Lithium battery fire extinguisher???

[voyager35]

I have Victron Lithium batteries on my boat and was looking to upgrade the fire protection with a special lithium battery fire extinguisher.
However on reading the information about them I dont see how it would work on my boat as the contents need to smother the battery.
The batteries are housed in a strong plywood box with a few fairly inaccessible holes in the sides for wire access.
If the worst happened and the batteries do catch fire how would the 'special 'foam in the extinguisher smother the battery fire when the box is surrounding them.
If the fire is bad enough to have burnt the box away there is no way I would be lifting the floor boards up to gain access to the compartment

 

[Stemar]

No expert, but from what I can gather, the best advice I could give would be to make sure your battery management system is effective, and don't keep the liferaft in the same locker.

However, LiFePO batteries are very unlikely to catch fire. The scare stories are almost exclusively from other Lithium chemistries and, while specific extinguishers are available, and they might deal with a phone or laptop, I'm far from convinced that anything that could be reasonably carried on a boat would deal with a few 100AH of LI batteries going pop

 

[Refueler]

Fire EXTINGUISHING of Lithium is extremely difficult and even Fire Service say they 'contain' the fire ...

Problem is that Lithium batterys - regardless of chemistry are self sustaining with regard to fire and even complete smothering will not g'tee extinguishing. I am sure someone will argue that - but it is FACT shown by actual fires.

Its a problem that we live with - although much smaller batterys for our models - LiFePo4 / LiPo / LiCo - all have resulted in a few cases of house fires / garage fires etc. We use ammo box's .. special charge fire resistant bags ... fire resistant safes ... all sorts to contain the batterys when charging and transport to from field after charging.

LiFe (incl LiFePo4) are much safer of course - but ALL batterys have possibility and need to be treated with respect.

 

[Trident]

There are specific LFP extinguishers available from about £50 but in reality LFP will not burn - what will if you have electrical faults is the plastic casing, the wires etc like with any electrical fire . Obviously this should never happen if done right but I would go with a simple clean agent automatic extinguisher in the compartment as this will put out any ancillary parts that burn . Just be sure to use a good BMS and proper Class T fusing and you'll never have an issue that results in fire due to the LFP

It's a common worry these days. I make and install these professionally and its always surprising when I find poor crimps, loose terminals, inadequate fuses etc on the systems I am replacing, that these common causes of fire never occur to owners

 

[Pye_End]

From what I read and hear outside of this forum, it is unlikely that an LFP will be the cause of a fire. However, if a separate fire were to light an LFP, then you have a problem. So fire extinguishing seems to be more focused on stopping a non-LFP local fire, or of evacuation.

Quality components for the LFP is probably always good advice, though don't know if poor quality BMS or BMS failure, for example could cause an LFP fire. Perhaps others here can answer this.

Would flooding cause an LFP fire?

Serious problems on boats can stem from multiple failures, perhaps unconnected - under what conditions (other than subject to high heat) would an LFP be on fire?

 

[PaulRainbow]

From what I read and hear outside of this forum, it is unlikely that an LFP will be the cause of a fire. However, if a separate fire were to light an LFP, then you have a problem. So fire extinguishing seems to be more focused on stopping a non-LFP local fire, or of evacuation.

Quality components for the LFP is probably always good advice, though don't know if poor quality BMS or BMS failure, for example could cause an LFP fire. Perhaps others here can answer this.

Would flooding cause an LFP fire?

Serious problems on boats can stem from multiple failures, perhaps unconnected - under what conditions (other than subject to high heat) would an LFP be on fire?

If an LFP cell in a fire it could melt but wouldn't pose any more of a threat than anything else that's on fire.

Flooding should not cause a fire.

 

[Trident]

^^^ What he said! They've tried to melt LFP cells with blow torches, driven nails through them, shot them (well what do expect in the USA) and dropped them in water and these things just wont burn on their own. In a fire they may melt, some small noxious gases may be given off but again, the flammable and noxious plastic parts will be far more of an issue with fire or poisonous fumes. I

 

[Pye_End]

If an LFP cell in a fire it could melt but wouldn't pose any more of a threat than anything else that's on fire.

https://static1.squarespace.com/sta...ection_Guidance_for_Lithium_Ion_Based_ESS.pdf is worth a read.

 

[Pye_End]

In a fire they may melt, some small noxious gases may be given off

Like hydrogen.....

 

[lustyd]

Like hydrogen.....

Hydrogen isn't a noxious gas, and in a fire would burn anyway in a fairly controlled manner as quickly as it's produced.
It's almost impossible to make an LFP battery generate hydrogen in the real world. Unless you submerge it in water, in which case it might generate some but still considerably less than a lead acid battery with a problem.

