vol

The latest news reports, while reporting that Malaysia just admitted (belatedly) that the flight MH370 was carrying lithium batteries in its cargo hold, mention that lithium-ion batteries have caused 140 mid-air incidents in the last 20 years. I didn't know about this. How can the batteries be on fire by itself? How easy? Don't many passengers carry laptops/mobile phones with lithium batteries on airplanes all the time?

RoadTire 

LiOn is pretty reactive, and if you do things like put a overly discharged battery in series with a fully charged battery, they get pretty hot and vent a lot of gas and can flame on. On BudgetLight forums there are lots of warnings to just be nice to the batteries and take some precautions when charging. Over discharge, overcharge causes problems. Shorting them out really causes problems. High capacity and low internal resistance give them excellent high current capability.

JB01245

18650 cell -
overcharged then
crushed in vise
skewered with a screwdriver
pounded - crushed-mangled by heavy hammer





*****

RoadTire 

JBO that's pretty radical. Reminds me of the T2 after it was shot with the explosive grenade. LOL. I like it.

Go to about 6:20 - 6:45 and see what happens when one actually does light up. Like poisonous fireworks in your house. Any high-current battery can be dangerous. And if nothing else, this guy is a pretty good hack.

lopek77

Every battery can blow when too hot, overcharged or damaged. Lithium batteries release gases, and that's why they shouldn't be in a closed containers.
If they blow, and they are in let's say metal body flash light - you have a pipe bomb, and it will hurt.
High quality lithium batteries will be relatively safe to use, but many of us are using batteries or light sets from China. EBay deals are so sweet that are too hard to pass.
I always charge mine on fire proof surface, never leave the house when they are charging, and I never overcharge them. Both overcharging and discharging to less than 5-10% is not a good idea.
When on my bike - I keep my battery pack under my seat, away from my face.
There is a ton of online resources about these batteries. Overall, they are considered pretty dangerous, but when tested its not always the case.

vol

How could over discharge cause explosion/fire?

Litespeedlouie

What I've heard is that one cell can easily discharge more than the others and go under nominal cell voltage, and they'll get a reverse polarity charge from the other, not-as-discharged cells in the pack. That seems to be a prime suspect in explosive discharge of some chemistries of LiIon (there are several). And the gases are -very- toxic (hydrofluoric acid?).

Some flashlight guys now insist on single cell LiIon lights, usually using 18650 cells.

Also, regular fire extinguishers won't put these out.

If you look at the TSA site, I believe passengers are limited to how much LiIon batteries they can carry on, by weight. I think this accommodates normal phone and laptop use. I suppose they figure at least they'll know if a battery fails in flight, although it would appear your problems aren't over.

People like pro videographers are forced to juggle their large LiIon packs between carry-on and luggage, I think.

These batteries are jugs of highly reactive chemicals. I'd hate to see a palletload in a plane get knocked around by an airpocket.

vol

Thanks for the explanations. Never been aware of such dangers on flights (surprised there were not more accidents caused by the batteries).

01 CAt Man Do

I really don't know why people worry so much about Li-ion batteries. Everything made can malfunction. Take cars for example. Cars carry explosive fuel. Very rare for a car to burst into flames but it happens. I know this for certain because I've seen cars on the side of the highway sitting with flames coming out ( at least 3-4 times in my lifetime ). Does this mean I'm not going to drive a car because they can malfunction and catch fire. Of course not. You put all the facts into perspective and decide that because such occurrences are so rare you will continue to use the car, battery, heater, stove....whatever.

However....I do draw the line when it come to aircraft. Personally I'm not worried about the guy sitting next to me with the laptop unless the batteries in it are drilled out and filled with nitroglycerin. Not to mention I read just the other day that the airlines keep secret lists on which International airlines have poor maintenance standards. Oh I'm not saying I wouldn't get on a airplane to go somewhere but if I do I'm getting my Doc to prescribe me some heavy weight anti-anxiety drugs. ( or just use more of what I already have. ) In the mean time, until they figure out what happened with that "lost jet ) ehhhhhh, I don't think me's-a-getting on a plane anytime soon, capiche.

