Highlights of the Xiaomi Automobile SU7 Launch Event

On December 28, 2023, Xiaomi Automobile held a launch event where we witnessed the mass-produced version of the SU7. Additionally, it was revealed that Xiaomi plans to start selling it in the first half of 2024.

From the decision to build cars to the launch event, it took 1003 days. In these years of drastic changes, the development and production efficiency have been truly impressive.

What was revealed at the event was merely the paper performance of the SU7. We will have to wait a few months for the actual car to arrive and undergo various evaluations before we can truly understand its capabilities. Let's talk about what we should focus on in the real car tests in a month or two, and then make a prediction about the development of Xiaomi Automobile.

Coefficient of Drag

The SU7 has a wheelbase of exactly 3 meters, with the length just 3 millimeters shy of 5 meters and the width 4 centimeters short of 2 meters. It is a mid-to-large-sized sports sedan. The car's shell features a streamlined design that emphasizes aerodynamics. Many say that its appearance is very similar to the Porsche all-electric sports sedan Taycan, and I agree.

The SU7 has an obvious difference in exterior design from the electric vehicles of Wei, Xiao, and Li in recent years, which is a more complex air duct design.

Early pure electric vehicles were developed using the platform of fuel cars, so the air intake grille for cooling the front engine and its associated air ducts remained largely unchanged.

Later, as pure electric vehicles started to be independently developed from scratch, there was no need to retain traces of fuel vehicles in the chassis and shell design. Therefore, many pure electric vehicles, especially SUVs and MPVs that do not pursue extremely low drag coefficients, do not have complex air intake designs on the front.

However, the SU7 has numerous air ducts on the front, sides, and rear, all for achieving ultra-low drag. The event highlighted a drag coefficient of 0.195, claiming it to be the lowest in the world for mass-produced cars. The previous record-holder was the Aiways Hyper GT, at 0.197.

Generally, most sedans achieving under 0.25 are considered good, so 0.195 is quite an astonishing figure.

Of course, there are some controversies over this figure. For example, it was measured using a version of the car without a top-mounted LIDAR, which would naturally be lower. But even so, this value is still remarkable.

Both versions of the SU7 have recessed door handles, not hidden ones. Many cars use hidden handles to achieve ultimate aerodynamic performance.

But in the recent heavy snow in the north, we saw many hidden handles frozen and unable to pop out. Achieving such an extreme drag coefficient without using hidden handles, even for the non-LIDAR version, indicates extensive effort in aerodynamics.

Since the drag coefficient significantly affects the range of pure electric vehicles at high speeds, in real car tests, we can pay attention to the SU7's range at sustained high speeds. Remember, we are interested in the range under continuous high-speed conditions.

Range

Today's pure electric cars have their range labeled according to the CLTC standard. Four or five years ago, the NEDC standard was commonly used. In the period when both standards existed, almost all manufacturers only labeled CLTC because it results in higher range figures. Hence, cars labeled with a CLTC range of 600 kilometers typically only achieve about 400 kilometers in urban and highway mixed roads during spring and summer.

The harshest test for range is in winter. Driving at a constant top speed of 120km/h on the highway, with 3-4 people in the car, and using heating or seat heaters to ensure passengers are warm, the continuous range in kilometers is about 0.35-0.60 times the CLTC range. We call this the discount rate. Poorly performing models fall below 0.40, most are in the 0.45-0.55 range, and the best can barely reach 0.60, almost never exceeding this number.

In summer, the discount rate generally increases by about 20%, ranging between 0.42 and 0.72.

So, in real car tests a few months later, we can check whether the high-speed range exceeds the winter rate of 0.60 and the summer rate of 0.72.

This time, the SU7 comes in two versions – the standard version with a range of 668 kilometers and the Max version with 800 kilometers. If it can exceed the winter rate of 0.60, these two versions will be among the few models capable of exceeding 400 kilometers in harsh winter conditions at high speeds. Previously, there were only a handful of models that could exceed 400 kilometers.

Cell-to-Body (CTB) Battery

Another point worth mentioning is the battery structure.

The SU7 adopts a Cell-to-Body (CTB) integrated structure. Simply put, the battery cells are directly mounted on the chassis, and the top cover of the battery cells serves as the cabin floor, with seats directly installed on the top cover of the battery pack.

The advantages of this approach include cost reduction, weight saving of over a hundred kilograms, more batteries, higher energy density, and significant longitudinal space saving. For instance, the interior height and minimum ground clearance can both increase by several centimeters, which is quite valuable.

