Deep roots produce new branches: How does the all-new Hi4 from Great Wall Motors achieve "electric four-wheel drive for all"?

Author: Mu Mu

If there is one word to accurately describe this year’s automotive market, “price-stomping” is undoubtedly the most appropriate one.

Starting with the Citroen C6 priced at 120,000 yuan, the automotive market opened the “Pandora’s Box”. After the policy was introduced in Hubei, automobile production centers in Geelyn, Anhui, Guangdong, Chongqing, and others have also launched similar price reduction and subsidy policies.

Therefore, at the “Intelligent New Energy Conference” held by Great Wall Motor in the past, Wei Jianjun, Chairman of Great Wall Motor, raised a soul-searching question:

“Are you anxious about the current round of price reductions?”

In this environment, there are only two possibilities for not being anxious: either the sword of Damocles has not fallen on one’s head and they are still bouncing in the comfort zone, or they are already gasping for breath and have no strength to fight back.

In a sense, it is anxiety that gives companies a sense of crisis and fresh blood for survival and provides an opportunity to think about solutions.

For new energy vehicle companies, apart from traditional fuel vehicle companies dealing with the switch of emission policies and committing to suicide-type price reductions, the theme of 2023 and even the next few years will be “reducing costs and increasing efficiency.”

The core of “reducing costs and increasing efficiency” has two points: firstly, starting from the technology itself, reducing complexity while ensuring the user experience. Secondly, starting from the supply chain, improving the vertical integration ability and making the cost of parts immune to external environmental fluctuations.

It sounds simple, but few can actually achieve it. But once you have mastered this “killer move,” the automaker is equivalent to obtaining the “Dragon Slaying Saber ” in the martial arts world.

“Good Quality and Low Price” Is Still the Killer Move

In January of this year, BYD announced that it sold 1.8685 million vehicles in 2022, of which new energy vehicle sales reached 1.8635 million units, making BYD the world’s largest new energy vehicle company.

From the perspective of specific models, the Dolphin, the Yuan series, and the Song series firmly occupy the 100,000-200,000 yuan price range, while the Dolphin, Tang, and Han are popular in the 200,000-300,000 yuan range.

The upcoming “Sea Gull” will also support BYD’s goal of selling 4 million vehicles annually in 2023.

From the perspective of technology, DM-i technology achieves a balance in cost, energy consumption, and user experience, while from the supply chain perspective, BYD has strong vertical integration capabilities from battery raw materials to new energy vehicle three-electric systems to the downstream complete vehicles field.And this allowed it to withstand the impact of the epidemic in the first half of last year with a vertical supply chain system and decentralized production bases.

Similarly, Tesla also has a similar idea.

In 2022, Tesla delivered more than 1.3 million new cars, with a gross profit margin of nearly 30% despite the downward price trend.

The core reason is also that Tesla has reduced costs through technology such as integrated casting and continues to expand production scale through continuous production acceleration on the manufacturing end, and continuously improves the localization rate of parts for domestically produced Tesla models on the supply end.

So we can confirm these two conclusions: To become a leading new energy vehicle company in the market, simplifying technology and ensuring experience, as well as vertically integrating upstream and downstream supply chains to ensure independence, are the two core elements.

Both of these points require car companies to have strong research and development capabilities and coordination capabilities, and Great Wall Motors has such a foundation. From the perspective of the new Hi4 technology launched by Great Wall Motors this time, the purpose is simple and direct:

“Use technology and system as a driving force to grab all our market share back.”

The new Hi4 smart four-wheel drive hybrid technology promotes technological equality

“Through the new Hi4, achieve the purchase of a 4WD with the price of a 2WD and promote the era of electric four-wheel drive for everyone.”

Obviously, Great Wall Motors has figured out the core points of market competition this time: cost and price.

But there is another premise: user experience cannot be compromised.

Therefore, let’s look at how this system balances the two from a technical perspective.

The new Hi4, where H (Hybrid) represents hybrid, i (intelligent) represents intelligence, and 4 represents (4WD) four-wheel drive system. This is a self-developed intelligent control four-wheel drive hybrid technology by Great Wall Motors, which adopts the architecture of dual motors in series and parallel on the front and rear axles.

Great Wall Motors has developed a new generation of powertrain components for this architecture, including: hybrid-specific engines, hybrid-specific transmissions, high-power and efficient electric rear axles, and low-impedance power batteries.

The all-new Hi4 comes with two sets of powertrains, covering power from 220 kW to 350 kW:

  • 1.5L + 2-speed transmission + 70 kW motor + 150 kW motor + 19.94 kWh battery;
  • 1.5T + 2-speed transmission + 80 kW motor + 150 kW motor + 27.5 kWh battery.

