Lithium. Really?

[Bouba]

I don’t really see how it’s any different to people DIY fitting diesel heaters. There are thousands of horrendous installs out there but they rarely cause serious problems.

I’m also unsure how a LFP battery is really any more dangerous than a lead acid battery. The only real safety different is the potential short circuit current but the BMS will deal with that 99.xx percent of the time.

I agree, but the fear of lithium fires is real...even when the reality isn’t

 

[AngusMcDoon]

I don’t really see how it’s any different to people DIY fitting diesel heaters. There are thousands of horrendous installs out there but they rarely cause serious problems.

I’m also unsure how a LFP battery is really any more dangerous than a lead acid battery. The only real safety different is the potential short circuit current but the BMS will deal with that 99.xx percent of the time.

It might not be any more dangerous, but insurance companies don't have enough information to know that yet. They only accept known risks so that the financial wonks can do their calculations. Lead acid batteries and diesel heaters are established tech with known risks. At the moment lithium is an unknown risk, so conditions apply. It looks like things are already changing, and will continue to do so.

 

[Sea Change]

There is probably also another reason....and that is what happens when people start doing DIY work on their electric cars ?.....at the moment it probably isn’t an issue...but eventually people are going to acquire the knowledge...and then what ?...the scale of the claims could be enormous

Most of the DIY stuff I've done on cars has been brakes, hubs, suspension, and bodywork. All of that would be exactly the same on an EV.

Modern IC engines are incredibly complicated and repairing faults is beyond the ability of most DIYers.

 

[Bouba]

Most of the DIY stuff I've done on cars has been brakes, hubs, suspension, and bodywork. All of that would be exactly the same on an EV.

Modern IC engines are incredibly complicated and repairing faults is beyond the ability of most DIYers.

I agree....but there is a new younger generation who may not know how to adjust the points....and yet not be intimidated by the electronics on an EV.

 

[Bouba]

It might not be any more dangerous, but insurance companies don't have enough information to know that yet. They only accept known risks so that the financial wonks can do their calculations. Lead acid batteries and diesel heaters are established tech with known risks. At the moment lithium is an unknown risk, so conditions apply. It looks like things are already changing, and will continue to do so.

Yes, take the burning and sinking of the car delivery vessel....that is generally regarded by everyone (who doesn’t drive an EV) to be caused by lithium batteries.....and a claim that huge must reverberate throughout the entire insurance industry

 

[st599]

I’m also unsure how a LFP battery is really any more dangerous than a lead acid battery. The only real safety different is the potential short circuit current but the BMS will deal with that 99.xx percent of the time.

It's a lot harder to cause an LFP battery to run away, but if they do, they produce hydrogen and toxic gases.

THe circuit design and location of the batteries can mitigate against many.of the issues. But for example, with the current battery location alongside the engine bay on one boat I sail, an engine fire could cause a thermal runaway.

 

[lustyd]

It's a lot harder to cause an LFP battery to run away, but if they do, they produce hydrogen and toxic gases.

THe circuit design and location of the batteries can mitigate against many.of the issues. But for example, with the current battery location alongside the engine bay on one boat I sail, an engine fire could cause a thermal runaway.

They produce far less hydrogen than a lead acid being overcharged and the inly evidence for this is a science paper where they purposefully destroyed the battery in conditions impossible to replicate on any standard installation

Please stop spreading this FUD.

 

[Sea Change]

They produce far less hydrogen than a lead acid being overcharged and the inly evidence for this is a science paper where they purposefully destroyed the battery in conditions impossible to replicate on any standard installation

Please stop spreading this FUD.

IIRC the paper found that LFP only began to outgas hydrogen once the temperature had reached about 300⁰C, by which point the boat itself is likely on fire and with any luck the crew are already in a liferaft.

 

[st599]

IIRC the paper found that LFP only began to outgas hydrogen once the temperature had reached about 300⁰C, by which point the boat itself is likely on fire and with any luck the crew are already in a liferaft.

Indeed, as I said, it would require an engine fire on our boat to hit those temps and would need mitigations in place.

The Underwriter's Laboratory have a good short video course on recommended mitigations for LiFePO4

 

[lustyd]

Indeed, as I said, it would require an engine fire on our boat to hit those temps and would need mitigations in place.

If the engine is on fire, hydrogen offgassing is not a problem since it would never build up to explosive quantities

 

[st599]

If the engine is on fire, hydrogen offgassing is not a problem since it would never build up to explosive quantities

The thermal runaway would however be a problem as the engine room extinguishers wouldn't put it out.

The reasons why Li-ion (including LiFePO4) runaway are known:

1. Over charging
2. Charging when cold
3. Over heating
4. Mechanical damage
5. Short circuit
6. Manufacturing defects

They can be mitigated against in the system design or location and, I personally think, can be made lower than Lead Acid. However, to say they're not an issue is wrong.

 

[Sea Change]

I think it's pretty academic. If there's a big enough engine fire on my boat for the temperature inside the battery compartment to reach 300⁰C, I'm already going to want to be as far as possible from my gas, diesel, and petrol supplies.

 

[lustyd]

Agree, it’s pointless to argue such points. There’s less danger in lfp than lead acid so it’s a no brainer. If any installation, anywhere, ever actually has a problem then maybe let’s circle back to the discussion but right now it simply isn’t a worry any sane person should be thinking about.

 

[billskip]

We are now in the Canaries

if he drives the 3 miles to the wind turbine farm.

That's not you anchored in the bay (Granadilla) down by the wind farm is it ?

 

[geem]

That's not you anchored in the bay (Granadilla) down by the wind farm is it ?

We were there about 3 weeks ago. We are now in Tazacorte, La Palma. We are back to La Gomera tomorrow.

 

[zoidberg]

I kicked off this thread in the hope/expectation that it would draw out - beyond the usual wild-assertions-without-substance - lots of informative observations and knowledge.

Today I'm aware that Yachting World has published an article which should add a little more to the discussion:
YW's take on Lithium onboard

I'd like to have a Lithium batteries installation. I really would. But.... I'm not in the market for buying-in a potentially lethal problem I could not overcome on my own, at sea.

 

[Sea Change]

I'd like to have a Lithium batteries installation. I really would. But.... I'm not in the market for buying-in a potentially lethal problem I could not overcome on my own, at sea.

Arguably the same applies to any energy storage. Gas, petrol, even lead acid.

It's a question of understanding and managing the risks, and deciding whether it's worth it for the benefits.

 

[lustyd]

Doesn’t add anything new as far as I can see. No examples of LFP having an issue and no suggestion LFP isn’t safer than lead.

They had several examples of other lithium chemistries having an issue, and you can tell they need to stir the pot for ad revenue. There’s even an electrical firm who’ve sullied their name for the article, who nobody sane would now engage with.

 

[justanothersailboat]

That article contains so much semi-illogical fearmongery that it makes me want to swap all batteries for li-po out of sheer cussedness (and never mind the insurance). But my use patterns wouldn't benefit, so I probably won't.

The cult of perfect safety really needs to die. Expecting any new tech to be perfectly safe is unreasonable; the old ones aren't either. It just needs to be about the same or not much worse (with other advantages - which are plenty)

 

[lustyd]

It just needs to be about the same or not much worse

LFP is orders of magnitude safer than lead acid. Unfortunately some aren’t able to see that.