Cheaper and safer sodium ion batteries may become a new track for energy overtaking in China.
The core of the new round of energy revolution is renewable energy generation and large-scale energy storage. Among many electrochemical energy storage technologies, sodium ion battery is one of the ideal choices for large-scale energy storage because of its rich resources, low cost, high safety, high conversion efficiency, flexibility, convenience, easy integration, fast response and maintenance-free.
— — Hu Yongsheng, researcher of Institute of Physics, Chinese Academy of Sciences, founder and chairman of Zhongke Haina.
Intern reporter Yu Ziyue
Recently, high-tech enterprises such as Zhongke Haina Technology Co., Ltd. (hereinafter referred to as Zhongke Haina) and Huayang New Materials Technology Group Co., Ltd. hatched by Institute of Physics, Chinese Academy of Sciences signed a contract with the Management Committee of Shanxi Transformation Comprehensive Reform Demonstration Zone to build a production line for anode and cathode materials of sodium ion batteries with an annual output of 2,000 tons in Taiyuan.
On February 20th, Hu Yongsheng, a researcher at the Institute of Physics of Chinese Academy of Sciences and the founder and chairman of Zhongke Haina, said in an interview with the Science and Technology Daily reporter that China’s sodium ion batteries are in the forefront of the world in terms of technology research and development such as material system and battery comprehensive performance, as well as in terms of industrialization speed, demonstration application, patent layout and standard formulation, and have already had the first-Mover advantage.
New energy nova is accelerating on the road of industrialization.
The development of fossil energy such as coal, oil and natural gas has led to the rapid development of human society, and the progress of modern non-fossil energy is also triggering a new round of energy revolution. Who will be the protagonist this time?
The voice of lithium-ion batteries is very high. However, when lithium-ion batteries are widely used in more and more fields in China, an unavoidable problem is becoming more and more worrying — — China’s lithium resources are highly dependent on imports. It is necessary to develop energy storage battery technology which does not depend on rare resources and has low cost.
Sodium ion battery, which is closest to lithium ion battery technology, has begun to emerge. In recent years, related achievements with independent intellectual property rights have emerged continuously. Intelligent electric bicycles, low-speed electric vehicles, home energy storage cabinets, energy storage power stations and sightseeing electric vehicles in parks/scenic spots with sodium ion batteries as the "heart" have come out one after another, and many achievements have been released for the first time in the world.
In the "Top Ten Scientific Progress in China in 2020" recently organized by the High-tech Research and Development Center of the Ministry of Science and Technology, sodium ion battery research was selected as 30 candidate results.
As a new star of new energy, sodium ion battery is accelerating on the road of industrialization, or it will become an opportunity for China to lead a new round of energy revolution.
"Sodium" attracts talents to make up for the lack of "lithium"
Globally, the distribution of lithium resources is extremely uneven, with about 70% distributed in South America. Available data show that at present, 80% of lithium resources in China depend on imports.
"Although lithium-ion batteries have become ‘, which accounts for 80% of the global electrochemical energy storage scale market; Absolute first brother ’ However, the scarcity of its resources and high cost have led to the large-scale development of its industry facing the ceiling. " Hu Yongsheng said in an interview with the Science and Technology Daily reporter.
How to solve the problem? It is urgent to find a cheap substitute.
Therefore, sodium ion batteries with the same working principle and similar battery components as lithium ion batteries have ushered in a great development opportunity.
Similar to lithium-ion batteries, sodium ion batteries rely on the reversible stripping and embedding of sodium ions between positive and negative electrodes to realize the storage and output of electric energy.
Sodium resources are extremely abundant in the earth’s crust, and the abundance of the earth’s crust is more than 1000 times that of lithium. Sodium ion batteries have shown significant advantages in cost. If the same energy is stored, the cost will be about 30% less than that of lithium ion batteries. Because of the similar battery structure, most of the existing lithium ion battery production equipment can be directly put into the production of sodium ion batteries, which further improves the cost control.
In the process of industrialization, low price is very important, but good quality is more important. Hu Yongsheng told the Science and Technology Daily reporter that the comprehensive performance of sodium ion batteries shows multiple advantages.
With the deepening of research, researchers found that sodium ion batteries have good power characteristics, wide temperature range adaptability, safety performance and no discharge problems. In addition, both the anode and cathode of the sodium ion battery can adopt aluminum foil current collectors, which can further improve the energy density of the sodium ion battery and make the sodium ion battery move towards the direction of low cost, long life, high specific energy and high safety.
Hu Yongsheng, for example, now commonly used mobile phone lithium-ion batteries can be fully charged in about one hour, while sodium-ion batteries can be fully charged in ten minutes or even less. It is frequently reported that lithium-ion batteries go on strike at low temperature in winter, while the discharge characteristics of sodium-ion batteries are still very good in the environment as low as -30℃ and as high as 80℃, which shows that they are environmentally friendly, very "sturdy" and can withstand tossing. "We have done experiments, using a steel needle to pierce the sodium ion battery, artificially shorting it, and found that there was no fire or explosion."
