The international marine shipping rules for transporting EVs are a lot more strict than for transporting ICE automobiles. This is not necessary because a vehicle being electric or not, but because of the battery. Even in the Alaska US waters we have had lithium-battery fires in ships transporting batteries. The rules for transporting and shipping batteries are more strict for the same reasons. A simple example as follows: I live in Alaska, and quite a lot of companies in the States South of the Canadian border (we call them "Lower-48 States) do not ship the individual lithium battery packs to consumers in Alaska. I can buy (online) most instruments, laptops, cameras, and so on, however. But the only way I can buy a battery pack is at the local stores where I pay a higher price than in Amazon and other stores. I need to buy two cylindrical-shaped battery packs for a couple of metal detectors I have, but so far none are found at the Alaska stores.
By the way, my comments above have nothing to do with EV versus ICE vehicular fires. Fire departments around the world, insurance companies, the marine, land, and air transport industries...all have the safety instructions relating to the transport of chemicals, flammable materials, EV's, ICE automobiles, and so on. Anybody in this forum can easily search for and read all the safety instructions I have referred to.
This is very much uncharted (no pun intended)- or poorly charted territory. I’m not sure what specific regulations you speak of, beyond discharging the batteries to a level to minimize risk, disconnecting the batteries, ensuring the ambient temperature is acceptable, refusing vehicles with damaged batteries, labeling EV’s so crew are aware, having fire detection systems.
That’s all procedural type stuff to mitigate risk. The fact of the matter is that all risk cannot be mitigated and there have been a number of high profile battery fires on ships. Some couriers will not allow EV’s on board. Fires are without a doubt the most serious threat to ships.
It’s for the same reason why lithium ion batteries are forbidden from freight shipment on passenger planes and even passenger devices have to be carry-on. The fear is batteries could ignite in the cargo hold and no one would notice fast enough to deal with it.
As I’m sure you know, the problem with lithium-ion battery fires is that they cannot be fought with water (in the conventional sense) as it will only make the fire worse. No ships are currently in service designed to deal with EV fires nor do they have the equipment necessary- people are surprised to know most fire departments lack the equipment to adequately deal with battery fires.
It’s not just a fire or a fire inflamed by water that’s the problem, these fires burn exceptionally hot and produce highly toxic gases. And even if you put out the fire, thermal runaway can restart a many, many hours later. I’ve seen people propose jettisoning cars- not likely practical given the cars are packed in like sardines (also increasing risk of cascading fires) and something that could easily become very dangerous to crew in a moderate-heavy sea state. Moving heavy cargo while underway is not safe at all (numerous injuries with that Gaza Pier disaster).
I suspect we’ll eventually see ships designed for transporting EV’s. I imagine this would entail either packaging the vehicles in containers or keeping them contained compartments able to withstand the fire until specifically designed fire suppression systems can put the fire out.
This might require the ship be able to adjust its ballast or flood other compartments, preferably at least semi-automated, in order to prevent instability due to rapid and significant changes in weight distribution. Water is heavy.
My father used to be on the board of one of the biggest companies that made battery storage systems for the power grid (think Tesla Megapack). Their design basically put rack-mounted batteries inside an enclosure much like a shipping container- fully climate controlled. The fire suppression system used heptoflouropropane to quickly extinguish the fire. That however does not cool the batteries, so to prevent thermal runaway the interior is flooded from floor to ceiling with water from a fire hydrant main. Basically a similar concept as fire departments extinguishing EV fires and throwing the car into the ocean or dumpster full of water for day or two.
The idea that ships have EV safety on car transport ships is totally under control thanks to some best practices is fundamentally not the case.
And considering the stated very low level risk of thermal runaway, it’s concerning the London fire dept reported a fire incident rate of 0.04% for gas/diesel cars 0.1% for EVs. Then again, the rate of fires is far less of a problem (esp given EVs are such a minority) than is the difficulty managing the fires.
That said, this is not an unmanageable problem. Properly designed ships and advancements in battery tech and manufacturing will hopefully make the risk increasingly small.