Skinnyone Posted September 12, 2016 Posted September 12, 2016 Any battery no matter what chemistry (Ni-Mih,Ni-CAD, Li-ION, LI-PO etc) should not be left unattended whilst on charge, there may be an internal fault (being a damaged cell with irregular internal resistance which will generate more heat than normal) this can be created by depleting the battery past its safe minimum voltage - or overuse or an external fault like the pack has been dropped and damaged one of the cells. There may also be fault in the charger itself, if it doesn't cut off the charging at the preset voltage then the battery will keep on "getting filled up" but the problem is that any cell/battery is like a glass of water, you can only pour so much water into a glass until it overflows - same principle in a charging scenario - you can only put so many milliamps (water) into a cell before it needs to release the excess (overflow) or read explode...
Plentipotential Posted September 12, 2016 Author Posted September 12, 2016 Please name the supplier if possible. As one of the bigger suppliers of lights (Magicshine) in SA I would definitely want to know if this was a battery I supplied. I have supplied thousands of batteries over the years and I am not aware of a single potentially dangerous failure, but I would like to know if there was one! Mail sent.
Plentipotential Posted September 12, 2016 Author Posted September 12, 2016 Any battery no matter what chemistry (Ni-Mih,Ni-CAD, Li-ION, LI-PO etc) should not be left unattended whilst on charge, there may be an internal fault (being a damaged cell with irregular internal resistance which will generate more heat than normal) this can be created by depleting the battery past its safe minimum voltage - or overuse or an external fault like the pack has been dropped and damaged one of the cells. There may also be fault in the charger itself, if it doesn't cut off the charging at the preset voltage then the battery will keep on "getting filled up" but the problem is that any cell/battery is like a glass of water, you can only pour so much water into a glass until it overflows - same principle in a charging scenario - you can only put so many milliamps (water) into a cell before it needs to release the excess (overflow) or read explode... Appreciate the heads up. Thanks
Skylark Posted September 12, 2016 Posted September 12, 2016 Those are 18650 li-ion cells, looks like the cell balancing or battery connecting wire has overheated and burnt the plastic wrapper on each cell. Always try use high quality cells and a reputable charger.
PhilipV Posted September 13, 2016 Posted September 13, 2016 Come to think of it, if I'm charging my light batteries, or my phone, laptop etc, and the pawpaw hits the fan, how does one handle the resultant burning? Foam fire extinguisher? Water? Put a metallic container like a bucket or a pot over it to contain and hopefully smother it? Sent from my LT30p using Tapatalk
Vetseun Posted September 13, 2016 Posted September 13, 2016 Latest Samsung Note 7 has experienced a few battery detonations and is consequently banned from certain airlines....There is a lot of juice in those Li-ion / Li-po bike light batteries. Quite a bit more than the average motorbike battery in fact. They are subjected to serious vibration and the cables also prone to fatigue from flexing during a ride. I had one where one of the wires simply broke.....it could just as easily have shorted against the other wire and started a fire.Inspect often and be careful. Only use the dedicated charger that was supplied with it.Sent from my SM-G935F using TapatalkWas so excited about the Note 7. Now I have to wait for it. Hope they sort the battery issue out very fast.
JXV Posted September 13, 2016 Posted September 13, 2016 Was so excited about the Note 7. Now I have to wait for it. Hope they sort the battery issue out very fast.Me too. Had one on order....ended up with S7edge. Sent from my SM-G935F using Tapatalk
Barend de Arend Posted September 13, 2016 Posted September 13, 2016 Any battery no matter what chemistry (Ni-Mih,Ni-CAD, Li-ION, LI-PO etc) should not be left unattended whilst on charge, there may be an internal fault (being a damaged cell with irregular internal resistance which will generate more heat than normal) this can be created by depleting the battery past its safe minimum voltage - or overuse or an external fault like the pack has been dropped and damaged one of the cells. There are a couple of batteries that are always unattended: alarm batteries, UPS batteries,... It's simply not possible to guard them all.
