back to article Tesla driver dies after Model S hits tree

The driver of a Tesla Model S electric car has reportedly died in a crash in the Netherlands this morning – and firefighters on the scene were nervous about being electrocuted as they fought the fire. Firefighters were said to be wary of the car's batteries having short-circuited thanks to damage caused by the crash, in which …

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  1. TRT Silver badge

    And after that article about...

    tackling Lithium-ion battery fires the other day that said "don't smother the buggers", or words to that effect.

  2. Anonymous Coward
    Anonymous Coward

    But...

    The smooth talking darling of the US business world, Elon Musk can do no wrong and apparently can walk on water, turn water into wine etc?

    Aren't Tesla fans (as opposed to EV Fans) getting close to worshipping him like Apple users and Steve Jobs?

    Before anyone asks, I do drive an EV just not stupid enough to pay Tesla prices (the Model 3 may change that).

    1. Anonymous Coward
      Anonymous Coward

      Re: But...

      Not quite sure what your problem is, but this is only news because it is a Tesla. The whole issue with EV accidents and battery power discharges is not exactly new, and your own EV happens to have the exact same problem.

      Tesla even has pages online with instructions for first responders in local languages, so even in Dutch.

      1. Stevie Silver badge

        Re: own EV happens to have the exact same problem

        Well, not if the batteries are not arrayed across the floor pan. if they are in the trunk/boot or under he hood/bonnet there is a reasonable expectation that the batteries will be better protected in a crash (probably wishful thinking on my part) and will stay in place while the rescue team is working. The Tesla's innovative layout poses some special concerns.

        But your point about a lithium battery is a lithium battery is well taken.

        1. Steven Raith

          Re: own EV happens to have the exact same problem

          "if they are in the trunk/boot or under he hood/bonnet there is a reasonable expectation that the batteries will be better protected in a crash"

          You mean when they are in the crumple zones? the parts designed to be utterly destroyed in a crash to prevent impact from travelling to and encroaching into the passenger compartment?

          "The Tesla's innovative layout poses some special concerns."

          You mean having the batteries well inside the crumple zones, in the area of the car specifically designed to avoid having to absorb the impact from an accident, because it also happens to be where the occupants are?

          I, um.....yeah.

          Just to be clear, car safety these days involves sacrificing everything ahead of the A pillar and behind the C-pillar (that is, the front and rear screens) so that the passenger area has less force to deal with, and thus the passengers have less force applied to them.

          Putting the batteries in the bonnet or boot areas, the areas most likely to be utterly gibbed during an accident, is a crazy idea. Even petrol cars usually have the petrol tank inside the crumple zones for this exact reason.

          Steven R

          1. Sorry that handle is already taken. Silver badge

            Re: own EV happens to have the exact same problem

            I wonder how heavy the impact was to have caused part of the battery pack to separate from the vehicle...

            1. Steven Raith

              Re: own EV happens to have the exact same problem

              High enough where you're not going to be walking away (or ever again) at best, I'd wager; safety tech has come along way, but airbags, safety cells, crumple zones, petrol diesel or battery powered....

              ...beyond a certain point, physics will always win.

              Edit: Oh, and for clarity:

              Even petrol cars usually have the petrol tank inside the crumple zones for this exact reason.

              I meant 'inside the area protected by the crumple zones', of course, but I'd hope that was clear from the context. On my car, the tank is below the rear seats, for example - which sounds crazy, but if you think about it, if an impact is so hard it warps the chassis badly and far enough in to damage the fuel tank, then we return to my original comment above - you're probably going to be dead from the impact long before the fire gets you.

            2. Black Betty

              Re: how heavy the impact...?

              Significant.

              The fun time for battery damage will be the first time a crotch rocket T-bones one at speed. I've seen passenger shells sliced almost in half.

          2. Myvekk

            Re: own EV happens to have the exact same problem

            Technically the force will remain the same, but the IMPULSE, (force exerted per second), is reduced on the passengers.

          3. Stevie Silver badge

            Re: own EV happens to have the exact same problem 4 Steven Raith

            You mean having the batteries well inside the crumple zones, in the area of the car specifically designed to avoid having to absorb the impact from an accident, because it also happens to be where the occupants are?

