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Carmakers want to ditch battery packs, use auto bodies for energy storage
- killingtime74 6y agoI want to have wings and fly on a jetpack
- kenperkins 6y agoNo they don't. Researchers propose they (the carmakers) do. I can't even imagine the maintenance or repair considerations of a pack that's embedded inside of the frame or a monocoque chassis. Lastly this isn't even an Ars article, it's from Wired. It really is a terrible click-bait headline. The article, imho isn't much better.
- toomuchtodo 6y agoTesla is moving to this architecture. https://cleantechnica.com/2020/10/10/teslas-new-structural-battery-pack-its-not-cell-to-pack-its-cell-to-body/ https://cleantechnica.com/2020/10/10/teslas-new-structural-b... (Tesla’s New Structural Battery Pack — It’s Not Cell-to-Pack, It’s Cell-to-Body)
- deleted 6y ago[deleted]
- freshpots 6y agoNot quite. You should read the article as they call out Tesla in particular for not doing so.
- Qwertious 6y agoNo they aren't. Normally you have battery cells (think AAs) -> battery pack -> vehicle trunk, and they're skipping the middle step. It's analogous to how planes have a "wing-shaped fuel tank" (where the wings just have a cavity that you pour the fuel into), instead of storing fuel fluid containers that are separate to the plane. What OP's link is describing, is where the battery cells literally are the vehicle trunk - as in they're built into the walls, instead of being contained between two walls.
- phkahler 6y agoIt's also important for cells in a pack to have the same size. Making a bunch of arbitrary sized body parts would to the opposite.
- marshray 6y agoWell, the cells don't need to be the same size if they each have their own charge controller.
- ethbr0 6y agoStressed skin [0,1] is great for saving weight and enhancing rigidity. It's terrible for repairability, and with regards to power sources... safety. This is a bunch of researchers solving the wrong optimization problem. You'll likely see it in Formula E, but under no circumstances should it be in production, mass-produced cars. [0] https://en.m.wikipedia.org/wiki/Lotus_25 https://en.m.wikipedia.org/wiki/Lotus_25 [1] https://en.m.wikipedia.org/wiki/McLaren_MP4/1 https://en.m.wikipedia.org/wiki/McLaren_MP4/1
- colinmcdermott 6y ago> Lastly this isn't even an Ars article Gizmodo stylee
- jjulius 6y ago> No they don't. Researchers propose they (the carmakers) do. Yes they do. The first paragraph of this article discusses Elon Musk talking about integrating this into Teslas.
- RcouF1uZ4gsC 6y agoA big issue with this would be safety. You don’t want your car to explode if someone runs opens their door into the side of your car. Also, repair costs would be crazy. You probably could not bang out dents, but would have to replace the entire (very expensive) structural battery quarter panel.
- beagle3 6y agoUnfortunately, having to replace a big part at a huge cost (instead of banging) is a great incentive for car makers to go this way.
- csharptwdec19 6y agoCalling it now, it will be used to fuel the push towards forcing 'self driving' cars at some point in the name of safety/cost to drivers. This benefits the Car manufacturers of course, since Self-driving cars will almost certainly require a 'Subscription' plan
- brianwawok 6y agoTesla batteries do not extend to the edge of the frame. There is a buffer for t-bones and side impacts. Thousands of crashes and 8 years in your odds of bursting into flames seem lower in an EV than an ICE car with a tank of gas.
- evgen 6y agoYou do realize that real life is not a Hollywood movie, right? Cars do not explode like you see on TV. The crash danger to be concerned about is not that the car will burst into flames, but rather that when you wrap your car around a tree the rescue crew will be unable to extract you due to electrocution risk and so you will slowly bleed out while they wait for specialists with the right EV extraction experience to arrive. This was a major problem when the Prius hit the scene and suddenly there were high voltage cables that needed to be avoided, but if a crash could possibly electrify body panels or other more exposed pieces then things may get dangerous.
- gwbas1c 6y agoWhat happens in an accident, or when someone drills a hole through the frame?
- ssully 6y agoI think if this becomes a reality, the standard advice will be: "Do not drill holes through your car frame"
- macjohnmcc 6y agoWe can adapt the don't drill a hole in anything that may contain flammable liquid to include don't drill into anything energized.
- VBprogrammer 6y agoPretty decent advice even without the chance of drilling through the battery pack.
