Something NOT to do: Fixing bulging LiPo batteries...  - Page 1
Forum section: electronics / projects

author: Hugoneus
author_rank: Frequent Contributor
timestamp: November 06, 2015, 12:22:01 am
content: Sigh...https://www.youtube.com/watch?v=lE9FFy_MbC0&feature=youtu.be&t=219

author: lowimpedance
author_rank: Super Contributor
timestamp: November 06, 2015, 12:33:35 am
content: And he caught a whiff of gas tooLets hope he is not a brain surgeon.

author: rs20
author_rank: Super Contributor
timestamp: November 06, 2015, 12:52:07 am
content: I love it! "The battery is bulging... so I let the gas out. Now it's not bulging anymore! Job done."

author: TheSteve
author_rank: Unknown
timestamp: November 06, 2015, 12:53:05 am
content: This guy is cruising for a Darwin award. It is insane to suggest anyone try this.

author: nuno
author_rank: Frequent Contributor
timestamp: November 06, 2015, 12:56:33 am
content: I remember having seen people do that at endless-sphere, with bigger cells (electric bicycles), although maybe not LiPO but LiFePO4 or one of the other "safer" lithium based battery chemistries.

author: crispy_tofu
author_rank: Super Contributor
timestamp: November 06, 2015, 01:46:27 am
content: Nopenopenopenopenopenope.

author: LabSpokane
author_rank: Super Contributor
timestamp: November 06, 2015, 01:57:48 am
content: QuoteNo.. You have screws loose. No doubt about it.

author: calzap
author_rank: Frequent Contributor
timestamp: November 06, 2015, 02:13:53 am
content: Was curious what gases might be released from a misbehaving LiPo. Found an answer athttp://www.rechargebatteries.org/wp-content/uploads/2013/07/Li-ion-safety-July-9-2013-Recharge-.pdf. Pic below is a table from that website. It's the first and last items that are of toxic concern. Carbon monoxide (CO) is colorless, odorless, flammable, and highly toxic. Hydrogen fluoride (HF) is colorless, corrosive, highly toxic, and definitely not odorless. The C4 compounds, depending on their identity, could contribute to toxicity and odor.I think the above is based on the assumption the battery does not actually burst into flames. If that happens, additional toxic gases will be formed.Mike in California

author: marshallh
author_rank: Unknown
timestamp: November 06, 2015, 02:21:34 am
content: I've smelled it, it's like a very acidic/metallic smell that is about 2x stronger than a sharpie. 0/10 would not smell again

author: Nerull
author_rank: Frequent Contributor
timestamp: November 06, 2015, 02:40:56 am
content: Quote from: calzap on November 06, 2015, 02:13:53 amHF is very nasty. As a gas, it doesn't do much...until you breath it in, at which point it dissolves in the moisture in your lungs and forms highly corrosive hydrofloric acid.

author: JacquesBBB
author_rank: Frequent Contributor
timestamp: November 06, 2015, 03:16:34 am
content: He should have done it outside, but aren't you all overreacting ?A battery cell may have 1or 2 cc of gas. That is at most 1 ml of CO.An average 2l car, stopping at a red light, at idle regime will exhaust many nasty gas, and among them about 2% of CO, that is at 500 rpm 20l of CO per mn.Things are worse when you start your car in a garage.

author: pickle9000
author_rank: Super Contributor
timestamp: November 06, 2015, 03:59:53 am
content: Just as a general question.How many people have a proper fire extinguisher and safety glasses at their bench?

author: pickle9000
author_rank: Super Contributor
timestamp: November 06, 2015, 04:02:26 am
content: Recently posted

author: miguelvp
author_rank: Super Contributor
timestamp: November 06, 2015, 04:07:00 am
content: Quote from: pickle9000 on November 06, 2015, 03:59:53 amI do, but my safety glasses are for lasers and the fire extinguisher is in the kitchen pantry, very next door from my home office.But I don't deal with dangerous chemicals that warrant safety glasses.

