The detail of this comment might make interesting analysis, but perhaps a rabbit hole for another time.
Prejudgement rarely provokes a healthy nursery for new information. No surprises there.
In your experience. Not mine.
OP asked about fire control for LFP, not how it compares with LA.
I think instead of considering the batteries the source of the fire perhaps the solution should be to protect the lithium batteries from a fire originating elsewhere .
It would be better to fit one auto extinguisher with suffucient capacity for the space.
They literally said it in the paper. Did you read it?
Please provide details. This has been discussed many times on the forum and no examples have ever been provided.
Do not do this. You should only have a single auto extinguisher in the engine space. With two small ones a fire could start and set one off, which isn't big enough to extinguish it, the fire then spreads and sets the other one off, which also isn't big enough to extinguish it. One bigger extinguisher will give it everything it's got.
It depends on what criteria you use. If H2 gas release and potential for explosion is your concern then LA are clearly worse. If direct substitution* for a system designed for LA is your priority then LA are probably better.
I’m struggling to think of a criteria by which they’re less safe?
In a correctly specified and installed LFP system the BMS will provide protection for many things, including (but not limited to):
Care to share what your experience of LFP problems are ?
It's obvious that an incorrectly installed LFP system might be less safe than a correctly installed LA system, but it's far from a reasonable argument against LFP.
I think what's obvious to you may not actually be obvious to the average DIY'er about to replace their batteries who reads some vague marketing material about new lighter, higher capacity "LA replacement" batteries. Since most insurers don't prohibit Li entirely but just want an installation they can trust it seems this is actually the concern. Obviously there are some people who are just convinced that Li ions are a death sentence, ironically some Li advocates have similar repulsion to gas cookers, probably not grounded in a rational risk assessment - but that is to some extent human nature and internet fora tend to polarise opinion rather than reaching common ground.
Really - in the context I described?
It isn't.
The BMS is a failsafe and should not be used to regulate charge etc. Even if you tried to, you cannot reliably get it to control alternator charge and temp's.
He's right, it's virtually guaranteed to destroy your alternator, if it's a standard one.
I've been here a lot longer than people have been wanting LFP on their boats and i do a lot of other things too.
How about if the idiot drill a hole in a gas pipe then uses a blowtorch for leak detection ? Or drill a hole in his petrol tank while he's smoking a cigar ?
The BMS is a last ditch safety device, in addition to failing you would need faults with additional equipment.
Right so we seem to be in agreement that amatuer people blindly following instructions from a supplier claiming to offer a drop in solution could at the very least damage your other kit.
Of course - but Lusty wanted examples of situations where LFPs *could* be riskier than LAs. The issues of hydrogen from LA's has been widely reported for decades but people still occasionally manage to fall foul of them, whilst others persist in saying it almost never happens, or it won't happen if people just use their brain.
There's video footage on youtube of an LFP cell having a big spike put through it and then emitting huge quantities of fumes, glowing red inside and then catching fire.
Not sure I understand the analogy. The immediate consequences of a punctured lifejacket are 100% known, it would make a dull video. I've not seen any LFP damaged whilst insitue in a typical installation - only in an isolated cell in an open field. If the single cell fumes a lot and gets really hot does it get hot enough to damage its neighbours? Does it or the hot can trying to get our of it damage a typical enclosure or effectively "explode" our of an enclosed box? If it doesn't then it would be a great "LFPs are safe" video.
Because they are.
I don’t think I agree, even with none of the safety features they’re very safe as a chemistry. Obviously nobody sensible would install without but under/overcharging will just harm the battery rather than be dangerous (unlike lead). Short circuit is about the same danger wise.