Danger of saltwater flooding of lithium batteries

[rgano]

Just watched a video about 85 house fires attributed to "lithium batteries" after a surge of seawater flooded a community. 17 were vehicle fires while the rest were from other small and large devices powered by lithium batteries.

Question: Are the big lithium battery banks populated with batteries equipped with BMS susceptable to creating fires when submerged in saltwater, or does the BMS do an effective job of shutting them down?

 

[rslifkin]

LFP batteries with a BMS are probably a lower risk than a lead acid battery flooded by seawater.

 

[DDW]

Electronics of any kind are not known to work well in salt water. You can safely assume the BMS will "not perform as intended".

There is at least one data point, the Volvo 70 that ended up on the reef in the Indian Ocean (because they didn't zoom their vector charts enough). The boat flooded, the Mastervolt LFP batteries started to smoke and steam and they took them out and submerged them on the reef they hit. Didn't catch fire though.

 

[ksanders]

if my house batteries get submerged, the boat is already lost.

If they catch on fire so be it.

 

[SteveK]

Rich, you should share the link so our opinions can be formed on what you saw.
P.S. I agree with Kevin, if the LFP get wet all is already lost.

 

[tiltrider1]

There are certain Lithium chemistries that have an extreme negative reaction to salt water. LiFePo4, known in the boating world as LFP is not one of those chemistries. In fact LFP batteries have never been known to catch on fire.

It doesn't take much research to realize this. I don't know why people insist on believing all batteries are the same. Maybe it goes back to those who report. The minute some one says Lithium ion battery, I know they don't really know what they are talking about. If they did they would report the true chemistry. My guess is all those fires were NCA batteries not LFP.

 

[Delta Riverat]

If mine get wet they will only be wet on the outside, ie completely sealed. Unless the ABS case got cracked, no entrance possible. And yeah if the batteries are submerged and the cases are cracked I have way bigger problems than wet batteries.

 

[Comodave]

Just watched a video about 85 house fires attributed to "lithium batteries" after a surge of seawater flooded a community. 17 were vehicle fires while the rest were from other small and large devices powered by lithium batteries.

Question: Are the big lithium battery banks populated with batteries equipped with BMS susceptable to creating fires when submerged in saltwater, or does the BMS do an effective job of shutting them down?

Just a quick search about lithium batteries in cars says they mostly use lithium ion type batteries. Some manufacturers use slightly different types of lithium ion batteries. I am certainly not an expert on electric cars and have done zero research except to google this question.

 

[Andiamo2018]

Thank you for doing that little bit of research Comodave!

 

[HeadedToTexas]

If your LFP bank is flooded, you either chose a very poor site for the bank or your boat is sinking and you have far bigger problems than battery failure. At that point, might a fire be preferable to the environmental impact and salvage job ahead?

 

[Comodave]

I put LiFePO4 batteries in our last boat. I mounted them in a salon cabinet. I didn’t want them in the engine room due to the heat.

 

[rgano]

I am sorry about not having a link for the info in my first post because I was watching a North Carolina fire chief on TV talking about what his department saw in Hurricane Helen.

If your Li batteries are high in the vessel, I expect that the vessel is lost if they are under the wawa, but many battery installations, quite possibly replacement lithiums included, are low in the vessel leaving plenty of reserve buoyancy to work with in saving the vessel if water is over them. So circular argument says mount them high and be ready to use them to pump out .

 

[Don L]

I don't see why the risk of flooding your LFP are really any different than flooding any batteries. If anything maybe the BMS will shutdown the LFP before they just short out. Meanwhile if you short out acid batteries they explode.

Meanwhile your boat is sinking and power is out. Focus on what to do in that case.

 

[rgano]

Precisely, battery power is not necessarily going to save the day. There are lots of other things to do like fothering the hull - got tarp?

 

[SteveK]

My batteries require at least 18 inches of water to be in danger. IF that occurs then the bilge pumps have already failed.

 

[dannc]

LFP batteries are not supposed to be able to catch fire but they can outgas nasty chemicals. One of those chemicals is hydrogen. There are two videos out there of a UK canal boat where the LFP batteries outgassed. It appears the gas made it's way from the battery compartment into the rest of the boat where a spark was found causing an explosion destroying the vessel.

One of videos showed water in the battery compartment but it is not clear what caused the out gassing.

 

[Frosty]

LFP batteries are not supposed to be able to catch fire but they can outgas nasty chemicals. One of those chemicals is hydrogen.

Interesting. So I guess like good ol' lead acid in that way.

 

[dannc]

Interesting. So I guess like good ol' lead acid in that way.

Yes, from a H perspective. Though, I don't think lead acid will produce other nasty chemicals like LFP does.

People seem to think that LFP batteries are "safe," and they are, but the gas they can produce is a concern. The commercial LFP batteries I have looking into have racks that can handle the outgassing if it occurs and have a mechanism to prevent thermal runaway from cell to cell.

 

[Delta Riverat]

I didn't think LFP chemistry was prone to thermal runaway.

 

[SeaGator]

I didn't think LFP chemistry was prone to thermal runaway.

Yes, they very much are. But the chance is about the same as being struck by lightning and way less than being killed by walking at night in a big city.

 

[Frosty]

Well "prone" means "likely" or "has a tendency to." Like say paper is prone to disintegrate when it gets soaking wet.

So if the chance is the same as being struck by lightning I would categorize it as possible but rare. Which would not be prone and definitely not very much prone.

Now I'm wondering which it is....?

