Abstract:In view of the diversity of battery performance requirements for eVTOL at different stages of development and application scenarios, BAK Battery has developed a forward-looking system technical plan from small cylindrical batteries to large cylindrical batteries from the three dimensions of model, structure and chemical system, which has the characteristics of high energy density, high power, high safety, fast charging and long cycle, and provides reliable power guarantee for the low-altitude economic market.
Land, Sea, Sky...... With the continuous evolution of lithium battery technology and the continuous expansion of application scenarios, the imagination of work, life, and transportation from the ground to the low altitude is reflected in reality, and the low-altitude economy is gaining momentum for the "low-altitude economy".
In terms of policies, since 2023, support policies have been intensively introduced from the national level to the local level for the eVTOL (electric vertical take-off and landing aircraft) industry, which is a key product of the low-altitude economy. In 2024, the low-altitude economy will be written into the government work report for the first time. Among them, the research and development of aviation power battery technology continues to advance, and the "Implementation Plan for the Innovative Application of General Aviation Equipment (2024-2030)" proposes to support battery, motor and other advantageous enterprises to increase R&D investment, improve product performance, and cultivate a number of well-known brand products. Promote the mass production of 400Wh/kg aviation lithium battery products, and realize the application verification of 500Wh/kg aviation lithium battery products.
In terms of market, the general aviation industry is the main body of the low-altitude economy, and it is an important measure to promote the development of the low-altitude economy to accelerate the innovative application of general aviation equipment with unmanned, electrified and intelligent technical characteristics. In addition to eVTOL startups, at present, Xpeng Huitian, GAC Group, Musk and other car companies have begun to lay out and successively release eVTOL-related products. In addition, lithium battery companies have also carried out technical research on aviation-grade batteries, and some companies have launched aviation-grade battery products.
The rise of the trillion-dollar market in the low-altitude economy
With a series of strong policy support and market promotion, the low-altitude economy is expected to develop rapidly.
It is reported that eVTOL can be divided into multi-rotor, composite wing, tiltrotor and other types, and the early application focuses on commercial operations and government services, such as airbus, emergency firefighting, and even express delivery business, and then gradually expands to the private travel market.
According to the forecast released by EVTank, the global eVTOL ownership will reach 26,000 by 2035, driving the cumulative global eVTOL market size to reach 160 billion US dollars. In the future, with the batch delivery of eVTOL, the market size of the entire eVTOL industry chain will reach trillions.
Dr. Xu Yan, Director of BAK Battery Innovation Process Department
"The low-altitude economy is one of the representatives of new quality productivity, which is expected to drive the trillion market space." Dr. Xu Yan, director of BAK Battery Innovation Technology Department, said in an exchange with the battery network, but according to the statement of the National Development and Reform Commission, the low-altitude economic field is still in its infancy. Despite the strong policy drive and the high attention of the market, the actual industrial development, infrastructure construction, and the improvement of the market mechanism are still in the initial construction.
Xu Yan said that the rise of the low-altitude economy provides huge growth space and development opportunities for battery companies. With the help of low-altitude economy, battery companies can penetrate cutting-edge technologies into more diversified fields, promote product performance upgrades, and significantly improve market competitiveness.
As the core component of eVTOL products, the performance and safety of the battery directly determine the terminal performance and application boundaries of eVTOL products. In terms of cell intrinsic safety, high energy density, long cycle, fast charging, and high discharge rate, eVTOL almost requires the battery cells to have comprehensive and extreme performance, and the current industry is still in the exploration stage for battery cell products that fully meet the needs of eVTOL.
At the same time, Xu Yan also mentioned that the Ministry of Industry and Information Technology and other four departments issued a notice to promote the mass production of 400Wh/kg aviation lithium battery products. At present, the energy density of battery cells in the industry is generally about 280Wh/kg, and there is still a certain gap with the target.
EVTank, a research institution, believes that the rise of the eVTOL industry has opened up new areas and created new growth momentum for the application of lithium batteries and next-generation battery technologies, such as all-solid-state batteries and lithium metal batteries.
The cylindrical battery route is promising
The battery packages currently used in the eVTOL market are diverse, and multiple routes are developed in parallel, with prismatic, pouch and cylindrical cells all having their own characteristics. Xu Yan said that in view of the diversity of battery performance requirements for eVTOL at different stages of development and application scenarios, BAK Battery has developed a forward-looking system technical plan from the three dimensions of model, structure and chemical system, which has the characteristics of high energy density, high power, high safety, fast charging and long cycle, and provides reliable power guarantee for the low-altitude economic market.
According to Xu Yan's analysis, the cylindrical shell has high strength, no deformation in the whole life cycle, and good structural stability; The cylindrical directional pressure relief capacity is good, the pressure relief area is large, and the heat spread of the whole package can be controlled after a single battery fires; The cylindrical battery has stronger applicability to high specific energy chemical systems, excellent product performance, and supports fast charging, high power, high energy and other characteristics. The cylindrical battery is flexible in packing, which can meet the needs of different application packs, and the grouping efficiency is significantly improved after the CTC design is adopted. There are multiple shapes and non-standardized products in the aircraft battery pack, and the cylindrical battery pack has a strong advantage in volume capacity.
Xu Yan added that for the eVTOL market, BAK Battery has a series of products that meet the needs of BAK Battery, and is also conducting targeted R&D and innovation. BAK all-tab cylindrical battery has the performance advantages of high energy density, high power, high safety, fast charging and long cycle, which will be able to effectively meet the demand for eVTOL cells.
