyway, no sense preaching to the choir, since you and I already know all of this....it's the others not reading these threads which is the concern. :ohgeez:
 

JimmyM

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When I talk about this, Jimmy, (much respect to you also :bow:) I have to include all those who use them without learning the proper care, nor following guidelines like DM51 posted. Compound that with people using them in series, in direct drive flashlights--changes the safety relative to commercial & balanced PCB packs with chargers built for their specific pack/application.

We're good, Lux. No sweat brudda.
 

JimmyM

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· Buy good quality Li-Ion PROTECTED cells
· Use a good quality charger
· Don't charge them at >1C
· Don't charge them to >4.2V
· Attend to the charge, watching out for any sign of overheating
· Don't discharge them at >2C (runtime should be >30 mins)
· Don't discharge them to <3.5V resting (or <3.0V under load)
· Make sure they are balanced with other cells when used in multi-cell applications
· Inspect them regularly for any sign of damage, dents, discoloration etc
· Recycle them when they can no longer hold ~80% of charge (4.0V)
Then you will not have a problem with them.
Lets see. Per my practices
· Buy good quality Li-Ion PROTECTED cells - Yes for 18650s, Yes for Cs, No for Ds
· Use a good quality charger - Yes, Bantam BC-8
· Don't charge them at >1C - Yes, 500mA 18650s, 1A for Cs, 1A for Ds
· Don't charge them to >4.2V - Limited by charger
· Attend to the charge, watching out for any sign of overheating - Intermittent checking
· Don't discharge them at >2C (runtime should be >30 mins) - ROP-Lo on 18650s, ROP-Hi on Cs, 64275 on Ds.
· Don't discharge them to <3.5V resting (or <3.0V under load). Check. Protected 18650s and Cs, and hotdriver for Ds
· Make sure they are balanced with other cells when used in multi-cell applications. Check. Balance charging.
· Inspect them regularly for any sign of damage, dents, discoloration etc. Check. Everytime they're charged. Also test individual voltages.
· Recycle them when they can no longer hold ~80% of charge (4.0V). Haven't use them long enough.
 

DM51

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David thanks for excellant list. Hope don't think are picking on you.
Not in the least. I think this is a good discussion, and when I put up that list I thought it likely there would be ways to improve it, and that people would point these out. You have quite rightly pointed out the differences that apply to A123 and Emoli technology.


I certainly did not mean this list to say "These are the rules and everyone must obey them!"

I think nevertheless it is a reasonably good checklist for those who are new to Li-Ion technology. Those with more experience, who are used to the capabilities of their cells and lights, and familiar with the voltages/amperages involved, may safely decide to push things a little further because they understand what is involved.

For example, it's not recommended to run a WA1185 with 3x18500s, because 3.3A is >2C, but Li-Ions can take >2C quite happily for short bursts, so it is OK as long as you realise that and don't do it continuously. Hotwire gurus like you, LuxLuthor, JimmyM and others, all understand this stuff.

Li-Ions have many advantages, but they are actually not that great for high-current applications. NiMH, A123 and Emoli are all better for that. And as Yenster has pointed out, millions of Li-Ions are in use worldwide in everyday appliances, but all of these uses are at fairly low power. Cellphones that have 4 hrs talk-time per charge are operating at only 0.25C (most have much more than that). Most laptop computers are the same – you don't see any laptops with a run-time less than 2 hrs (0.5C). The built-in chargers are conservative and purpose-designed. If these things do ever fall down, it is usually when they skimp on cell quality, which is probably the biggest single cause of problems. I think poor manufacturing specs and inadequate QC was what caught Sony out with those packs they supplied to Dell. Lol, if Sony had got its cells from AW, they wouldn't had had this huge and expensive problem.

The trouble is, there are some tempting prices for cheap crappy cells from unscrupulous dealers, and many CPFers are falling for these deals. Those cells in inexperienced hands, and the correspondingly crappy chargers that are sold with them, are what worry me.
 

jimjones3630

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Jimmy is a guru no doubt, myself I am a immitator. I would be glad to have the ability to copy as well as Jimmy makes.
 

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