 

[Delta Riverat]

Me thinks struck by lightning is a better chance than LiFePO4 thermal runaway.

 

[dannc]

The manual for the batteries is interesting regarding the PPS(Propagation Prevention System) and thermal runaway.

The *** is used to highlight text.

RS230 is the name of the battery.

6.3.6 PPS connection
The PPS connection is an optional system used to fill the battery with a PPS fluid to prevent thermal runaway propagation *** in case of a single cell thermal runaway event.*** The connection type is the same as for the fluid thermal management connections in chapter 6.3.4.

See the MG RS PPS Tank manual for detailed information about the pressurized tank.
NOTICE:
The PPS system is an optional system. *** Due to the LFP chemistry of the cells, the RS230 has no thermal runaway propagation between cells as tested according to the IEC-EN62619 test 7.3.3 – Propagation test ***

Notice they are starting that a thermal runaway can happen in a single cell and thermal runaway can't spread to another cell. According to the test.

So the obvious question, for which I have no answer is, how much gas would be produced from a one cell thermal runaway event?

Question two is how is a thermal runaway prevented from spreading to another cell? Don't have the answer to that either.

The RS230 battery and rack has duct work to evacuate any off gassing that happens as well as the plumbing for the optional PPS system

 

[dannc]

Me thinks struck by lightning is a better chance than LiFePO4 thermal runaway.

My dads boat was hit by lightning but it caused very little damage. Having said that, it was little damage because boats back then did not have much to damage. He lost his lights, depth sounder, VHF, and anemometer. So everything on the boat that was electrical was fried. What would that do a LFP battery?

I have seen lightning hit within a 100 yards of me both on land and water several times. Too many times to be honest. Once was enough. I have seen bolts hitting the ground as if Zeus was trying his best to hit me. Dozens of strikes Thankfully, I was in a car, driving like heck and did not get hit. Impressive it was though.

Lightning scares the heck out of me on a boat. Lots of boats are hit by lightning, so while the chance of a LFP runaway might be low, the consequences could be severe. The videos out there of the canal boat are instructive. The boat was destroyed. Thankfully, nobody was onboard. Having that happen offshore....

 

[slowgoesit]

Interesting. So I guess like good ol' lead acid in that way.

Yep, and those lead acid batteries, which, being so heavy are generally mounted low in the hull for stability reasons, thus closer to the bilge, when flooded with sea water emit toxic chlorine gas . . . which will quickly incapacitate any individual attempting repairs . . . . . . but FLA are safer than LiFePO4 . . .

 

[Coconut Runner]

Just watched a video about 85 house fires attributed to "lithium batteries" after a surge of seawater flooded a community. 17 were vehicle fires while the rest were from other small and large devices powered by lithium batteries.

Question: Are the big lithium battery banks populated with batteries equipped with BMS susceptable to creating fires when submerged in saltwater, or does the BMS do an effective job of shutting them down?

Lithium and water do not mix,,,,,,,,,water causes fires among lithium-ion batteries and burns at 2200 degrees.

 

[tiltrider1]

Lithium and water do not mix,,,,,,,,,water causes fires among lithium-ion batteries and burns at 2200 degrees.

This is a fear mongering statement. Some Lithium chemistries do not mix will with sea water. LFP is not one of those chemistries. In fact there is no record of LFP catching on fire. No one is currently recommending the use of any Lithium chemistry other than LFP.

I question the motives of this post.

 

[tiltrider1]

My dads boat was hit by lightning but it caused very little damage. Having said that, it was little damage because boats back then did not have much to damage. He lost his lights, depth sounder, VHF, and anemometer. So everything on the boat that was electrical was fried. What would that do a LFP battery?

I have seen lightning hit within a 100 yards of me both on land and water several times. Too many times to be honest. Once was enough. I have seen bolts hitting the ground as if Zeus was trying his best to hit me. Dozens of strikes Thankfully, I was in a car, driving like heck and did not get hit. Impressive it was though.

Lightning scares the heck out of me on a boat. Lots of boats are hit by lightning, so while the chance of a LFP runaway might be low, the consequences could be severe. The videos out there of the canal boat are instructive. The boat was destroyed. Thankfully, nobody was onboard. Having that happen offshore....

You keep referencing the explosion on the canal boat and suggesting it was caused by the LFP batteries off gassing. However, there is no evidence that was in fact the cause of the explosion. In fact, there is evidence that the batteries were not the cause of the explosion.

Why the continued fear mongering? What is your motive for pushing an unproven narrative?

 

[SteveK]

This is a fear mongering statement. Some Lithium chemistries do not mix will with sea water. LFP is not one of those chemistries. In fact there is no record of LFP catching on fire. No one is currently recommending the use of any Lithium chemistry other than LFP.

I question the motives of this post.

DITTO, I wish lithium ion generality would not be brought up when most everyone should know LFP on boats is a safer breed of lithium ion.

 

[Frosty]

Just as a side note, I have seen a lead-acid house bank in a boat actually start on fire when the boat was struck by lightning (in addition to other damage, such as holes where it left via the running gear).

So a lightning strike if you have a lead acid house bank could cause a battery fire and holes through the hull. I'd have to think said battery fire would send some unpleasant gasses into the (sinking) boat.

So this has always been a potential problem. Or is there a marked difference if you have LFP batteries? (Not some other chemistry of "lithium" batteries.)

Otherwise I'm just thinking that electrical systems, and hulls that require continuity to float are in general at risk during a lightning strike. Which would not be anything new.

(If there is new/different information, then of course we want to know about it.)