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> I’m aware of the safety benefits inherent in the skateboard-battery chassis design but that doesn’t account for all of the safety accolades they’ve received.

> I’m aware of the safety benefits inherent in the skateboard-battery chassis design but that doesn’t account for all of the safety accolades they’ve received. Why aren’t the other automakers doing as well in the NHTSA tests as Tesla? Factor #1 is the battery. It's far and above the biggest safety feature. Factor #2 is that nobody else makes electric cars as big as Tesla. The Model 3 is 9" longer than a Leaf and a full 21" longer than a Bolt. That means WAY more crumple zone -the crumple zone is the first thing to go in a small car, making room for legs- and that's the biggest safety difference between cars. I think you're also underestimating the impact of the battery. The center of mass makes it practically impossible to roll, a huge source of injuries and deaths. It's also incredibly resistant to pole and many vehicle intrusions, since those happen either on or just above the battery, which is extremely strong compared to normal cars. The battery also lets almost the entire front and back of a Tesla be used as a crumple zone. Nobody else is really doing this. The Bolt has the second best battery among EVs for sale currently, and it's still shaped and positioned pretty much like a gas tank. It blocks a lot of crumple zone. The engine in any normal car is totally incompressible and massively limits the crumpling- worse, the higher end, larger cars will still have correspondingly larger engines, limiting safety. They might have a foot or two of crumple distance, while the entire hood of a Tesla can absorb impact. Even the motor can snap up and back if needed. In a Tesla, you automatically combine 3x the shock absorption with an extremely strong safety cell and the strongest anti-rollover feature of any car. It's zero surprise they do incredibly well in crash tests.

