While not specifically addressing recreational boats, the Marine Safety Alert issued yesterday by the USCG Marine Safety Center is worth reviewing if you have or are considering adding LiFePO4 batteries. The MSC's focus is and has been on Li Ion batteries on inspected commercial vessels and not on uninspected vessels, however, their guidance is relevant to recreational sailors with LiFePO4 batteries.
CG Guidance on Li Ion Batteries
- Thread starter dlochner
- Start date
I don't understand. They have an example of a boat with LFP batteries that caused a fire because a loosely crimped lug overheated. Then they state that this is a safety hazard "unique to lithium-ion batteries".
No it's not.
And it should be pointed out that the fire was the surrounding cabinetry and battery cases and none of the actual battery chemistries themselves caught fire. The batteries did suffer severe fire damage and did not experience a thermal runaway, which actually shows just how safe they are. Lead batteries in the same situation likely would have exploded and added to the fire.
They do define "lithium-ion" batteries as encompassing a wide range of chemistries (which they list). But their guidelines are determined from the worst case scenarios of the most dangerous chemistry.
LFP is really safe. Really, really safe. I wish ABYC and USCG and others would develop separate guidelines for LFP that relaxed some of recommendations/requirements that were put in place in case more fragile chemistries are used. The constant harping on thermal runaway is one example where guidelines are put in place wrt fire extinguishers and containing structures.
Mark
No it's not.
And it should be pointed out that the fire was the surrounding cabinetry and battery cases and none of the actual battery chemistries themselves caught fire. The batteries did suffer severe fire damage and did not experience a thermal runaway, which actually shows just how safe they are. Lead batteries in the same situation likely would have exploded and added to the fire.
They do define "lithium-ion" batteries as encompassing a wide range of chemistries (which they list). But their guidelines are determined from the worst case scenarios of the most dangerous chemistry.
LFP is really safe. Really, really safe. I wish ABYC and USCG and others would develop separate guidelines for LFP that relaxed some of recommendations/requirements that were put in place in case more fragile chemistries are used. The constant harping on thermal runaway is one example where guidelines are put in place wrt fire extinguishers and containing structures.
Mark
Over the past few years I have been deeply involved in the USCG Inspection process for commercial boats. Two important things I have learned are, all regulations are written in blood and when it comes to safety the USCG Marine Safety Center (MSC) is really conservative.
The Alert was primarily directed to those organizations and individuals who own and operate inspected vessels. LFP is not the usual Li Ion chemistry used in larger vessels and battery powered vessels and thus the more general reference to Li Ion batteries.
The installation requirements for any Li-Ion battery bank in an inspected vessel are rigorous, especially when reviewing the referenced ASTM standard. The concern expressed in the Alert is that Li banks need to be properly installed and maintained and there are inherent safety risks not present with lead acid batteries. And while LFP batteries are not prone to thermal runaway, they do pose their own issues, including the dangers of rapid discharge (shorting) and flammable electrolytes.
For recreational sailors, the message is to not take the installation of Li batteries casually, a trend that seems to be occurring. The marketing of "drop-in" LFP batteries and the frequent claims about their safety I fear are leading to improper or inadequate installations. Recommendations by "professionals" to put LFP batteries in Float or overriding the LFP settings on a charger and use the Power Source mode instead are evidence of this trend.
In the next few weeks we'll be submitting our plans for a LFP bank on an inspected vessel to the MSC for review. It will interesting to see how they respond and what changes or recommendations they will make.
The Alert was primarily directed to those organizations and individuals who own and operate inspected vessels. LFP is not the usual Li Ion chemistry used in larger vessels and battery powered vessels and thus the more general reference to Li Ion batteries.
The installation requirements for any Li-Ion battery bank in an inspected vessel are rigorous, especially when reviewing the referenced ASTM standard. The concern expressed in the Alert is that Li banks need to be properly installed and maintained and there are inherent safety risks not present with lead acid batteries. And while LFP batteries are not prone to thermal runaway, they do pose their own issues, including the dangers of rapid discharge (shorting) and flammable electrolytes.
