Explosions fires rescue at sea

[Cpt Pat]

Originally Posted by billgewater

I assume (surely?) that lithium batteries in cars do not have these problems. These are really seriously large capacity batteries in situations where vibration, collisions etc. are the norm. So why don't we hear about ignition with these battery banks?
If car lithium batteries are relatively safe then why isn't that technology transferable to boats?

On the contrary, the cars do catch fire. Here's a case:

https://www.mercurynews.com/2018/03/...n-highway-101/

And after being towed away, that car caught fire again. Days later:

https://www.mercurynews.com/2018/05/...mountain-view/

[Cpt Pat]

Here are some interesting effects from small lithium batteries, shot by a couple of guys using absolutely no safety protocols:

https://www.youtube.com/watch?v=CUgbmCSmSNY

Imagine an entire pack of those cells "cooking off" in a cascading failure.

Note: these are NOT LiFePO4 batteries being tortured in the above video. They are lithium cobalt batteries, as used in portable devices and electric cars. LiFePO4 batteries used in boat house battery banks have lower capacity for a given mass, but are much safer.

I have heard of a few skippers that have employed used car battery banks. Personally, I think that's insane.

About the only safety precaution available for lithium cobalt batteries is to store and transport them in a discharged state, and charge them in a fire-safe environment under extreme vigilance.

[TeddyDiver]

Originally Posted by roverhi

Really important heads up. Have built up a fairly good range of 12v Milwaukee tools in working on the boat and never thought about explosive possibilities. They are only 12v so probably not as much of an explosion worry as 18v. Still will take more core storing them in the future.

Should have been aware of the fire/explosion possibility of the larger capacity 18v batteries as they can't be shipped by air to our home in Kona. Had to wait more than a month for the slow boat when ordering a battery powered 18v string trimmer.

It's not just the voltage but also capacity. A 12v 6Ah battery is the same in this regard as 18v 4Ah..

[Cpt Pat]

Originally Posted by Montanan

Short video showing the proper method of deploying a fire blanket to suppress a fire. Note especially how the blanket is wrapped around one's hands to provide a shield as you approach to close proximity and smoother the fire.

A fire blanket is a good weapon for fighting a lithium fire, but it would still be a battle with an uncertain outcome. The heat generated approaches the limits of fire blanket ratings: 1000 degrees C, according to FAA tests (quote below). The batteries are apt to rocket around being propelled by exhausted gasses, and the gasses are so toxic that approaching the fire to use the blanket may not be possible.

You can't "smother" a lithium battery fire. It burns without oxygen. But a fire blanket may be useful for gathering up the burning object and tossing it overboard.

The FAA tested several common lithium batteries (not LiFePO4 formulations), and the results were sobering. They had challenges: the fires kept destroying their test jigs. Here's the report: https://www.fire.tc.faa.gov/pdf/TC-TN15-17.pdf

On the subject of temperatures the FAA reported: "Surface temperatures of 18650 lithium-ion cells and ejected contents heated to failure increased with SOC [state of charge] and were as high as 1000ºC at full charge (100% SOC)…"

Here's an article that discusses the challenges directly: https://www.governmenteuropa.eu/lith...-vessel/88384/

The only way I would place large lithium cobalt formulation batteries on a boat would be to place them outside the cabin in a catapult -- so I could fling them overboard.

[Checkswrecks]

Originally Posted by billgewater

I assume (surely?) that lithium batteries in cars do not have these problems. These are really seriously large capacity batteries in situations where vibration, collisions etc. are the norm. So why don't we hear about ignition with these battery banks?
If car lithium batteries are relatively safe then why isn't that technology transferable to boats?

???

Electric car fires are common enough that I'm on an SAE standards committee concerned with firefighting for EVs. I've investigated EVs which have re-ignited multiple times and more than a week after the initial fire. A number of European cities now have what are essentially dumpsters to put a burning car in because that may be the only way to firmly extinguish an EV. Adding salt to the water also provides the ability to deplete the electric charge in what we call "trapped energy" if the crash isolated battery modules. The following page on my website has a spreadsheet with a list of 104 electric vehicle fires, the set of slides shown on the page break down the subject, and the paper about water shows the Euro dumpsters. https://howitbroke.com/downloads All that said, I do see owning an EV in my future before too long.

