Lithium-ion battery safety 101

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SawMaster
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Also you should check with the airline(s) you’re flying on and if they have a “FAQ” page with their details online, then print it out too. The airline folks will find that easier to reference should they have any concerns, and airlines themselves may have additional requirements not spelled out in the FAA or TSA regulations.

While this has been mostly worked out at this point I expect the future to bring more specific details including specifications regarding acceptable boxes and carriers for cells, and maybe even the devices Li batteries are installed in themselves. Right now a baggie meets the specs for being in plastic, yet we all know that the this thin plastic could easily be damaged in a bit of turbulence. We LiIon enthusiasts know better than to rely on a baggie, but the ‘average Joe’ doesn’t, nor do most airline employees. Considering the stakes involved I think it’s a situation which could be handled far better than is currently being done.
_
If we preach and teach Li safety where we can, we can reduce the number of problems occurring which benefits us directly_ Big Smile

Mikeadoo
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SawNaster thanks for the tips. I will do that also. As far as what my battery is in, I still have it in the box it came in with the charger and everything including a little travel pouch that the battery sits in snugly. It’s cardboard box but it holds everything nice and tight. I knew about them phone batteries exploding in the note phones. Almost bought one until I seem that craziness on the news.
My uncle actually works for the airport we are using so I will talk with him about it also to make sure I have all of the correct information needed just in case, to be safe

Mike

Mikeadoo
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gauss163 wrote:
gauss163 wrote:
3.7V * 26.8Ah = 99.2Wh so it is below the 100Wh limit (probably designed with that in mind).

That said, if the pack doesn’t have the Wh stated on the label, then you are at the mercy of how they may (wrongly) calculate it. They might possibly use a number higher than 3.7V for the nominal voltage (e.g. 5V), and then you would be over the limit. Based on what I have read, one cannot expect any intelligence on such matters from TSA employees.


Here’s the link. I’m NOT making any money at all with this link.

https://www.amazon.com/Anker-PowerCore-Portable-Capacity-PowerPort/dp/B0...

Mike

Mikeadoo
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It does say some stuff on the battery. I’ll try and post a picture if possible. How do I do that? It’s asking for a url. I can’t take one with my tablet or just use one from off of my computer and put it on here? Help please

Mike

Mikeadoo
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gauss163 wrote:
gauss163 wrote:
3.7V * 26.8Ah = 99.2Wh so it is below the 100Wh limit (probably designed with that in mind).

That said, if the pack doesn’t have the Wh stated on the label, then you are at the mercy of how they may (wrongly) calculate it. They might possibly use a number higher than 3.7V for the nominal voltage (e.g. 5V), and then you would be over the limit. Based on what I have read, one cannot expect any intelligence on such matters from TSA employees.


heres the battery

that should be a picture from photobucket. dont know if i did it right though Tired

Mike

Mikeadoo
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Not working for me >:(

Mike

teacher
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Mikeadoo wrote:

heres the battery

that should be a picture from photobucket. dont know if i did it right though Tired

At this point… that would be a no. Big Smile

You never know how a horse will pull until you hook him up to a heavy load./"Bear" Bryant 

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Mikeadoo
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nothing i do is working. and when it does work it doesnt…. it shows a picture of a cat saying picture not found lol

Mike

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Excellent resource

"In the land of the blond the one eyed man is king."

*This message is protected with ROT26 encryption.Old Lumens

Yokiamy
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Another interesting link:

Vaping incidents US Navy

Mikeadoo
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gauss163 wrote:
Mikeadoo wrote:
It does say some stuff on the battery. I’ll try and post a picture if possible. How do I do that? It’s asking for a url. I can’t take one with my tablet or just use one from off of my computer and put it on here? Help please

Below is a photo of the label from here They are using 3.6V nominal so 3.6V * 26.8Ah = 96.48Wh which is under the 100Wh limit.

!https://i.stack.imgur.com/0VAzq.jpg!


Sorry guys just got back home yesterday and was beat. I took the battery and didn’t have single problem at all. Thank you all for the help. I appreciate it. Believe it or not we did lose power and were using our phones a ton to take pictures of the fish we caught and they needed charging constantly (tablets and the families phones). Only needed to charge it once, but the 10 light only got down to 4 or 5 for the charge level. Quite heavy but it worked great.
Thanks again everyone.

