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Water? On an electrical fire? Caused by Lithium-based chemistry? Not smart? Tesla's make up less than 0.008% of the US passenger car fleet. Perhaps emergen

Water? On an electrical fire? Caused by Lithium-based chemistry? Not smart? Tesla's make up less than 0.008% of the US passenger car fleet. Perhaps emergency workers are simply not aware of how to properly deal with electric vehicle accidents? Formula 1 had to deal with this as KERS starter to be introduced. I would be nowhere near a 375 Volt DC battery pack playing with water.

jasoncartwright 13y ago
http://www.teslamotors.com/sites/default/files/downloads/20130214_ModelS_Emergency_Response_Guide.pdf http://www.teslamotors.com/sites/default/files/downloads/201...
- robomartin 13y ago
  See my other response. Great, until you have a crash that looks like these [0] and you have a bunch of people trying to help victims while walking around in a wet 400 Volt DC environment. Now add more electric cars into the mix for a fun multi-electric car accident. Would YOU walk into that on Elon's recommendation? I'll tell you, I've been around high DC voltages, from a few hundred volts to tens of thousands. Water while handling components? No fucking way. Don't get me wrong. I love electric cars and would have been in line to buy a Tesla SUV had they not pulled that bone-headed design stunt with the falcon wings. At the same time I am a realist in that I understand that there's much to be learned about having thousands of cars with fully charged multi-hundred-volt power systems sharing the road at the same time. The emergency manual says that the pack can easily re-ignite and that it should be under observation for at least 24 hours. That's one of the issues with electrics. You can secure a gasoline powered car by simply draining all of the gasoline and dealing with it chemically. Imagine an electric car catching fire again as it is being towed away on top of a flatbed truck. We are going to have to develop new approaches to all of this. Tesla, I would think, will be at the forefront. So, not diminishing them, just stating reality. [0] http://www.google.com/search?q=serious+car+crash&safe=off&client=safari&rls=en&source=lnms&tbm=isch&sa=X&ei=l71-Uo7AHYjRsASDv4GgAw&ved=0CAkQ_AUoAQ&biw=1479&bih=964 http://www.google.com/search?q=serious+car+crash&safe=off&cl...
  - maxerickson 13y ago
    What do you expect to happen? To the extent that the battery is compromised, the water is mostly going to make it short to itself, and it isn't as if a raging battery fire is going to be a better situation for the apparently trapped occupant (the only time the immediate car environment is particularly troublesome). (The linked manual specifies using water to cool the battery and discusses observation procedures to limit the risk of re-ignition...)
    - robomartin 13y ago
      > What do you expect to happen? At one extreme, nothing. At the other, a potentially horrible electrocution. Run a google image search for something like "serious car accident" and insert an equally mangled battery pack in there. I very much doubt Tesla or any other electric car manufacturer would even remotely consider issuing a blanket guarantee stating that their design is electrocution-proof under all conditions. Not trying to be a troll. Simply saying that high voltage systems are extremely dangerous. That's it. No need to agree with me. Just remember I said it.
      - maxerickson 13y ago
        It would be nuts if the interconnects have higher survivability than the firewalls. Mangling the battery will almost certainly significantly reduce the voltage (I didn't quickly find anything on the Model S, but for the Roadster, the output voltage is achieved with a final series arrangement of sub-assemblies, breaking that should directly reduce voltage). Of course it will still create dangerous situations and experience will be valuable in judging just how dangerous.
  - stcredzero 13y ago
    How about some emergency equipment electric power dischargers? You could discharge huge amounts of energy in the form of steam. Just include a collapsible nozzle to direct the steam into the sky. Maybe this could be built into fire trucks?
    - 13y ago
djwhitt 13y ago
Elon previously indicated that it was ok to use water: "For the Model S lithium-ion battery, it was correct to apply water (vs. dry chemical extinguisher)..." http://www.teslamotors.com/blog/model-s-fire http://www.teslamotors.com/blog/model-s-fire
- robomartin 13y ago
  Well, good for him. I'd like to see him stand in a pool of dirty water in contact with a 400V DC power system trying to remove someone who might be hurt from the car. If you've ever seen what things look like around a serious car crash you know what I am talking about. Here, pick one and let's "use large amounts of water" as the emergency response manual recommends. http://www.google.com/search?q=serious+car+crash&safe=off&client=safari&rls=en&source=lnms&tbm=isch&sa=X&ei=l71-Uo7AHYjRsASDv4GgAw&ved=0CAkQ_AUoAQ&biw=1479&bih=964 http://www.google.com/search?q=serious+car+crash&safe=off&cl...
  - stcredzero 13y ago
    If the water is flooding the battery compartment and basically shorting between every positive and negative terminal of every cell simultaneously inside the armored battery compartment, I very much doubt this puts someone walking near the car at risk of themselves becoming a short circuit. Please think a little about the geometry of the situation. EDIT: Okay, physics challenged people out there: electricity tries to take the shortest route of least resistance. Please use reasoning more sophisticated than: "Water! Electricity! Oh Noes!"
    - robomartin 13y ago
      Please think a little bit about (a) not being condescending and (b) that the scenario you painted is ONE in a range of scenarios for a 400 VDC system with enough energy to propel a 4,000 pound vehicle a few hundred miles. I am not going to get into hypotheticals. All I am saying is that elecric cars have inherent dangers not found in gasoline cars. You can stand in a puddle of gasoline and you'll be OK.
JshWright 13y ago
Large quantities of water are the recommended way to mitigate battery fires in EVs. The primary reasoning that you want to cool the cells to stop the thermal runaway process. The worst case scenario is that the flood of water directly shorts the battery (which has likely already happened, if it's on fire).

