Battery warnings :)

[rolygate]

Guys,

You might know that there has been yet another incident of a 'safe' mod exploding in someone's face (a GLV) and therefore I've had to take the next step in trying to stop these events: publishing a lot more warnings about unprotected Li-ion batteries. All we need to do is make sure that buyers know they shouldn't use them. There won't be any rules or anything like that.

Until it is impossible for a new vaper to buy a mod seen on ECF without knowing they need to use protected Li-ion batts or Li-MN / LiFePO4's, this thing won't go away, and these fires and explosions will still keep happening.

So: I've put up various warnings plus a battery info page. It was a lot of work to research and write that page but it had to be done, and nobody else was going to do it. I'm an engineer and at one time was a sparks, so I know the issues, but small rechargeables are not my game so there could be mistakes. I'd appreciate an email if you see anything that needs fixing. Thanks.

http://www.e-cigarette-forum.com/fo...9007-warning-rechargeable-batteries-mods.html

http://www.e-cigarette-forum.com/forum/ecf-library/129569-rechargeable-batteries.html

 

[duby]

Great info Roly. You made a typo and a few omissions I thought would be worth adding.

Here's the typo

17670 battery - 3.6 v
17mm x 67mm (about the size of two CR-123a batteries, but less overall voltage, 8.4v max vs 6v max from two primary batteries)

Should be 4.2V max vs 6.6v max to be accurate.

In addition he omitted the following

26500 Battery This is "C" cell size.
26650 batter Same diameter slightly longer.

14250, 14500, 17355, 18650, 26500, and 26650 are all available in LiFePO4 chemistry at 3.3V.

Also BDL manufactures LiMn IMR batteries as well as a few others. (Only noted for completeness since AW was regularly listed as a supplier.)

Perhaps you should also make a note about pairing batteries if they are to be stacked. Unpaired/poorly balance batteries in series can also lead to these situations.

Lastly, I'll link a previous post of mine which refers to video footage of a Li-ion battery explosion.
http://www.e-cigarette-forum.com/forum/battery-mods/125347-li-poly-battery-fire-footage.html

 

[BuzzKill]

One other thing Roly , a DEAD short is the worst case for a battery I.E. 0.0 ohms , protected devices limit this issue by limiting the MAX current allowed to flow so they are inherently safer in that aspect.

Over current devices help in this area by limiting the current to the output , there are several devices that are readily available and would be very easy to implement in 90% of the mods out there. And they a very cheap.

Anyhow good info !! operators of a Big Battery Mod need to know this stuff and the MFG's of non protected mod's need to inform the user of this as well.

We will update our site and manual.

 

[WillyB]

I always assumed CR-123A always refered to Primary (non-rechargeable) batts and that the rechargeables were always RCR-123A.

 

[rolygate]

@WillyB
You are right, I need to change the page info to show RCR123 as the rechargeable code, CR123 as the format/size.

 

[rolygate]

@Duby
Thanks, that is all good info, I will put it in.

 

[rolygate]

@BuzzKill
OK. I think there is maybe a difference in US and UK English for this, a short-circuit = a dead short so I will change that if it's not clear.

It would sure be nice to see over-current protection in mods that are using Li-Mn etc. I don't know if it's possible to put that in tube mods though? Many of the tube mod builders don't seem to want to add electronics, maybe it's difficult in the tube format, I don't know. But if you have batteries that can put out 20 amps+ then it might just be a good idea...*

* Just found a spec sheet with a 26650 LiFePO4 that puts out 70 amps 10 sec duty. Wheeeee...

It's good to see vendors implementing safety features and adding battery information to their packaging. To be honest it's something I never understood, how someone can sell a product that will easily explode in the buyer's face if they use the wrong batteries, and they don't even warn them. Surely they can see the risk - not to mention that such a buyer would get a lot of money in compensation if they lost an eye. Beats me.

Anyway things are improving now, everyone is getting better information.

 

[rolygate]

Thanks to all you guys who helped me on this. Also I nicked some stuff from Drozd I think.......

 

[Drozd]

hey Roly...
first I wanted to say something about duby mentioning the BDL IMR batteries...unfortunately the BDL batteries arent known to be the best about QC... secondly their IMRs have a lower C rating than the AWs which almost pushes them back into the realm of Li-Ion as far as drain rates..

as far as LiFePo4 cells go it should also be worth noting that not all of those are created the same either... the Tenergy ones have a max drain rate of < .55A ....where the AW ones have a max drain of 5A ..that's a huge difference

some things that I would find critical are knowing how battery protection works...this thread: The anatomy of a Protected Battery - CandlePowerForums coupled with this bit from battery university does a really good job at illustrating how battery protection works

The battery manufacturers achieve this high reliability by adding three layers of protection. They are: [1] limiting the amount of active material to achieve a workable equilibrium of energy density and safety; [2] inclusion of various safety mechanisms within the cell; and [3] the addition of an electronic protection circuit in the battery pack.

