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Comment by tiahura | Hacker News Reader

Bologna aside, isn’t there a legit issue re the difficulty in extinguishing an EV battery pack?

I can see how “just give it a few days to burn itself out isn’t a viable strategy on a boat.

Hm, it's not that difficult in the end, at least on land.

First part is checking whether the battery pack is affected after all. Not all EV car fires lead to problems with the battery pack and sometimes you can just extinguish the fire like any other.

We check the battery by inspecting it with thermal cameras (remove any protection on the bottom of the car first - not easy). If the temperature of the pack rises after the initial fire has been put out, the battery pack seems to have a problem.

In that case, permanent cooling is the way to go. You will start doing this by sprinkling the battery with a hose to keep temperatures stable. At some point, you'll want to release the personell and need a more permanent solution.

That's where troughs come in to play. You will fill that up with water until you can completely submerge the battery pack in water. Either place the car in first or lift it in afterwards, that doesn't matter, it's just a handling thing. The car stays in there for several days until the chain reaction in the battery has stopped.

I can see how this might be somewhat more complicated on a ship in the middle of nowhere, but you wouldn't want to have a burnt-out non-EV car standing on your ship for an extended period of time, too. So you'll have to reach shore quickly anyway and get more help.

Seems like a crane and dropping the car into the ocean is the solution then! /s

If all else fails, I'd consider that option.

But the problem seems to be more of how to get a burning car out of the pile of cars in your ferry. Doesn't matter if EV or not, you want to have it out of there at some point and that seems to be tricky.

How well can you manage the temperature of a "burning" lithium car battery with unlimited water supplies? Can you easily keep it cool enough to not damage the floor or deck of the boat it is on? If you can, it seems like the long term solution would be two seawater pumps, hoses, and a barrier so you can erect an impromptu kiddy pool around the burning vehicle, and just flow constant seawater around it until you get to port or it stops being a problem.

That could indeed be a solution. Enough mass of water or enough flow of water will transfer the heat away fast enough.

The battery is done at that point anyway, but submerging it will stop flames and toxic fumes from forming from an "open" fire. The cells will "melt" and react with each other on and on until they're done, you can't really stop that.

The same thing is done with gas bottles. Once they have been subject to flames or enough heat, they are considered unsafe and will have reactions going on in the inside. You can measure those due to a rise in temperature on the outside, too.

Gas bottles are also put into containers full of water, for at least 24 hours, until the reactions on the inside are done.

Cooling them prevents them from heating up until they burst though. Same goes for EV battery packs.

Trapdoors, under each car. Put the captain in a big twirly seat and give him a red button and a white cat, because everything's better when you're cosplaying as a Bond villain.

(Ok, serious question about the portable-barrier-and-pump solution: could there be any chemical risk from using sea water, rather than fresh water?)

I was just at the fire station in Netherlands last week for a tour and asked the very question.

Answer: Electric cars are different from ICE cars in that the fire must be put off differently. We are trained to handle an EV fire by using a “blanket” method wherein a boxy containment zone will be erected to completely enclose the burning EV limiting ability of that chemical reaction to break out in a larger way. We have the tools, and the necessary practice for it, and treat it no different than a regular petrol car.

Sure, but that doesn't work on a ship. Or in an enclosed parking garage on land.

I think this post was made because of this: https://www.bbc.co.uk/news/world-europe-66310280

From the article:

>Last year a cargo ship carrying 4,000 luxury cars caught fire and sank off the Azores. Lithium-ion batteries in the cars caught fire and firefighters needed specialist equipment to put out the fire.

There is a cargo ship right now in the NL that apparently has ~3,000 cars on it - and its on fire. I wonder if it has many EVs on it.

Ah 25 Evs on it...

https://www.reuters.com/world/europe/one-dead-cargo-ship-fir...

A small contingent of about 25 EVs take responsibility for the operation, destroying thousands of their ICE foes.

And the fact that the fire "started near the EVs" is a False Frag.

Since it's a ferry, a solution could be to just push if overboard. How often do fires on ferry happen?

you can't push them when they are deep in a pack of cars

You would have to push the entire column of cars before it overboard.

So make sure the electric cars are loaded last.

Probably still cheaper even paying for the recovery effort if they are not dumped too deep to replace those cars than to replace the ship, in terms of total cost if the ship is totalled.

How you push a column of cars around a raging fire is another problem. I don't know what I'd do.

These are not open-deck ferries, the cars are in closed decks.

So it's easy to cut off the oxygen supply to the fire?

Sure - so long as you've spent the necessary $millions in advance, to build that feature into the ship. Plus crew training, safety certifications, insurance, etc. Imagine if a couple idiot kids or passed-out drunks were in the compartment which you de-oxygenated.

Last time I took a big car ferry the car decks were off limits for passengers. On a smaller ferry it's more of a problem but the risks are also lower.

Last time I took a ferry with car capabilities (between Hokkaido and Honshu) the car deck was very much accessible to passengers.

Li-ion batteries supply their own oxygen when they burn, you can't smother the fire.

There are deck walls strong enough to prevent a vehicle falling out of the ship, but usually open at either end to ensure good ventilation.

There are hundreds of these ferries operating in Europe (and other places with large islands or short seas/lakes), from tiny ones that carry 2-4 cars, to large ones with multiple decks.

https://www.alamy.com/stock-photo/car-ferry.html?sortBy=rele...

Tiny (UK): https://www.alamy.com/the-dartmouth-to-kingswear-car-ferry-l...

Small (Germany): https://www.alamy.com/stock-photo-car-ferry-harbour-friedric...

Medium (Brazil): https://www.alamy.com/stock-photo-car-on-board-the-ferry-mak...

Large (UK/France): https://www.alamy.com/stock-photo-the-vehicle-deck-of-a-cros...

Note these are public passenger ferries. You arrive at the port, buy a ticket, drive on and (usually) get out of the car for the journey.

Not easy. The vehicle decks on ferries can't be tightly sealed off. Modern ferries often have CO2 fire extinguisher systems fitted but those have limited capacity and the fire can reflash quickly when the oxygen level rises again.

Cars on a ferry are locked in by other cars, and in large ferries like this one a ceiling as well.

Have you ever actually seen a bunch of cars tightly parked on a ferry? If not, google 'cars on a ferry' and click some images. Now, imagine a car somewhere in the middle of the bunch catching fire. Are you going to volunteer 'pushing it overboard'?

Ignoring the other impracticalities that sibling commenters have pointed out, are you going to be the one to reach inside and put the flaming car in neutral? 'cuz you ain't pushing shit if that thing's still in Park.

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