Moreover, the explosion-proof valves of the SU7's batteries face the ground, not upwards, so if gas is generated inside the battery, it poses less danger to people when released.

Of course, implementing CTB sounds easy, but it's actually a method that has been slowly explored over about ten years.

Tesla only started mass-producing such models from 2021.

The earliest designs comprised four parts at the bottom of the car – cells, cell modules, battery pack, and chassis. For example, early Teslas used 7104 18650 cells, 444 cells per module, 16 modules in total, forming a battery pack, then embedded in the chassis.

Later, as individual cells could be made larger, the alloy frame of the module was removed, and dozens of large cells were embedded directly into the battery pack and then into the chassis. This structure, consisting of cells, battery pack, and chassis, is called CTP, like BYD's blade battery.

Only in the last two years have pure electric cars evolved to embed cells directly into the chassis, eliminating both the module frame and the battery pack frame, i.e., CTB.

However, there are also disadvantages. For example, without various metal frames to assist in heat dissipation, the thermal density is higher. Also, if battery maintenance is needed, it can only be returned to the factory, as 4S stores can hardly handle it. This directly leads to higher insurance premiums for CTB models.

Another point is that, because of the integrated car body and battery design, it inevitably gives up on battery swap technology. We have previously discussed battery swapping and super-fast charging as two ways to replenish energy. The conclusion is that if there is a real need for rapid energy replenishment, such as charging for 10 minutes to travel three or four hundred kilometers, battery swapping is the more universally applicable method. Super-fast charging is impractical and only for display, not practical use. Battery swapping requires at least a CTP battery structure, so CTB essentially forgoes battery swap technology.

Front Trunk Volume of 105L

Additionally, the event mentioned that the car has the largest front trunk in the domestic market at 105L, significantly larger than Tesla's 89L.

At first glance, this seems extremely convenient and practical, but it actually reflects more on the design strength. This implies that components like the air conditioning system, electric motor cooling system, vehicle control unit, radar sensors, cameras, and lighting system must be highly integrated to free up such a large space of 105L in the front.

Conclusion:

All these are aspects not seen or highlighted at the Xiaomi event. From these points, we can roughly conclude:

Despite it being Xiaomi Automobile's first foray, the body structure and chassis design level of the SU7 can be considered top-notch in the fiercely competitive pure electric vehicle market. Xiaomi has been highly efficient in the car-building process over more than three years.

However, there are also several disadvantages:

Firstly, there are many domestic brands and models of pure electric vehicles today, and the market is nearly saturated. Especially under the current economic conditions, people's willingness to change cars or the frequency of changing cars in the coming years is far less than in the past five years. At this point, those who intended to switch to electric vehicles have done so, and the rest are likely to continue using their current vehicles, tightening their belts in terms of spending. When Xiaomi set the specifications for the SU7, this situation had not yet emerged, so although the SU7's indicators are excellent and the design outstanding, given the market environment in the next two years, its specifications seem a bit too high, potentially making it less accessible to a wider audience.

Xiaomi's biggest advantage is its price-performance ratio. For example, in the smartphone market, you can enjoy the best performance for as little as 1999 yuan, and a satisfactory experience for just 799 yuan. This advantage is due to Xiaomi's decade-long accumulation in the smartphone industry, allowing it to spread R&D costs over a large volume of products.

Other automakers also have some models with particularly good price-performance ratios, even priced just above cost, and have significant sales volumes. They can afford such pricing because they have a dozen other models that are profitable. By dedicating one model to capture market share and boost brand influence, thereby driving sales of other profitable models, these standout models can afford not to be profitable, hence the term price-performance ratio.

But Xiaomi currently has only this one model in the automotive sector, making it hard to spread costs across other models.

Despite Xiaomi's efforts to dilute costs, such as the production qualification of the SU7 being with Beijing Off-Road, and the production being divided into two phases of 150,000 units each, totaling 300,000 units, this volume for a brand-new flagship model is aggressive. Presumably, Xiaomi hopes to lower costs as much as possible to leverage its price-performance advantage, hence the large order volume. But with only one model, and possibly positioned too high, the car's price will definitely not be at the level of Xiaomi's 1999 yuan flagship phones.

The final point is that the event did not reveal the price. After the above analysis, you might understand why the price was not disclosed.

Lei Jun, staking his entire reputation on what he calls his last venture in life, may face the biggest challenge in pricing his first car model. Forget about 149,999 yuan; I think even 249,999 yuan might not be enough. Moreover, I predict that Xiaomi Automobile will encounter significant difficulties at the outset.