lifeisstillgood 8y ago
Ben Evans is good on the issues of "Does tesla have a real moat, or are they just first, and so will get steamrollered by incumbents when they catch up." He posits the question that what is it Tesla does differently that might be a moat - and your answer to the question indicates they might just have something So Evan's main argument seems to be, Tesla is a bit like Apple in that they make a highly restricted set of products, but all their component parts are hyper-specific to the product, meaning they go to town on integration - there are no factory line compromises to be made between product X and a batch of a thousand product Y tomorrow. Your answer suggests that using an existing factory line to build your electric cars seems a good idea, but then all you can do is replace the space where the fuel tank goes with the space where the battery goes. That means they lose out on a "free" safety upgrade of putting the battery in the middle of the car. So Tesla's approach - can it be mimicked by incumbents - sure - by those willing to throw away their existing factory capital and reinvest. And it does make the idea of "the org chart of the car company is seen in its dashboard" as even more important - if the ideal position of the battery is compromised by the current factory investment, what else in the way car companies are organised is sub-optimal in a new world?
- hef19898 8y ago
  You fail to realize two things. 1) car compabies are retooling already every couple of years with each model change. They are good at that, that's what they do. Due to scale it seems that it takes longer, but given the headaches Tesla had with the Model 3 the effect is not as big. 2) EV are actually a lot easier to build than ICE powered cars. So the only thing that held incumbents back was low expectations on the sales volume. And that is changing. This also explains to large degree the momentum these compabies have once the move. And don't even talk about first time pass yield for the Model 3 compared to other companies out there. EDIT: Typos
  - ericb 8y ago
    How does the sales organization at your dealer sell the model of the future without trash-talking all the other gas-guzzling vehicles in the lot? How do you convince a dealer dependent on the revenue from servicing those engines to go against their self interest and sell something without that revenue stream?
    - gameswithgo 8y ago
      sales people have no problem with cognitive dissonance, they do it all day for thousands of years now.
      - woodandsteel 8y ago
        The question is not their ethics, it is whether their bosses would let them do it.
    - scoggs 8y ago
      I agree with your line of thinking. They are absolutely married to that ball-and-chain for whatever amount of time it takes them to go all out. It seems like the thing that helped American auto makers "bounce back" after things went extremely south before 2010 is also their biggest Achilles heel outside of being inherently gas-based vehicles: their choice to create entire lines of cars that's profitability hinged on the interchangeability and cross-model compatible frames and parts is also the reason they can't simply "re-tool" or redesign any of their models without completely scrapping the ideas and starting from scratch. In a sense I almost feel like if these car companies decide to do as much they may have to entirely scrap previous car models and start anew. Imagine Ford saying goodbye to the F-150 / general truck models, the Mustangs, the Explorers. Chevy and Dodge saying goodbye to the cars and trucks they are able to sell to law enforcement, military, and government. I really can't. Maybe I'm oversimplifying things but from my outside, rookie POV it seems like these are huge reasons due to the fact that their entire manufacturing supply line is reliant on this model that's helped them all but die off in competition to foreign auto makers.
_ph_ 8y ago
Yes, like with many disciplines of engineering, starting with the right approach is a large part of designing a good product. Here it is with starting as an electric car with a battery skateboard. The rest then is competent engineering the structural parts around the battery and the crumple zones. And it is no surprise that the engineering at Tesla is competent. After all, Tesla does have a good contact to SpaceX, where actual rocket scientists work :). In any case, SpaceX is a great source of expert knowledge on material science and structural strength.
cpsempek 8y ago
You’re absolutely correct about the battery acting as a structural member. Another important safety plus is the removal of the engine. You now have the frunk acting as a large crumple zone and no chunk of metal shoving a steering column into the driver. But the battery indeed provides a lot of support to the pillars during side collisions. edit. It's been pointed out that the steering column has not been a safety issue for decades. However, I suppose the point remains about the added safety of lacking an engine, that is not having a block of metal ready to apply a large force in the drivers direction during a head on collision. But I'm happy to be corrected on this point too.
- dsfyu404ed 8y ago
  > and no chunk of metal shoving a steering column into the driver It's not 1960 anymore. We have collapsible columns and we no longer have steering gears mounted on the frame forward of the axle (we have racks mounted on or in the vicinity of the firewall). Steering column in the driver's face is a non-issue and has been for decades.
- FireBeyond 8y ago
  > you now have the frunk acting as a large crumple zone and no chunk of metal shoving a steering column into the driver. As a first responder who has responded to hundreds of MVAs, I have never seen nor heard of a steering column being shunted into a driver by the engine block. Perhaps in the 60s or earlier, but steering columns are designed to crumple.
- rconti 8y ago
  Collapsable steering columns have been a thing for decades, and while Tesla touts it, they certainly don't imply that they're the only ones with one. Traditional internal combustion engines have breakaway motor mounts these days, to allow the motor to detach from the chassis and drop down towards the roadway to minimize intrusion into the cabin, but having a motor crushed into your feet is only somewhat better than having it shoved into your lap, I suppose.
davidgould 8y ago
I think you are slightly unfair to the Bolt. Its battery is mainly in a skateboard like Teslas with some also under the rear seat [0]. So unless they really messed up the structure it should have the same advantages as the Tesla battery location. That said, the front compartment is a big messy jumble of boxy components. This may not impact(!) safety much, but does show how far GM is from the level of integration Tesla attains. [0] http://gmauthority.com/blog/wp-content/gallery/2017-chevrolet-bolt-ev/2017-chevrolet-bolt-ev-powertrain-drive-unit-and-battery-008.jpg http://gmauthority.com/blog/wp-content/gallery/2017-chevrole...
- hwillis 8y ago
  Nah, the Bolt battery isn't nearly as structural. It increases chassis stiffness but has a low impact on safety. The reason is it's essentially hanging off chassis rails- Tesla batteries basically join to the chassis to form one big box. The bolt battery also has no internal ribs, just a couple pretensioning bolts (to prevent vibration). It's only slightly stronger than a gas tank in an impact. Tesla batteries have huge internal ribs/separators that make the battery very resistant to deformation and intrusion in an impact. The Tesla battery is also about 10% wider, which makes a HUGE difference. A side impact in the Bolt will be through your leg before it hits the battery. In the Tesla the battery will be hit around the same time you are, making it an extremely integrated part of the safety cell. Its much more complex to build this way, since theres no undercarriage to route things through.
King-Aaron 8y ago
> The engine in any normal car is totally incompressible This is just an interesting aside note, but my mother was recently involved in a frontal collision while driving her 2016 hyundai i30. In what was approximately a 60-70 kph impact with another car, it was enough to shatter the aluminium engine block in several places, and the engine sort of crushed flat. I'd never seen a block do that before, at least not in a relatively low speed collision. Wish I'd taken some photos of it. But it made me wonder if modern cylinder block design incorporates any failure points in their design for such a scenario... Of course maybe it could have just come down to the randomness of crash dynamics.
Latteland 8y ago
the bolt should be a great crash safety car too then, although it is apparently much shorter than a m3.