The battery network understands that BAK battery is a pioneer in the global cylindrical lithium battery industry, with more than 20 years of experience in the research and development of cylindrical batteries, making full use of the advantages of the cylinder itself to develop products suitable for eVTOL. The all-tab technology route formed by cylindrical batteries effectively reduces internal resistance and improves performance such as power and cycle life through structural innovation.
Xu Yan introduced that BAK Battery's all-tab cell platform 2170-48B battery has both high capacity and high power performance, with an energy density of more than 270Wh/kg, a maximum continuous discharge rate of 8C, and a cycle life of more than 1000 times.
BAK battery all-tab 2170-55B battery cell has greatly improved energy density and power performance, with an energy density of 300Wh/kg, a maximum continuous discharge rate of 8C for all DoD, and can charge the power from 10% to 80% in 10 minutes, which is suitable for pure electric power eVTOL selection.
BAK battery all-tab 2170-25B battery cell is developed for eVTOL hybrid and emergency backup power system, which can provide more powerful continuous high power output, the maximum continuous discharge rate of all DoD reaches 24C, the power can be charged from 10% to 80% in 7 minutes, and the cycle life is more than 5000 times, which is suitable for hybrid eVTOL and is suitable for its emergency power system selection in extreme situations.
With the blessing of solid-state technology, the large cylindrical battery is expected to exceed 400Wh/kg by 2030 to meet the high-energy needs of different scenarios of low-altitude flight.
It is worth mentioning that BAK Battery is one of the earliest battery cell manufacturers in China to disclose the large cylindrical all-tab technology, and released the first large cylindrical related patent as early as 2020. Up to now, BAK has a total of nearly 100 large cylindrical patents, with comprehensive coverage of large cylindrical all-tab technology, and relevant patents in many fields related to battery structure, process and equipment.
Give new momentum to high-quality development
As an efficient, reliable and green power source for eVTOL and other low-altitude aircraft, lithium battery innovation is the key to building core competitiveness. Starting from the aspects of material system selection, battery structure design, and battery formula design, BAK battery carries out differentiated design, so as to achieve high energy density and high power product characteristics suitable for eVTOL.
Xu Yan said that the typical challenges of BAK batteries are gas production problems, under the high energy density system, the chemical reactivity of materials is enhanced, which brings more system instability problems, and puts forward high requirements for the system design of batteries, especially the stability design of electrolyte. BAK battery has 20 years of experience in electrolyte development and technology accumulation, and the above problems can be well solved through design adjustment.
Innovation is the core driving force of development! Xu Yan said that BAK Battery has achieved a number of domestic firsts in high energy density battery technology: it is the first to realize the mass production of high nickel and high silicon products, pioneers the application of carbon nanotubes to products to achieve high performance, and is also the first enterprise to mass produce cylindrical battery products with the highest energy density in China. The company is also the earliest battery company in China to use silicon anode materials, and is the first to realize the mass production of high-nickel-silicon system cells, and has now gone from one generation of silicon to three generations of silicon, with excellent fast charging performance.
Xu Yan pointed out that industrial development also needs to form closer coordination and resource sharing with upstream and downstream partners in the industrial chain to better meet the needs of the emerging hot market of low-altitude economy.
In order to promote the high-quality development of the low-altitude economic industry, Xu Yan put forward suggestions:
1. Strengthen policy guidance and support: The government should introduce more supportive policies to encourage technological innovation and industrial upgrading, and at the same time establish a sound legal system to ensure a safe and orderly industry development environment.
2. Promote industry-university-research cooperation: encourage exchanges and cooperation between enterprises, universities and research institutions, promote the rapid transformation and application of technological achievements, and form a deep integration of technological innovation chain and value chain.
3. Strengthen infrastructure construction: Accelerate the construction of infrastructure such as charging/battery swapping networks and air traffic management systems, so as to provide necessary conditions for the large-scale commercial operation of eVTOLs.
In view of the development of the low-altitude economy, Xu Yan put forward the main goals and specific measures of BAK battery technology breakthrough and product optimization, standardization and certification, cross-border cooperation and ecological construction.
In terms of technological breakthroughs and product optimization, we continue to invest in R&D to meet the application needs of eVTOLs, truly develop products that match the performance of eVTOLs, solve pain points, and achieve significant improvements in key indicators such as battery energy density, cycle life, fast charging and safety, so as to meet the stringent requirements of eVTOLs for batteries.
In terms of standardization and certification, we actively participate in the formulation of international and domestic battery standards, promote the standardization process of eVTOL batteries, ensure that products successfully pass various strict safety and performance certifications, and lay the foundation for large-scale applications.
In terms of cross-border cooperation and ecological construction, we will develop and cooperate with eVTOL manufacturers, air traffic management service providers, charging infrastructure developers, etc., to jointly build a complete low-altitude economic ecosystem, accelerate the process of technology commercialization, and fully cooperate with eVTOL manufacturers to promote the implementation of airworthiness certification and realize large-scale application (2025-2026) as soon as possible.
Xu Yan revealed that in the future, BAK Battery will continue to gain insight into new application fields, increase R&D investment, continuously improve the high-quality production capacity of battery cells, seize the golden window period of low-altitude economy, and accumulate more kinetic energy for the development of new quality productivity.
Conclusion: This year's government work report proposes to accelerate the development of new quality productive forces and continuously shape new momentum for development. Judging from the development status of the lithium battery market this year, the power battery and energy storage battery market is seriously involuted, opening up new application fields, creating new growth momentum, and the rise of a new track of low-altitude economy is opening up a new path for the battery industry. At the same time, like BAK Battery, enterprises that have been committed to building core competitiveness with innovation and have been deeply engaged in the field of lithium batteries for many years are seizing development opportunities in new scenarios and new tracks with practical actions, and using technological progress to make efforts for the scale and commercialization of the eVTOL industry.