            No, I mean what I actually wrote, explicitly. The Tesla's batteries are in the floorpan which is anything but "inside the crumple zone". Two Tesla fires that I can remember came about because of the road contacting the floorpan at speed. No crumpling was involved, but there was plenty of burning.

            The crazy idea you seem to feel is worse than sticking sheets of lithium under the seats is the way other manufacturers are doing the trick. The reason the Tesla isn't is so that the car has some luggage space, a problem with those other vehicle designs. Tesla is also enabling people to drive much faster than people do in those other designs.

            Which is why they need that proximity-triggered "Yeehaa!" klaxon.

            1. Steven Raith

              Re: own EV happens to have the exact same problem 4 Steven Raith

              Stevie, I'd suggest you have a look at accident statistics and see how many are frontal and side impacts, and how many involve the central underside of the car getting extensively damaged.

              The fact that you can only find two fires out of all the Teslas on the road (especially given the huge publicity any major Tesla crash gets) suggests that it's really not a major problem. How many others would have had fires if the batteries were in the boot or underbonnet area, where the vast majority of impacts occur? It's not a massive stretch of reality to suggest 'rather a lot more'.

              The Tesla battery pack is surrounded by chassis rails in the (beefy) sills, and the crumple zones in the front and rear, with a titanium skid pan underneath (a result of one of the fires, actually) - something you won't find under most petrol cars, I might add.

              It's about as safe as it can be made while still having headline grabbing performance and a range comparable with a similarly performing petrol car, in short - and generally safer than most petrol powered passenger cars thanks to not having a massive lump of metal in the front that's difficult to build crumple zones around.

              You can never have an entirely safe car, regardless of energy source because that energy source will always have to be very high capacity and will always be a volatile problem in an accident.

              So you mitigate the risk as best you can; by having the power cells away from the areas most regularly damaged in the vast majority of all accidents - the front and rear and the extremities of the sides of the car - you mitigate the risk for vast majority of all accidents. You can't stop physics if you go sideways into a tree at highway speeds - nothing can - but at that stage, your chances of survivability are going to be slim no matter what the power source - and if your out cold from physical shock and the car starts burning, whether it's LiPo or petrol/oil/ATF that's burning, you're pretty fucked regardless.

              If you put the energy source in the boot or under the bonnet, you are exposing them to the danger zones in the vast majority of accidents, be they low or high speed - and significantly increasing the chances of unnecessary fatalities due to an out of control LiPo fire in significantly 'smaller' incidents. But LiPo is the best we've got for now, and I doubt we'll ever have a battery source with that much power that isn't a bit 'interesting' when destroyed.

              It's not risk removal, it's risk mitigation. Your plan of having batteries in the boot or underbonnet area significantly increases risk in all situations except those where there is a (very rare, statistically) serious underbody strike hard enough to literally rip through the floorpan. Teslas plan mitigates risk for the vast majority of situations where someone bashes you from the front, behind, or t-bones you.

              That's why I pulled you up on that point - other manufacturers are putting their batteries in the boot or the seats or wherever because they are working with existing floorpans that don't have space for it in the chassis, not because it's inherently better.

              Steven R

            2. Alan Brown Silver badge

              Re: own EV happens to have the exact same problem 4 Steven Raith

              "The crazy idea you seem to feel is worse than sticking sheets of lithium under the seats is the way other manufacturers are doing the trick. "

              Most of them are putting the batteries in the floorpan. It keeps the CoG low. The only ones who aren't tend to be conversions of existing bodyshells.

        2. bombastic bob Silver badge
          Trollface

          Re: own EV happens to have the exact same problem

          "But your point about a lithium battery is a lithium battery is well taken."

          right, lithium being the second most chemically reactive substance in the known universe, and the most reactive of all of the metals. This makes it a very good battery material, not so good on safety following a catastrophic failure to contain the material in an airless environment, nor prevent an unintentional extermely-low-resistance circuit from forming between the + and - terminals following such an event.

          We've already seen battery troubles on the (I think it was) 777 airliners causing a fire. We all know that on occasion a malfunctioning LiPo or LiIon battery can burst into flames, destroying whatever equipment it's mounted in. We also have airline regulations preventing the shipment of batteries 'over a certain amp-hourage' in airline carryon. Such regulations require that these batteries be shipped in approved containers, fireproofed, etc..