Cheap, "sturdy" and safe, sodium ion batteries are likely to become an important supplementary technology for lithium ion batteries in the future.
Breaking the technical bottleneck and broadening the application scope
Positive electrode, negative electrode and electrolyte are the three elements of sodium ion battery. Among them, most cathode materials face bottlenecks such as poor stability, short cycle life and high cost.
In order to solve these problems, the research team of Hu Yong Sheng bypassed the high-priced elements such as nickel and cobalt, which are commonly used as cathode materials for lithium-ion batteries, and used common elements such as copper, iron and manganese, and developed a layered oxide cathode material system for sodium-ion batteries with low cost, high stability and long service life.
Previously, the team cooperated with international scholars and published the research results on the cathode materials of sodium ion batteries for the first time in Science magazine.
Relying on the sodium ion battery technical team of the Institute of Physics, Zhongke Haina was established in 2017, becoming the first high-tech enterprise in China to focus on the R&D and production of sodium ion batteries. At present, Zhongke Haina has been financed twice, totaling 58 million yuan, for pilot technology development, and has built a 100-ton pilot test line for anode and cathode materials of sodium ion batteries and a million ampere-hour battery core line, and developed many products, such as soft bags, aluminum shells and cylindrical batteries, with energy density of 100— Between 150 watt-hours per kilogram, it is more than 3 times that of lead-acid battery, and its cycle life is more than 4500 times. Not long ago, the Science and Technology Cooperation Center of Beijing Municipal Science and Technology Commission organized an expert group to accept the project it undertook. The evaluation given by the expert group was that the relevant technical indicators reached the international leading level.
At the end of 2017, the team developed a 48V/10Ah sodium ion battery pack for electric bicycles; In 2018, the team developed a 72V/80Ah sodium ion battery pack and launched the world’s first sodium ion battery electric vehicle.
It is reported that the team has obtained more than 20 patents authorized by China on key materials such as positive electrode, negative electrode, electrolyte, additives and adhesives (some patents have been authorized by the United States, Japan and the European Union), and published more than 100 papers in academic magazines such as Science and Nature, which have been cited for more than 10,000 times.
These scientific research achievements will also play the role of engines, and will be transformed in a series of incubation enterprises such as Zhongke Haina, providing inexhaustible power for the commercial development of sodium ion batteries.
High hopes are placed on scale energy storage.
Climate change is a global problem facing human beings, so China has put forward the goal of carbon neutrality in 2030 peak carbon dioxide emissions and 2060, which also means that China’s economy and society will usher in a comprehensive low-carbon change.
In 2017, Chen Liquan, an academician of China Academy of Engineering, put forward the idea of "electric China". This coincides with China’s advocacy of building a global energy internet to meet global power demand in a clean and green way.
So, here’s the problem.
Solar energy and wind energy are the main renewable new energy sources to generate electricity, but they are random, intermittent and fluctuating. Solar panels can generate electricity in sunny days and during the day, but on cloudy days and at night, they "stop eating". Wind power generation is also closely related to wind power and weather. However, nowadays, we can’t leave electricity for a moment, and we can’t stand the days when electricity is only available when the weather is "awesome".
There is an urgent need for large-scale energy storage devices, mainly energy storage power stations, to store surplus electric energy and use it when power generation is insufficient to ensure a stable supply of electricity.
At present, the lithium-ion battery is the "first brother" in the energy storage demonstration power station. However, due to various restrictions mentioned above, the lithium-ion battery cannot support the two huge markets of electric vehicles and large-scale energy storage at the same time. Therefore, Academician Chen Liquan and researcher Hu Yongsheng have high hopes on the sodium-ion battery.
In 2019, Zhongke Haina launched the world’s first 100 kWh sodium ion battery energy storage power station, which realized the demonstration application of sodium ion battery in large-scale energy storage for the first time.
"peak carbon dioxide emissions and carbon neutrality are China’s solemn commitments and opportunities to lead the third energy revolution." Hu Yongsheng pointed out that the core of the new round of energy revolution is renewable energy power generation and scale energy storage. At present, the former is close to maturity, while the latter is still developing. Among many electrochemical energy storage technologies, sodium ion battery is one of the ideal choices for scale energy storage because of its rich resources, low cost, high safety, high conversion efficiency, flexibility, convenience and easy integration, fast response speed and maintenance-free.
Due to the huge energy storage market and industrial demand, combined with China’s perfect lithium-ion battery industry chain, sodium ion batteries have already had the conditions to take the lead in realizing industrialization and commercialization in China.
"I believe that with the strong support of the top-level planning and related policies of governments at all levels in China, with the collaborative innovation of production, learning and research and the promotion of social capital, sodium ion batteries will surely play an important role in achieving the goals of peak carbon dioxide emissions and carbon neutrality." Hu Yongsheng said.