Lithium Battery Box

[CarpeDiem 541]

1 hour ago, bigal.nz said:

So the issue being MNZ want fire proof - the "ANZ" standard doesnt?

The issue is that the cited standard doesn't mention the fire rating requirements of a Li-ion battery enclosure.

Just because it's not mentioned doesn't eliminate common sense.  If you made your battery compartment out of something that burst into flames at 30degC you would still meet the standard but you'd be pretty stupid!

So we therefore turn to other standards that do mention it - e.g., the one which covers the installation of Lithium-ion batteries in RV's and Motorhomes, or the one which covers the installation of Lithium-ion batteries in your house... these standards can be used to provide installers with a baseline that they can work towards.

While the conversation has moved into standards, you originally asked what to build your battery box out of, my recommendation is something not easily combustible. 

 

[Island Time 1,314]

Personally I've NEVER seen a recreational vessel with a fire proof battery box...

With LiFePo4, you are MUCH more likely to have an electrical fire at a high resistance connection or failed appliance than at the battery. Pretty hard to make the entire electrical system fireproof. IMO better to put the main battery switches somewhere easily accessible and/or have remote cut-off switches so you can easily shut down the power source. And decent extinguishers.

I think a LiFePo4 battery fire is EXTEMELY unlikely, especially in a system that meets the standards for monitoring and auto shut off by BMS.

[K4309 428]

How many people have smoke alarms on your boat?

As IT wisely points out, there are many ways to start a fire in an electrical system, not just the battery.

And who has no other portable electronic devices on the boat? No phones, laptops, air-buds, smart watches, vapes, stereo remote controls, party lights, battery banks, handheld VHF's, electric outboards?

I think there is a real risk of fire on a boat, but it isn't from just one source. Consequently it is wise to plan for and assess the risk. Smoke alarm, well placed fire blankets, fire extinguishers, grab bag for a quick get-away. 

Noting that most likely causes of fire are around the main companionway. Engine (under stairs) batteries, switch panel etc, almost always around or adjacent to the main companionway (on a yacht)

Following that, how many people have a second exit point from the saloon? and could everyone onboard actually get out of it (assuming a forward hatch with no steps).

[Frank 185]

Very good observations  from IT and K4309, at the tail end of our 2023 ICR cruise we kept getting brownouts on the Raymarine displays. Long story short we were checking connections when I  nearly burnt my hand on a bus bar . It transpired we had a high resistance connection on DC feed so hot in fact that that it was melting cable insulation in an area that was absolutely  jam packed with wires. Hard to predict a timeline to smoke production  but that was probably the closest I have come to an electrical fire in 40 years of cruising, certainly nothing to do with the battery other than it supplying the smoke. Not wanting to ruffle any feathers but Dr google  reports LiFePO4 batteries are generally considered safer than lead-acid batteries.

[Island Time 1,314]

22 hours ago, CarpeDiem said:

The issue is that the cited standard doesn't mention the fire rating requirements of a Li-ion battery enclosure.

Just because it's not mentioned doesn't eliminate common sense.  If you made your battery compartment out of something that burst into flames at 30degC you would still meet the standard but you'd be pretty stupid!

So we therefore turn to other standards that do mention it - e.g., the one which covers the installation of Lithium-ion batteries in RV's and Motorhomes, or the one which covers the installation of Lithium-ion batteries in your house... these standards can be used to provide installers with a baseline that they can work towards.

While the conversation has moved into standards, you originally asked what to build your battery box out of, my recommendation is something not easily combustible. 

 

Id just like to re-iterate -the issue is that (IMO) Lithium Ion has no place on a yacht. LiFePo4 only!...

[Frank 185]

5 hours ago, K4309 said:

Following that, how many people have a second exit point from the saloon? and could everyone onboard actually get out of it (assuming a forward hatch with no steps)

I think I might have posted this before but when building the  Carpenter 29  I was keen on a soft headliner until reading about a fire in a production yacht in the UK as the owner told it.

There was a fire in the saloon, cause unknown but the skipper was on deck and I think his wife.

Two children were in a quarter berth (screaming) 

Skipper tried to rescue them via the main companion way but was defeated by heat/smoke.

Skipper then went forward to access the saloon via the foredeck hatch but upon entering he found the vinyl headliner was melting generating thick toxic smoke and raining balls of molten plastic.

Skipper eventually smashed his way through the Qtr berth lid from the cockpit with an axe and dragged the kids out. (don't recall where the axe came from) 

Both kids survived but spent a week or so in hospital due to smoke inhalation.

So I stuck with a painted ply headliner and moved the foredeck hatch forward so it was above the Vee Berth, there wasn't a chance in hell of a child exiting the fwd hatch in the factory location, even an adult would have struggled.

 

 

 

 

[Frank 185]

7 minutes ago, Island Time said:

Id just like to re-iterate -the issue is that (IMO) Lithium Ion has no place on a yacht. LiFePo4 only!...

