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After bus fire, CT pulls electric fleet from service
- atlasunshrugged 4y agoIMO this is an aspect of the shift to EV's that I don't hear all that many people talking about- is the gov giving enough resources/training to local emergency services providers to deal with these sorts of fires and the disposal of the EV materials after a fire. Totally surmountable, but I feel like I don't hear the federal gov talk about it much and instead the focus is on more chargers and tax credits to eliminate range anxiety and drive the cost down for consumers
- nathanaldensr 4y agoThe entire point is that you can't "deal" with it. Since car batteries contain the fuel and the oxidizer, there isn't a way to separate them short of blowing the whole thing up. Fires can stop and start spontaneously, and often do (see pictures and videos of Teslas on fire in junkyards).
- bragr 4y agoThis is not really true. There are tools and agents to address lithium fires, but you have to have them. If you just try to put them out with water, you're going to be there all night fighting reignition.
- DoneWithAllThat 4y agoPlease don’t leave us in suspense: what are these tools and agents? Got a link?
- marcosdumay 4y agoFor lithium, sand is enough. If you have HF like a sibling said, sand won't do, but I can't imagine you would get enough of it to sustain a fire.
- bragr 4y agoLithium fires are considered class B so any chemical agent such as found in any standard ABC or dry chemical fire extinguisher would be sufficient. As for tools, there's stuff that can be used to pierce the battery case and inject water or agents directly into the battery. https://arstechnica.com/cars/2021/11/new-firefighting-tool-delivers-water-directly-to-blazing-ev-batteries/ https://arstechnica.com/cars/2021/11/new-firefighting-tool-d...
- KennyBlanken 4y agoLithium ion battery fires are not lithium fires. Water is the recommended method because it is the most effective way to stop thermal runaway. If you don't believe me, google "lithium ion battery fires water"
- deleted 4y ago[deleted]
- londons_explore 4y agoElectric cars could totally be designed to be re-ignite-proof. For example, you'd have the battery pack detect a breach - for example through a lack of pressurised coolant. That would then trigger each battery cell to have a PTC resistor discharge it - that could be entirely mechanical. The PTC resistors would discharge the battery in a few hours, maintaining the battery temperature at say 120C. As water is doused onto the battery, it will boil off. As soon as the battery temperature cools below 120C, then every cell is guaranteed to be discharged.
- kayodelycaon 4y agoHow well do these safety feature survive 2,000+ºF fire burning next to them?
- dymk 4y agothere’s a period of time between normal operation and 2000 degree fire where this could be detected
- DoingIsLearning 4y agoPCB solder will reflow at about 240°C or 470°F so provided you have a thermal resistant container around the pcb it will probably outlive the fire long enough to fail-safe, these kind of hardware mitigations will probably latch with a latency in the microseconds scale.
- marcosdumay 4y agoBadly. How well does gasoline containers survive it? If you have a 2000°F fire, you probably have buildings collapsing and a lot of fire everywhere surrounding it. As long as things do not explode, you can't make it much worse by any action. And exploding is something the batteries don't do.
- KaiserPro 4y agoSo in a thermal event, where integrity of the coolant is compromised, you want to dump more heat into the system? Its not just the electrical issues at play, its the fact that hot battery fluid burns spontaneously with exposure to air (I suspect also water, but I'm less sure about that)
- quartesixte 4y agoAdd to the fact that the fuel is Lithium and you’re in for a badddddd time
- kwhitefoot 4y agoThere really isn't as much lithium in a battery pack as people seem to think. The 450 kg pack in a Model S has about 60 kg of lithium. Dutch fire fighters dump the whole car in a skip full of water to cool it down once they have contained the fire so that it burns out but doesn't set light to anything else. 60 kg is roughly 9 kmol and 1 mol has a heat of combustion of 300 kJ/mol so if burnt in air it would release 3e5 * 9e3 = 27e8 J which is about 75 kWh (coincidentally about the same as the battery capacity). Enough energy to raise a ton of water by 67.5 K. So if you can submerge it in water it will pose no further risk. I presume that the lithium water reaction releases a similar amount of energy if the hydrogen burns, someone with a better knowledge of the chemistry could correct me.
