• mommykink@lemmy.world
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    4 months ago

    Sounds like the best possible place to have a fire. Isn’t the only advice for putting out an EV battery fire “pour as much water as possible on it for several hours until it burns itself out”?

    • AA5B@lemmy.world
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      4 months ago

      Yes. Water doesn’t directly help it go out since the batteries are fine burning in water but if you carry away enough heat then you csn

    • cheddar@programming.dev
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      4 months ago

      I read on the news our local fire department had to keep one car in a special water reservoir for several days, because the fire kept reigniting.

    • MotoAsh@lemmy.world
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      4 months ago

      No, you don’t need to douse it in a substance it readily reacts with… I don’t know where this farce comes from, but it doesn’t corport wirth reality unless the point is to literally burn the fire out by fueling it. Like putting a bellows on a coal fire…

      • bleistift2@sopuli.xyz
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        3 months ago

        It is common practice to submerge EVs in water for several days in Germany, too. Remember that there is no elemental lithium (which would react with water) in batteries. As with every fire, the goal is to cool down the battery, so the fire doesn’t have enough energy to burn further. Unfortunately I only found German sources to back this up.

        • MotoAsh@lemmy.world
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          3 months ago

          Can batteries be extinguished? I thought the whole point was they were self-fueling and burn at least until the charge energy is gone.

          • bleistift2@sopuli.xyz
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            3 months ago

            This is my googled understanding, take with a grain of salt:

            Batteries contain of lots of individual cells. If you short-circuit one cell, you generate lots of energy (from the short-circuit), and start a chemical reaction (fire) that does produce its own oxygen. Once that cell has lost all its charge, the reaction would stop, but until then the fire has compromised neighboring cells, which start the process all over again.

            Water won’t stop the first broken cell from discharging, but it can bring the battery down to a temperature where the fire is too cold to sustain itself. It contains the damage to the cells that are affected already and prevents more cells from igniting. This is how you stop a battery fire.

            The car gets put into a tank for several days to allow the broken battery cells to discharge safely, without overheating and causing another fire.