lifeisstillgood 8y ago

Ben Evans is good on the issues of "Does tesla have a real moat, or are they just first, and so will get steamrollered by incumbents when they catch up." He posits the question that what is it Tesla does differently that might be a moat - and your answer to the question indicates they might just have something So Evan's main argument seems to be, Tesla is a bit like Apple in that they make a highly restricted set of products, but all their component parts are hyper-specific to the product, meaning they go to town on integration - there are no factory line compromises to be made between product X and a batch of a thousand product Y tomorrow. Your answer suggests that using an existing factory line to build your electric cars seems a good idea, but then all you can do is replace the space where the fuel tank goes with the space where the battery goes. That means they lose out on a "free" safety upgrade of putting the battery in the middle of the car. So Tesla's approach - can it be mimicked by incumbents - sure - by those willing to throw away their existing factory capital and reinvest. And it does make the idea of "the org chart of the car company is seen in its dashboard" as even more important - if the ideal position of the battery is compromised by the current factory investment, what else in the way car companies are organised is sub-optimal in a new world?

hef19898 8y ago
You fail to realize two things. 1) car compabies are retooling already every couple of years with each model change. They are good at that, that's what they do. Due to scale it seems that it takes longer, but given the headaches Tesla had with the Model 3 the effect is not as big. 2) EV are actually a lot easier to build than ICE powered cars. So the only thing that held incumbents back was low expectations on the sales volume. And that is changing. This also explains to large degree the momentum these compabies have once the move. And don't even talk about first time pass yield for the Model 3 compared to other companies out there. EDIT: Typos
- ericb 8y ago
  How does the sales organization at your dealer sell the model of the future without trash-talking all the other gas-guzzling vehicles in the lot? How do you convince a dealer dependent on the revenue from servicing those engines to go against their self interest and sell something without that revenue stream?
  - gameswithgo 8y ago
    sales people have no problem with cognitive dissonance, they do it all day for thousands of years now.
    - woodandsteel 8y ago
      The question is not their ethics, it is whether their bosses would let them do it.
  - scoggs 8y ago
    I agree with your line of thinking. They are absolutely married to that ball-and-chain for whatever amount of time it takes them to go all out. It seems like the thing that helped American auto makers "bounce back" after things went extremely south before 2010 is also their biggest Achilles heel outside of being inherently gas-based vehicles: their choice to create entire lines of cars that's profitability hinged on the interchangeability and cross-model compatible frames and parts is also the reason they can't simply "re-tool" or redesign any of their models without completely scrapping the ideas and starting from scratch. In a sense I almost feel like if these car companies decide to do as much they may have to entirely scrap previous car models and start anew. Imagine Ford saying goodbye to the F-150 / general truck models, the Mustangs, the Explorers. Chevy and Dodge saying goodbye to the cars and trucks they are able to sell to law enforcement, military, and government. I really can't. Maybe I'm oversimplifying things but from my outside, rookie POV it seems like these are huge reasons due to the fact that their entire manufacturing supply line is reliant on this model that's helped them all but die off in competition to foreign auto makers.