Mike

m_a_schuster
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Many of us have had issues with battery tube and spring length/stiffness causing compression (axial) damage to Li-ion cells.

I just ran into this with an Astrolux S42 pre-order (posted elsewhere here) in which the effective length of the 18350 battery tube is too short, and screwing it all the way causes the bottom of the cell casing to be flattened slightly.

What is the risk? Throw away all deformed cells, no matter how trivial?

As it turns out, a lot of research has been done on this, much of it published in the Journal of Power Sources.

I ran into the following study which looks at exactly this situation. It is behind a ScienceDirect paywall, but the viewable abstract gives an interesting perspective. There are other articles evaluating compression damage from the sides.

http://www.sciencedirect.com/science/article/pii/S0378775316314641

        Highlights

•Short circuit happens when an 18650 battery cell is axially compressed to 4 mm.
•Deformation is localized in the positive terminal/endcap region.
•Axial compression of jellyroll creates a circumferential crack in the separator in top region.
•Deformation of shell casing and jellyroll can be simulated by FE model and explained analytically.

 

hank
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Yeek.

Quote:
There are four different stages in the force-displacement curve, corresponding with deformation of various components in the endcap assembly. A short circuit happens at a displacement of 4 mm. … Based on the precise analysis of the mechanical behavior, the cause of the short circuit during axial loading was clarified. Two failure mechanisms in the separator at the top section of the cell explain the possible causes of short circuit.

Designing and assembling li-ion cells should be done by someone who can imagine all the things that can possibly go wrong, and try to avoid them.
This sounds like a “house of cards” cell design where one failure leads to another.

Reminds me of

Quote:
If carpenters built houses the way programmers build programs, the first woodpecker that came along would destroy civilization.

— Weinberg’s Second Law of Computer Programming

Corollary:
Woodpeckers are just attempting to remove bugs.

hank
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Quote:
They are not designed to be sold directly to consumers.

No designer could have imagined this sort of leakage from commercial use channels to consumers would occur.

We have similar problems with a lot of things that somehow consumers get their hands on unexpectedly.

Antibiotics, for example; or some of the hardware those militia guys like to run around with.

yasenf
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Bulgarian translation / Превод на български

За кого се отнася:

Тази информация споменава някои рискове за безопасността за потребители, които ползват за пръв път Литиево йонни батерии. Не се опитваме да направим пълен наръчник за използването на Литиево йонните батерии, нито да обясним техническите причини за опасностите от Литиево йонните батерии. Идеята е да бъде базова информация за по-нататъшно четене и разбиране.

Винаги ще има известни спорове по съветите за безопасност. Някои от тези съвети може да не се отнасят, ако сте били асистенти на Dr. Goodenough(link is external), но смятаме че са подходящи за нови потребители. Трябва да си давате сметка за вашите знания и ниво на опит.

+*Литиево йонните батерии могат да се използват безопасно, когато се ползват правилно.
Литиево йонните батерии могат да бъдат опасни, когато се използват неправилно.*+

• Купувайте качествени батерии.
o Спестявайки малко пари като вземате батерии без доказан произход не си заслужава.
o Някои по-евтини батерии може да са фалшиви или да са втора употреба.

 A QA story from a BLF member.

External link
External link

o Потребителите с опит вадят и използват батерии от лаптопи и друга електроника.
 Изчакайте докато съберете достатъчно опит, преди да опитвате.
http://budgetlightforum.com/node/32720

o Ревюта на батерии.
http://budgetlightforum.com/forum/batteries/rechargeable/reviews
http://budgetlightforum.com/forum/batteries/rechargeable
http://www.lygte-info.dk/info/indexBatteriesAndChargers%20UK.html is external)

• Купете си качествено зарядно за батерии.

o Това е още едно нещо, от което не трябва да се пести.
o Не толкова качествена батерия може да бъде безопасна в добро зарядно, но никоя батерия не е безопасна в некачествено зарядно. (SawMaster)
o Четете ревюта. Купувайте марки с добри ревюта.