          So I guess it's kinda like a Corvaire or a Pinto in that respect...

          What's next, "unsafe at any speed" for the TESLA? Or do we build fireproofing material and special 'crumple' things for the batteries?

          Ralph Nader types, where are you? Chances are they're conflicted between contradictory positions on environmentalism and consumer safety...

          1. Steve K Silver badge

            Re: own EV happens to have the exact same problem

            Sorry, Lithium is neither the second most reactive element nor the most reactive metal.

            One of the problems you have in a charged LiPo is the stored energy in the cell which complicates handling a fizzing or popped cell even if not currently burning.

            1. Stevie Silver badge

              Re: own EV happens to have the exact same problem 4 Steve K

              One of the problems you have in a charged LiPo is the stored energy in the cell which complicates handling a fizzing or popped cell even if not currently burning.

              Better hope your protection electronics are in good shape if you ever try charging a fully discharged LiPo battery.

              This battery design is riddled with the most gotchas of any so far commercially available. When delivered in a "lightweight" configuration we are basically talking a fire waiting to happen.

              Aside: My dad used to teach industrial electronics at college level. He came home one night to report that a discharged Duracell Alkaline AA battery (then a fairly recent innovation) had been sitting on his lab eye-level shelf when it spontaneously exploded. His students changed their trousers, then theorised an internal short, but thereafter he had them swap out the batteries on the instruments before they discharged beyond a certain point. Student eyeballs were two a penny it was true, but a decent multimeter was hard to replace.

              1. Chris 239

                Re: own EV happens to have the exact same problem 4 Steve K

                I call total BS on the discharged Alkaline AA exploding!!

          2. Anonymous Coward
            Anonymous Coward

            Lithium's reactivity

            Lithium being the second most chemically reactive substance in the known universe, and the most reactive of all of the metals.

            You clearly have never worked in a chemistry lab or a machine shop dealing with magnesium or titanium alloys. Bulk metallic lithium is pretty benign as chemical reagents go: you can safely handle it in air for fairly extended periods of time (although you most definitely do not want to store it in air). It is also not that easy to ignite, and its reaction with, say, water is only mildly violent.

            Any of the heavier alkali metals (potassium and especially cesium and rubidium) are much more reactive; it would be an extremely bad idea to expose them to air for any length of time (among other things, they form a peroxide when in contact with air - which explodes upon slightest provocation. If you even had to work with metallic potassium, the very first thing you learn is how to recognize that tell-tale peroxide crust.)

            Lithium fires are also not that hard to deal with: they can be extinguished by sand, dry-powder extinguishers, or alcohol-based foams. Magnesium and titanium fires are much, much harder to extinguish: once ignited, titanium will happily continue burning in carbon dioxide, nitrogen, water, sand, and asbestos.

            There literally millions of chemical substances which are either more reactive or more toxic than lithium, and quite frequently both.

          3. Anonymous Coward
            Anonymous Coward

            Re: own EV happens to have the exact same problem

            I remember seeing a potato-powered clock. I wonder if EV safety could be improved if they were to run off a bag of spuds in the boot.

            1. Stoneshop Silver badge
              Pint

              Re: own EV happens to have the exact same problem

              I wonder if EV safety could be improved if they were to run off a bag of spuds in the boot.

              You might get an electric vehicle to move if it's not much heavier than that sack of potatoes. Better to turn them into alcohol and use that as fuel for an IC engine.

              1. IT Poser

                Re: own EV happens to have the exact same problem

                Better to turn them into alcohol and use that as fuel for an IC engineyourself.

                Why go through the trouble of growing potatoes then turning them into alcohol if not to enjoy the primary benefit?

          4. Stoneshop Silver badge
            Boffin

            Re: own EV happens to have the exact same problem

            right, lithium being the second most chemically reactive substance in the known universe, and the most reactive of all of the metals.

            It is not.

            Reaction with water gets more violent with the periodic table row going up

          5. roytrubshaw
            Mushroom

            Re: own EV happens to have the exact same problem

            "right, lithium being the second most chemically reactive substance in the known universe, and the most reactive of all of the metals."

