General Li-ion safety

LEDBE
Beyond the basics for Li-ion safety?

I've been doing a lot of reading on lithium rechargeables and must admit, I'm terrified. I ordered some cheap batteries (trustfire protected) and charger (WF-139) and would like to ask a couple questions that have been on my mind. I really would like to get more expensive chargers and batteries, but I'm not "that" into lights yet that I'd like to take that 4x 5x price increase, and even then theres no guarantees.

To make sure I understand this, the main threat is the battery releasing poison gas, the gas building up in the tube, and one end of the light blowing off with extreme force, like a roman candle and likely catching fire. Are there any additional safety measures you could take to protect from this (aside from treating your batteries well), like making a hole in the flashlight body/clicky, or not screwing on your tailcap too tight?

The stories I've read that resulted in an explosion usually have a "non tragic" ending. No one got seriously hurt, at most suffered some light wounds but no fingers lost, no blindness, no house burning down, no death. That leads me to believe that even in a worse case scenario you are given adequate warning either from hissing or heat, to chuck that flashlight and yell grenade. Has anyone heard any tragic stories caused by lithiums in flashlight? What are some more warning signs?

I'm looking for some "above and beyond" safety tips. I'm a stickler for safety and would never forgive myself if something like a flashlight blew off my hand or burned down my home.

thanks!
 
Re: Beyond the basics for Li-ion safety?

afaik, the released gasses when venting are not poisonous as such (at least in the low concentrations in this circumstance)

You could try drilling a hole in your light to vent, however this would eliminate any water-proofness, and wouldn't make a huge difference anyway... it might only blow up a little bit, or just shoot a 6 inch flame out the side if it went critical.


There are a few horror stories around, but seriously, there are hundreds of thousands of users of these type of cells, and millions, if not billions of people using lithium-ion worldwide. If it were that common, there would be far more stories to tell.

Check list:


1.) Good quality cells - Doesn't have to be AW, but it also wouldn't hurt.

2.) Good quality charger - Can be a cheapy if you want, but you should be aware of how it works, and how it charges. If it trickle charges, or if it will feed too much current etc. Again, better known brands might be better for a reason.

3.) Get a multi-meter - This is pretty much a "must have" item. Doesn't have to be super expensive, or super accurate, but has to be consistant. Get a baseline of your cells when they have charged (around 4.2V or below) and make sure they aren't going over that level on subsequent charges. If they do, consider step 4.)

4.) Chuck cells when they need to be - If a cell is over charged, or discharged, then get rid of it. If you have charged a cell to over 4.25V then its getting a bit dangerous, and if you over discharge a cell, then it is equally dangerous. Chuck it out, and get a new cell. They are cheaper than a new house.

5.) Use protected cells when possible - If you are new to the game, protected cells can be your best friend. Not only do they have safety features built in for when you are using them, but also when charging your cells. Can include overtemp protection, over charge/discharge, and usually include a vent for gasses.

6.) set up a charging area - a lot of us charge our cells in a metal flame proof box on a cement floor for a reason... if you are charging lots of high capacity cells, then you have higher potential for BOOM. Again, not a mandatory thing, but reccomended you at least get an area that you would consider safe to use

7.) Don't leave your cells unattended while charging. I know its a pain in the *** to charge a pair of 18650's for 5 hours, but if you leave them on overnight, you won't know how they are behaving. You should check for the temperature of the cell itself when charging, and check the charger itself. Expect a bit of warmth (10-20 degrees above body temp) but if it is too hot to touch, you got some trouble!

8.) Use the right cell for the job - if you have a high drain device, consider reading up on, and buying some quality IMR cells, if you need a cell that puts out a lower voltage, consider some LiFePO4 cells. Knowing the chemistry of the cells, and their limitations will make using and caring for your cells easier.

Lithium Ion cells have come a long way in safety, but generally the cheapest cells on the market, can also be the most volatile.

Anything I need to add?
 
Re: Beyond the basics for Li-ion safety?

Oh, and having said all this, my first 2 chargers were WF-139's and my first cells were all ultrafires. I now have a lot of different brands, and still call on the ultrafires more often than the AW's
 
Re: Beyond the basics for Li-ion safety?

thanks a lot for the detailed reply!

I plan on going everything on your checklist but had a few questions =)

1. with the multimeter, max charge should be 4.2, and min discharge should be 3.7? Can I use the multimeter to test the battery while it's in the charger or will it give inaccurate result/blow up?

2. I have a little metal box I was considering using to charge in. However, how to people get the cord in there? do they just leave it cracked?

thanks!
 
Re: Beyond the basics for Li-ion safety?

I use AW protected cells, charge in Pila IBC on nonflammable surface, and use a multi meter. Don't give much thought to safety beyond that.

1) If max charge is slightly lower you will get longer life spans from cells. 4.2v is termination a lot of users go with. Charge often as letting voltage dip excessively is bad for service life too. Li-Ions are fine with simple top-offs.

2) Test cells when off charger.

3) You could use a box. Heat is enemy of all charging cells, keep this in mind. IMO a solid surface that will not burn and away from other stuff that could catch is ample.
 
