The Dangers of Lipo Batteries

[sailingharry]

Originally Posted by rslifkin

That's one way to solve that concern. But it's still good to know what happens, as some boats end up mounting the batteries fairly low in the boat due to available space or other factors. And knowing what happens if you get them wet and salty would determine whether it's necessary to find a higher mounting location or not.

Yep. In my boat, the tops of the batteries are maybe 18-24 in above the bottom of the hull. And outboard on the port side, so if heeling to port, I could easily have them underwater long before sinking. Of course, if water is that deep and I have now submerged my power source, I'm probably not going to be floating much longer!

[sailingharry]

Originally Posted by s/v Jedi

Those are not professionals. I can even buy properly crimped cables on Amazon, even with different lugs on each end to accommodate the different size studs.



I paid $150 for the FTZ crimp tool.

It is why I put it in quotes. They are people engaged in marine service. Those that do maintenance by hiring people in the business think they are getting good work, but often are just unaware of what they are getting!

[s/v Jedi]

Originally Posted by sailingharry

It is why I put it in quotes. They are people engaged in marine service. Those that do maintenance by hiring people in the business think they are getting good work, but often are just unaware of what they are getting!

Yes, this is why I do everything myself. It’s like a restaurant where the food isn’t as good as when you make that dish yourself

[dannc]

Regarding fire suppression in LiFePO4 batteries, the Victron LiFePO4 MSDS(Material Safety Data Sheet), https://www.victronenergy.com/upload...tteries-EN.pdf, states,

SECTION 5 - FIREFIGHTING MEASURES
Extinguishing media: dry chemical, CO2, water spray or regular foam. Large Fires - Water spray fog or regular foam

Later,
Dan

[BlueH2Obound]

MP;
Your post is giving very conflicting information. You state you are talking about LiFePO4 batteries as currently used in most boat battery banks. Your video identifies the battery in question as a LiFePO4 battery (just to clarify, that means Lithium Iron Phosphate). Then in your own post, the battery that catches fire is stated as being

"The combustion behavior of 50 Ah LiFePO4/graphite battery"!
It's either LiFePO4, (Lithium Iron Phosphate), as used is boats, or one using graphite, more commonly used in electric cars. . . . It can't be both! So you post is really meaningless unless it is clarified.

Originally Posted by Melbourne Park

There are several ways that studies discuss potential for thermal runaways of LFP batteries. Just because a lab uses one type of method to ignite LFP batteries, does not mean their results have no meaning. They could use dozens of ways to get LFP cells to a critical temperature.

Obviously consideration of placement of LFP and the potential for things going wrong is worthwhile. Counter to that view is - "LFP cannot burn, its perfectly safe, I can put it anywhere I like."

It seems to me that the critical temperature is from 124 C to 128 C (degrees).

It seems too, that the higher the state of charge, the higher the temperature of the thermal runaway.

Now, many advertisements I have read, say that the LFP cannot burn, and that for instance, they require 500 C to burn, so they are completely safe. My view is those advertisements are false.

Mistreat electronics and one may pay a price.

And stupid behaviour with LFP might cause issues.

[Wotname]

Originally Posted by jcapo

What happens when batteries that are considered safe for boats, lead acid based, are punctured with a giant steel spike?

One of the reasons why the AGM lead acid battery was invented.

[wholybee]

If I had the time and money, I would buy a handful of FLA and AGM batteries, over charge them, then subject them to a direct short, and drive a spear through the shorted battery. And film it for YouTube.

I honestly don't know what would happen, but I have to imagine it would be very bad.

[rslifkin]

Originally Posted by wholybee

If I had the time and money, I would buy a handful of FLA and AGM batteries, over charge them, then subject them to a direct short, and drive a spear through the shorted battery. And film it for YouTube.

I honestly don't know what would happen, but I have to imagine it would be very bad.

It would be an interesting test to see what the differences are in behavior between LFP and the stuff we're already used to dealing with in situations like that.