            Err. No. Lithium is the least reactive of the Alkali metals (Group II); in this case reactivity increases as you go down the group. So Caesium would be the most reactive of these metals.

            There is an entertaining film I remember from my school days where each metal in turn is reacted with water, which demonstrates this point quite explosively

            Here's a YouTube video that contains some of the scenes from that film: (https://www.youtube.com/watch?v=HvVUtpdK7xw)

    2. AndyS

      Re: But...

      Cars crash. People die in car crashes.

      In this case, a man has, tragically, died in a car crash. That is all we know.

      Actually that's not all we know, we also know that Tesla is working their damn hardest to reduce the number of people that die in crashes, and it's only because of that, that every crash in one of their cars gets reported round the world. If they were just another OEM pumping out dino-powered boxes, you'd hear, and think, nothing. How many people do you think have been killed worldwide in accidents by hitting stationary objects in their perfectly normal cars today?

      And yet you want to have a go at bashing them. Well, good for you.

      1. Anonymous Coward
        Anonymous Coward

        @AndyS

        I'm actually from the Netherlands and could follow the news around this...

        "In this case, a man has, tragically, died in a car crash. That is all we know."

        Oh, we know a lot more. It took 5 hours before the fire department finally could start to remove the body. It's also not 100% sure yet if the man actually died during the crash or after because... As it turned out the safety system which should have done a total shut down failed, due to the crash (ironic in my opinion), and because the batteries of the car had caught fire the fire department feared risk of electrocution, therefor couldn't do much. As such it took them 5 hours.

        I do agree that you can't blame Tesla here, though the failed failsave sounds peculiar to me. However I do think people might want to re-consider driving electric cars considering the extra hazards it could cause.

        If this had been a normal petrol car then the fire department could have acted a whole lot quicker.

        1. mark 177

          Re: @AndyS

          and the fire services would have to react far more often - petrol cars have a far higher chance of catching fire than electric ones.

        2. Anonymous Coward
          Anonymous Coward

          Re: @AndyS

          I do agree that you can't blame Tesla here, though the failed failsave sounds peculiar to me. However I do think people might want to re-consider driving electric cars considering the extra hazards it could cause.

          Dunno. I personally think the actual recommendation should be to drive in a way that allows you to avoid perfectly stationary trees, mainly because reasonably sized trees tend to win, irrespective of what propulsion you use. Using that strategy, I have managed to drive close to 4 decades without ever having to worry about trees.

          Tesla has posted some rather impressive crash test results, so I'm not convinced you can class them as unsafe.

          1. Stoneshop Silver badge

            Re: @AndyS

            Dunno. I personally think the actual recommendation should be to drive in a way that allows you to avoid perfectly stationary trees,

            Given that Tesla now reports, via AP, that the driver was doing 155km/h* (nearly 100mph for youse non-metric types) prior to the crash he was either unaware (unlikely) of this recommendation, temporarily unable to heed this advice for any number of reasons, or he decided to throw it to the wind..

            BTW, I do worry about trees next to the road, but rather in a way that makes that I'm aware of their presence and not having cause to meet them through other events.

            * if correct, that's nearly twice the speed limit for that road.

          2. ICPurvis47

            Re: @AndyS

            Trees are actually helpful in some accidents, I once had to use one as a ground anchor to attach a winch to when I was working as a breakdown mechanic and had to extricate somebody's car from the ditch that they had driven it into.

        3. Adam 1 Silver badge

          Re: @AndyS

          > However I do think people might want to re-consider driving electric cars considering the extra hazards it could cause.

          People may well but people are not as rational as we like to believe. Are you considering the additional deaths from NOx emissions or do we feel like externalising those? Not to mention the bakery of bunnies, kittens and unicorns that are the oil producing regions that get subsidised.

          I would have thought that not having a massive block of incompressible cast iron or aluminium in between you and the other object limits the amount of energy that can be absorbed by the crumple zones when compared to an empty void. That increases survivability in such other cases.

          1. Stoneshop Silver badge

            Re: @AndyS

            I would have thought that not having a massive block of incompressible cast iron or aluminium in between you and the other object limits the amount of energy that can be absorbed by the crumple zones when compared to an empty void.