- deleted 4y ago[deleted]
- DoingIsLearning 4y ago> is the gov giving enough resources/training to local emergency services providers to deal with these sorts of fires and the disposal of the EV materials after a fire. The main immediate threat is not disposal or even fire itself but the release of hydrogen fluoride _during_ a fire. You have to avoid airway and eye exposure at all cost with HF. This is probably the main difference in an EV emergency response as opposed to other chemical fires. The second main issue is securing an electrically safe chasis during crash and vehicle extraction (if you need to start chopping the car up to extract someone), you need to know what to cut and when. This unfortunately varies wildly, model to model, with manufacturers adding battery packs in multiple locations for space and weight management. I know there has been a lot of effort in standardizing charging systems, perhaps we also need some form of emergency service kill switch, but this being HN that could also introduce a massive potential for abuse.
- bdamm 4y agoMany models have a pyro fuse in the battery pack high voltage hook-up that blows when the airbags deploy. Also common is that if the 12V battery is disabled, the high voltage pack is also disabled. And many models simply disconnect the high voltage pack when in park (or soon thereafter). So while you're right that there's not a common standard, the common reality is that the packs aren't dangerous in a crash. Regulation could push this just a little further and mandate pyro fuses in pack hookups, which would reduce the probability of electrocution to first responders and occupants to basically zero, since nobody would try to cut through the floor of the vehicle in an extraction (where the pack cells are, and the most dangerous part when it comes to randomly cutting cross sections.)
- KennyBlanken 4y agoAll EVs and hybrids have contactors inside the battery pack and if it is not energized, there is no high voltage present anywhere in the vehicle outside the pack.
- KennyBlanken 4y ago> The main immediate threat is not disposal or even fire itself but the release of hydrogen fluoride _during_ a fire. You have to avoid airway and eye exposure at all cost with HF. This is probably the main difference in an EV emergency response as opposed to other chemical fires. At any chemical or vehicle fire, firefighters are wearing SCBAs. > The second main issue is securing an electrically safe chasis during crash and vehicle extraction (if you need to start chopping the car up to extract someone), you need to know what to cut and when. HV cables are extremely clearly marked (bright orange, a color not used for any other component.) HV cables run directly from the battery to the inverter. Extraction involves prying doors / cutting door hinges / cutting roof pillars. Not chopping up the floor. HV cables are not energized after a crash because every battery, EV or hybrid, has an internal contactor that fails safe. There is also usually a clearly marked physical plug that can be pulled. I love it when people jump on internet forums and talk authoritatively and demonstrate they know absolutely nothing about the subject at hand.
- Proven 4y ago
- draw_down 4y ago
- GiorgioG 4y agoAs much progress has been made in EVs, I have no interest in sitting atop of a napalm bomb while zipping around town. There's a few problems that keep me from being remotely interested in EVs, this is one of them. The others are range anxiety, energy storage portability and battery replacement costs. If I run out of gas on the side of the highway, I call AAA and they can deliver me a couple of gallons of gas or I can walk to a gas station. If your EV runs out of juice, you have to have it towed to a charging station.
- ShakataGaNai 4y agoThe napalm bomb you're speaking of is made of gasoline. Which is in most cars and vehicles on the road. So you're less afraid of something designed to catch fire and explode (gas) than something that is designed to operate safely at it's core (batteries)? That just doesn't make sense. Other than being afraid of new technology. And that's totally ok. Its fine to say you don't like change or new technologies. There is absolutely nothing wrong with that. In everything we've done, there is always someone willing to lead the way, and others that will follow. And the range anxiety is not really applicable to a bus. In fact you could say this is really the perfect use case for an EV.
- Karunamon 4y agoLithium batteries are dangerous in a way gasoline tanks are not: while a punctured tank (say, due to a unlucky collision with a piece of debris or a crash) is dangerous, it does not guarantee a fire or explosion. A punctured lithium cell will almost always burn. There are also more ways to screw up a battery. Overcharging, manufacturing defects, and so forth. A gas tank is literally a chunk of cast metal with a pump in it. Additionally, metal fires are severely hard to fight. Gas fires can be extinguished in the usual ways, but a self-oxidizing metal fire require special considerations, and that's if it can be reasonably extinguished at all. That isn't even mentioning the need to de–energize the battery before attempting a rescue.