These protection devices work in the following ways: The PTC device built into the cell acts as a protection to inhibit high current surges; the circuit interrupt device (CID) opens the electrical path if an excessively high charge voltage raises the internal cell pressure to 10 Bar (150 psi); and the safety vent allows a controlled release of gas in the event of a rapid increase in cell pressure. In addition to the mechanical safeguards, the electronic protection circuit external to the cells opens a solid-state switch if the charge voltage of any cell reaches 4.30V. A fuse cuts the current flow if the skin temperature of the cell approaches 90°C (194°F). To prevent the battery from over-discharging, the control circuit cuts off the current path at about 2.50V/cell. In some applications, the higher inherent safety of the spinel system permits the exclusion of the electric circuit. In such a case, the battery relies wholly on the protection devices that are built into the cell.

We need to keep in mind that these safety precautions are only effective if the mode of operation comes from the outside, such as with an electrical short or a faulty charger. Under normal circumstances, a lithium-ion battery will simply power down when a short circuit occurs. If, however, a defect is inherent to the electrochemical cell, such as in contamination caused by microscopic metal particles, this anomaly will go undetected. Nor can the safety circuit stop the disintegration once the cell is in thermal runaway mode. Nothing can stop it once triggered.

What every battery user should know

A major concern arises if static electricity or a faulty charger has destroyed the battery's protection circuit. Such damage can permanently fuse the solid-state switches in an ON position without the user knowing. A battery with a faulty protection circuit may function normally but does not provide protection against abuse.

so the LiMN cells don't have a PCB but the better ones still have the other physical protections as well as the safer chemistry...in addition to the fact that their higher max drain rate doesn't put them into an over stressed state...
I find it also important to know that a faulty charger CAN damage the PCB in a protected cell without the user being any the wiser and that this can go unknown til there is a problem...

and just because I think this is important to know:

Lithium-ion cells with cobalt cathodes should never rise above 130°C (265°F). At 150°C (302°F) the cell becomes thermally unstable, a condition that can lead to a thermal runaway in which flaming gases are vented. Manganese (spinel) is the newer of the two chemistries and offers superior thermal stability. It can sustain temperatures of up to 250°C (482°F) before becoming unstable.

mainly because it gives you the temperature benchmarks that things start to go wrong at with Li-Ion:
90°C (194°F) -A fuse cuts the current flow as part of the cell's protection
150°C (302°F) the cell becomes thermally unstable, thermal runaway is imminent and there's no stopping it....

also wanted to say that the user switched...did an excellent job of compiling a lot of the battery info (which I was far too lazy to do in a manner that was easily understandable for everyone) as far as what you're doing goes... I believe it is linked through the ikenvape site as well...

 

[rolygate]

Just wanted to add this note because it seems there are a lot of people who still don't get it: you can't sell a known dangerous product and get away with it if the buyer is injured. If they sue, you WILL have to pay and it won't be cheap. Here is something I just added to one of the posts about these battery issues:

_______________________

And please note the following points very carefully, which may help you understand our stance; this is the legal advice we have received:
a. It is not possible to disclaim responsibility if the products are previously well-known to be dangerous (as here) and no warnings were given (as is still the case with some vendors).
b. A legal action in the case of injury sustained by a buyer of known dangerous products, if supplied with no warnings, would almost certainly succeed. The damages (financial compensation) might be substantial.
c. ECF might also be implicated in an action against a Supplier selling dangerous goods that are clearly known to be dangerous and that have no warnings attached, and where ECF also failed to warn buyers.
_______________________

I've read all sorts of criticism of our stance from the uninformed. Sorry but the above are the facts. We have to protect the buyers, and protect ourselves from vendors who seem to have a death wish. The US is a very litigious society and it's frankly amazing that so far none of the people injured have sued. I think this is because vapers are dedicated to the 'movement', but sooner or later someone will get hurt who doesn't feel the same way. Not sure what the payout for losing an eye would be but it can't be cheap - plus costs of course.

 

[rolygate]

@Drozd
Thanks for this.

OK it seems that AW are the best. I don't normally like to promote one product but in this case it looks like the best advice would be to tell people that AW are a good bet. The whole idea of the info is to give a straightforward answer, so I guess here it should be done. I did see that BDL were not so highly recommended, so they are not stressed as a good alternative.

I'll put in a note about Tenergy vs AW LifePO4 because that is useful to know. It is beginning to look as if there is only one good battery maker though, not sure if that is the case. But I guess if they are the clear winner then we should say so.