o Какво да търсите в доброто зарядно:
 Защита от презареждане.
 Защита от обратно поставяне на батерията.
 Независими канали, така че всеки слот да може да зарежда и разрежда различни типове батерии едновременно.
 Вижте каква информация ви дава зарядното – дали е това, което търсите – имас диоди и с LCD дисплеи.

o Зарядното трябва да зарежда до 4.2V +/- 0.05V, но след зареждането, батерията може да има различни показания.
http://budgetlightforum.com/node/45344

o Ревюта на зарядни.
http://budgetlightforum.com/forum/batteries/chargers/reviews
http://budgetlightforum.com/forum/batteries/chargers
http://www.lygte-info.dk/info/indexBatteriesAndChargers%20UK.html

Купете и използвайте мултиметър.
o Много хора харесват дигиталните мулти метри (DMM).
o Научете се да мерите волтажа на Литиево ойонните си батерии.
o http://www.lygte-info.dk/info/Measurement%20UK.html
o Забележка: Не всеки е съгласен, че е необходим мулти метър, но много хора ги препоръчват.

• Зареждане/Разреждане
o Батериите могат да се зареждат при температури: 0*C – 45*C (32*F – 113*F)
o Батериите могат да се разреждат при температури: -20*C – 60*C (-4*F – 140*F)
o http://batteryuniversity.com/learn/article/charging_at_high_and_low_temp

• НЕ презареждайте батериите.
o Максималния волтаж трябва да е 4.2V.
o Ако зареждате само до 4.1V може да ви даде повече цикли на зареждане.
o Доброто зарядно помага да се избегне презареждането
o Зарядните може да зареждат +/- 0.05V и това е в нормата.
http://budgetlightforum.com/node/45344
o След зареждане проверете волтажа на батериите си с мултиметъра (5 минути след зареждането).
o http://batteryuniversity.com/learn/article/charging_lithium_ion_batteries

• НЕ преразреждайте батериите си.
o Много хора започват да зареждат, когато батериите достигнат 3.5- 3.6V
o Батериите са празни, когато достигнат 2.7-3.0v. Презаредете.
o Батериите се повреждат ако достигнат до 2.5 волта.
o Батериите не трябва да се използват ако достигнат до 2.0 волта.
*
• НЕ зареждайте батериите при температура под замръзването. (0*C / 32*F)*

• НЕ оставяйте батериите си да се нагряват прекалено.
o Ако оставяте фенера си в колата през лятото, не-зареждаемите батерии са препоръчителни пред Литиево йонните презареждащи се батерии.
o По-високата температура изхабява (намаля качеството) батерията по-бързо, но до температура под 60*C (140*F) това може да не е опасно.
http://budgetlightforum.com/node/42497
http://batteryuniversity.com/learn/article/charging_at_high_and_low_temp

• За дългосрочно съхранение (месеци) най-добре е да се съхраняват при 40-50% капацитет. (3.77-3.87V)
o http://batteryuniversity.com/learn/article/how_to_store_batteries

• Когато не са във фенер, съхранявайте батериите в кутийки.
o Това предпазва от късо съединение и физически наранявания.
o
o Никога не носете батериите без калъф в джоба или чантата си.
o https://www.youtube.com/watch?v=k1LjSuq0rk8
o https://i.kinja-img.com/gawker-media/image/upload/fmehyjzcfccnkcs03xau.gif

• Не използвайте батерии с физически наранявания.
o
o Батерия с нарушена обвивка може лесно да предизвика късо съединение.
o Tutorial: Rewrapping a battery

• Батериите със защита в общия случай са по-безопасни от батериите без защита.
o Батериите със защита имат платка, която ги защитава от презареждане и преразреждане.
o Защитната платка увеличава дължината и диаметъра на батерията. Защитените батерии не винаги влизат във всеки фенер – моля проверете какви батерии приема фенера.
o Някои фенери имат защита против преразреждане – проверете тази фукнкция на вашия фенер.
o Някои по-мощни фенери могат да задействат защитата на защитените батерии – проверете си фенера и имат нужда от незащитени батерии.