[Checkswrecks]

Originally Posted by Cpt Pat

A fire blanket is a good weapon for fighting a lithium fire, but it would still be a battle with an uncertain outcome. The heat generated approaches the limits of fire blanket ratings: 1000 degrees C, according to FAA tests (quote below). The batteries are apt to rocket around being propelled by exhausted gasses, and the gasses are so toxic that approaching the fire to use the blanket may not be possible.

You can't "smother" a lithium battery fire. It burns without oxygen. But a fire blanket may be useful for gathering up the burning object and tossing it overboard.

The FAA tested several common lithium batteries (not LiFePO4 formulations), and the results were sobering. They had challenges: the fires kept destroying their test jigs. Here's the report: https://www.fire.tc.faa.gov/pdf/TC-TN15-17.pdf

On the subject of temperatures the FAA reported: "Surface temperatures of 18650 lithium-ion cells and ejected contents heated to failure increased with SOC [state of charge] and were as high as 1000ºC at full charge (100% SOC)…"

Here's an article that discusses the challenges directly: https://www.governmenteuropa.eu/lith...-vessel/88384/

The only way I would place large lithium cobalt formulation batteries on a boat would be to place them outside the cabin in a catapult -- so I could fling them overboard.

Somebody asked what EPIRBs use and Montanan correctly (again) wrote that most are primary (disposable) lithium, which are much less likely to have an initial failure. I previously wrote that you could look this up for yourself by Googling the device followed by MSDS, so here is a link as an example to the MSDS from ACR: http://cdn1.oceansafety.com/3SiGuardianEPIRB_MSDS.pdf

Pat -

I've been at some of those FAA tests in ACY, as well as in Japan, and other places. When with the NTSB, I contracted the UL fire lab located north of Chicago. The tests are either dragged out by smoking over a boring and long period of time, or HOLY **** jaw dropping. Not too many tests are in the middle between boring and stunning.

We went through about $3.6 million of 65 Ah 787 batteries and those cooking off were pretty impressive. A large prismatic would vent with whistling, smoke, and frequently some fire, then it'd just smoke for a while. Then BAM another of the 8 cells would let loose as it heat soaked. The typical time for the set of 8 cells was 30-50 minutes and THERE is a hazard to remember. Just because the event seems to be over the heat is soaking into adjacent cells and they should be treated as live damaged hand grenades. The fire fighter at the initial Boston 787 who got burned made just this mistaken assumption and when a cell failed, the burning electrolyte and plastic sprayed his exposed neck. (Neck gator was out of place) Fortunately his face was covered by the SCBA.

The idea of keeping/charging cells in the stainless sink is one for others to think about. Simple and effective. If unable to get the cell off the boat you have the ability to fill the sink to cool and drown it. Then throw it overboard to prevent outgassing and potential re-ignition.

The fire blankets suggested by Montanan are absolutely a good idea for a number of reasons and not all have to do with batteries. As he wrote, quick use of a blanket contains the problem to a small area. The initial fire (think of the e-bike video) is less able to spread to the varnish, wood, foam, and fabrics which our boats have so much of. The blanket can also give you a means of scooping up whatever is burning to get it overboard. I'm buying one for my boat.

Used lithium car batteries are parted and re-used for a number of other storage products and there are companies which provide that service. A single Tesla can have over 8,400 individual 18650 cells. Unfortunately, it's not that hard to do and there are a lot of people trying to do the same thing, but they don't have the background to build a proper BMS and there've been some nasty fires burning houses down from home-made Power Wall imitations.

There are also people using re-purposed cars cells to rebuild power tool batteries and these are downright dangerous. They are easy to spot on eBay because they are so cheap. I'm with you on trying to keep cobalt based cells off the boat, but sometimes you don't know what is in the casing.

[MV Wanderlust]

Wow! Thanks for sharing your experience. A tense time, to be sure. The most important piece of the story is that you survived. The Coasties did their usual admirable job.

[Island Time O25]

Wow, 2am and at heave to was the worst time for this to happen. That all lives were saved is the most important of that outcome.

Years ago, before I installed a 2000/3000W invertrer, I solved the problem of dying/ageing rechargeable batteries/packs. I started using only 12V tools (not 14.4, 18, 19v, etc) and had them rigged with cigarette plugs with 6-10' cords. As every cabin and the cockpit have the 12v outlets it is easy to use the tools where needed. Still prefer using regular corded tools though.