author: helius
author_rank: Super Contributor
timestamp: November 06, 2015, 04:17:48 am
content: Quote from: JacquesBBB on November 06, 2015, 03:16:34 amFor cars equipped with working catalytic converters, the levels of CO in the tailpipe gas are around 1000 ppm, or 0.1%. For short-term exposure in ventilated areas this would not be expected to cause any effect, based on the conservative (10x under rated) TLV-STEL of 400 ppm. In an enclosed area like a garage, the potential exists for higher levels, but nothing highly dangerous. On the other hand the punctured LiPo vents its gas under pressure and, in the video, very close to the user. It's not clear how much gas is present, but since it is under pressure it must expand when escaping.With all that said, I don't think CO is the main danger in venting batteries. The TLV for HF is 0.5 ppm (500 ppb), and the consequences of fluorosis are more severe than acute CO poisoning.

author: pickle9000
author_rank: Super Contributor
timestamp: November 06, 2015, 04:49:26 am
content: Quote from: miguelvp on November 06, 2015, 04:07:00 amSo have a look at the video where AvE blows up a thing. First he is wearing gloves, I know he has a fire extinguisher nearby, I also know he wears safety glasses. He is used to things going wrong and has a plan before he starts (disconnect the power first). He has all his fingers. That does not mean he can't get hurt, the unexpected can happen anytime.He may be a bit of a novice to electronics but a professional when it comes to safety. You can tell he comes from an industry in which accidents kill.As for the guy playing with the battery. No plan for when things go wrong, not even a bucket of sand.

author: aargee
author_rank: Frequent Contributor
timestamp: November 06, 2015, 04:51:39 am
content: Quote from: crispy_tofu on November 06, 2015, 01:46:27 amProbably not the right word when losing the 'N'..."openopenopenopenopenope."

author: CatalinaWOW
author_rank: Super Contributor
timestamp: November 06, 2015, 04:55:11 am
content: Agree this is a bad thing to do. But the guy apparently didn't die. Doing some numbers shows why. A smallish lab would be roughly a 3 meter cube. The .5 ppm TLV in that room would be about 14 ml. Not very much, BUT, this TLV has a similar safety factor to the clinical threshold, so it really would require release of about 1.4 liters to do real damage. And as others have mentioned, the odor and feel of HF is such that you would stop breathing immediately limiting your dose. A bigger lab, a little better ventilation would help, and a 1.4 liter release doesn't really seem likely. While a puffed cell is pressurized it is not several atmospheres of pressure and there just isn't that much volume inside the cell. It is lighter than air and will tend to rise above the breathing level as the first step in mixing with the room air. On the other hand, if you had your face up against the cell while it was punctured the HF would not be well mixed, so local concentrations could be very high.All in all, it seems that this is an unlikely mechanism to do any Darwinic culling of the species. Most likely no real serious affects, and reduced lung capacity would be the most probable effect when something bad did happen. No more triathlons for the nerd experimenter.

author: AF6LJ
author_rank: Unknown
timestamp: November 06, 2015, 05:05:11 am
content: This guy is a piece of work.

author: tooki
author_rank: Super Contributor
timestamp: November 06, 2015, 10:58:26 am
content: Quote from: Hugoneus on November 06, 2015, 12:22:01 amWell, the video was 3 years ago and he doesn't appear to have died, since he's still making videos. Such as him singing "Call Me Maybe" in Japanese.

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 06, 2015, 11:57:28 am
content: Quote from: Hugoneus on November 06, 2015, 12:22:01 amthanks for the great tips on battery bulging problem solving. will do the next time i have the problem... ps: i inhaled more toxic gas than that for the past ~20 years...

author: mikerj
author_rank: Super Contributor
timestamp: November 06, 2015, 01:02:49 pm
content: Quote from: Mechatrommer on November 06, 2015, 11:57:28 amThat explains a lot...