• Фенерите с повече от една батерия имат повече риск от фенерите с една батерия.
o Ако сега започвате, по-добре се ограничете до използването дна фенер с една батерия.

• Когато използвате фенери с повече от една батерия, за да ограничите неравномерното разреждане на батериите (основен риск за безопасността), важно е всички батерии::
o Да са един и същи вид,
o Да са от един и същ производител, и по-добре една партида
o Да имат еднакъв капацитет (Ah) ,
o Да са заредени с еднакъв волтаж.
o Добре е да ги маркирате и използвате заедно през цялото време.

• Зареждайте батериите на места, където няма запалими материали.
o Слагайте зарядното на плот, а не на диван.

НИКОГА не оставяйте зареждащи се батерии без надзор.
o Проверявайте ги периодично да не са горещи. Ако са само топли, няма проблем.
o Забележка: Има различни мнения колко често трябва да се проверяват дали не са горещи.
o http://www.local10.com/news/local-10-investigates/lithium-ion-battery-bu
• Повредените батерии могат да предизвикат пожар!

_„Условия на неправилно използване като презареждане, преразреждане и вътрешно късо съединение могат да доведат до повишаване на температурата на батериите много над препоръчителните от производителя. При критични температури може да се задейства верига от екзотермични реакции. Тези реакции водят до по-нататъшно увеличение на температурата, което води до увеличение на кинетиката на реакцията.Тази катастрофална самоускоряваща се деградация на Литиево йонните батерии се нарича „термално бягство““
“По време на термалното бягство може да се достигне температура от 900 °C, и батерията изпуска сериозно количество горящ и (ако се вдиша в голяма концентрация) отровен газ.”
Royal Society of Chemistry http://pubs.rsc.org/en/content/articlehtml/2013/ra/c3ra45748f

• Ако Литиево йонна батерия се запали ПОТЪРСЕТЕ ЛЕКАР НЕЗАБАВНО.
o Запалените Литиево йонни батерии произвеждат водороден флуорид. Симптомите от нанесените вреди на организма не са видими незабавно.
 батерията изпуска сериозно количество горящ и (ако се вдиша в голяма концентрация) отровен газ Royal Society of Chemistry http://pubs.rsc.org/en/content/articlehtml/2013/ra/c3ra45748f
o Потърсете лекарска помощ веднага. Не чакайте докато се появят симптомите.
o http://www.candlepowerforums.com/vb/showthread.php?141137-Inhaled-vapors

*• Мненията дали е добре да се използва магнит за пъпка се разминават.

• НЕ мокрете батериите.

• НЕ горете батериите.*

• Изхвърляйте батериите на определените места.
o Canada – http://call2recycle.ca/(link is external)
o United Kingdom – http://www.batteryback.org./(link is external)
o United States – http://call2recycle.org/(link is external)

o Дръжте батериите далеч от деца и домашни любимци.
o Когато се погълнат малките батерии спират в гърлото. Слюнката спомага електрическа верига и може да се получи сериозно изгаряне на гърлото до 2 часа..
o Сериозен проблем за деца и домашни любимци.
o Основно е проблем за батерии с пъпка, но потенциален проблем за всички батерии.
o http://www.chop.edu/centers-programs/kohls-injury-prevention-program/lithium-button-batteries#.VuDp4jG-P7M
o http://www.emedicinehealth.com/battery_ingestion/article_em.htm

Още информация за литиево йонни батерии (на английски):
• A Litany for Beginners: http://budgetlightforum.com/comment/904373#comment-904373
• Search post for “safety” – http://budgetlightforum.com/node/26665
• Li-ion Battery Safety and Shopping Guide – http://budgetlightforum.com/node/16699
• Li-ion Safety Concerns – http://batteryuniversity.com/learn/article/lithium_ion_safety_concerns
• Lithium based batteries – http://batteryuniversity.com/learn/article/lithium_based_batteries
• Battery Chemistry – https://batterybro.com/blogs/18650-wholesale-battery-reviews/18880255-ba
• Types of Lithium Ion – http://batteryuniversity.com/learn/article/types_of_lithium_ion

Технологията на производство на Литиево йонните батерии се променя бързо. Моля проверете датата на промяна на първия пост.

