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Ancients cloud: Toyota native out of electric, family sacrifice without forgetting to tell Naiwong.
For many years, Toyota, which has been sneered at 10,086 times around the world for not having an electric car, finally came up with the first pure electric platform, the bZ4X, at the end of last year. Unlike previous "general-purpose platform" models such as the C-HR EV, Toyota has launched a new, native bZ pure electric platform on the bZ4X.
Such a Toyota tram that can be calculated by thousands of calls, the latest news is that the domestic listing is this year. The mass production version was only unveiled in November 2021, and the full set of processes from the off-line to the domestic release and then to the listing will be completed in 2022. This is not a chicken blood new car that came out of nowhere, this is a Japanese old stubborn with a steady word on the brain door.
When the bZ4X was released last year, all eyes were focused on the world's first pure-by-wire steering technology and the One Motion Grip steering wheel, which resembled Tesla's shape. We also used the entire length (see "This Time, Toyota Won Tesla") to explain the technical background of the bottom of the sci-fi steering wheel modeling as much as possible. Therefore, the steering wheel is no longer mentioned.
Why did the world's largest car company, which has always been known for its stability, take the lead in applying cutting-edge technology that has not been tested in time without warning?
When the bZ4X appeared on the scene with a steering wheel with a one-sided 150° full, full circle without changing hands, and like an airplane operating rudder, people seemed to have temporarily forgotten its important identity as "Toyota's first pure electric platform". Friends, you either support, or ridicule, or for its unfairness, or wait for its closure, countless hot search headlines repeat "Toyota does not have electric vehicles", in the end is not for this day, why was it a steering wheel hooked.
Pure electricity is not pure electricity, collinear is not collinear
According to the domestic listing in 2022, toyota's final native platform electric vehicle launch time will only be more than a year later than the overall more aggressive and advanced German opponents. This time difference is significantly smaller than the previous Toyota pure electric progress to give people the feeling and speculation.
The Volkswagen ID. series began to be listed and delivered in early 2021, but moving forward, in order to produce a new MEB pure electric platform including the ID. series (including Brands such as Audi), Volkswagen started construction of two new factories in Foshan and Anting as early as 2018, and a third Anhui MEB plant is under construction. Nearly three years later, the domestic ID. series began to be delivered.
Toyota, on the other hand, has actually started to build FAW Toyota's new energy plant in the Sino-Singapore Tianjin Eco-City since the beginning of 2020. The estimated production time naturally corresponds to the domestic launch time of the bZ4X, that is, within 2022. The whole rhythm cycle is comparable to the Volkswagen MEB program, and it takes about three years to work inside and out.
Anting MEB factory
Ben Hu once explained that today's "oil to electricity" and "native platform" are no longer as clear and clear as in the past, and the advantages and disadvantages are fully displayed. In short, whether the "pure electricity platform" is not for ordinary consumers, in fact, it all depends on the mouth of the car company. People are willing to call it whatever they want, and they don't break the law with a little bit of thought - who will be generous enough to tell you that they are "not designed for pure electricity"?
Think of it another way, manual Geng in their own backyard, according to the appearance of a fuel car Ctrl + C, Ctrl + V out of a pair of frames, and then only plug the battery without installing the internal combustion engine, he said that this is his own "pure electric platform" Problem? No, this is a pure electric platform for people, and people have never built even one oil car with it - some "new cars" don't sneeze when they hear it.
Therefore, "oil to electricity" or "native pure electricity", the name is a little girl dressed up, whether it is the name of the car company or the media statement is not absolutely reliable, reliable only your own judgment. The fundamental difference between the two is not "whether it has been used to build a fuel car", but "whether the 'benefits' of the fuel platform are thrown away for the optimal solution required by the electric vehicle".
Mercedes-Benz EVA platform, pure electric platform in the physical structure is completely different
What are the benefits of fuel base? Is a large proportion of parts can be universal, is to modify the design and adjustment of the rules to follow, the most important thing is to use the ready-made production line or only do part of the adjustment, work fast, save time and effort and save money. Don't forget that one of the most important roles in the birth of the "platform" is to realize the collinear production of different models of the same platform.
What the native pure electricity platform wants to represent is the broadest interest of the power class led by the battery, which is the battery life, the power consumption, the convenience of charging, and the absolute safety of the battery... Today's platform, to think about the basic appeal of electric vehicles, want to "electricity" think, anxious "pool" anxious, the result is naturally the physical existence level and fuel platform parting ways. You're square, I'm round, I'm sorry we can't do it.
So the new pure electric platform is always tied to a new factory or at least a new production line. You often see in the news how much and how much a certain brand has invested in the production of electric vehicles to build a new factory. On the same assembly line, you may be able to walk down the A4 and Q5 with front and back feet, but you can't produce the Q5 and Q5 e-tron at the same time. The more radical the transformation of pure electricity car companies, the more they will dig deeper into the "pit" of electric vehicle factories.
Less than a piece, or leave it
So how is the "physical existence" of pure electric platforms different?
In a narrow sense, the platform must be based on the body-in-white/frame as the carrier. At the beginning of the birth of the platform concept, its scope was mainly a part of the body, as well as the generalization of various subsystems (power, transmission, suspension, etc.) on it, and later today, it has successively added electronic and electrical architecture, intelligent computing platform, etc. But at the end of the day, the core is still a (partially) in-white body with rapid stretching adaptability.
