Featured No boat for you

A charging and discharging lead acid battery is both an electrolyser and a chemical conversion device changing the ratio of sulphur in the electrolyte, transferring it in or out of the lead plate.

I suggest you actually take the cap off a flooded cell lead acid battery and watch the bubbles produced during discharging as well as charging. Having worked with the things for 40 yr in the trade, I've seen enough explode during engine cranking.
There was a spate of "car bombs" that blew front mudguards and bonnets off car when first cranked over on a winters morning in Australia. The cause was finally narrowed down to a new battery developed by Dunlop I believe. It was called a Pulsar battery and made in vertical layers, much like the new blade batteries, but lead acid. The problem was narrowed down to poor resistance welds between the plates, creating heat and finally a spark that ignited the perfect mix of hydrogen and oxygen.
If you doubt just how much explosive power is in this mix, consider that an internal combustion engine will run on it if you can produce enough.

Referring to the graph on page 11 comparing the percentages of each gas, then the percentage of that gas compared to the total vapour ejected from the cell vent ..... how can you consider that represents 50% of what is ejected, even if you want to narrow it down to gases, ethene is more than double all the other gasses they actually measured. There is no mention of whether there were any other gases involved in the huge amount of "other" that makes up the total ejected from the cell during venting.
It might be interesting for you to read how the test was conducted and temperature involved in the test .... do you really believe the LFP cells experienced over 230*C while charging, check fig 4 and 5 page 7 and 8 .....

You could be right about the PEBCAK ...... but maybe not this end ......

T1 Terry

 

It isn't the amount, but were that energy might go. A large part of car fires start from a fault in the 12V system being near something else that can burn.

The traction pack should be disconnected from the drive train when the car is powered down. Any possible power leakage will be in the pack itself. Precautionary fire blankets on the cars and the tools for hosing the undercarriage down to cool any thermal runaway that happens should be plenty to address the issue for shipping.

Hybrids with Li-ion packs have been shipped around for decades now. If large format batteries in cars were a fire risk to ships, ther'd being data showing that.

 

Back when Toyota was trying to screw over EVs by pushing 'efficient' legislation (hydrogen) that required refueling within just a few minutes, Tesla came up with battery swap stations. You can still find YouTube videos where the process is around the same time that it takes to fill a car's large gas tank. Once Tesla was successful with meeting the requirements of the ridiculous hurdle, the legislation died. Point being? If there is some kind of thermal runaway, it seems to start with a sort of smoldering. That indicates there's a couple minutes before it becomes a blaze . Onboard Tech could certainly detect that scenario. If you can jettison pilots from troubled aircraft - why not a traction pack.
Just don't do that in your garage or hanger

 

A Farcebook post today regarding a lithium battery fire in a motorhome Neighbourhood Watch Moruya | Lithium battery Fire in a motorhome | Facebook Clearly, they didn't explode, but the very real problem with installing drop in batteries ..... the giveaway, dual lithium batteries ...... anyone who knows what they are doing, do not install dual lithium batteries, but rather, a single lithium battery designed and build to supply the voltage and capacity the application requires.
The over complicated engineering required to safely control more than one lithium battery that will absorb charging current like a sponge to the point of a cell venting, meaning the safety side of such an installation was never carefully thought through, otherwise, the cost alone would have pushed the single battery system well ahead of multiple drop in batteries

T1 Terry

 

If you watch the video, they flooded the EV with water, then again with foam additive in the water, it was still burning. If the cell chemistry produces it's own oxygen, then flooding with water will have no effect, the fire will continue in the waterproof battery box .......
The only way of containing a vehicle fire in the hold of a boat, is for the vehicle to be in its own fireproof blanket, that way the fire is restricted to that vehicle only, not a chain reaction fire that can't be controlled .... flooding the hold with nitrogen won't help either, still the problem with the battery chemical mix when heated producing its own oxygen.

If all the vehicles are loaded and everyone sealed in a fireproof blanket, when it's time to drive the vehicles back off, only the vehicles in the immediate vicinity of a vehicle that caught fire could possibly suffer heat damage .... but I would expect the fire blanket would protect the vehicle inside from any heat outside .....

T1 Terry

 

They have fire nozzles that slide under the blanket to hit the underside of the pack. The goal isn't to get water into the pack but to lower the temperature of the reaction. That will slow it down, and maybe even stop it. Which is actually how water puts out most fires; not by smothering, but by chilling the reaction until combustion can't continue.

Flooding the pack itself will work faster, but there is a couple of issues. One is that you end up with whatever materials inside the battery getting washed out into the environment. The other is that any open cells will have lithium metal to expose to the water. That leads to more heat and hydrogen gas.

 

it might be more cost effective to build the batteries in destination countries and ship the cars separately.
but how to drive them?

 

Many models are probably built around the battery.

 

you mean there's no way to replace it?

 

Another thought, if my car isn't safe enough to ship when put altogether, is it safe enough to keep in my garage or near my house?

I think keeping the car safe in all situations is the most important thing to do. I'm sure that some battery chemistries are less likely to catch on fire. And I'm sure there are certain ways to mitigate the chances of fire on all cars.

 

The battery bolts up under the floor in the majority of electric vehicles. The case is very heavy (thick) aluminium on the base and sides and a thinner lid on top. If the cell is creating it's own oxygen, cooling it won't stop the combustion. Just like oxy-acetylene cutting under water, with the added oxygen, the metal still oxidises at half the melting point of steel, even though it is surrounded by water ..... add sufficient oxidiser and the fire simply gets hotter and creates a vapour skin around the heated area to hold the water back .......

If you watch the video, you can see they attempt this idea of cooling the fire on a number of occasions, it simply didn't work. That is the hardest part to get through to first responders, you won't put the fire out if it is in the battery pack, all you can do is pull the safety switch to disconnect the battery pack part way through, get the people out, then contain the fire. In an open top lithium battery box, wet sand will work better than anything else, the sand creates a glass shell and the sand will continue to melt into sand until the heat is contained, no external fire, just let it burn itself out .....

China has already mandated that all electric vehicles produced after 1 July 2026 China sets world's strictest EV battery standard: "No Fire, No Explosion" rule effective July 2026, the major Chinese EV manufacturers already have their own ships to transport their vehicle to beat both this knee jerk type reaction as well as contain costs ....

T1 Terry

 

CATL seems to claim fireproofing is all dialed in, at least with their chemistry & their prophylactic measures.

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ICE cars catch fire in garages too.

 

Well, the structural packs Tesla is using will likely be cost prohibitive to replace. Even with the packs that do just drop down like a transmission, it is likely more efficiency to install them before the rest of the car is finished. Even not the case, production costs will go up with making most of the car at a factory, and then installing the large battery at another location. That's without considering what the lack of a battery case that supplies structural support means for safely shipping the car.

Ships, and moreso on planes, don't have good run away options when a fire happens. Thus their industries' heightened concerns.

Oxygen and acetylene don't burn without heat. Without a spark, a torch is just making bubbles underwater.

Oxygen and hydrogen aren't the only things burning inside a battery case. The anodes of all those cells are graphite, and there is plenty of plastic. For those to burn, the fire needs an outside oxygen source. Otherwise, the blanket would not be effective at containing the fire.

Even when the fire inside the pack becomes self-extending, you want to hose down the case to keep the heat from starting fires to other parts of the car. The under-carriage nozzle referred too is often used in conjunction with a blanket.

The shipping industry likely had concerns when it came to large numbers of cars being packed onto a ship.

 

and all this has to be done while trying to be more cost competitive with ice cars

 

i wonder what is happening with battery pack shipping