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Re: Beyond the basics for Li-ion safety?

off topic, i could have "burned my house down", and "crashed my car" by making stupid misteaks with ni-cd and ni-mh too.
some of it is just the Power, respect the power.
Because of the ability to have high current flows enough to short a wire out and start stuff on fire, and due to cheap batteries that had no physical protection, or vents or safety of any kind, i had a ni-cd explosion, and nice fire burning in the middle of the room :) and one time due to a short , a battery pack started a nice little smoldering pile in the truck while driving down the road.

it doesnt have to be lithium, to have a lot of power in it, or to be a cheap piece of junk with minimal safety features.
kids have a lot of power too, just like batteries you dont leave them alone when there Playing :)

know the specs, that is one thing, a person might read the "manuel" for something they want to operate correctally, but reading a spec sheet to see how to use the battery correct is not important? if there isnt a spec sheet :) then . . . that is just like getting anything else without a manuel, you use the "Try And Fail" methods till you get it right. the fail part being the problem.
 
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Re: Beyond the basics for Li-ion safety?

Thanks for the replies =)

I have a Dilemma now. I can charge them in my room where I spend most my time, OR in my garage on the concrete floor, but I'm not going to be standing in my garage for 5 hours and don't spend much time in there.

I guess you could say what's more important, location or supervision?
 
Re: Beyond the basics for Li-ion safety?

i had to quit putting them in the garage, when the quantity of solvent, gas, paint, oil, cardboard, wood, and other stuff that would "contribute" if ever an ignition occured, there was some point where the garage was no longer "safer" .
if you have it in a tall open container where it can not "fly out", and a small fire could occur in the container and it would not cause a problem, then it is likly to be very safe.
I guess i would rather see a fire start, then to have it build up before i saw it. but if the fire will be contained, then i dont need to see anything.

odd things to add , often homes do not have smoke alarms in garages, because it can be set off by the car exhaust , here they did not put the smoke alarm in the garage, only the fire sprinklers, and the sprinklers use a different valve releace too, i did not understand. I still have not put a smoke alarm in there, but i got electric doors :p where are my priorities :thinking:

Li-ion does not like to be charged in extreeme cold, but i dont know what temp that is , if it is going to be extreemly cold, then you would want to know that spec item.

i have no intention on making that descision for you, you already know enough to be aware. and it doesnt do any good to be terrified, aware and proactive, beats making error out of fear.
Had one battery in pieces in the garage, using gloves and a face mask and doing all the "right things", while i was testing something else, the garage door opened and the other person drive right over the top of my battery. :wave: sooo, you have to decide. to many factors.
 
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Re: Beyond the basics for Li-ion safety?

I will probably do it my room then, and just have an emergency plan =)

I have a little box that would be perfect...I just don't know how i will run the wire in there. how do you guys that use fireproof boxes do it?

thanks!
 
Re: Beyond the basics for Li-ion safety?

you know that one of the possible RARE problems, is when the solvent gas build up in containment .
or for other batts, hydrogen and oxygen gasses, which just love to recombine quick.
like there is a YouTube with an ammobox, this ammobox had a 3-4inch gaping hole in it, running a dryer hose out, and it still freaking "blew up" harshly because the device "contained" the gasses, and was capable of "increaing the compression" on ignition of the gasses.
that is why tall and open IMO is better than this idea of trying to shut it up in safes and all.

ya got the lithium ok, but you also have a solvent , and oxigination , and its like vaporised gasses kinda thing.
now it is unlikely that you can get the kind of activity that they do when doing it on purpose, but the gasses are still a concideration.
Whoosh is better than Boom, as long as woosh doesnt lead to ketching all the other stuff you left around on fire too.
 
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Re: Beyond the basics for Li-ion safety?

I don't think the cell is ruined if it gets discharged below 3.7 volts, as long as it doesn't stay there long. If you have good cells, good charger, and a volt meter I think its fine to charge li-ion in the house, if you are in the same room. Li-ion are used in laptop battery packs, they aren't terribly dangerous, its just most flashlights don't have the electronics in them to prevent over discharging/charging. Li-ions in a flashlight are also safe if they are single cells, or multi-cells that are matched properly (voltage, manufacturer, purchase date, etc.). From my understanding they "vent-flame" most often while they are charging after being over discharged/over charged.
 
Re: Beyond the basics for Li-ion safety?

Plus
shorts or reverse charge, all good reasons for effective non-shorting Added curcuit protection.
and The internal to the cell itself "mechanical protection" the anode disconnect and PTC device, and for the gassing disconnect to work a good proper seal between the anode dis-connect device and the fixings in the cell.
and internal breakdowns and shorting internally, plating of lithium , which can be via bad cell, or improperly treated, or improperly made cell.
 
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Re: Beyond the basics for Li-ion safety?

llmercll said:
http://www.toyrc.com/li-polymer-battery-safe-charging-bag-white-1880.html

what do you guys think about this? It says lipo so idk
Click to expand...

I have been using LiIon for a a few years and have never had a fire or explosion or even a hot cell, even when doing many charges and discharges.

With that said, I like them and has a couple of them. If an accident happens they will prevent a LiIon "explosion" to throw hot (burning) stuff around. But you might still get a local fire at the sack.

Also note that LiPo for RC use are more likely to explode than normal LiIon cells.
 
Re: Beyond the basics for Li-ion safety?

A lot of useful info for a new guy.

Thanks
 
Re: Beyond the basics for Li-ion safety?

thanks for the infos!!

I got my cells today. I measured their initial voltage and most were between 3.6-3.8. good right? After charging though, it seems my charger brings them up to about 4.21. Is that ok?

thanks!
 
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