From fuel vehicles to pure electric vehicles, what is the essence of frame changes? From "how to protect the occupants with a lump of iron stuffed in the front of the car" to "there is a big treasure under the car that cannot be touched", after all, if the battery has a three long and two short, the occupants are also in danger.
The change of power has changed the main composition of the vehicle, and the change of the structure of the whole vehicle has brought about different structural needs. In the fuel era, in order to adapt to stringent crash safety standards, fuel platforms require and can deploy multi-channel horizontal and longitudinal beam structures on the body floor (the universal design of platform models). In the case of previous heading collisions, the energy is transmitted through the front longitudinal beam of the cabin to near the firewall, and then mainly through the underbody longitudinal beam to the rear.
Bottom: The energy-absorbing path of the Subaru fuel platform
In the era of pure electricity, the bottom of the car is stuffed with battery packs, so this path obviously does not work. You will not be assured of the transmission of energy by the battery pack, and it is not realistic for a main beam to separate the battery pack into several pieces. Without changing these main structures, the battery pack can only be "externally attached" to the bottom of the car, or reduce the ground clearance, or greatly raise the base plate, not to mention the redundant structure to increase weight, which is a cliché.
Some general-purpose platforms will also make some changes to these main structures, but all of them come at a cost. Toyota's past so-called "e-TNGA platform" (not a strict definition), the front end of the battery pack has a significant two-sided miter cut, which reduces the usable volume of the battery pack, which naturally reduces the mileage (the upper limit).
The reason for this is that the new base plate stringer structure must bypass the battery pack, but it must be connected to the front cabin stringer with a smaller width in front, so the front end of the battery pack has to shrink, giving up the space for the two parts of the longitudinal beam to connect diagonally. The front cabin stringer, which is relatively small in width, is reasonable for fuel vehicles, but electric vehicles need more specialized structural arrangements.
For electric vehicles, the more ideal forward energy transfer path is from the front cabin longitudinal beam - the bottom plate longitudinal beam to the front cabin longitudinal beam - side sill longitudinal beam. On the one hand, this requires the front cabin longitudinal beam to be widened to the sides as much as possible, reducing the lateral "drop" between them and the side sill beam (but this is not infinitely increasing), on the other hand, the connection between the two, that is, the firewall to the front door post area, to do more structural optimization conducive to energy conduction.
Because the central part of the energy conduction path is vacant, the absorption and conduction of the energy of the forward collision is now more dependent on the side sill beam. You will find that the vast majority of electric vehicles with pure electric platforms have very thick door thresholds. The following evolution map of Volkswagen MQB (fuel) to e-Golf (MQB oil to electricity) and then MEB (pure electricity) is easy to illustrate:
See watermark for the source
Finally back to Toyota, the bZ platform belongs to the original pure electric platform, not because Toyota itself said that it is a pure electric platform, but because we can see that it abandons the fuel structure and "considers" pure electricity. In the bZ4X's body structure diagram, the necessary central bulge/exhaust channel for fuel vehicles has disappeared without a trace; the bottom longitudinal beam no longer exists, and the forward energy transmission is more dependent on the side sill longitudinal beam.
However, unlike the relatively radical Volkswagen, toyota's bZ platform has a more stable and conservative color.
MeB relies most of the energy transmission on the sill beam, and the Toyota bZ platform slightly reduces the pressure on the sill beam. The front cabin stringer is directly connected to the two "ramps" (black in the picture below), which distributes part of the energy to the body floor, and the bulge in the center of the bottom plate should also play a part, and the remaining energy will be directed to the side sill beam and then conducted to the rear body.
This may be because the front cabin stringers of the bZ platform do not extend to the sides as previously described, but maintain a more conventional width. The lateral "drop" between the front longitudinal beam and the sill beam is relatively large, and almost all the forward energy is directed to the sill beam like MEB, and the effect may not be ideal, or it will bring more structural weight gain.
As for the reason for this, it may be that considering that the wider front liner means that the front wheel swing area is smaller, that is, the cost of reducing the steering angle of the front wheel. For high-end models, this can be compensated for with rear wheel steering (RWS), but the Toyota bZ platform is not a luxury car platform, and it needs to think more about RWS-free models at the moment.
bZ4X
Toyota's approach is not unique, and the modern E-GMP platform also has a similar structure. The Korean way is to set up a small longitudinal beam in the center of the front of the body baseplate, and the energy from the front longitudinal beam will pass through the center of the bottom of the car, leading to the beam in the middle of the rear bottom, which also helps the side sill to share the pressure to a certain extent.
Modern E-GMP, note the red structure at the front of the baseplate
It's too early to talk about whether these two ideas are good or bad (how many cars haven't been sold yet). The difference in the energy transmission path of the forward collision is only one of the characteristics that distinguish the native pure electric platform from the general platform. To illustrate the problem, it is only because this is more obvious.
The core difference is actually very simple: from fuel vehicles to electric vehicles, the "heart" has changed from a large lump of iron at the front of the car to a "untouchable" area with a larger and better bottom. Cars driven by lithium battery energy (in order to get the best performance) need the most suitable structure for "carrying" lithium batteries, and the right set of structures on fuel vehicles has become more and more a constraint and obstacle for electric vehicles.
So they found that they and the old skeleton of the fuel platform were no longer together.