I agree  IT, I used Lithium ION in electric RC models and  albeit rare I witnessed  one or two self-incinerate  at the field (not mine). We have a 320 Ah LiFePo4 in the campervan  It has the Victron internal and external BMS plus fuses, isolation switches, Anderson plug, metal container, external venting   yadda yadda , its probably safer then the FLA in the Carpenter . 

[CarpeDiem 541]

LiFePO4 are Lithium-ion batteries.

What makes a Lithium-Ion battery a Lithium-Ion battery, is that lithium ions move from the cathode to the anode during discharge, and vice versa during charging.

Saying that LiFePO4 is OK, but Lithium-ion is not OK, makes no sense.

Yes, LiFePO4 is a safer chemistry, but it isn't the safest Li-ion chemistry, not by a long shot.

99.99% of LiFePO4 batteries on the market have a liquid electrolyte, this electrolyte is highly flammable and explosive.  If you want to stick with LFP and would like to be an order of magnitude safer, than everyone else, then you need to be looking at Solid State Li-ion batteries.

https://safiery.com/product/safiery-solid-state-lithium-12v-200ah/

 

 

[Frank 185]

10 hours ago, CarpeDiem said:

LiFePO4 are Lithium-ion batteries.

What makes a Lithium-Ion battery a Lithium-Ion battery, is that lithium ions move from the cathode to the anode during discharge, and vice versa during charging.

Saying that LiFePO4 is OK, but Lithium-ion is not OK, makes no sense.

Yes, LiFePO4 is a safer chemistry, but it isn't the safest Li-ion chemistry, not by a long shot.

99.99% of LiFePO4 batteries on the market have a liquid electrolyte, this electrolyte is highly flammable and explosive.  If you want to stick with LFP and would like to be an order of magnitude safer, than everyone else, then you need to be looking at Solid State Li-ion batteries.

https://safiery.com/product/safiery-solid-state-lithium-12v-200ah/

 

 

That's the first solid state battery I have seen that you can actually purchase as opposed to the ones on Youtube that are always "right around the corner" do you know when it became available  ?

[CarpeDiem 541]

2 hours ago, Frank said:

That's the first solid state battery I have seen that you can actually purchase as opposed to the ones on Youtube that are always "right around the corner" do you know when it became available  ?

Late last year. I first saw one installed in a fizz boat in November.

[waikiore 501]

Oh simple me, I go sailing to relax, enjoy the environment and not worry, so that ruled out Lithium batts of any type (and the cost) have I suffered-not a whit.

[aardvarkash10 1,139]

1 hour ago, waikiore said:

Oh simple me, I go sailing to relax, enjoy the environment and not worry, so that ruled out Lithium batts of any type (and the cost) have I suffered-not a whit.

One of the advantages of an extraordinarily low sailing budget is that extraordinarily large problems arising from expensive options are null and void. 

[Island Time 1,314]

22 hours ago, CarpeDiem said:

LiFePO4 are Lithium-ion batteries.

What makes a Lithium-Ion battery a Lithium-Ion battery, is that lithium ions move from the cathode to the anode during discharge, and vice versa during charging.

Saying that LiFePO4 is OK, but Lithium-ion is not OK, makes no sense.

Yes, LiFePO4 is a safer chemistry, but it isn't the safest Li-ion chemistry, not by a long shot.

99.99% of LiFePO4 batteries on the market have a liquid electrolyte, this electrolyte is highly flammable and explosive.  If you want to stick with LFP and would like to be an order of magnitude safer, than everyone else, then you need to be looking at Solid State Li-ion batteries.

https://safiery.com/product/safiery-solid-state-lithium-12v-200ah/

 

 

https://www.anker.com/blogs/others/lifepo4-vs-lithium-ion

LiFePo4 is considerably safer than Lithium-ion... As tested by ABYC.. might see If I can find that report if I have time...

[CarpeDiem 541]

1 hour ago, Island Time said:

https://www.anker.com/blogs/others/lifepo4-vs-lithium-ion

LiFePo4 is considerably safer than Lithium-ion... As tested by ABYC.. might see If I can find that report if I have time...

This is feeling kind of circular... 

LiFePO4 (LFP) is a lithium-ion battery.

It has a cathode material that makes it more stable and less prone to overheating or fire compared to other lithium-ion chemistries, like NMC or NCA.

Misconceptions arise when people treat "lithium-ion" as synonymous with less stable chemistries, like NMC or LCO, which have been linked to high-profile incidents (e.g., smartphone or EV fires).

LiFePO4’s robust safety profile—owing to its lower energy density and higher thermal stability—leads some to mistakenly believe it’s a separate technology. But calling LiFePO4 non-lithium-ion is like saying a stainless steel knife isn’t a knife because it’s more durable than a carbon steel one. The lithium-ion label encompasses a family of chemistries, including LFP, NMC, LCO, and others, all unified by their reliance on lithium-ion movement. 

[Island Time 1,314]

1 hour ago, CarpeDiem said:

This is feeling kind of circular... 

LiFePO4 (LFP) is a lithium-ion battery.

It has a cathode material that makes it more stable and less prone to overheating or fire compared to other lithium-ion chemistries, like NMC or NCA.