- philipkglass 4y agoPrimary (non-rechargeable) lithium batteries contain metallic lithium, but all lithium ion batteries in vehicles contain lithium only in ionic form. Building rechargeable lithium batteries with lithium metal anodes is still in the research stage. The problem with fighting lithium ion vehicle fires is heat from battery self-discharge which can cause ignition and re-ignition of the flammable liquid electrolytes inside the batteries. That's one reason researchers are also pursuing solid state lithium ion batteries: to take out the flammable liquid electrolytes that current batteries need.
- dangle1 4y agoThe make of the bus doesn't seem to have been reported, but maybe one of the New Flyers they purchased? https://portal.ct.gov/DOT/Publictrans/Bureau-of-Public-Transportation/Battery-Electric-Bus-Projects-and-Partners https://portal.ct.gov/DOT/Publictrans/Bureau-of-Public-Trans...
- ShakataGaNai 4y agoWhile this is unfortunate to have happened, this says more about CT being smart and having an over abundance of caution, than lack of faith in a technology. BART, which has been running for 50 years recently [1] had an issue with the heat that caused a train to derail. For several days that section of track was totally shut down. For weeks afterwards they ran the trains at an extremely low speed through the miles of surrounding track - for safety. It's been a month and I'm honestly not sure if they are running "at speed" again yet. It's good to be cautious when you don't know the cause of an issue or aren't sure what happened. Someone could have shot the bus's battery... or it could be wired in a faulty manner... or they could have a design flaw. Lots of options, good to ground them until you know why. Lest we have another MAX8 debacle. [1] https://www.eastbaytimes.com/2022/06/21/bart-train-partially-derails-causing-minor-injuries/ https://www.eastbaytimes.com/2022/06/21/bart-train-partially...
- starkd 4y agoYes. Good thing to ground them, but it also shows these vehicles are not ready. Even if its an act of sabotoge, like someone shooting at the battery. It would not happen with a regular diesel bus.
- velcrohacker 4y agoUmm, it did. In CT. Last month. https://archive.ph/FZ2wv https://archive.ph/FZ2wv
- ceeplusplus 4y agoI think the difference here is that an EV battery fire quickly spreads to the entire length of the bus, because the battery spans the entire length of the bus internally. Whereas the diesel fire is contained to the fuel tank and engine block, which could allow passengers to more easily escape to whatever end of the bus isn't on fire. New battery chemistries like LFP should solve the thermal runaway issue.
- 4y ago
- billyo 4y agoWe need more electric trolley busses. This whole battery nonsense is ridiculous
- sleepybrett 4y agoSeattle has a great many of them but the lines for them to run on only exist in certain place, granted they are the densest places. But running that pair of electric lines everywhere is a big infrastructure project for any city.
- olyjohn 4y agoThey're willing to tear up the streets, install rails and run those slow-ass streetcars down the middle of the road. Also I imagine that getting enough power to your charging facility to charge 50+ buses up overnight isn't going to be any small feat either. At least with the overhead lines, you don't have to worry about charging. You don't have to carry heavy, expensive batteries either. Though you do get the occasional "derailment" where the bus comes off the line. But the bus drivers are able to fix that themselves.
- tapoxi 4y agoBostonian here, I used to commute on one every day (MBTA 71 and 73), but they were taken out of service earlier this year, for eventual EV replacement. The problem with electric trolley busses is that they can't pass each other, they perform very poorly in rain, frequently disconnect, and they need constant maintenance of the overhead wiring. I do miss it because it was a local landmark, but an EV bus will be much nicer to have.