I take your point that battery protection is good, but that it can fail and the user is no wiser. Also I am well aware that there are 'good' and 'bad' levels of protection, cheap protected batts are maybe no better than good unprotected ones in the end. Only safe-chemistry batts are actually safe, in the end. So I need to alter the battery info page to reflect that.

It looks as if the best option is an AW Li-Mn. An AW LiFePO4 is a good bet but the voltage is usually lower. Even protected Li-ions aren't necessarily safe. This needs to be added to the page.

 

[rolygate]

Made a bunch more edits to the battery info page. Thanks to all who contributed.

The emphasis is now clearly changed to reflect a preference toward AW Li-Mn's.

As long as there no actual technical errors, it's looking good now.

 

[Drozd]

@Drozd
Thanks for this.

OK it seems that AW are the best. I don't normally like to promote one product but in this case it looks like the best advice would be to tell people that AW are a good bet. The whole idea of the info is to give a straightforward answer, so I guess here it should be done. I did see that BDL were not so highly recommended, so they are not stressed as a good alternative.

I'll put in a note about Tenergy vs AW LifePO4 because that is useful to know. It is beginning to look as if there is only one good battery maker though, not sure if that is the case. But I guess if they are the clear winner then we should say so.

I take your point that battery protection is good - but it can fail and the user is no wiser. Also I am well aware that there are 'good' and 'bad' levels of protection, cheap protected batts are maybe no better than good unprotected ones in the end. Only safe-chemistry batts are actually safe, in the end. So I need to alter the battery info page to reflect that.

It looks as if the best option is an AW Li-Mn. An AW LiFePO4 is a good bet but the voltage is usually lower. Even protected Li-ions aren't necessarily safe. This needs to be added to the page.

it's not so much that there is only one good battery maker...just that the others are extremely hard to find and use a completely different and foreign size code.... just do a search for wolf's eyes or pila batteries.....

that and when it comes down to larger size cells like the 18650 even the *fire brands are just fine...but when we get into 14500 and 16340 (cr123a) and smaller sizes... the only ones that are going to maintain a max drain that is higher than the worst amp draw that we're going to throw at them is the IMR and the LiFePo4...

the thing with the BDL batteries even given thier lackluster reputation for QC is that lets take the 14500 size for example...technically they serve just fine....but they have a C rating of 5C where the AW ones are 8C... what that boils down to is with a 1.5Ω atty at 3.7V we're throwing a 2.47A draw at a battery that can at max put out 3A versus 4.8A ....I'm of the mindset that less stress to the battery is a far safer thing...
and their IMR 10440s are pointless...given the low mAh and barely improved 3C rating... they're just not capable of delivering for our application...

and given that people are going to stack batteries no matter what some people say...I think this is where the danger comes in....if we're stacking batteries that are already running at all out capacity and being overstressed stacking them is just going to compound that problem...
as an example... a 750 mAh 3.7V AW 16340 li-ion cell has a max drain of 1.5A....... and a 510 atty at 3.7V has an amp draw of 1.61A (so we're already overstressed)
stack em for 7.4V and we're looking at further trouble...the max drain doesn't change...we can hope that both cells are discharging equally and that we can split the amp draw between them but the amp draw of a joye 510 atty at 7.4V is 3.22...
so we're overstressing stacked batteries that could just possibly have a PCB that we don't know is good or not and relying on just the physical protections on the cells in a situation where temperature can climb quickly because they are being overstressed...

 

[rolygate]

OK.

And now buGG told me that there are question marks over most of the smaller LiFePO4's because they can't handle the drain, plus people are putting them in Li-ion chargers, which as they are 3.3 volt nominal and 3.6 v max charge is basically cooking them. Someone had their LiFePO4-driven mod blow up apparently.

Well it's simple then. I'll just put that you can only use an AW IMR 26650 charged on a $50 Pila charger. And of course the mod will need some sort of electronics for a dead short trip-out as those monster batts can pump out 70 amps or something.

Sorted.

 

[Dillinger]

I have perhaps a dumb question about protected batts.

When a battery vents, specifically my *fire 14500's, do they vent at the - end of the battery? I've noticed that when some eventually die, there are little slots there and it smells kind of funny. Does this mean my batts could have blown up if not for the PCB?

Any clear description of what exactly the PCB does would be appreciated.

 

[rolygate]

All those I've seen have the gas vents at the positive end, by the button tip. This is why it's suggested that an extra-safe mod would have the batts inserted 'upside down' as that way the gas would easily vent out the bottom end.

Sounds like the PCBs died on your batts then, if you've got burn holes in the casing at the bottom of the cell.

Those little circuit boards are the built-in protection. As they're stuck on the bottom end of the cell, protected batts are longer than than the unprotected ones.