- throwaway0a5e 6y ago"pay $599.99/mo for this upfitter guide subscription that tells you where to drill"
- LeifCarrotson 6y agoIt's much like unibody car repair: You used to be able to bolt a hitch, bumper, roll cage, or winch to the ladder frame of your vehicle. The ladder frame was basically a pair of ~2x5" C-channel heavy steel bars running the length of the vehicle, with crossmembers linking them together. It's still present on a lot of trucks, and some SUVs, but more and more vehicles are moving towards lighter unibody construction. In particular, this helps with impact safety, because the unibody can form crumple zones. A ladder frame doesn't crumple. Now, most vehicles don't have ladder frames. If you want to drill a hole for attaching a bolt, for example to add a tow hook, you probably need to first weld on a 1/4" plate. A body shop can't just un-bolt a rocker panel damaged in an accident and put on new ones, both rocker panels are one big piece that forms part of the structure of the vehicle and everything else is connected to them. You cut and weld to repair the damage, or bend it back into place. In race vehicles and motorcycles, this concept is extended to the engine itself: The block is a structural member of the vehicle. Practice will adjust to progress. It won't always be as easy to repair as it once was. We can only hope that the safety and energy improvements are worth the complexity and functionality.
- wongarsu 6y agoPassenger cars all moved from a body-on-frame structure to a more integrated unibody construction where a lot of the rigidity is provided by other parts that happen to be located on the underside of the car. In an electric car that has a battery on the underside, delegating some of that structural integrity to the fairly rigid battery pack seems like an obvious extension of that trend. I'm pretty sure that's what Musk means when he talks about structural batteries. That will probably mean some changes to the battery packs to make them more fit for that purpose (that could mean changes to the cells, but doesn't have to) Integrating battery packs anywhere else in the body of the car seems much less practical. These car batteries aren't like notebook batteries: they have dedicated heating and cooling systems in addition to high current connectors, fire proof casings, emergency shutoffs etc. You can't just pepper those around the car.
- hinkley 6y agoWhat do they mean by Musk is incorporating the batteries into the frame? They just introduced a larger cylindrical cell. Cylindrical cells don’t get embedded, unless you mean as in a flashlight. In some other generation of battery tech, there’s plenty of gray area here that still provides benefit. A stiffer battery requires less housing. A stiff enough battery only requires shielding against punctures. Stronger still, and you can bolt it between two frame elements and have it function like a cross brace, while still being able to remove it for servicing.
- 0_____0 6y agoI watched their battery PR presentation and it seems like they're trying to integrate the structure of the battery (maybe not the individual cells but I'm unclear on this) as a "stressed member" so to speak, same way that the engine in a motorcycle is often a critical structural component. Makes sense, because the battery is super heavy and needs a ton of stucture itself, might as well integrate it more with the frame and reduce redundancy.
- hinkley 6y agoIt sounds like as well they’ve reduced the length of the pack, allowing for larger crumple zones, which is a definite improvement, notwithstanding any other pluses.
- kevan 6y ago>[Musk] hailed Tesla’s structural battery as a “revolution” in engineering—but for some battery researchers, Musk’s future looked a lot like the past. >“He’s essentially doing something that we did 10 years ago,” says Emile Greenhalgh, a materials scientist at Imperial College London Doing something under research conditions and doing it in a mass-produced commercial product are separate accomplishments. Both are important and impressive and should be celebrated.
- throwaway894345 6y ago> mass-produced commercial product To add to that, in a domain with life or death consequences.
- Animats 6y agoRemember how Tesla had to add a titanium skid plate to prevent battery fires caused by punctures from running over road debris? Batteries in body parts likely to be damaged in collisions would be a problem. Also, having the heavy battery down below axle height makes for a nice low center of gravity, making the vehicle much more stable.
- KMnO4 6y agoThat’s definitely true, but battery technology has advanced quite a bit. Cells can take a bigger beating without issue compared to early Tesla’s.
- cellular 6y agoJust connect the airbag sensor to a resiStor load to dump the charge upon an impact. Pretty simple really.
- Animats 6y agoEr, no. Dumping 75KWH as heat requires a big resistor bank. One of these[1] could dissipate the power from a fully charged Tesla battery in 45 minutes. That's probably about as fast as you could discharge one without it catching fire. And you'd need the battery cooling system working. [1] http://sikes-elec.com/Resistive-load-bank-450VDC-750VDC-100KW.html http://sikes-elec.com/Resistive-load-bank-450VDC-750VDC-100K...
- mschuster91 6y agoInteresting concept but I guess there will be huge investments needed into material science - we can model how a metal or carbon composite frame will react when exposed to impacts or general mechanical stress, how much load a given part can bear under which circumstances after many decades of data gathering, but for a battery that is the structure we don't have experience.
- g42gregory 6y agoI would like to understand what happens when you are in the accident? Does this increase the risk of fire/explosions no matter where you get hit? I still remember driving by the burnt-out Tesla on 101 & 95 intersection.
- gnicholas 6y agoOut of curiosity, where does 101 cross 95? I thought these ran north-south.