[sanibel sailor]

I have a fire blanket aboard. I assume it is just thin fiberglass cloth. How conductive are these things? If I grab a hot battery to pitch it overboard, how much handling time can I expect? I have made the mistake of using a moist dishrag to pull something out of the oven. It conducts heat quite well to my surprise.

[flee27]

Looks like they were doing wiring work on the EBike. You can see exposed wire and wire nuts on top of the luggage rack and tools on the ground. Not implying there is no hazard with batteries just wondering if there isn't more to the EBike story than hazardous batteries...

Foster

[JPA Cate]

Originally Posted by sanibel sailor

I have a fire blanket aboard. I assume it is just thin fiberglass cloth. How conductive are these things? If I grab a hot battery to pitch it overboard, how much handling time can I expect? I have made the mistake of using a moist dishrag to pull something out of the oven. It conducts heat quite well to my surprise.

The water in the dishrag turns to steam and the steam burns you. Proper fire blanket is a better answer. Also, there are s/s buckets. One full of sea water would allow you to transport an on-fire battery to the ocean, away from your boat. The ocean's a really big heat sink.

Maybe all homes, not just boat homes, should have a few. I've a sense the rate of this type of fires will be increasing.

Ann

[Montanan]

Originally Posted by Cpt Pat

A fire blanket is a good weapon for fighting a lithium fire, but it would still be a battle with an uncertain outcome. The heat generated approaches the limits of fire blanket ratings: 1000 degrees C, according to FAA tests (quote below). The batteries are apt to rocket around being propelled by exhausted gasses, and the gasses are so toxic that approaching the fire to use the blanket may not be possible.

You can't "smother" a lithium battery fire. It burns without oxygen. But a fire blanket may be useful for gathering up the burning object and tossing it overboard.

The FAA tested several common lithium batteries (not LiFePO4 formulations), and the results were sobering. They had challenges: the fires kept destroying their test jigs. Here's the report: https://www.fire.tc.faa.gov/pdf/TC-TN15-17.pdf


On the subject of temperatures the FAA reported: "Surface temperatures of 18650 lithium-ion cells and ejected contents heated to failure increased with SOC [state of charge] and were as high as 1000ºC at full charge (100% SOC)…"

Here's an article that discusses the challenges directly: https://www.governmenteuropa.eu/lith...-vessel/88384/

The only way I would place large lithium cobalt formulation batteries on a boat would be to place them outside the cabin in a catapult -- so I could fling them overboard.

For a fire to burn, all three elements of the fire triangle must be present: heat, fuel and oxygen. The fire blanket is used to cut off the ambient oxygen supply to the fire, thereby putting it out. The fire blanket must be sealed closely to a solid surface around the fire to be most fully effective. A chemical fire such as can be derived by a lithium chemistry that includes oxygen can self ignite but will be further energized as to rate of combustion [its heat release rate, HRR] if ambient oxygen is availed to aid in combustion. The blanket cuts the supply of oxygen thereby slowing the oxidation. The point of containing a battery fire into a fire proof box [or to use a dumpster to transport a damaged electric vehicle] is to contain the spread of flames and to minimize the availability to ambient oxygen. A fire blanket will contain the flames from spreading and reduce the supply of oxygen to the source of the fire, but the toxic emissions of combustion will not be significantly contained by a blanket for any duration of time. For a small battery one should be able to wrap a battery or the equipment that contains the battery [power tool, computer, phone, radio, charger base] and transport the entire wrapped good to the topside and toss in the water. Trying to wrap and transport a large, heavy battery such as those used on a house bank, well that's going to be problematic, especially since the conductor cables need to be disconnected from the terminals. The standard fiberglass blankets are typically rated for 1,000 C for one minute which should contain most small battery fires, especially for a limited amount of time to gather and toss. And of course the blanket will smoother fires of adjoining combustible materials that the battery has ignited. A blanket could be cooled with water to aid its retaining its rated capacity and fire protection smothering capacity.