There is a difference between the best and the most basic ones. In theory they trip out if the batt is over-voltaged in the charger; if the batt over-currents on discharge (like in a dead short / short-circuit); and the better ones trip on over-temperature. You have to disconnect the batt to get them to re-set.

The PCBs can get burnt out by a bad charger or due to a static discharge, and it's reported they can fail to a closed state, ie they don't work but the circuit through them is good. This is an unusual fail mode for electronics but I suppose it might happen with a minor melt-down or something. Static zaps can have 20,000 volts so maybe it's possible.

 

[Dillinger]

Thanks for the info. All I know is, when the batts stopped working, I noticed the burn holes in the casing at the - end. So maybe there is some mechanism which causes the batt not to work after the PCB dies? If so, I guess that's good. Although, I have no idea what I'm talking about.

 

[Drozd]

Thanks for the info. All I know is, when the batts stopped working, I noticed the burn holes in the casing at the - end. So maybe there is some mechanism which causes the batt not to work after the PCB dies? If so, I guess that's good. Although, I have no idea what I'm talking about.

see the link I posted earlier in this thread to the CPF thread and the info about the battery protection levels and it should sorta be clear..(the cpf thread comes with pictures)

basically you have a PTC (the vents in the button top and a type of fuse)
the CID (circuit interrupt) ....it's the metal strip and wire that you can make out running down the side of the cell
and the PCB... on the bottom of the cell

the PCB protects against over discharge...like a short or trying to draw too many amps (we've seen this trip in certain devices when batteries are stacked with 510 atties), it also is what cuts the battery off when it reaches too low of a voltage....
and they can be reset in many cases...

the other 2 physically break if the pressure or temperature in the cell gets too high... and there's no resetting of those....both seperate the connection between the cathode and anode of the battery to stop the flow of electricity

 

[Drozd]

OK.

And now buGG told me that there are question marks over most of the smaller LiFePO4's because they can't handle the drain, plus people are putting them in Li-ion chargers, which as they are 3.3 volt nominal and 3.6 v max charge is basically cooking them. Someone had their LiFePO4-driven mod blow up apparently.

Well it's simple then. I'll just put that you can only use an AW IMR 26650 charged on a $50 Pila charger. And of course the mod will need some sort of electronics for a dead short trip-out as those monster batts can pump out 70 amps or something.

Sorted.

lol sarcasm...I get that...
yeah you're going to have people that use the wrong charger....no matter how many times we warn them, I know I always make mention that you need a different charger and link to the suggested one that the AW guy suggests....much like the saying about leading a horse to water....you can point out the appropriate and safe thing to do...but you cant guarantee they're going to listen...though it still amazes me that people will throw handfuls of money to get the newest mod when it comes out...yet cheap out and get substandard batteries and chargers for it...

I believe I remember a liFePo incident....and if I remember correctly there was something odd about that incident... I can't remember 100% though so I don't want to go on record....but it was either tenergy batteries, or a different lithium polymer (like LiPo versus LiFePo4 or something) there was some anomaly to it either way...
I can only speak toward the AW 16340 size ones...which the manufacturer/supplier has come out and said that they are good to a 10C drain rate...on this thread here: NEW R123 with safe chemistry - CPFMarketPlace
where he also includes a discharge graph up to 5C....and did a water torture test with them runing a light from one under water for 30 minutes... I'm reasonably confident that there are safe for our application therefore

 

[rolygate]

@Drozd
OK the page is getting a bit long now, we have a problem that you have to tell people what they need to know, but eventually that info is just too much. So some stuff has to be edited out. You suggest:

...Some things that I would find critical are knowing how battery protection works...this thread: The anatomy of a Protected Battery - CandlePowerForums coupled with this bit from battery university does a really good job at illustrating how battery protection works...

...which I agree with, but it will probably have to be left off the info page as it's getting too big. We need a second page now for additional info, by the looks of it.

Several people have emailed me with advice & info. There are some minor disagreements in that info. I think one problem may be that not everyone is going to agree on some things, like exactly what batteries are a good idea or not.

I think it would be an excellent idea to make up a chart of battery makes vs battery types vs battery sizes -- like those big spreadsheet/charts Candre makes. It could have a green area / amber area / red area for the batteries, if they are advised or not.

In the meantime I will try to make up some sort of a list of which ones from what manufacturer are 'generally recognized as safe', from the lists sent to me. There will be a problem with this, in that not all modders will agree on which batteries to advise or not - and then the commercial suppliers may also disagree in some cases. For example, it doesn't look as if anyone is going to say that the smallest size of battery such as the 10440 is a good idea, even with an AW Li-Mn or whatever - but there are commercial mods out there running that model.

But as we have set out down this road we must keep going. We have to try and give good advice while upsetting the minimum number of people.

...And that is probably one function of ECF anyway - to present many different viewpoints and try to come to some sort of an agreement.