- timbit42 6y agoPerhaps in New Hampshire? https://www.google.ca/maps/place/NH-101A,+Milford,+NH,+USA/@42.9554707,-70.8568582,14.5z/data=!4m5!3m4!1s0x89e3c9e11cf9fc89:0x8c6745092afc0a8f!8m2!3d42.8352818!4d-71.6545208 https://www.google.ca/maps/place/NH-101A,+Milford,+NH,+USA/@...
- jcranmer 6y agoI was going to say it's probably CA state route 95, but I looked it up and found there actually isn't a CA state route 95. US 101 & CA 92 and US 101 & CA 85 are plausible intersections if OP wrote a typo.
- toast0 6y agoThe junction of US 101 and CA 85 is the location of a well publicized Tesla fatality (tldr Apple employee in driver's seat, Autopilot engaged, vehicle accelerated into gore point, battery pack caught fire on scene and again later)
- g42gregory 6y agoSorry for the typo. It was US 101 and CA 85. Thank you for correcting this!
- crazyjncsu 6y agoThe news to me is now arstechnica.com is syndicating content from wired.com ... And as far as I'm concerned, no good can come from that... ... starting with this article which gives credence to these Asp and Greenhalgh fellows, who have deemed the current situation with batteries as a "structural parasite" while at the same time proposing to incorporate them into the skin of the vehicle, which moves mass way upwards and way outwards-- both of the no-nos in regards to stability. The negative effects from just the shifting of mass will likely outweigh any of the gains using their method, which so far seem to be a bit nebulous. And that's ignoring many of the obvious safety, reparability, and complexity concerns...
- toast0 6y agoWired and ArsTechnica are both Conde Nast brands. Wired is definitely 98% breathless reporting, and ArsTechnica is aiming for that too, while still trying to catch a couple people that remember what it was like before they sold out.
- backtoyoujim 6y agoI know that some container ships are using sails once again to help with fuel costs. It would be a neat triple play to have the sails be solar panels and the batteries, too.
- jessriedel 6y agoDoes this mean giving up on every being able to replace the battery pack if it's integrated into the frame? Tesla battery packs are only warrantied for 8 years, and after that you need to pay ~$7k to replace them. Are they developing new battery tech to make this time period longer?
- evanwolf 6y agoJust throw away the car when the batteries age out.
- Qwertious 6y ago"Tesla battery packs are only warrantied for 8 years, and after that you need to pay ~$7k to replace them." You don't need to pay ~$7k. That's about the full price of a new battery. The battery isn't dead, it just has a lower rating (likely over 80%). Even if that's absolutely unacceptable, it can be used to A) replace batteries that have hit 60% or some other lower standard for people who don't care about range as much, or B) act as a stationary battery. Considering that cars are currently driven an average of "13 500 miles per year" according to US stats, 8 years is a little over 100k miles. Tesla has already hit the "million kilometre battery" mark (so at least two thirds toward the "million mile battery"), so it's kind of absurd to say you'd have any serious need to replace it 1/6th through its spec lifetime. And now for a BONUS: in 8 years the price of batteries will drop, due to economies of scale if nothing else. So the replacement will be cheaper than your current battery was (hah, implying we all have EV batteries).
- jessriedel 6y ago> You don't need to pay ~$7k. Sorry, but it sounds like you're quibbling over whether this is $7k or $5k with trade-in value. That doesn't address the substance of my comment.
- leeoniya 6y ago> Its battery pack will be integrated into the chassis so that it provides mechanical support in addition to energy, a design that Musk claimed will reduce the car’s weight by 10 percent and improve its mileage by even more. i wonder if it also reduces the possibility (or increases the cost) of recycling used battery packs by 80%.
- pengaru 6y agoThe only reason EVs don't handle like complete ass despite being relatively heavy is all the weight is concentrated in the floor with a skateboard battery pack design. This is stupid on multiple levels.
- evanwolf 6y agoSustainability? Can these new carbodybatteries be recycled when they can't take a charge? Can I replaces some of the car for a complete charge? or do I have to ditch the whole thing when the first component fails?
- JoeAltmaier 6y agoHm. Inevitably that would raise the center of mass, right? The Tesla battery is currently the floor of the vehicle I think. Now it'll be threaded through the body, which brings weight upward. It'll have to be done carefully, to keep it handling well.
- Qwertious 6y agoAre you supposed to flag for misleading titles? This isn't "carmakers", it's random material scientists.
- jmcguckin 6y agoExplosive skin on a vehicle... The military name for this is ‘reactive armor’. Imagine backing into a quarter panel in a parking lot - Boom!
- fattybob 6y agoreminds me of a scene in some TV show long ago where (Howard Hughes perhaps??) the character threw a hammer I tothe side of his steam car, where it gushed steam, and announced that he was no longer in the steam car business. I would not want to be inside a vehicle whose body panels were filled with something like lithium!! a sealed box underneath is acceptable if it passes crash tests, door panels, no way.