Audi's pure circuit, how to go with the remaining half? | technology flow

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In February, the SAIC Audi Q5 e-tron was officially launched, and it became the first MEB platform electric vehicle of SAIC Audi in China. Next, the more "original" FAW-Volkswagen Audi Q4 e-tron is also the matter of these months. The two belong to the north and south of the public, one two rows of five, one three rows of seven seats, just staggered from each other.

The ID. series with the Volkswagen logo took more than a year to step into the mainstream world of the pure electric market, and the Audi pure electric new car based on the MEB platform is of course not easy to persuade consumers to pay more budgets. But this window will not be too long, and the Audi brand's "Benge" platform will arrive.

A6 Avant e-tron concept car

If it weren't for the postponement caused by the epidemic, the A6 Avant e-tron concept car released in March would have been one of the highlights of Audi's Beijing Auto Show this year. It and the A6 e-tron concept car a year ago, are based on the Audi brand "exclusive" PPE high-end pure electric platform, and the previous Audi's first MEB model Q4 e-tron, also shortly after the release of the Sportback "variant" concept car.

As expected, FAW-Volkswagen Audi's PPE production line in Changchun will be ready next year, and the first production models A6 e-tron and Q6 e-tron (and SAIC Audi Q6 are two different things) should be unveiled this year.

Q6 e-tron spy photo

In Audi's current pure electric transformation plan, it includes four major model platforms. The e-tron SUV we are most familiar with comes from the all-electric variant of the MLB Evo, and the e-tron GT, which has been "coming soon", shares the J1 platform with the Porsche Taycan, which in turn is homologous to Panamera's MSB platform. Both are closely related to the fuel platform or the general-purpose platform, and neither will continue to be used in more models.

The real sense of pure electric power from the beginning is the MEB platform shared with the Volkswagen ID. series - you are already familiar with it; and the PPE pure electric platform, which is positioned in the middle and high-end, is not expected to hang the Volkswagen standard, and the PPE pure electric platform jointly developed with Porsche, the first to arrive is the A6 e-tron and Q6 e-tron production versions.

You can think of it as an advanced version of MEB, or you can think of it as a "more purely electric" (and at the same time slightly more practical) J1.

Compared with MEB, the PPE platform is first of all more suitable for mid-to-high-end models in terms of body form.

The MEB platform basically only needs to provide space-oriented models such as cars and SUVs, but the pursuit of sporty performance in high-end models makes the PPE platform must be able to adapt to a certain degree of coupe body. PpE's ground clearance height is set in the range of 152-217mm, and taking into account the support for air suspension, it can be adapted to the product range from coupes to high-end SUVs.

On the J1 platform, in order to keep the chassis battery pack from affecting the rear seat space, and thus not destroying the line under the rear roof, Porsche and Audi have adopted a "foot pit" design. But the "foot pit" comes at the cost of usable battery space, and the Taycan and e-tron GT have only gained up to 93kWh at a 2.9-meter wheelbase. At the same time, the foot position of the driver's seat is also significantly raised compared to similar fuel vehicles, and the sitting posture has been greatly limited.

The PPE platform has a regular battery pack shape similar to MEB, as well as the same larger module (12) layout, which can support the battery capacity to rise to 100kWh. In the trailer video of the PPE platform, two configurations appeared, low-floor and high-floor (high and low ground clearance), of which the battery pack height (thickness) also changed, that is, it may provide different battery thickness settings for cars and SUVs.

Also similar to meb, but different from the J1 platform is the location of the high-voltage module of the PPE platform. For pure electric vehicles, the charging interface is set on the rear body will be more conducive to reversing into the charging position.

But for fuel platform models, it is obvious that the front cabin that is emptied is an ideal space for a generous space, so the charging interface is usually arranged on the front fenders. If you insist on the rear body, especially the fast charge interface, the high-voltage line needs to pass through the entire body from the rear to the front, which will increase the weight and cost.

The Taycan's DC and AC charging modules are arranged in the front cabin, with charging ports located on either side of the front fenders

The Model 3's DC-DC module is integrated into the end of the battery pack

Models designed for pure electricity in the first place tend to integrate high-voltage charging modules into the rear of the battery pack rather than cram into the front space of the car , which does not have the huge space that would have been left for the internal combustion engine. The MEB's high-voltage charging module is integrated into the rear motor, while the PPE is placed under the back seat of the battery module like the Tesla Model 3.

Therefore, meb (in addition to the front-drive configuration) and THE PPE platform put the fast/slow charging interface on the rear body, and because of the rear-drive drive layout, the main high-voltage cable in the car does not need to pass through the vehicle length. It can be said that the rear drive-oriented, post-high-voltage module, and post-fast charging interface are the most ideal pure electric platform layout at present.

The high-voltage charging cable of the PPE platform leads to the end of the battery pack

As a mid-to-high-end platform, PPE adopts an 800V high-voltage architecture like the J1 platform and supports up to 270kW super fast charging, resulting in a charging rate consistent with the Taycan. The more economical MEB platform is 400V, and the charging power is capped at 125kW.

In Europe, Audi has the support of the Ionity charging system, but when it comes to China, Audi needs another way. Taycan can only enjoy the charging speed benefits of 800V at a few Porsche supercharger stations. The next PPE platform is not destined to be niche like several models on the J1 platform, and it needs the high-density support of the ultra-high voltage charging system.

In terms of chassis suspension, the existing "standard" of the PPE platform is the front and rear five-link structure with adaptive air suspension, which has gradually become a common choice for high-end electric vehicles (see "What is the suspension without suspension in the electric age?"). 》）。 Unlike the former McPherson structure, which is highly economical on the MEB platform, the PPE's front five-link suspension is easier to adapt to the front axle high-power motor, thereby increasing the upper limit of vehicle power available on four-wheel drive models.

In fact, in addition to the Audi A6 e-tron and Q6 e-tron (which may come with L) that are destined for next year, there is also a PPE platform model that has also been determined, that is, Porsche's next-generation pure electric Macan. The next-generation Macan will share a considerable part of the body parts with the Q6 e-tron, and the anecdote story of the "Porsche discovery of the Volkswagen logo" in the fuel era may still happen.

Audi is not the only two-legged walk in the BBA, in addition to bmw, which is not the usual way in terms of electric vehicles, Mercedes-Benz has also planned two pure electric platforms of EVA (EVA2.0) and MMA, of which the former has been mass-produced for EQS, EQE, etc., and the latter will be used to create low-end models and have a hybrid configuration of "electric oil". The Audi entry platform has been mass-produced, while Mercedes-Benz is a high-end platform ahead.

Because of the sharing of MEB platforms with Volkswagen and Skoda, Audi's existing Q5 e-tron and Q4 e-tron need to face certain market pressures, especially in the case that the Volkswagen ID. series itself has not yet fully opened the situation. The MEB platform itself is also differentiating, with the front-drive cheap configuration (MEB21) and the rear four-link configuration (MEB41, ID.Buzz) appearing, but it is not enough to make the Audi MEB model stand out.

The success of Taycan has proven that high positioning is not a problem, the problem is to provide a suitable product in a high demand market. The Mercedes-Benz EVA platform is ready, but it will take time to expand downward from EQS, and the new car brands are attacking a wide range of around 400,000 yuan, if Audi's PPE models can directly enter this market in 2023, it may become the most effective step in Audi's pure electric strategy.