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 06, 2015, 01:26:03 pm
content: Quote from: mikerj on November 06, 2015, 01:02:49 pmno it isnt... healthier people died earlier than me... i'm not bragging, but i think that is not the equation...

author: DanielS
author_rank: Frequent Contributor
timestamp: November 06, 2015, 06:21:22 pm
content: Quote from: helius on November 06, 2015, 04:17:48 amIf the cell bags can be easily squeezed by hand to move the gas around prior to poking it, as it does in the video, the pressure is only slightly above ambient, just enough to lift the bag from the cell.In the case of my old cell phone's dead battery, pressure inside the cell is so high that I cannot press it down by a noticeable amount by hand. Now that one might be scary to poke.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: November 06, 2015, 10:15:04 pm
content: Pressure can get higher. I have had one burst from its own internal pressure. Still only multiple psi, not tens of atmospheres.The trick with Lithium chemistry batteries is get the right balance. Not excessive fear. Not glib unconcern.It is kind of like gasoline (petrol for those who speak that language). It really is nasty stuff. Poisonous. Flammable. Explosive under certain conditions. Nasty combustion products. But with precautions simple enough that the vast majority of knuckle draggers can implement them it is safe enough that vast numbers of those same knuckle draggers survive using it daily over most of their lives.

author: Nerull
author_rank: Frequent Contributor
timestamp: November 07, 2015, 12:32:48 am
content: Quote from: Mechatrommer on November 06, 2015, 11:57:28 amAren't you the guy who was freaking out over the remote possibility that low level RF exposure causes cancer?

author: crispy_tofu
author_rank: Super Contributor
timestamp: November 07, 2015, 12:35:32 am
content: Quote from: aargee on November 06, 2015, 04:51:39 ameek.Quote from: pickle9000 on November 06, 2015, 04:49:26 am+1

author: EEVblog
author_rank: Unknown
timestamp: November 07, 2015, 02:19:36 am
content: I don't even need to watch the video to know this is going to be wrong...

author: Mechatrommer
author_rank: Super Contributor
timestamp: November 07, 2015, 04:49:42 am
content: Quote from: Nerull on November 07, 2015, 12:32:48 amme?!talking about asking the wrong guy... ask that question again to those inhalophobia and electrophobia around here..

author: amyk
author_rank: Super Contributor
timestamp: November 07, 2015, 05:06:01 am
content: Quote from: CatalinaWOW on November 06, 2015, 04:55:11 amThere is absolutely no HF released if the cell does not combust. The list of substances posted on the previous page is "emittedduring the thermal run-away". On the other hand, he probably inhaled vapours of chemicals likedimethyl carbonate,diethyl carbonate, andethyl acetatewhich are not particularly toxic (and the latter one actually smells quite pleasant - it's the same compound in pear flavouring) - the main danger is that they're flammable.

author: helius
author_rank: Super Contributor
timestamp: November 07, 2015, 05:26:10 am
content: Quote from: amyk on November 07, 2015, 05:06:01 amGood catch, but there might be some decomposition without igniting or sustaining a visible flame. The fluorine content of cells seems to vary widely, with some using "fluorine-free electrolytes" and other experimental cells using fluorine for the whole cathode, or as a charge shuttle or additive. But the main generator of HF might still be decomposition of PTFE insulators.

author: calzap
author_rank: Frequent Contributor
timestamp: November 07, 2015, 05:55:00 am
content: Quote from: amyk on November 07, 2015, 05:06:01 amThe table I posted fromhttp://www.rechargebatteries.org/wp-content/uploads/2013/07/Li-ion-safety-July-9-2013-Recharge-.pdfwas gases from thermal runaway without combustion. With combustion, the gas mix changes to the list in the pic below. A lot less CO, which burns, but still not a breath of springtime.Mike in California

author: amyk
author_rank: Super Contributor
timestamp: November 07, 2015, 04:12:51 pm
content: Quote from: helius on November 07, 2015, 05:26:10 amEither way, I very much doubt the gas in a bloated cell that's not burning, or so hot it's about to, is going to contain any HF. Some searching reveals that the gases are mostly oxygen/hydrogen, so it is flammable, but if you don't have any ignition sources (like shorting the cell while puncturing it) it shouldn't spontaneously ignite. The cell should also be discharged to minimise the risk.More talk of "burping" lipo cells here:https://endless-sphere.com/forums/viewtopic.php?f=14&t=22650

author: Radio Tech
author_rank: Frequent Contributor
timestamp: November 07, 2015, 04:16:49 pm
content: Quote from: EEVblog on November 07, 2015, 02:19:36 amNo worries mate, he just needed to expel a little gas