Technical Post: Application of Diversified Energy Systems in eVTOL [Electric Drive System Conference]

On June 21, at the 2025 SMM (4th) Electric Drive System Conference & Drive Motor Industry Forum - eVTOL Electric Drive System Forum, jointly hosted by SMM Information & Technology Co., Ltd., Hunan Hongwang New Material Technology Co., Ltd., Louxing District People's Government, and the National-level Loudi Economic and Technological Development Zone, Wang Yunzhong, Chief Engineer of the R&D Headquarters of Dongfeng Motor Group Co., Ltd., shared insights on "The Application of Diversified Energy Systems in eVTOL."

01 Opportunities and Challenges in the Development of the Low-Altitude Economy

Opportunities and Challenges in the Development of the Low-Altitude Economy - Definition of the Low-Altitude Economy

The low-altitude economy is a comprehensive industrial form driven by multi-scenario low-altitude flight activities, encompassing new quality productive forces composed of technologies such as low-altitude aircraft and low-altitude intelligent connected networks. It radiates and promotes the integrated development of industries including low-altitude manufacturing, low-altitude flight, low-altitude support, and comprehensive services.

The airspace height range involved in the low-altitude economy is below 1,000 meters, and can be extended to airspace within 3,000 meters based on the characteristics of different regions and actual needs. The flight altitude of manned vertical takeoff and landing aircraft is generally below 300 meters.

Opportunities and Challenges in the Development of the Low-Altitude Economy - Three Major Types of Aircraft in the Low-Altitude Economy

The manufacturing of low-altitude aircraft is the most important physical industry among the four major sectors of the low-altitude economy. Low-altitude aircraft mainly include traditional helicopters, various drones, and flying cars.

In a broad sense, flying cars refer to vehicles designed for low-altitude intelligent transportation and three-dimensional smart transportation, mainly including two major types: land-air amphibious vehicles and electric vertical takeoff and landing aircraft (eVTOL) (excerpted from the "White Paper on the Development of Flying Cars").

Flying Car

Originally, it referred to an airborne vehicle with land-air amphibious capabilities. Currently, eVTOL, as a popular means of transportation for low-altitude travel, is also defined as an important development form of flying cars.

eVTOL Electric Vertical Takeoff and Landing Aircraft

An electric aircraft utilizing electric vertical takeoff and landing technology, capable of hovering and taking off and landing without the need for a runway.

It is environmentally friendly, low-noise, highly safe, and has a total life cycle cost that is one-fifth that of a helicopter.

In the future, its popularization will approach the scale of automobiles, and its large-scale production and supply chain can fully leverage the automotive manufacturing industry.

Drones, helicopters, and eVTOLs (Electric Vertical Take-off and Landing, eVTOL) are the three major physical carriers for realizing the low-altitude economy.

Compared to drones, eVTOLs have a broader range of functions beyond carrying passengers and cargo. Compared to helicopters, eVTOLs offer advantages such as low carbon emissions, low noise, low cost, no need for runways, and good stability, gradually becoming the mainstream solution for urban air mobility.

Opportunities and Challenges in the Development of the Low-Altitude Economy - Low-Altitude Application Scenarios

It lists scenarios such as production and operation, public services, and aviation consumption.

Commercialization Path: Prioritize rigid demands in non-urbanized scenarios, conduct pilot projects in urban scenarios first, and achieve full-scale integration in the later stage.

Opportunities and Challenges in the Development of the Low-Altitude Economy - Development Opportunities

The low-altitude economy has received significant attention from national policies, with frequent policy releases and the gradual opening of low-altitude airspace to promote its development.

It aligns with the future trends of three-dimensional, electrified, and intelligent transportation, representing a blue ocean market that urgently needs to be developed.

High Altitude: Aircraft ⇒ Flight (Considering safety factors and aviation control requirements, it is difficult to significantly increase the flight speed of civil aviation);

Low Altitude: None ⇒ Flying Car (Point-to-point solution for the last mile, addressing urban congestion and improving traffic efficiency);

Ground: Cars, Public Transportation, Rail Transportation ⇒ Unchanged (However, the scope of personalization expands, the level of intelligence deepens, the Internet of Things becomes more prevalent, and cities become smarter);

Underground: Subway ⇒ Subway (It is predicted that there will be relatively small changes within the next 30 years);

The transportation mode in the next 10-20 years will be a "highly intelligent three-dimensional transportation network dominated by new energy."

The progress in electrification and intelligent technologies of NEVs promotes the electrification and intelligent development of low-altitude flight vehicles;

The scalability of automobiles, mature industry chain, and application of electrification technologies can significantly reduce the cost of flight vehicles, making popularization and widespread adoption possible in the future.