- thescriptkiddie 4y agoTrolley busses can overtake each other, either by having a passing loop built in to the overhead wires or by briefly dewiring and rewiring the bus. Modern trolley busses can travel short distances off-wire and some can even rewire themselves automatically. The only reason MBTA has had so many problems with unintended dewiring is that they have done little to no maintenance on the overhead wires for the last half century. You can expect that the same will happen sooner or later to whatever charging infrastructure they build for battery electric busses. That is, assuming that they even that far and don't just pull a bait-and-switch as soon as the wires are down.
- billyo 4y agoWe need more electric trolley busses. These battery powered ones are nonsense
- akgerber 4y agoModern trolleybuses with in-motion charging, like Dayton's latest models, will still have substantial batteries for off-wire operation.
- KennyBlanken 4y agoTrolley buses cannot be detoured and the infrastructure costs are enormous, as is the cost of even a minor route change. Battery technology continues to improve in cost, energy density, and charge/discharge rate. There are already systems that use a catenary-like device to "top off" the bus while it is stopped at a bus stop.
- sofixa 4y agoAll modern trolleybuses have either batteries or diesel engines for detours. Infrastructure costs aren't "enormous", that would be if you're putting rails in the ground for trams.
- jeffbee 4y agoBattery buses are a solution ahead of their time. Any old bus is better than car-based transportation, so shifting modes from car to bus is more important than changing the energy source of the bus. If shifting from car to bus is impossible because of built environment, that's the first priority. Buses powered by batteries should be way down at the end of the TODO list. If you absolutely insist on having buses that aren't direct sources of CO2, fuel cells are a more mature technology that makes more sense than batteries.
- txsoftwaredev 4y agoA bus is only better if it is full of passengers, which is not always the case.
- dumpsterlid 4y agoYah precisely the point. We should focus on making busses comfy and nice and on getting good coverage with bus routes so that people use them. Worry about them being electric later, the environmental impact of less people driving far overshadows the impact of ev vs gas busses.
- pineconebutt 4y ago
- absolutelynobo 4y agoThe stunning failure of Nikola or any other large-scale fuel cell company other than Toyota to deliver working FC vehicles really calls into question your characterization of hydrogen as “more mature” than batteries. Every FC vehicle is also an EV, just FYI. One would also wonder why China has ~0 fuel cell buses and tens of thousands of electric buses if FC is the more mature tech.
- jeffbee 4y agoMy city has a large fleet of fuel cell buses and has had them for over a decade, which suggests you don’t know what you are talking about.
- mikeytown2 4y agoLithium-titanate battery Seems like a better fit for in city transportation where a quick charge is possible and safety is highly desired. Not to mention the lifetime of those cells. Lithium Nickel Manganese Cobalt Oxide (NMC) Batteries have higher energy but very short lifespans and are extremely flammable in comparison. https://en.wikipedia.org/wiki/Lithium-titanate_battery https://en.wikipedia.org/wiki/Lithium-titanate_battery
- drooby 4y ago> As a result of the fire, the electric bus fleet was pulled from service as a precaution, Rickman said. > “The importance of rider safety is demonstrated by taking these buses out of service and ensuring a thorough investigation is completed prior to any redeployment of the fleet,” Rickman said.
- novantadue 4y agoThis happened in China as well with a domino effect: 5 buses total https://newsasiatoday.com/electric-bus-china-caught-fire/ https://newsasiatoday.com/electric-bus-china-caught-fire/
- throwaway1777 4y agoHow much emissions did that release compared to running a petrol bus?
- MafellUser 4y agoSimilar to a burning petrol bus.
- chernevik 4y agoWhich happens how often?
- MichaelCollins 4y agoI haven't heard of petrol buses before, you probably mean diesel or CNG. Petrol is what Americans and Canadians commonly call gasoline, which is generally used in smaller vehicles than buses or trucks, which generally burn diesel instead. Petrol is a lot more dangerous than diesel because petrol fumes are explosively flammable, while diesel is relatively nonvolatile.