jasoncartwright 13y ago

http://www.teslamotors.com/sites/default/files/downloads/20130214_ModelS_Emergency_Response_Guide.pdf http://www.teslamotors.com/sites/default/files/downloads/201...

robomartin 13y ago
See my other response. Great, until you have a crash that looks like these [0] and you have a bunch of people trying to help victims while walking around in a wet 400 Volt DC environment. Now add more electric cars into the mix for a fun multi-electric car accident. Would YOU walk into that on Elon's recommendation? I'll tell you, I've been around high DC voltages, from a few hundred volts to tens of thousands. Water while handling components? No fucking way. Don't get me wrong. I love electric cars and would have been in line to buy a Tesla SUV had they not pulled that bone-headed design stunt with the falcon wings. At the same time I am a realist in that I understand that there's much to be learned about having thousands of cars with fully charged multi-hundred-volt power systems sharing the road at the same time. The emergency manual says that the pack can easily re-ignite and that it should be under observation for at least 24 hours. That's one of the issues with electrics. You can secure a gasoline powered car by simply draining all of the gasoline and dealing with it chemically. Imagine an electric car catching fire again as it is being towed away on top of a flatbed truck. We are going to have to develop new approaches to all of this. Tesla, I would think, will be at the forefront. So, not diminishing them, just stating reality. [0] http://www.google.com/search?q=serious+car+crash&safe=off&client=safari&rls=en&source=lnms&tbm=isch&sa=X&ei=l71-Uo7AHYjRsASDv4GgAw&ved=0CAkQ_AUoAQ&biw=1479&bih=964 http://www.google.com/search?q=serious+car+crash&safe=off&cl...
- maxerickson 13y ago
  What do you expect to happen? To the extent that the battery is compromised, the water is mostly going to make it short to itself, and it isn't as if a raging battery fire is going to be a better situation for the apparently trapped occupant (the only time the immediate car environment is particularly troublesome). (The linked manual specifies using water to cool the battery and discusses observation procedures to limit the risk of re-ignition...)
  - robomartin 13y ago
    > What do you expect to happen? At one extreme, nothing. At the other, a potentially horrible electrocution. Run a google image search for something like "serious car accident" and insert an equally mangled battery pack in there. I very much doubt Tesla or any other electric car manufacturer would even remotely consider issuing a blanket guarantee stating that their design is electrocution-proof under all conditions. Not trying to be a troll. Simply saying that high voltage systems are extremely dangerous. That's it. No need to agree with me. Just remember I said it.
    - maxerickson 13y ago
      It would be nuts if the interconnects have higher survivability than the firewalls. Mangling the battery will almost certainly significantly reduce the voltage (I didn't quickly find anything on the Model S, but for the Roadster, the output voltage is achieved with a final series arrangement of sub-assemblies, breaking that should directly reduce voltage). Of course it will still create dangerous situations and experience will be valuable in judging just how dangerous.
- stcredzero 13y ago
  How about some emergency equipment electric power dischargers? You could discharge huge amounts of energy in the form of steam. Just include a collapsible nozzle to direct the steam into the sky. Maybe this could be built into fire trucks?
  - 13y ago

djwhitt 13y ago

Elon previously indicated that it was ok to use water: "For the Model S lithium-ion battery, it was correct to apply water (vs. dry chemical extinguisher)..." http://www.teslamotors.com/blog/model-s-fire http://www.teslamotors.com/blog/model-s-fire

robomartin 13y ago
Well, good for him. I'd like to see him stand in a pool of dirty water in contact with a 400V DC power system trying to remove someone who might be hurt from the car. If you've ever seen what things look like around a serious car crash you know what I am talking about. Here, pick one and let's "use large amounts of water" as the emergency response manual recommends. http://www.google.com/search?q=serious+car+crash&safe=off&client=safari&rls=en&source=lnms&tbm=isch&sa=X&ei=l71-Uo7AHYjRsASDv4GgAw&ved=0CAkQ_AUoAQ&biw=1479&bih=964 http://www.google.com/search?q=serious+car+crash&safe=off&cl...
- stcredzero 13y ago
  If the water is flooding the battery compartment and basically shorting between every positive and negative terminal of every cell simultaneously inside the armored battery compartment, I very much doubt this puts someone walking near the car at risk of themselves becoming a short circuit. Please think a little about the geometry of the situation. EDIT: Okay, physics challenged people out there: electricity tries to take the shortest route of least resistance. Please use reasoning more sophisticated than: "Water! Electricity! Oh Noes!"
  - robomartin 13y ago
    Please think a little bit about (a) not being condescending and (b) that the scenario you painted is ONE in a range of scenarios for a 400 VDC system with enough energy to propel a 4,000 pound vehicle a few hundred miles. I am not going to get into hypotheticals. All I am saying is that elecric cars have inherent dangers not found in gasoline cars. You can stand in a puddle of gasoline and you'll be OK.

JshWright 13y ago

Large quantities of water are the recommended way to mitigate battery fires in EVs. The primary reasoning that you want to cool the cells to stop the thermal runaway process. The worst case scenario is that the flood of water directly shorts the battery (which has likely already happened, if it's on fire).