 

[Refueler]

https://static1.squarespace.com/sta...ection_Guidance_for_Lithium_Ion_Based_ESS.pdf is worth a read.

The document supports the fact that extinguishing of Lithium based fires is difficult .. the document main point being suppression and prevention of fire spread.

^^^ What he said! They've tried to melt LFP cells with blow torches, driven nails through them, shot them (well what do expect in the USA) and dropped them in water and these things just wont burn on their own. In a fire they may melt, some small noxious gases may be given off but again, the flammable and noxious plastic parts will be far more of an issue with fire or poisonous fumes. I

Try this video ... and remember that he said he shorted the terminals etc - so that battery is basically near discharged ......

That is only one example video out of many online of a LiFePo4 actually combusting ... and this one has Aluminium case - not plastic ... so can you tell me where the fire is coming from ??

 

[Dockhead]

It's very hard to get LiFePo4 into thermal runaway, but it's not impossible, and it is exceedingly nasty if it occurs.

I have an automatic F-gas extinguisher in my battery box. One use and not that expensive.

And I think one needs a lithium-rated portable extinguisher on board.

What is characteristic of fires with LiFePo4 is extreme outgassing. Might be worth having one of these on board as well: Lithium Fire Intervention Mask: The Ultimate Mask for Smoke Incidents

 

[lustyd]

What is characteristic of fires with LiFePo4 is extreme outgassing. Might be worth having one of these on board as well: Lithium Fire Intervention Mask: The Ultimate Mask for Smoke Incidents

Or just be outside. Realistically any fire on a plastic boat is immediately life threatening so unless you can put it out immediately, leave.

 

[Pye_End]

Hydrogen isn't a noxious gas, and in a fire would burn anyway in a fairly controlled manner as quickly as it's produced.

Indeed. I was focusing on the effect of fire in the first instance, but glad that you and Trident also point out that there are some pretty nasty gasses which also can come from a burning battery. Probably plenty of other throughout the boat as well.

It's almost impossible to make an LFP battery generate hydrogen in the real world. Unless you submerge it in water,

The hydrogen comes from the battery, in a fire. Lithium Positive and Negative Insurers post 209 for link.

 

[lustyd]

The hydrogen comes from the battery, in a fire. Lithium Positive and Negative Insurers post 209 for link.

Not this again. It’s extremely difficult bordering on impossible to make that happen in the real world and in a fire would be totally irrelevant. You’d get more hydrogen from electrolysis from any water present.

 

[William_H]

Boeing turned to lithium batteries some years back. After some concerns they chose to house the batteries in stainless steel case to contain any fire. Which might be the best clue for OP. Double layered with space would be better. ol'will

 

[lustyd]

Boeing were using lithium ion batteries not LiFePo4. They did this because they were lighter and later regretted it.
The batteries won’t be the source of fire so stainless housing is no more necessary than a stainless diesel tank, gas locker, or petrol can. Most of which are plastic on modern boats.

 

[Refueler]

Boeing turned to lithium batteries some years back. After some concerns they chose to house the batteries in stainless steel case to contain any fire. Which might be the best clue for OP. Double layered with space would be better. ol'will

Boeing were quick to change to Li batts and failed to create the full system needed .... there's plenty of info about it.

Strange that big Company's with all their R&D make stupid mistakes ... same as Samsung with their phone batts ...

 

[Pye_End]

Not this again. It’s extremely difficult bordering on impossible to make that happen in the real world and in a fire would be totally irrelevant. You’d get more hydrogen from electrolysis from any water present.

Risks from LFP's, from the various links posted, are clearly not zero (and before you make the point, I am not claiming you say it is zero). Much the same as other aspects of boating. We all 'risk manage' boats and items, but are content with the risks dues to design, quality, maintenance and mitigation. Pratchett's 'million to one chance' may well be applicable to somebody someday.

So it seems perfectly natural to me to ask 'under what circumstances will an LFP cause a problem', and 'if it happens when I am at sea, what can I do about it' - hence the OP's question.

Answering this with 'they are safe, no need to worry, nothing to see here', particularly without feeling the need to provide evidence, gives me little comfort when there is convincing, detailed studies and information out there to the contrary.

Comfort, however, may well come from questioning, research and understanding - not from trust that is not earned.

Industry/commercial treats LFP's with a great deal more caution than some on here, and have (usually sensitive) experience of when they go wrong.

 

[lustyd]

It’s been discussed many times on this forum. They are far safer than lead acid batteries and you would have to try exceptionally hard to make them unsafe, as demonstrated in the scientific paper claiming they emit hydrogen. The authors created an entirely unrealistic scenario and still ended up with significantly less hydrogen than a lead acid emits just from charging.

Nobody has yet shown a real example of a problem, let alone danger with these batteries in real world usage scenarios. Safety is one of the advantages over lead, not the other way around.