            I think you have that the wrong way round. With that massive block of incompressible cast iron or aluminium, an impact that displaces the front of the engine will displace the back by more or less the same amount (give or take the deformability of mostly bolted on stuff). With a bonnet holding separate bits of gear such as boxes of electronics and the ventilation/aircon system for the passenger compartment, you can design the front crumple zone for optimum energy absorbtion; any incompressibility of the bits in it is way less relevant.

            1. Adam 1 Silver badge

              Re: @AndyS

              > I think you have that the wrong way round.

              Yes I do. Ended up with an extra not in that sentence which changes the meaning. Also, autocarrot changed one of my words to bakery which reads pretty random.

              But I think you picked my basic point; that if your engine bay contains an engine block, you have to try to jettison it under the safety cell. But it is still going to crush your feet on the way through because you can't quickly change the direction of many hundreds of Kg. The more energy that can be absorbed in front of the safety cell, the slower the rate of deceleration experienced by the passengers.

          2. Stevie Silver badge

            Re: @AndyS 4 Adam1

            I would have thought that not having a massive block of incompressible cast iron or aluminium in between you and the other object limits the amount of energy that can be absorbed

            But the engine is held to the frame by three or sometimes four bolts, which are designed to shear in a crash. The (red hot) engine goes under the car (usually, there are some howler designs that push it up through the bonnet so it can come through the windscreen and land in the driver's lap), directed there by the slope of the firewall.

            Designs with a conventional gearbox will hopefully dislodge the rear axle or the assembly may attempt to come up through the tunnel cover for a hug.

            You don't want solid stuff in the way. The point of the crumply stuff is to streeeeeeeeetch out the time it takes to go from "Yeehaaohchrist!" to zero and thus reduce the force experienced by the occupants (F=ma, a=dv/dt so for a given dv the dt needs to be as long as possible to minimise F). That's why seatbelts are stretchy and airbags leak.

            Interestingly, the telescopic steering column is a different case. It collapses because before they did that it was not uncommon for crashing drivers to be killed by a kung-fu punch to the chest by the steering wheel. Then the sun visors and dashboards had to become soft because with no wheel holding back the driver his/her head was free to hit them. The old plywood sun visors were first to go, followed by the wooden dashboard.

            And so was born the Nanny State, where a person was no longer free to trepan themselves on the visor or do some amateur dentistry on the old instrument cluster.

            Now, of course, the only serious threat to most drivers is the danger of having two small trumpets cold-stamped into their temples when the air-bag deploys and blows off the horn push.

        4. mwnci

          Re: @AndyS

          There is no-fail safe if Batteries vessels are ruptured....

          1. Androgynous Cupboard Silver badge

            Re: @AndyS

            I'm not sure if the Tesla uses LiFePo4, but they're likely using a variant which is similarly stable. You can optimise for stability or power density, and car batteries are typically optimised for stability - these are not the explode-in-your-pocket cellphone batteries.

            If you need convincing, This video is worth a watch, if only for the bit where the guy unloads a gun into the battery. He doesn't even have a high-vis vest on, try doing that in Europe. It's from Sinopoly, one of the largest manufacturers of LiFePo4 cells.

            1. Stoneshop Silver badge

              Re: @AndyS

              I'm not sure if the Tesla uses LiFePo4, but they're likely using a variant which is similarly stable.

              According to batteryuniversity.com, they're using NCA,

              "Lithium nickel cobalt aluminum oxide battery, or NCA, has been around since 1999 for special applications. It shares similarities with NMC by offering high specific energy, reasonably good specific power and a long life span. Less flattering are safety and cost. Figure 11 summarizes the six key characteristics. NCA is a further development of lithium nickel oxide; adding aluminum gives the chemistry greater stability.

              Snapshot of NCA

              High energy and power densities, as well as good life span, make NCA a candidate for EV powertrains. High cost and marginal safety are negatives."

        5. Jaybus

          Re: @AndyS

          "It took 5 hours before the fire department finally could start to remove the body."

          I will hazard a guess that the fire department might have tried harder had they been sure the man was still alive. Otherwise, they were correct in being safe. The man was not going to get any deader.