_ph_ 8y ago

Yes, like with many disciplines of engineering, starting with the right approach is a large part of designing a good product. Here it is with starting as an electric car with a battery skateboard. The rest then is competent engineering the structural parts around the battery and the crumple zones. And it is no surprise that the engineering at Tesla is competent. After all, Tesla does have a good contact to SpaceX, where actual rocket scientists work :). In any case, SpaceX is a great source of expert knowledge on material science and structural strength.

cpsempek 8y ago

You’re absolutely correct about the battery acting as a structural member. Another important safety plus is the removal of the engine. You now have the frunk acting as a large crumple zone and no chunk of metal shoving a steering column into the driver. But the battery indeed provides a lot of support to the pillars during side collisions. edit. It's been pointed out that the steering column has not been a safety issue for decades. However, I suppose the point remains about the added safety of lacking an engine, that is not having a block of metal ready to apply a large force in the drivers direction during a head on collision. But I'm happy to be corrected on this point too.

dsfyu404ed 8y ago
> and no chunk of metal shoving a steering column into the driver It's not 1960 anymore. We have collapsible columns and we no longer have steering gears mounted on the frame forward of the axle (we have racks mounted on or in the vicinity of the firewall). Steering column in the driver's face is a non-issue and has been for decades.
FireBeyond 8y ago
> you now have the frunk acting as a large crumple zone and no chunk of metal shoving a steering column into the driver. As a first responder who has responded to hundreds of MVAs, I have never seen nor heard of a steering column being shunted into a driver by the engine block. Perhaps in the 60s or earlier, but steering columns are designed to crumple.
rconti 8y ago
Collapsable steering columns have been a thing for decades, and while Tesla touts it, they certainly don't imply that they're the only ones with one. Traditional internal combustion engines have breakaway motor mounts these days, to allow the motor to detach from the chassis and drop down towards the roadway to minimize intrusion into the cabin, but having a motor crushed into your feet is only somewhat better than having it shoved into your lap, I suppose.

davidgould 8y ago

I think you are slightly unfair to the Bolt. Its battery is mainly in a skateboard like Teslas with some also under the rear seat [0]. So unless they really messed up the structure it should have the same advantages as the Tesla battery location. That said, the front compartment is a big messy jumble of boxy components. This may not impact(!) safety much, but does show how far GM is from the level of integration Tesla attains. [0] http://gmauthority.com/blog/wp-content/gallery/2017-chevrolet-bolt-ev/2017-chevrolet-bolt-ev-powertrain-drive-unit-and-battery-008.jpg http://gmauthority.com/blog/wp-content/gallery/2017-chevrole...

hwillis 8y ago
Nah, the Bolt battery isn't nearly as structural. It increases chassis stiffness but has a low impact on safety. The reason is it's essentially hanging off chassis rails- Tesla batteries basically join to the chassis to form one big box. The bolt battery also has no internal ribs, just a couple pretensioning bolts (to prevent vibration). It's only slightly stronger than a gas tank in an impact. Tesla batteries have huge internal ribs/separators that make the battery very resistant to deformation and intrusion in an impact. The Tesla battery is also about 10% wider, which makes a HUGE difference. A side impact in the Bolt will be through your leg before it hits the battery. In the Tesla the battery will be hit around the same time you are, making it an extremely integrated part of the safety cell. Its much more complex to build this way, since theres no undercarriage to route things through.

King-Aaron 8y ago

> The engine in any normal car is totally incompressible This is just an interesting aside note, but my mother was recently involved in a frontal collision while driving her 2016 hyundai i30. In what was approximately a 60-70 kph impact with another car, it was enough to shatter the aluminium engine block in several places, and the engine sort of crushed flat. I'd never seen a block do that before, at least not in a relatively low speed collision. Wish I'd taken some photos of it. But it made me wonder if modern cylinder block design incorporates any failure points in their design for such a scenario... Of course maybe it could have just come down to the randomness of crash dynamics.

Latteland 8y ago

the bolt should be a great crash safety car too then, although it is apparently much shorter than a m3.