JXV Posted September 13, 2016 Posted September 13, 2016 Come to think of it, if I'm charging my light batteries, or my phone, laptop etc, and the pawpaw hits the fan, how does one handle the resultant burning? Foam fire extinguisher? Water? Put a metallic container like a bucket or a pot over it to contain and hopefully smother it? Sent from my LT30p using TapatalkLithium fire is hectic. You need to exclude oxygen but water makes it worse as it reacts extremely violently with the alkali metals. Foam has water in it. So sand would probably be best. Smother it and absorb the heat.....oh, and unplug from the energy source. Sent from my SM-G935F using Tapatalk
Neverfit Posted September 13, 2016 Posted September 13, 2016 When did Samsung start making cycling lights....
JXV Posted September 13, 2016 Posted September 13, 2016 When did Samsung start making cycling lights.... Point taken.....battery tech is similar though. Sent from my SM-G935F using Tapatalk
Skinnyone Posted September 13, 2016 Posted September 13, 2016 Like JXV says NEVER use water, I got thrown out of chemistry class in school for messing around with lithium and water, and having deliberately detonated a couple of Li-Po batteries I can attest that it is not a situation to take lightly. Sand or anything else that will smother the fire and exclude the oxygen is your best bet. I know someone who lost his entire house + 2 cars because of a battery fire - he literally got out with his wallet and phone.. @Barend, I fully agree, the alarm and gate batteries are always on charge but those are much, much less volatile lead acid batteries - still can cause a fire yes but a lot "tamer" than Li-Po. I have been driving a car where the alternator failed and fried the battery and electrics, luckily I knew the warning signs - a strong smell of sulpher. The thing with lead acid batteries is that generally the wires connecting to the battery will get hot and cause the fire, not the actual battery exploding. Remember that Lithium if exposed to oxygen it will self ignite quite violently - now you add water into the mix which as we know has oxygen as well....now in a battery the Lithium and polymer stores extra energy and bring that to the mix...well just search Li-Po fire on YouTube...
Bobbo_SA Posted September 13, 2016 Posted September 13, 2016 Come to think of it, if I'm charging my light batteries, or my phone, laptop etc, and the pawpaw hits the fan, how does one handle the resultant burning? Foam fire extinguisher? Water? Put a metallic container like a bucket or a pot over it to contain and hopefully smother it? Sent from my LT30p using Tapatalk Lithium reacts with water hence any foam etc type will be a bad idea, on the plus side the battery fire normally only last a few seconds as it vents (Ok, its extremely hot and can send a flame out to around 2m depending on the capacity / stored energy), you need to be able to put out everything else in the surroundings that would likely be on fire by the time you get to it. Edit: Bit slow but the point is still valid, by the time you get to the pack the lithium part is likely to be burnt out, the rest of the house may be on fire in which case a foam based extinguisher may still be useful.
Bobbo_SA Posted September 13, 2016 Posted September 13, 2016 Point taken.....battery tech is similar though. Sent from my SM-G935F using Tapatalk Most 18650 cells are manufactured by Samsung.... #Justsayingyouwerecorrect...
gogo@ Posted September 13, 2016 Posted September 13, 2016 Saw this the other day just before this thread was started - have a look at the photos... basically lost everything in their flat. http://www.singletracks.com/blog/mtb-interviews/a-cheap-chinese-bike-light-nearly-burned-down-this-riders-house/ "I heard something cracking—it had fallen somehow from the stool itself and it had fallen behind the lazy boy. I noticed just a little flame and a little smoke coming from behind the lazy boy itself. I didn’t really know what to do—I kinda panicked. I ran around in circles for a split second and then I ran downstairs and I grabbed a bowl, filled it up with water, and I threw it on the fire. It really didn’t do a whole lot. I thought I honestly could put the fire out, I really did. I ran downstairs and—can’t really remember how many times I ran up and down, I know it was at least twice. But the last time, I remember I threw the water and I was just like, “I have to start getting stuff out. I’m never going to put out this fire.”By the third time I got up there the fire had grown so much, and I could hear the light—it was continuing to explode."
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