      2. Anonymous Coward
        Anonymous Coward

        @AndyS

        Another post, while the thread is more or less 'done', but even so... Usually the aftermath is just as important (if not more) than the moments shortly after the event itself.

        "And yet you want to have a go at bashing them. Well, good for you."

        Well, no bashing from me, but in the aftermath of this incident Tesla has shown to have very little consideration for the drivers family. Which I think is appalling. Here's the problem: while the police were still busy investigating the crash and had not given any official statement yet Tesla considered it necessary to send out a press release in which they declared that the driver was speeding together with other information involving the crash. Before the police had given any official reports, even before the police had a chance to contact the next of kin.

        In my opinion Tesla only had their own reputation in mind here and apparently couldn't care less about the drivers family. Who got to hear some details first from a company's press statement before being contacted by the police.

        I think that's disgusting on the part of Tesla. They could have waited a week or so before releasing this but no... Their reputation obviously came first.

        So yeah, you still think they're doing everything they can to keep people safe? Or are they doing everything they can to preserve their own reputation?

        1. Hans 1 Silver badge

          Re: @AndyS

          WTF ? Tesla talked about the technical stats of the accident, they did not say John Doe was a silly wanker who drove too fast and bent the car around a tree. So, you basically also want journos to remain silent on the crash up-until the police have finished their investigation, the next-of-kin has been informed etc ?

    3. Def Silver badge
      Facepalm

      Re: But...

      Smooth talking?

      Have you heard him give a presentation before?

    4. Anonymous Coward
      Anonymous Coward

      Re: But...

      Jealous much?

    5. Dazed and Confused Silver badge

      Re: But...

      > Elon Musk can do ... and apparently can walk on water

      If you put enough lithium on your shoes, you too can walk on water

      or least stay afloat for the while before you catch fire in a really pretty colour.

  3. Hans Neeson-Bumpsadese Silver badge

    standard operating procedures

    What are the differences, in terms of firefighting, associated with tackling a Tesla compared to, say, a milk float, mobility vehicle, or whatever? I would have expected a fire service to have standard operating procedures for dealing with RTCs/fires for such vehicles.

    Maybe SOP in such cases is also to admit defeat and phone the manufacturer

    1. Test Man

      Re: standard operating procedures

      I agree. I mean, they are firefighters, how would they tackle an electrical fire in any other situation? Why didn't they just use the already-existing steps to tackle electrical fires? It's not as if a Tesla car is anything special in that regard.

      1. AndyS

        Re: standard operating procedures

        > how would they tackle an electrical fire in any other situation? Why didn't they just use the already-existing steps to tackle electrical fires? It's not as if a Tesla car is anything special in that regard.

        It's a fairly non-standard electrical fire. First, it's high voltage DC, not AC, which makes it more dangerous. Secondly, there is no way to isolate it (as they would at sub-station fires etc). Third, it's on fire (the electrical source itself, not just stuff around it), and it's got lithium in it. Fourth, there was no danger to anybody by letting it burn (bearing in mind the driver had already died in the crash), so that appears to have been the safest way forward.

        Not sure what else they should have done, really. Seems like they acted very sensibly.

        1. TRT Silver badge

          Re: standard operating procedures

          @AndyS. FYI - From the first responder guide:

          If the Roadster is connected to a charging device, DO NOT use water to extinguish a vehicle fire. Exercise the same precautions used when AC power supply potential exists.

          If the Roadster is NOT connected to a charging device, Battery Pack voltage will not follow water back up a fire hose.

          Fire fighting measures

          If fire or smoke is observed when the Tesla Roadster is connected to a charging source, immediately shut off power to the charging source.

          In the case of burning lithium-ion fires, generously and continuously flood the area with water. The water may not extinguish the fire, but will cool the adjacent battery cells, control the spread of the fire, and prevent the fire from being re-ignited.

          Firefighters should wear self-contained breathing apparatus. Battery cells may emit potentially hazardous organic vapors if exposed to excessive heat, fire, or over-voltage conditions. These vapors include HF2 oxides of carbon, aluminum, lithium, copper, and cobalt. Additionally, volatile phosphorous pentafluoride may form at temperatures above 230o Fahrenheit.