Mr.Scott
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Thank you Yasenf!

Jack Kellar
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Cheers, yasenf Thumbs Up

rickw12
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Beginner’s question: If protected cells are generally safer than unprotected, why use unprotected at all?

Rick

m_a_schuster
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rickw12 wrote:
Beginner's question: If protected cells are generally safer than unprotected, why use unprotected at all?

 

I can think of a couple of reasons:

  • Bulk. Protected cells are longer than unprotected cells, due to the circuit board which must be mounted onto the end. Some flashlight designs do not allow for this, and the protected cells will not physically fit.
  • High current drain. The protective circuit is designed, among other things, to prevent the consequences of a short circuit. Newer high-power flashlights can draw many amps of current during normal operation. An unprotected cell is required to deliver this amount of current because a protection circuits cannot distinguish between legitimate high-drain and a dead short.
greginoregon
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I have a question regarding an 18650 battery that seemed to overcharge. I pulled this battery from a lap top pack. I believe its a Sanyo
numbers on it are “ocnm4e9” and under that is “148750”

I use an Xtar VC2 charger.

The cell wasn’t over discharged, according to what the charger said when I put it on to charge. Also, it was still hitting max brightness in the light, an Astrolux S1.

The cell charged to max volts appropriately, but the capacity was at 4,100mah and still going when I took the cell off the charger. It was slightly warm.

I wonder how that Mah reading is possible and is the cell damaged? Is it safe to use?

 

Astrolux S1 NW

Thrunite t30 V2 NW

Surefire Titan AAA

Thrunite T10 V2 NW

Lumen Top Tool AA

Streamlight 2L-X

Astrolux S41 Nitchia

Convoy S2+ NW

De-Power 1AA

Terralux Pro 1

Astrolux k01 Nitchia

Lightbringer
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Capacity is measured when discharging, not charging. Else a Pb-acid battery that trickle-charges forever would have a huge capacity.

I wouldn’t worry too much.

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Funtastic
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greginoregon wrote:
I have a question regarding an 18650 battery that seemed to overcharge. I pulled this battery from a lap top pack. I believe its a Sanyo
numbers on it are “ocnm4e9” and under that is “148750”

I use an Xtar VC2 charger.

The cell wasn’t over discharged, according to what the charger said when I put it on to charge. Also, it was still hitting max brightness in the light, an Astrolux S1.

The cell charged to max volts appropriately, but the capacity was at 4,100mah and still going when I took the cell off the charger. It was slightly warm.

I wonder how that Mah reading is possible and is the cell damaged? Is it safe to use?

I know this is an old post

Sounds like the battery had very high resistance stopping it from reaching full charge

I’d never use a laptop pull in the Astrolux S1

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Paul321
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LG Stay Safe Battery website.

I found LG’s Website www.staysafebattery.com.
It is informative in the way of lithium-ion battery safety, from a CYA sort of perspective.
My take away from watching the videos is “Don’t say we didn’t warn you”, as perhaps a legal defense posture.
There is a link to the LG Lithium -Ion Battery Safety Guide – which is a warning not use their bare cells.

Paul-

hank
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Chuckle. Yep, that’s a keeper. The illustration at 2:21 is …. instructive.

Though I wondered how the arc was maintained — is that CGI or is it real?

In other thoughts: If I install enough of the antigravity floating cells shown in the video, I’ll have my long-promised flying car!

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malkoff junkie
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I have one of those TURNIGY pouch cases and wanted to know is it ok to keep 18650 , NiMh, and Lithiums together in there,
….or should I just get separate cases for each?.
thanks.

Malkoff !

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No problem but don’t just throw the cells in there because they may short.

malkoff junkie
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thanks . is there a way to stop that?.
cheers Agro.

Agro wrote:
No problem but don’t just throw the cells in there because they may short.

Malkoff !

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F.e. keep them in plastic boxes. I guess that’s the best combination of safety and usability. Or use a rubber band to keep them together. Or put them in zip bags.

wle
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why not use protected cells?

cost
protection is usually unnecessary in a flashlight
capacity is lowered, or it may be too long
you want high drain, which isn;t unsafe usually

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