[Bellinghamster]

For those who keep ranting about dangers of AGM, here's a bit of my experience:
I ran a seismic and environmental test lab for over 10 years a company that sold ~ $60M USD worth of AGM batteries per year to the telecom and CATV industry. I've done a LOT of battery testing and never experienced an AGM battery failure except in extreme overcharge conditions.
I used the same set of batteries for probably 100 earthquake tests of different enclosures and racks, plus lots of swept sine (resonant search), many hours of low-level vibration, truck and rail shipping vibration simulations. (note: These were C&D TEL12-180F batteries).
One time I was running earthquake test on a 7ft tall rack of telecom batteries (~3500lbs of batteries!), the rack hit resonance and 3 of the 140lb batteries launched out of the top shelf, dropping >7ft onto the concrete floor and the edge of my shaker table = The cases cracked, a bit of AGM "stuffing" came out, but no liquid mess and none of the batteries heated up or smoked.

I drop tested group 27 and Group 29 AGM batteries - 6ft vertical drops onto concrete on all 6 faces and 3 edges. Other than punching the terminals into the top the batteries stayed intact - no smoke, no heat, no spillage.

(if people are interested I might be able to dig up some pics/videos)

The battery failures I did witness or hear of were a couple times when someone accidentally charged a 12V battery or 24v string with a charger set for 36 or 48v. That'll let the smoke out, swell the cases and stink up the building!

[s/v Jedi]

Originally Posted by Bellinghamster

For those who keep ranting about dangers of AGM, here's a bit of my experience:
I ran a seismic and environmental test lab for over 10 years a company that sold ~ $60M USD worth of AGM batteries per year to the telecom and CATV industry. I've done a LOT of battery testing and never experienced an AGM battery failure except in extreme overcharge conditions.
I used the same set of batteries for probably 100 earthquake tests of different enclosures and racks, plus lots of swept sine (resonant search), many hours of low-level vibration, truck and rail shipping vibration simulations. (note: These were C&D TEL12-180F batteries).
One time I was running earthquake test on a 7ft tall rack of telecom batteries (~3500lbs of batteries!), the rack hit resonance and 3 of the 140lb batteries launched out of the top shelf, dropping >7ft onto the concrete floor and the edge of my shaker table = The cases cracked, a bit of AGM "stuffing" came out, but no liquid mess and none of the batteries heated up or smoked.

I drop tested group 27 and Group 29 AGM batteries - 6ft vertical drops onto concrete on all 6 faces and 3 edges. Other than punching the terminals into the top the batteries stayed intact - no smoke, no heat, no spillage.

(if people are interested I might be able to dig up some pics/videos)

The battery failures I did witness or hear of were a couple times when someone accidentally charged a 12V battery or 24v string with a charger set for 36 or 48v. That'll let the smoke out, swell the cases and stink up the building!

Please define “extreme overcharge”. Like the test done in the laboratory, did you use 10x the regular charge voltage, i.e. 140V instead of 14V? Because that was what was needed to make the LFP cell fail.

Also, did you puncture them with a big metal spear like in the other video, creating internal shorts, then do it again and again to introduce sparks for combustion? This is what was needed to make the LFP cell fail.

I had LA batteries explode right under me… flooded ones unfortunately. It wasn’t pleasant.

[Melbourne Park]

Originally Posted by BlueH2Obound

MP;
Your post is giving very conflicting information. You state you are talking about LiFePO4 batteries as currently used in most boat battery banks. Your video identifies the battery in question as a LiFePO4 battery (just to clarify, that means Lithium Iron Phosphate). Then in your own post, the battery that catches fire is stated as being

"The combustion behavior of 50 Ah LiFePO4/graphite battery"!
It's either LiFePO4, (Lithium Iron Phosphate), as used is boats, or one using graphite, more commonly used in electric cars. . . . It can't be both! So you post is really meaningless unless it is clarified.

It refers to both. It was a quote. The reference assumes some knowledge, An LFP battery refers to the cathode. The anode is typically graphite.

[Melbourne Park]

Originally Posted by s/v Jedi

Please define “extreme overcharge”. Like the test done in the laboratory, did you use 10x the regular charge voltage, i.e. 140V instead of 14V? Because that was what was needed to make the LFP cell fail.