          Battery first aid

          Under normal conditions, the Tesla Roadster’s battery cells are hermetically sealed. Contents of an open (broken) constituent battery cell can cause skin irritation and/or chemical burns.

          If materials from ruptured or otherwise damaged battery cells contact the skin, flush immediately with water and wash affected area with soap and water. For eye contact, flush with significant amounts of water for 15 minutes and see a physician immediately. Avoid inhaling vented gases. If a chemical burn occurs or if irritation persists, see a physician.

          1. Steve K Silver badge

            Re: standard operating procedures

            "These vapors include HF2 oxides of carbon, aluminum, lithium, copper, and cobalt. Additionally, volatile phosphorous pentafluoride may form at temperatures above 230o Fahrenheit."

            May I just say "Oooh f@ck!"

        2. Black Betty

          @AndyS Where's the return path?

          The manual specifically states that it's safe to use water any time the vehicle is not connected to an external supply.

          Next issue: It's already isolated to the confines of the vehicle. The only possible danger is coming into contact with exposed wiring and the chassis simultaneously. If there's a short to chassis the battery manager should have already fully isolated the battery. furthermore If it's physically disrupted, chances are good it's already open circuit. Even cutting a live wire is mostly a non-issue, except for what the sparks might ignite before the BMS cut in.

          Perhaps a magnetometer in the "wa-wa" wand they already have to see if an AC cable is live.

          Confronted by a relatively small hazardous materials fire they acted like a bunch of nervous nellies.

        3. Anonymous Coward
          Coat

          Re: standard operating procedures

          They could have worn their waterproof rubber boots along with their insulated gloves. And often their coats are a bit waterproof/insulated. So no problems doing a close inspection at least. Which is probably what they actually did.

          Its not as if it was a full out dangerous goods spill even with all the Li.

          Mines the one with the bromine tank in the pocket.

      2. Anonymous Coward
        Anonymous Coward

        Re: standard operating procedures

        The SOP for electrical fires is simple:

        1. Turn off all power

        2. Proceed as you would for any other fire

        The problem is that #1 is quite hard to do when your power source (ie the battery) is wrapped around a tree and is currently on fire.

      3. bombastic bob Silver badge
        Alert

        Re: standard operating procedures

        "they are firefighters, how would they tackle an electrical fire in any other situation"

        well it's not entirely an electrical fire.

        Fire classes are 'A' (wood, paper) 'B' (oil, natural gas), 'C' (electrical), and 'D' (chemical, pyrotechnics)

        http://www.falckproductions.com/resources/fire-safety-and-firewatch/classes-of-fire-a-b-c-d-and-k/

        apparently also a class 'K' now, for cooking fires [usually these have PKP dump extinguishers activated by heat or a pull-chain/lever of some kind]

        What we have here is a case where there is a class 'C' fire _AND_ a class 'D' fire. Putting dry chemical on lithium will probably make it WORSE. Also dry chemical is conductive, and so it would make the electrical fire worse. CO2 usually works best on electrical, and probably the Lithium fire as well. Problem with class 'D' is knowing _exactly_ what chemicals will put it out, and what chemicals make it worse. You could actually put some fires out with OIL, if you think about it, because it has excellent smothering and cooling effects, so long as it's not atomized with plenty of O2 [in which case you'd get an EXPLOSION and a class B fire to go with it].

        Class D fires may be self-oxygenating. in the case of a LiPo, this is probably the case when you get past a certain point. Li reacts with just about everything, from the negative electrode to the material it's sealed up with, the atmosphere, WATER, and anything else you throw at it.

        When I was in the Navy I was trained in firefighting [as everyone else was] and we did regular training and drills and whatnot. I've actually put out a couple of fires (not while in the Navy) when there was an arsonist in my neighborhood, a few decade ago. I wouldn't call myself an expert, just 'knowledgeable'.

        But I can totally understand why firefighters were hesitant to try and put out a battery fire like that. Sometimes, if life is not immediately threatened, if property damage can be avoided by "letting it burn" and keeping it from spreading, THAT is what you'd do, to avoid "something worse" if you do the wrong thing...

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