- woodruffw 4y agoI think it's fantastic that smaller-to-midsized towns are bringing EV buses into service, but I'll mention my perennial bugbear again: all of these towns had dedicated trolley service under a century ago. The lines were torn up and replaced with less frequent, traffic encumbered bus routes. Hamden, for example, had three lines between it and New Haven[1]. [1]: http://www.hamdenhistoricalsociety.org/trolleys.html http://www.hamdenhistoricalsociety.org/trolleys.html
- jdlshore 4y agoI get that this bugs you, but what does it add to the conversation today? Those lines are long gone, and it's not like complaining about it will bring them back.
- dangerwill 4y agoThese lines would be unambiguously better (cheaper, much simpler materials, much less embodied carbon, faster and more reliable if given a proper right of way) than a bunch of electric buses in shared traffic so it makes sense to bring them up.
- googlryas 4y agoNot really, because you can rework bus routes about 10,000x easier than rerouting trolley lines. If there are very dense, well defined lines, then sure trolleys can be better.
- dangerwill 4y agoAnd yet bus routes don't change that often. Let's say it would take 10 years to change a trolley path (an insane time frame but it's the usa so...), I don't see any bus routes changing 3x a day. It is easier to reroute but the difference is only really like 2-5x. And with the trolley you can actually be confident of it showing up on time :)
- mminer237 4y ago
- chernevik 4y ago> "they emit no emissions and they last longer" Not when they spontaneously combust they don't
- SigmundA 4y agoAnyone know the brand of bus and type of battery pack? Can't seem to find the info. Mainly wondering if it is a NMC or NCA pack or more stable LFP pack. LFP's are much safer with much lower chance for thermal runaway but they will still burn, they are also cheaper have much long cycle life and don't use nickel or cobalt but have a lower energy density. City buses would be a great application for LFP.
- tantar 4y agoIm a Vol Firefighter in a Major City Suburb with lots of highways and tons of crashes. We get 2-3 car fires and passenger extractions per month. The first question we ask on the way out is "Is this an EV?" We need to know this because EVs trigger the rollout of Water Tankers from surrounding towns, as many as we can get. Usually a Water Shuttle has to be set up. Not many Fire Hydrants on Highways, and EV fires require A LOT of water, like several house fires worth... Here is some external detail on this - https://www.businessinsider.com/tesla-crash-fire-lithium-battery-austin-more-water-than-regular-2021-8 https://www.businessinsider.com/tesla-crash-fire-lithium-bat... Also, we need to start calling more manpower. EV fires burn a very very long time while ICE fires are usually put out in the first few mins, and with 1 engine's 1000gal tank water. Adding to this, the fire is usually under the car, and quite hard to get too. We are very good at opening locked car hoods and cutting metal to get at the fire, but when its deep in the guts of the thing, its impossible. At my department, we have started working on ways to jack the car up safely while its on fire so we can get water onto it. Trust me, its even harder than you would think... The Standard Operating Procedure is to put water on the car and surrounding area so that nothing else catches on fire, but basically we have to let the thing burn out, and that can take hours and hours... EV car batteries do not rely on the environment for their fires to burn. The fuel brings its own oxidizer, and it doesnt need anything else. We can put out Liquid Fuel fires by robbing the oxygen or removing the heat(thats what the water does), but once EV fire gets to a particular point of no return (which it arrives at very quickly) there is really nothing that can be done to stop it, just make sure it doesnt get any worse... Here is the current thinking from the NFPA (firefighting safety and standards organization in the US), you'll see EV car fires are long on problems, but even the most focused minds in the US Fire Prevention industry are short on answers at this time. https://www.youtube.com/watch?v=Sp3WvKON_W4 https://www.youtube.com/watch?v=Sp3WvKON_W4
- beams_of_light 4y agoI recently purchased an EV, and there is an emergency high voltage battery cutoff in the rear. Do you guys know about those, or if so, are they effective?
- 4y ago
- weq 4y agoLION batteries are insane - to see what happens at serach for this on youtube. There are mass graveyards of e-bikes after battery suppliers where rebadging low quality cells are higher ones leading to a generation of lottery tickets. Something like 5 fires a day for e-bike, not sure of the stats on cars. https://www.youtube.com/watch?v=el_hNwaUSfU&t=3s https://www.youtube.com/watch?v=el_hNwaUSfU&t=3s