Also, did you puncture them with a big metal spear like in the other video, creating internal shorts, then do it again and again to introduce sparks for combustion? This is what was needed to make the LFP cell fail.

I had LA batteries explode right under me… flooded ones unfortunately. It wasn’t pleasant.

I jump started two Jaguar cars in 1976. One was a Mark II, the other a 420 G. The engines bays were filthy, and I did not clean the battery terminals, because I was wearing a suit, and a costly (for me) Burberry overcoat. After connecting the earth (following the negative to the chassis attachments) on both batteries, I then connected the positive bridge cable. Shortly after the acid boiled, the battery had a small hydrogen explosion, and spattered hydrochloric acid on my tie, my coat, but it did miss my eyes.

So - who cares about batteries. I discovered that the Mark II Jag had a positive earth. And the 420G Jag, used a conventional negative earth. Thanks Lucas.

Weirdly, I drive a Land Rover for towing. And it shares a lot of its tech with Jag. I never thought I'd go back ...

Incidentally, boats typically have plastic cases with lids for lead acid batteries. My Jeanneau has them. And the Jeanneau specifies only AGM variants of batteries. I asked the electrical guys - why the plastic cases in the boat? They said for wet batteries ....

Lots of things make me wonder.

For my boat though, its designed to sail at 22 degrees (twin rudder). The batteries are close to the water line. Its a shallow boat. I can easily imagine with hitting something and water coming in, or recovering from turning turtle, that water would get into my battery compartment.

And thinking about battery compartments - they all - including LFP - stress air circulation - due to air aiding cooling. And when there is air circulation, there will be the potential for water access.

As far as mounting batteries high - they would then be low if upside down!

[sailorboy1]

Originally Posted by wholybee

If I had the time and money, I would buy a handful of FLA and AGM batteries, over charge them, then subject them to a direct short, and drive a spear through the shorted battery. And film it for YouTube.

I honestly don't know what would happen, but I have to imagine it would be very bad.

you would need to repeat the experiment a few times and include both wooden and silver spikes, daylight and full moon

[rslifkin]

Originally Posted by s/v Jedi

I had LA batteries explode right under me… flooded ones unfortunately. It wasn’t pleasant.

Flooded battery explosions are certainly a nasty thing. I think any of the alternative options (gel, AGM, LFP) all pretty much eliminate the risk of a corrosive liquid electrolyte spill or an internal explosion like FLA can experience.

[Melbourne Park]

The reality is there are lots of warnings about LFP batteries, including from the small print provided by the manufacturers. As there are for as an example, AGM batteries.

There are also many variables in the construction quality of LFP batteries. Which IMO is the most important issue, as soon as we can accept that LFP provides a much safer lithium "architecture" than any other available lithium battery.

I recall Will Prowse saying that while LFP batteries can "burn", their flammability resembles something like wood. The key difference with LFP from other available lithium as far as safety is concerned, is that LFP doesn't produce oxygen when something causes the battery to overheat, unlike other Lithium batteries. Of course, if one can add oxcygen to an overheated LFP battery, then combustion can occur, and much of that depends on other flammable materials potentially used in the battery's construction.

Another benefit of LFP compared to other lithium batteries, is that when it is in an overheated state, its gas production takes a long time, unlike other lithium batteries. While the gases are not good, and can react with water, the length of time for an LFP battery to produce gas is something like 20 times slower than other available lithium batteries.

So IMO, compared to lead acid batteries, LFP offers longer life, storage volume savings, lighter weight and a competitive price point. LFP installations into boats previously setup for lead acid batteries, will also will require various electrical system changes to avoid other issues occurring in a boat.

For a rough water boat, IMO AGM batteries seem the most sensible form of lead acid battery. The AGM is quite primitive, does not rely on internal electronics, but of course, its quality of manufacture does also vary a lot. In comparison, LFP requires internal electronic safety systems to avoid failure: which IMO makes the choice of which LFP brand of battery one chooses, being a more critical choice for LFP for boats, than when one chooses an AGM battery.