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Comment by throw93232 | Hacker News Reader

EVs are safe if you remove batteries. If batteries can not be easily removed and serviced, it is unsafe design. We need basic regulations around safety here.

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I'm all for serviceable batteries, but I don't see how it solves the shipping safety issue.

So you ship the EVs without batteries, and then... you ship the batteries?

That might actually make sense. The main danger with batteries is thermal runaway, meaning if you keep them cool you can prevent the fire from starting. So what if you shrink-wrap each battery assembly to waterproof it, and ship them submerged in water (or another liquid of your choice). The water should easily absorb the heat from a couple damaged batteries without reaching a temperature that harms the other batteries as long as you leave some room for water circulation.

Thermal run away only happens on fully/close to charged batteries - so couldn't they just only ship <= 40% full batteries and be fine?

I think that might be done at some point.

So most shipments of cars are hazard free and cheap (to insure).

And then you have high risk battery shipments. With lots of expensive measures to minimize risks and fail safe.

(This is already today a thing, as you can ship items without batteries for less money.)

It is not clear to me, why it would be cheaper to ship the batteries separately. The car shipment might be theoretically cheaper, however it is much more difficult to ship cars which cannot drive. On the other side, you would have the increased risk for the battery shipment with the associated insurance costs. However, it is not obvious to me, that shipping electric cars is more risky. Actually all statistics point to electric cars being more safe than combustion engined cars.

As the article points out, it is probably necessary to change best practises of handling electric vs. combustion engined cars. Making really sure, that no car moves and crashes into others, change in firefighting strategies. Make sure, that the cars only contain a minimum amount of charge and of course continue to improve battery safety itself.

And you would not want to place the batteries densely together, in case of fire. Maybe put a few of them in some metal container or so, to keep them apart. Then one could put wheels on that container to move them more easily, maybe even add an engine.

"It is not clear to me, why it would be cheaper to ship the batteries separately. "

Special ships and specially trained and certified crews to savely handle de facto explosive equipment vs. totally hazzard proof expensive boxes of metal.

It might make sense to do this in big quantities. Probably will considered, after insurance companies raise rates after the first ship sank completely due to one carfire, that spread. Even with low charge they can burn out of itself. But sure, there are many other ways to deal with it.

You can stack the batteries in one place, in small compartments. If one compartment catches fire, it's easier to contain than in a big compartment with cars that take up much more space. It could even mean that you ditch the compartment in the ocean, to prevent a bigger problem. But compartments can be designed to be cooled with salt seawater without damaging the ship.

A battery is a heat source which requires no fuel to function. If you put an EV battery inside a sealed compartment, you just made a very large pipe bomb.

What if you put batteries into a container filled with sand? They probably would be safe there.

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