The all-new Hi4 is not a simple modification of Great Wall Motors’ Lemon Hybrid DHT technology, nor is it a mechanical four-wheel drive solution for the Tank series. Instead, it is a solution specially designed for the front transverse platform.

The most ingenious part of the system is that it uses two motors to achieve an electric four-wheel drive mode, which has significant cost advantages compared to the familiar P1+P3+P4 architecture with three motors.

In terms of the engine, the all-new Hi4’s 1.5L/1.5T hybrid engine has undergone many optimizations to reduce energy consumption through electrification: a 350-bar direct injection system, the removal of the crankshaft belt system, and the use of electrically driven water pumps and compressors, in combination with the Miller cycle and the Atkinson cycle for a high compression ratio of 16:1.

The thermal efficiency of this hybrid-specific engine reaches 41.5%, making an indispensable contribution to improved fuel economy.

Based on the intelligent energy management and intelligent torque vector control systems, the all-new Hi4 can realize intelligent switching between nine modes: pure electric two-wheel drive, pure electric four-wheel drive, series mode, first gear direct drive, second gear direct drive, parallel two-wheel drive, parallel four-wheel drive, single-axis energy recovery, and dual-axis energy recovery by calling on the front and rear dual motors, hybrid-specific engines.

The P1 motor located on the front axle is the essence of the all-new Hi4. This front axle motor uses technology such as variable lubrication oil flow control, low resistance and high efficiency bearings, and low viscosity oil to achieve an overall efficiency of 98%.

By coupling and decoupling the clutch, this motor can be used as a generator to supply power to the battery for extended range mode, as a driving motor in pure electric mode to form a four-wheel drive in conjunction with the rear motor, or in parallel direct drive with the generator.

By using two-stage DHT, the generator can participate in direct drive at a speed of about 40 km/h, ensuring that the engine always operates in the optimum efficiency range from low to high speed.

In the rear axle, the newly equipped Hi4 uses flat wire card-winding to increase the slot filling rate, and the NVH control of the electric drive system is guaranteed by low harmonic design.

Because the front and rear axles are completely decoupled, this system can achieve various combinations and select the most energy-efficient/performance-optimal driving scheme after system judgment. This is not possible with the front-drive DHT platform.

From the perspective of application scenarios:

  • Under urban driving conditions, the Hi4 can select pure electric two-wheel drive, extended-range (series) mode, engine direct drive, and other modes. Pure electric 4WD and parallel 2WD/4WD can be selected under high power demands.
  • In high-speed cruising, the 2nd-gear direct drive mode can be selected for the engine to operate in the high-efficiency range. In deceleration and braking, single-axis or dual-axis recovery modes can be selected to minimize energy loss.

In summary, this system can achieve better energy efficiency performance than the extended-range and single-stage direct-drive systems. According to data from Great Wall Motors, vehicles equipped with single-stage direct-drive/extended-range can use pure electric mode for 30% of the mileage and series mode for 70% of the mileage under WLTP urban driving conditions.

Great Wall Motors’ new Hi4 can achieve 30% of the mileage using pure electric mode, 37.8% using series mode, and 32.2% using 1st-gear direct drive, increasing efficiency by 2.24% and reducing fuel consumption by 5.06%. This also explains why two-stage direct drive can achieve better energy efficiency than single-stage direct drive and extended-range.

Additionally, Great Wall Motors’ new Hi4 system also incorporates double-axis kinetic energy recovery, which provides stable and balanced braking force on low-adhesion road surfaces to avoid locking. The battery pack that comes with it can also support a maximum charging power of 150 kW, which is rare for hybrid models with small batteries and further improves the overall energy consumption of this system.From the models under the Great Wall Motors brand to Wei brand and Tank brand, SUVs have always been the core label of Great Wall Motors.

For consumers, four-wheel drive can meet more travel scenarios; for Great Wall Motors, this four-wheel drive system can also achieve economies of scale by being applied to multiple brands and series of models under its umbrella.

Therefore, the four-wheel drive capability has naturally become an important consideration. Through the iTVC intelligent torque vector control system, this four-wheel drive system can dynamically distribute torque in situations such as low-adhesion road surfaces, high-speed turns, and off-road terrain, providing better off-road performance than single-motor front-wheel drive.

Great Wall Motors stated that the new Hi4 technology will be officially launched in April this year, and 4WD technology will be popularized in all its products by 2024.

Li Ruifeng also stated in an interview:

“2023 will be an important year for the intelligent new energy transformation of Great Wall Motors. Haval brand is a brand that carries an important mission as a brand with large sales and cutting-edge category. The Haval new energy transformation is also a very important strategic project for us this year.”