009jim

I guarantee if ladies needed lithium batteries for personal hygiene they would be legal to carry on board. Note that acetone is not legal, but nail polish remover is!

phoebeisis

I had a cheap chinese battery "blow up" in a flashlight late one night
Middle of the night I hear a pop- and "see" a green or maybe blue flash-
wake up-some acrid smoke in room-and a flashlight burning(rubber coated) near the bed

What happened-the bulb suddenly went bad-no light-while I was using it a few hours earlier
But I didn't turn-push the rear switch-OFF
the bulb burned out-but somehow it shorted for a few hours until enough heat built up-and POP- it blew the headlight off the tube
Nasty surprise- cheap chinese 123 batteries- 3.0 or 3.7 volts
Nice-expensive flashlight unfortunately
Yeah they will sorta explode-produce plenty of heat if no reaction energy is removed(no light)-it all just sits in the battery

no motor?

Yes, avoiding these batteries is about as hard as avoiding computers these days. They're all over these days, and usually don't cause any problems. And when they do, the batteries are either used in ways they weren't designed to or counterfeit batteries found in items like those too good to pass up internet deals like the $15 Magicshine clones.

davidad

https://www.batteryuniversity.com/index.htm

davidad

You know that they are the same?

RoadTire 

I don't think anyone here is overly worried ... just a discussion and awareness. I use LiOn flashlight for night riding, and it's also my EDC in my backpack, but I chose a single cell partially to simplify / minimize the risks of multi-cell lights. I also use protected cells for the same reason. I don't suggest these lights to anyone that wishes to treat the cells like any-'ol-alkaline battery.

Regarding your comment about the dangers of cars catching fire - awareness of the danger is key. I just watched a couple-year-old Discovery channel doco that included info about cars catching fire. What I had forgotten, or was somewhere deep in my hindbrain, was how static potential differences between a gas can and the fuel nozzle can cause a spark just as you start to fill the can. Whoops! So I guess I will pay just a bit more attention from now on.

fietsbob

OK start a 1 to 10 scale Poll and then a vote can be taken.

vol

I would hope the potential hazard of lithium batteries be more of an everyday common knowledge among all users of electrical devices.

Also hope the manufacturers invent some safer batteries.

I have some unused battery packs of 18650x4 sitting there and I just recharged all of them for about half hour to make them stay partially charged. I guess it's a good idea to periodically recharging them slightly if they have not been used?

009jim

Yes - nail polish remover is 100% acetone. Check it out next time you go to the drugstore!

RoadTire 

Yes, and hopefully you are using a balance charger. From what I have read the life span of LiOn is about 2 years no matter how many times they are charged, so best to check the voltages and keep them getting too discharged.

RoadTire 

I don't know if 100% for all nail polish removers, but it sure is the active component. Ya can smell it a mile away. If I had any brains I will offer to refill my daughters nail polish for half-price, or at least dinner. But for some reason I think I already told her to just go buy a small can of acetone.

davidad

I use acetone to remove the mold release from my tubes before I patch them.

davidad

The only time I have had a problem with one of my batteries is when I dropped it and it damaged the protection circuit. I just soldered on a new one.

RoadTire 

I was wondering about that. Good to know. Use acetone for cleaning wood just before staining to remove any traces of oils. ...wait, this is a bike forum and the post was batteries. How did we get to acetone?

noglider 

How does one overcharge a LiIon battery? I wait for the LED to go from red to green. Is leaving it in with the green light sufficient to overcharge it?

01 CAt Man Do

As with most smart chargers, when the led goes from red to green the charging process is over. As long as nothing is wrong with the charger the battery will no longer be charging. Still, I only charge stuff ( mostly ) when I'm home. Chargers have been known to go up but usually when that happens it just means they will no longer charge.

A couple years ago I had a cheap Ultrafire WF(type) two bay single cell charger go up. I could smell the acrid smell of burnt plastic and decided to toss it. Last year my single cell ( 26650 ) charger went up in like fashion. This is one of the reasons why I always recommend using a charger with a surge protector. Now I just need to follow my own advise. In my area, voltage surges are pretty common place. I don't plug up any of my more expensive stuff without a surge protector.

Anyway Tom, I would take the batteries off the charger when done and then unplug the charger, just to be on the safe side. Otherwise the batteries should be fine once the light turns to green. Doesn't hurt to play it safe.