Misconceptions arise when people treat "lithium-ion" as synonymous with less stable chemistries, like NMC or LCO, which have been linked to high-profile incidents (e.g., smartphone or EV fires).

LiFePO4’s robust safety profile—owing to its lower energy density and higher thermal stability—leads some to mistakenly believe it’s a separate technology. But calling LiFePO4 non-lithium-ion is like saying a stainless steel knife isn’t a knife because it’s more durable than a carbon steel one. The lithium-ion label encompasses a family of chemistries, including LFP, NMC, LCO, and others, all unified by their reliance on lithium-ion movement. 

Yes, I agree with that, however that's why I put in that link. Other (not LifePo4) lithium ion batts are generally not considered as safe as LiFePo4.  Perhaps this link is better https://www.lithiumbatterytech.com/lifepo4-vs-li-ion-vs-li-po-battery-complete-guide/ and I've quoted some of it below...

Composition of Cathode, Anode, and Electrolyte

The cathode in a LiFePO4 battery is primarily made up of lithium iron phosphate (LiFePO4), which is known for its high thermal stability and safety compared to other materials like cobalt oxide used in traditional lithium-ion batteries. The anode consists of graphite, a common choice due to its ability to intercalate lithium ions efficiently. The electrolyte used in LiFePO4 batteries is typically a non-flammable organic solvent or a polymer gel that allows for the movement of lithium ions without posing significant safety risks.

Unique Features that Distinguish it from Other Lithium-based Batteries

One key feature that sets LiFePO4 batteries apart from other lithium-based batteries is their exceptional thermal stability and safety profile. Unlike conventional lithium-ion batteries that may experience thermal runaway under certain conditions, LiFePO4 cells are much less prone to overheating or fire hazards. Additionally, LiFePO4 batteries exhibit a long cycle life with minimal capacity degradation over repeated charge-discharge cycles, making them ideal for applications requiring durability and reliability.

[Guest 142]

I did a bit of hand wringing before I chose LiFePO4. (Actually  ordered firefly carbon & cancelled as there was a wait)

All that time I've had cordless drills, mini grinders, a laptop and multi phones living onboard with little much of a second thought.

A little strange how we perceive risk. I've used an abused these other chemistries for years, (on land) hence no qualms at all.

 

 

[K4309 428]

43 minutes ago, Guest said:

I did a bit of hand wringing before I chose LiFePO4. (Actually  ordered firefly carbon & cancelled as there was a wait)

All that time I've had cordless drills, mini grinders, a laptop and multi phones living onboard with little much of a second thought.

A little strange how we perceive risk. I've used an abused these other chemistries for years, (on land) hence no qualms at all.

 

 

That is what I'm on about. The vast array of portable lithium type batteries we all have now, and largely forget about.

AIA (or one of the large insurers) report a 17% increase in house fires last year. That is attributed to the greater numbers of portable lithium type batteries in use fairly much everywhere.

Was in Milldale today and noted a brand new very large house that had fresh fire damage. Back of the house was clearly involved, two floors, deck, cladding, smoke damage everywhere I could see. Windows blown out with broken panes still hanging. And no, that wasn't the recent Milldale fire where the fire crews couldn't get their trucks down the streets, that spread to 4 neighbouring properties. Incidentally that one was started by a battery left on a charger.

There are so many things other than your house batteries that can kick off at a moments notice.

[Guest 142]

Nah, won't happen to me. 😇

I:

1. Buy ones that don't do that.

2. My decent  chargers have inherently better safe guards and I'm glass half full type.

3. I always position charger away from combustibles and easily ejectable to  safe open space for exinguishing.

 4. I'm ALWAYS present.

5. I NEVER leave them on the charger indefinitely.

6. I have never used "X" batteries rotating, back to back, with multiple chargers, even when they have got hot.
 

Yeah, RIGHT...

[waikiore 501]

14 hours ago, Guest said:

I did a bit of hand wringing before I chose LiFePO4. (Actually  ordered firefly carbon & cancelled as there was a wait)

All that time I've had cordless drills, mini grinders, a laptop and multi phones living onboard with little much of a second thought.

A little strange how we perceive risk. I've used an abused these other chemistries for years, (on land) hence no qualms at all.

 

 

The big difference to me is that I have seen two Lithium batt fires on boats (in NZ) and the results of one other, however never seen anything from FLA batteries in all the years I have been on the water..... And they are too dear for me

[Guest 142]

51 minutes ago, waikiore said:

The big difference to me is that I have seen two Lithium batt fires on boats (in NZ) and the results of one other, however never seen anything from FLA batteries in all the years I have been on the water..... And they are too dear for me

It would be interesting to know the details,whether it was actually the lithiums that started it, brand of lithium, BMS , configuration for charging, safeguards (or not) in those incidents.

AGMs of similar capacity cost more than my Lithium. That said, you have got to have X amount of geek in you to be comfortable

with the change-over, and could be dependent on what capacity you can currently charge at and whether you have already tweaked it

with configurable external regulated alternator . I already had the perfect setup for DIY LiFePO4 and BMS of my choice.

Horses for courses. If you want completely hands off autonomous system for the electrically impaired,  it is going to cost.