Therefore, it can be expected that Great Wall Motors will enter the 100,000 to 200,000 market with the Haval brand completed the transformation in 2023 and compete head-on with BYD.

However, the core of the competition still lies in the price. The reason why BYD’s new energy models can gain popularity is that it has lowered the prices of traditional fuel vehicles and new energy models to the same level. People find that new energy models have advantages in terms of the cost of using and driving experiences.

Therefore, the pricing of the subsequent models equipped with the new Hi4 technology will be critical.

Every ecosystem is at the billion-level

In 2022, Great Wall Motors’ total sales volume was 1.067 million vehicles, with a total revenue of CNY 137.351 billion and a net profit of CNY 8.279 billion. The total revenue and net profit have maintained a considerable growth rate, and the net profit increased by 23.09% year-on-year.# Great Wall Motors with its deep roots has an insurmountable foundation that is difficult for others to surpass. Facing the next competition, Great Wall Motors has ample funds and rich technological achievements.

In addition to the brand-new Hi4 introduced this time, Great Wall Motors’ systematic layout in the core supply chain has always been a hidden line of development. Based on “Forest Ecosystem,” Great Wall Motors has deep accumulation in intelligence, new energy and power, and vehicle manufacturing.

Regarding power batteries, Hunan Corun New Energy has laid out power battery packs of various chemical systems such as lithium iron phosphate, lithium manganese iron phosphate, cobalt-free battery, ternary lithium-ion battery, and ternary sodium-ion battery. The power battery pack of Hunan Corun New Energy will also be adopted in the newly launched Ideal L7 Air model, providing fertile development soil for Hunan Corun as the market urgently need power batteries.

In terms of electric drive technology, Hunan Corun EasyDrive has developed a series of products such as motors, electric drives, and gearboxes for pure electric and hybrid vehicles. Hunan Corun EasyDrive has built two major platforms: M and L, with a series of products ranging from 100 kW to 220 kW, covering passenger cars from Grade A to Grade D.

For SiC semiconductor components, Great Wall Motors uses the CSS technology platform, which increases the module control density by 50% and reduces cost by 30%. Great Wall Motors plans to produce 1.2 million sets of vehicle-level modules annually.

In terms of intelligent driving, HoloMatic has already laid out full-stack resources from bottom-level software middleware toolchains to upper-level application software. HoloMatic has launched a city NOH navigation-assisted driving product that can be mass-produced and landed. At last year’s HoloMatic AI Day, we also saw many of its technological ideas leading the industry.

In the field of intelligent driving hardware, GreatWall Motors has developed the Rebo Perception, which includes self-developed perception hardware such as a car-mounted camera with a 17 million pixel photosensitive chip and a 4D millimeter-wave radar. Meanwhile, Neousys Technology has self-developed a high-performance computing platform that works with these perception components to achieve an intelligent driving architecture.

Regarding cabin intelligence, Neousys Technology has self-developed the V3.5 high-performance cabin platform, and the sales volume of vehicles equipped with it has surpassed 200,000 units. The more powerful V4.0 cabin platform is also about to be launched. Furthermore, in the recently released second-generation Haval Big Dog, we can see a cabin equipped with the second-generation Coffee OS. The voice experience can achieve a wake-up speed of 250 milliseconds and car control execution speed of 900 milliseconds.

In such an ecological system, GreatWall Motors has a strong say in the R&D, production, and entire vehicle chains. In contrast to the approach of new energy vehicle startups burning money to lay out the upstream industry chain, GreatWall Motors possesses a mature and complete core barrier, which has become their confidence and trump card in reversing their fortunes and confronting the era of new energy in 2023.

Final Thoughts

Technologically, the brand new Hi4 released by GreatWall Motors at this Intelligent New Energy Conference shows that they have found a balance between cost control and user experience.

Pricing-wise, GreatWall Motors has declared “buy 2WD at the price of 4WD, and promote the era of electric 4WD for all” through the new Hi4, directly launching a strong attack against DM-i.

In terms of the system, GreatWall Motors has mature vertical integration capabilities and controls its own industry clusters in the upstream and downstream of new energy vehicles, each of which has the potential to thrive on their own.

The rich product lineup of GreatWall Motors is built upon a solid foundation, and they have many outstanding aces up their sleeve.

Therefore, 2023 is a crucial year for GreatWall Motors. They aim to use new technology, new systems, and new products to meet the rapidly growing demand for new energy vehicles and regain their own market share.

This article is a translation by ChatGPT of a Chinese report from 42HOW. If you have any questions about it, please email bd@42how.com.