Opportunities and Challenges in the Development of the Low-Altitude Economy - Facing Challenges

►As a cross-border integrated product, the management functions of eVTOL are not yet clear, and there are common difficulties such as the lack of unified regulations, standards, and airworthiness certification.

Currently, all are based on the "case-by-case" approach under civil aviation airworthiness conditions, with special conditions formulated separately for each project, leading to a long cycle. There is an urgent need for relatively unified certification standards.

►Technology still needs breakthroughs, there is a lack of market traction and supporting facilities, and business models still need to be explored.

Prominent technological bottlenecks: Insufficient driving range, weak communication security, and technologies for safe obstacle avoidance and noise reduction.

Shortage of infrastructure: Improvement of airspace management, construction of takeoff and landing sites, and energy supporting networks.

Lack of market traction: Insufficient consumer awareness, high market prices, and limited application scenarios.

Insufficient industrial integration: Imperfect communication, navigation, and surveillance systems, inadequate operational supervision and management, and inconsistent cross-industry standards.

In the early stages of development, more policy guidance and support from the national and local governments are required to promote industrial growth and improve supporting infrastructure.

02 eVTOL Technical Pathways and Key Technologies

eVTOL Main Technical Pathways and Key Technologies - Technical Pathways

Technical pathways and configurations will be selected based on different application scenarios and technological development stages, with multiple pathways and configurations coexisting.

From a technological development trend perspective, tiltrotors are gradually becoming mainstream, and as the industry and technology further advance, they will evolve toward land-air integration.

eVTOL Main Technical Pathways and Key Technologies - Technical Architecture

The smart cockpit, autonomous driving, power and ESS share common technologies with NEVs, enabling complementary advantages in the industry chain, integrated innovation, and collaborative development.

The automotive industry's supply chain and economies of scale help reduce eVTOL costs, while well-established sales channels facilitate widespread adoption.

Automakers are emerging as the primary players in the flying car sector, not only enhancing brand value through cross-industry ventures but also investing in flying car development and low-altitude operations.

The cut-throat competition in the NEV industry drives early adoption of future transportation forms, seeking opportunities for "overtaking in a new lane," with flying cars being a key future direction.

eVTOL Main Technical Pathways and Key Technologies - Electric Drive System

eVTOL propulsion motors emphasize high torque and require sustained high-power output, with stricter cooling and safety redundancy requirements, whereas automotive motors focus on high speed and power density.

As a core system, eVTOL propulsion motors demand extremely stringent safety and reliability standards, requiring airworthiness certification, which presents high entry barriers.

As the eVTOL industry evolves, independent airworthiness certification for key components like motors and controllers will become an inevitable trend.

eVTOL Main Technical Pathways and Key Technologies - Power Battery

eVTOL power batteries far exceed automotive power batteries in discharge capability, energy density, and safety requirements.

It also outlines development targets for aviation-grade power batteries, 2023-2035.

03 Application of Diversified Energy Systems in eVTOL

Performance requirements vary significantly across different usage scenarios, particularly in driving range, necessitating diverse energy systems.

Current power battery performance struggles to meet demands exceeding 200km range, making hybrid power a viable solution for long-range eVTOLs.

Hybrid systems currently include oil-electric and hydrogen-electric hybrids, with oil-electric technology being relatively mature. Fuel cells can achieve zero emissions and ultra-long range but rely heavily on policy guidance and support due to technological and infrastructure limitations.

Large, heavy-duty eVTOLs equipped with hybrid power systems can achieve several times the maximum range and payload compared to pure electric models.

If large, heavy-duty eVTOLs are equipped with pure electric power, the battery accounts for over 40% of the total aircraft weight, resulting in an excessively low proportion of available payload.

Hydrogen fuel cell aircraft are less commonly used. Currently, encouraged by policies, a number of hydrogen-powered aircraft products have emerged domestically and overseas. The advantage of hydrogen fuel cells lies in their high energy density, but they are limited by the power density of the stack and system, making them only suitable for products with small payloads and long ranges.

Dongfeng's hybrid power system: Based on China's Top 10 Engine "Mach Power" engine, it has developed 1.6T and 2.0T aviation engines. The range extender's supporting generator iG2-150: a 2-in-1 assembly with high integration, high efficiency, and high compatibility with the engine.

It also elaborated on Dongfeng's fuel cell system and Dongfeng's solid-state battery, among others.

》Click to view the special report on the 2025 SMM (4th) Electric Drive System Conference & Drive Motor Industry Forum