For recreational sailors, the message is to not take the installation of Li batteries casually, a trend that seems to be occurring. The marketing of "drop-in" LFP batteries and the frequent claims about their safety I fear are leading to improper or inadequate installations. Recommendations by "professionals" to put LFP batteries in Float or overriding the LFP settings on a charger and use the Power Source mode instead are evidence of this trend.
In the next few weeks we'll be submitting our plans for a LFP bank on an inspected vessel to the MSC for review. It will interesting to see how they respond and what changes or recommendations they will make.
Granted. However, I recognize the batteries in the case photo they chose to use, and they are LFP. So I think it was a mistake to use that accident case for the reason they did.
Lead acid batteries certainly have flammable electrolytes. In fact, exploding and flaming electrolyte products is one of the main causes of lead battery fires. And what is produced when they go up in flames is equally as dangerous to be around.
But the real problem with the constant attention to lithium and its continued conflation of chemistries by organizations like ABYC and USCG is that insurance companies and other businesses don't have the deeper understanding of the different chemistries. So they see all of this attention, and make blanket decrees based on it.
Conflating these chemistries has become a dereliction of duty for these organizations. Or at least a sign of pure laziness. It really is a serious problem no different than conflating "batteries"in general. They really need to get more specific when issuing warnings, or guidelines, or even talking about details.
Mark
Yes, it was more of a wiring problem than a battery problem, but not entirely. Let's not be over defensive of LiFePO4. (BTW, I have LiFePO4, so I am not a Li-basher.)
a. It looks like the Li battery did ignite the electrolyte. A good steel case contained the fire. Not bad. However, very, very few of us use steel cases. Our boats would probably have burned down. Anyone on this thread have a steel case? I don't.
b. Was the lug outside of or inside the battery? Not completely clear to me, and that is an important distinction. LA batteries can also have internal shorts, which often lead to overcharging. One of the best reasons to replace a LA battery that is showing its age.
c. LA batteries do NOT have a flammable electrolyte. They can, of course, generate significant hydrogen when overcharging, and a hydrogen gas explosion can rupture the case. But that typically does not cause a fire. Just a really big mess and considerable corrosion. But that is the LA equivalent of thermal runaway, which we agreed is not what we are talking about. Both are very, very rare. You hear more about LA explosion because they are thousands of times more common and have been around for >100 years.
a. It looks like the Li battery did ignite the electrolyte. A good steel case contained the fire. Not bad. However, very, very few of us use steel cases. Our boats would probably have burned down. Anyone on this thread have a steel case? I don't.
b. Was the lug outside of or inside the battery? Not completely clear to me, and that is an important distinction. LA batteries can also have internal shorts, which often lead to overcharging. One of the best reasons to replace a LA battery that is showing its age.
c. LA batteries do NOT have a flammable electrolyte. They can, of course, generate significant hydrogen when overcharging, and a hydrogen gas explosion can rupture the case. But that typically does not cause a fire. Just a really big mess and considerable corrosion. But that is the LA equivalent of thermal runaway, which we agreed is not what we are talking about. Both are very, very rare. You hear more about LA explosion because they are thousands of times more common and have been around for >100 years.
Yeah, I share your frustration, Mark. People who really should know better make blanket statements about "lithium batteries" that really only apply to lithium-ion batteries. The differences are so significant that they really need to be discussed completely separately. They have very few performance or risk characteristics in common.
It doesn't help that, for some reason, car manufacturers continue to use Li-Ion and the hazards associated with that chemistry are dramatic and increasingly well-known. So, people just assume that those hazards are inherent to all lithium batteries.
Lumping all of these together under “lithium” is like issuing fuel storage warnings and failing to distinguish between gasoline and diesel.