One important advantage of LiFePO4 [a.k.a. LFP] over other lithium-ion chemistries is thermal and chemical stability, which improves battery safety. LiFePO4 [a.k.a. LFP] is an intrinsically safer cathode material than LiCoO2 and manganese spinel, through omission of the cobalt, with its negative temperature coefficient of resistance that can encourage thermal runaway. The P–O bond in the (PO4)3− ion is stronger than the Co–O bond in the (CoO2)− ion, so that when abused (short-circuited, overheated, etc.), the oxygen atoms are released more slowly. A slower rate of oxygen release means less oxygen to derive combustion chemistry. This stabilization of the redox energies also promotes faster ion migration.

As lithium migrates out of the cathode in a LiCoO2 cell, the CoO
2 undergoes non-linear expansion that affects the structural integrity of the cell. The fully lithiated and unlithiated states of LiFePO4 are structurally similar which means that LiFePO4 cells are more structurally stable than LiCoO2 cells.

No lithium remains in the cathode of a fully charged LiFePO4 cell. (In a LiCoO2 cell, approximately 50% remains.) LiFePO4 is highly resilient during oxygen loss, which typically results in an exothermic reaction in other lithium cells. As a result, LiFePO4 cells are harder to ignite in the event of mishandling (especially during charge). The LiFePO4 battery does not decompose at high temperatures.



Fire Tests on E-vehicle Battery Cells and Packs.
Sturk D1, Hoffmann L, Ahlberg Tidblad A.
Author information
Abstract
OBJECTIVE:
The purpose of this study was to investigate the effects of abuse conditions, including realistic crash scenarios, on Li ion battery systems in E-vehicles in order to develop safe practices and priorities when responding to accidents involving E-vehicles.

METHOD:
External fire tests using a single burning item equipment were performed on commercial Li ion battery cells and battery packs for electric vehicle (E-vehicle) application. The 2 most common battery cell technologies were tested: Lithium iron phosphate (LFP) and mixed transition metal oxide (lithium nickel manganese cobalt oxide, NMC) cathodes against graphite anodes, respectively. The cell types investigated were "pouch" cells, with similar physical dimensions, but the NMC cells have double the electric capacity of the LFP cells due to the higher energy density of the NMC chemistry, 7 and 14 Ah, respectively. Heat release rate (HRR) data and concentrations of toxic gases were acquired by oxygen consumption calorimetry and Fourier transform infrared spectroscopy (FTIR), respectively.

RESULTS:
The test results indicate that the state of charge (SOC) affects the Heat Release Rate HRR as well as the amount of toxic hydrogen fluoride (HF) gas formed during combustion. A larger number of cells increases the amount of HF formed per cell. There are significant differences in response to the fire exposure between the NMC and LFP cells in this study. The Lithium Ferrous Phosphate LFP cells generate a lot more toxic hydrogen fluoride HF per cell, but the overall reactivity of the Nickel Manganese NMC cells is higher. However, the total energy released by both batteries during combustion was independent of State Of Charge SOC, which indicates that the electric energy content of the test object contributes to the activation energy of the thermal and heat release process, whereas the chemical energy stored in the materials is the main source of thermal energy in the batteries.

CONCLUSIONS:
The results imply that it is difficult to draw conclusions about higher order system behavior with respect to HF emissions based on data from tests on single cells or small assemblies of cells. This applies to energy release rates as well. The present data show that mass and shielding effects between cells in multicell assemblies affect the propagation of a thermal event.

[JPA Cate]

@Montanan:

Thank you very much for so much detailed information.

And, to the OP, thank you for disclosing the event that has brought in so much good information.

Ann

[Paul L]

Originally Posted by Montanan

......

One important advantage of LiFePO4 [a.k.a. LFP] over other lithium-ion chemistries is thermal and chemical stability, which improves battery safety. LiFePO4 [a.k.a. LFP] is an intrinsically safer cathode material than LiCoO2 and manganese spinel, through omission of the cobalt, with its negative temperature coefficient of resistance that can encourage thermal runaway. The P–O bond in the (PO4)3− ion is stronger than the Co–O bond in the (CoO2)− ion, so that when abused (short-circuited, overheated, etc.), the oxygen atoms are released more slowly. A slower rate of oxygen release means less oxygen to derive combustion chemistry. This stabilization of the redox energies also promotes faster ion migration.

.....

Montanan,
Do you work in the Litium battery area professionally?
What is your opinion on LiPO batteries being used as house batteties on cruising boats?

[Michael Cobbe]

It is well known that Lithiumm batteries have exploded in aeroplanes and cars so I don't now why anyone buys them.