It doesn't help that, for some reason, car manufacturers continue to use Li-Ion and the hazards associated with that chemistry are dramatic and increasingly well-known. So, people just assume that those hazards are inherent to all lithium batteries.
Lumping all of these together under “lithium” is like issuing fuel storage warnings and failing to distinguish between gasoline and diesel.
Is this the old style electrolyte :
H2SO4 + H2O
............ in batteries of old or something new which I need to get into to give me additional sleepless nights
?I took a bit of liberty and a short cut by saying LA electrolyte was flammable, but the fact remains it produces a highly flammable gas, and fires and explosions caused by it are common. Any spills on organic material (oil) or metals can cause them to catch fire or release hydrogen gas that catches fire. So in this sense, it really is a fire hazard. It is also dangerous by itself to be around when liberated.
Lithium electrolyte does not cause a fire either. It just has the potential to burn when lit. Unlike LA, spilling it doesn't cause other materials to catch fire or liberate an explosive gas. To put the LFP electrolyte fire risk in perspective, a LFP battery only contains 80-100ml of electrolyte with a flash point of 150C. Note that the diesel everyone carries around has a flash point about half of that, and we won't even discuss gasoline or propane.
You don't just hear more about LA explosion and fires compared to LFP because they are more common batteries and have been around a long time. It is the other side of that ratio - you don't hear about LFP fires simply because they are exceedingly rare.
Every stored energy source needs to be properly handled and installed, whether that means liquid fuel or a spinning flywheel or an electric battery. In every example, one can go over-the-top and over-think the risk vs the solution equation. Your diesel would be safer if stored in an underground tank 500' away from your boat, but the real-world risk/solution ratio doesn't suggest its necessity. Yes, a fully-enclosed metal container is safer for all batteries, but real-world experience doesn't suggest it is necessary for LFP. One could make a good case it is necessary for LA, though.
My complaint here is that ABYC, USCG, etc not distinguishing LFP from other lithium chemistries, and treating them all the same, is similar to if they didn't distinguish among all stored fuels, and treated them all the same.
BTW, there are many LFP batteries that do come in steel cases, and most LFP cells themselves made today (and comprise the insides of most batteries) have aluminum cases.
Mark
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Obviously, I knew you knew
.Speaking of lithium batteries (ion or whatever have you) brings us to EVs. And you may not want to own an EV here in British Columbia (BC) if you live on one of our coastal islands. All of the coastal islands here are served by our provincial government BC Ferries and they recently had an EV catch fire on one of their ships and of course it was a bitch to extinguish.
With that little excursion under their belt, they have now excluded from boarding their ferries, any EV that is not in pristine condition. The island dwellers own a very high % of the EV's in BC because they are tree huggers and rather wealthy to boot. The outcome now is that if you have an EV and it craps out on a BC island without a high tech auto service shop (and none of them do), it's pretty much scrap metal as the cost of barging it to a repair facility is prohibitive.
BC Ferries does have select days for moving explosives, liquified petroleum gasses, gasoline, and every other dangerous goods imaginable, but no damaged EVs.
It was a good idea while it lasted but hit a few snags along the way. BC produces 80% of its power from hydroelectric dams so its a perfect match for EVs. Unless you live on an island.
Transport Canada change forces BC Ferries to prohibit damaged EVs
BC Ferries is now prohibiting many electric vehicles from sailing on board its vessels due to a Transport Canada regulation preventing damaged vehicles from being transported.
cheknews.ca
Talk about thread drift
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How do they determine that? Particularly since the condition of the exterior or interior has little relationship to the condition of the battery system. A pristine new EV could have run over something and dented/punctured the battery, or knocked a wire into a short circuit, on the way from the dealership to the ferry.
A better idea might be to let non-EV's on first, then put down a gate connected to a hydraulic ram, then load the EV's. If an EV catches fire, the ram pushes the gate and all the EV's dump off the ferry into the water.
Mark