The space power system, as the name suggests, is the battery component applied to the spacecraft, known as the "heart of the spacecraft", which plays a decisive role in ensuring the normal operation of the spacecraft。Once there is a problem with the space power system, the spacecraft will completely lose its ability to work。

　　Space power systems are so critical，But it's also the most problematic part of the spacecraft，In the special environment of space, high-intensity work and the difficulty of replacement are the biggest challenges，For spacecraft in low orbit，The battery module needs to meet the service life of 8 years，And for spacecraft in geosynchronous orbit，It is required to have a service life of more than 18 years。

　　At present, in the world, battery technology is still a short board restricting the overall level of spacecraft, and China also lacks independent research and development, stable and reliable space power system。

　　On January 8, 2019, the "Key Technology and Application of high-specific energy lithium-ion Battery" project of Professor Sun Kening's team at the School of Chemistry and Chemical Engineering of Beijing Institute of Technology was awarded the second Prize of the National Science and Technology Invention Award in the Great Hall of the People。Behind the award, is the team after 20 years of struggle, the Beijing Institute of Technology team with completely independent intellectual property rights of the innovation results, to achieve China's space power system in the specific energy and lightweight breakthroughs, so that China's space power system to achieve the technical level of leapfrog improvement。

Write "a blank sheet of paper" all over

　　"Nothing can go wrong with the power system!"In April 2004，Xichang Satellite Center launch site，Academician Sun Jiadong, the founder of "two bombs and one star" and the chief designer of China's lunar exploration project at the time, said so firmly，Sun Kening, who was a young teacher at the time, was deeply touched，He secretly determined to make his own contribution to China's space power system research。

　　In 1999, Sun Kening began to dabish in the field of space power system research, he knows that the needs of the country is the mission of scientists, which is also the original intention of his dedication to the field。"There are very few companies specializing in space power supply in the world, and China is still far behind foreign countries in terms of space power supply technology.。"Sun Kening recalled。

　　In the same year, Sun Kening began the research of aerospace power supply, and at this time in front of him can be described as "a blank sheet of paper".。The exploration of no reference and accumulation is doomed to be bumpy, and soon Sun Kning realized that nickel-metal hydride batteries have problems such as low specific energy and poor reliability, which can not meet the needs of spacecraft for high-performance power systems。Sun Kening is not discouraged, and will look to lithium-ion batteries with better performance。In 2005, the space power system research proposed by Sun Kening was approved, but it still faces various difficulties in the absence of mature equipment, commercial materials and process technology。

　　In 2009, Sun Kening came to Beijing Institute of Technology and became the leader of the energy electrochemical engineering direction of the school's chemical engineering and technology discipline。"Beijing Institute of Technology has a deep research foundation in the field of chemistry and chemical industry, and the research foundation is very good, and the school attaches great importance to the research field of emerging industries, so after coming to Beijing Institute of Technology, I feel like a fish in water.。"Sun Kening so introduced。Later, in the fertile soil of the Beijing Institute of Technology, Sun Kening led the team to focus on lithium-ion batteries, in-depth research on electrode materials, diaphragm materials, manufacturing processes, and other aspects, and made continuous breakthroughs to form research advantages。

Sun Kening chaired the China-UK Young Scholars Seminar on Advanced Technologies for Sustainable Energy in Urban Transport

　　After 20 years of intensive research，Sun Kening's team has 23 patents with completely independent property rights in the field of space power systems，He has published more than 50 papers of international influence，To promote the production of "high specific energy, high reliability, lightweight" space power system，Sun Kening has also been named China's most Cited Scholar (Energy) by Elsevier for five consecutive years.。

The "Youth Army" fighting hard

　　"Our team is young, nine teachers, average age 37, the overall atmosphere is very open and inclusive。Sun Kening talked about his team, full of pride。In the "light up" of China's spacecraft power system, the "youth Army" led by Sun Kening is not only full of energy, but also full of innovative thinking。"Look up at the stars and always be curious。This is a philosophy that Sun Kening often shares with his team。

　　"I think the pragmatic quality of Beijing Institute of Technology is very attractive to me, so I came after graduation, and found like-minded partners in the team, so that I feel that there is a lot of room for development.。Wang Zhenhua, the young teacher in the team, graduated from the Harbin Institute of Technology in 2009, majoring in electrochemistry, and came to the team to engage in space battery research for ten years。

　　As the earliest team member, Wang Zhenhua witnessed the team's achievements in winning the Beijing Key Laboratory of Chemical Electricity and Green Catalysis, the Innovation Team of the Ministry of Education of Electrochemical Key Technology and Chemical Power Supply, the Ministry of Education Award, and the National Award。But behind the remarkable achievements, it is the hard work and struggle all the way。

　　"Testing batteries is not the same as testing other things, in order to measure the performance of batteries in a timely manner, some initial research can only rely on manual follow-up inspection.。The man has to follow the machine, and when does the machine stop and we follow the test。It is also common to live in an enterprise, test battery parameters at three in the morning, and continue to work at seven in the morning。Wang Zhenhua said so。

　　To make the Chinese people's own space power supply, Sun Kening's research is not just a theoretical breakthrough, he wants real products。With this concept, the team from the theoretical basis, technical route to product development, every step to consider the engineering needs, but this also puts higher requirements on the team。

　　The assembly of the space power system must be completed in a fixed space, once heaven, "must not make mistakes", this strict standard is the basic requirements of the space power system。In the face of stringent standards, power engineering can only face the most macro requirements such as size, energy, weight, which is always a great test for the team。

　　"No experiments do not believe, no verification is not scientific", this is Sun Kening team teachers and students often hang on the words, it is with this "drill", the team from the "zero foundation", build their own equipment, synthetic materials, began to explore the spacecraft power "made in China"。"Since we are studying the technical shortcomings of the country, we must overcome difficulties and do a good job!"

Train students to be 'smart'

Sun Kening teaches the course "Power Supply Technology" to students

　　"Know the big picture and be bright。Know the needs, clear direction。Know the difficulties, know the details。Know the ability, know the way。This is Sun Kening's request to the students。Sun Kening, who has constantly made breakthroughs in scientific research, always regards cultivating excellent students as an important component of team achievements。He also asked students to have two "brushes" : one is to aim at the international frontier and innovate basic research;Second, docking national needs and focusing on engineering applications。

　　"I entered the team to study for a PhD in 2014, and began to choose high-capacity cathode materials for lithium-ion batteries as my research direction in 2015。Referring to why he chose to come to Sun Kning's team, doctoral student Lu Chengyi said frankly: "The label is clear, the direction is clear, and Teacher Sun has been committed to battery research and has been deeply cultivating the field of energy.。Only long-term research can make scientific research deeper and bigger, and blindly follow the trend has no future, Teacher Sun set an example for us to learn。”

Lu Chengyi took a photo with his supervisor Sun Kening after finishing his doctoral dissertation defense

　　Lu Chengyi's research focuses on the development of cathode materials for high-performance lithium-ion batteries, aiming to improve the specific discharge capacity and cycle rate of lithium-ion single batteries。It is thanks to the tutor Sun Kening's careful guidance, so that Lu Chengyi harvest is not small。

　　"The lithium iron phosphate electrode material is widely used in lithium-ion batteries because of its relatively high safety, but its defect is that the specific capacity is not too high。In an experiment, I accidentally found that the discharge capacity of lithium iron phosphate has been greatly improved。Teacher Sun did not let go of this accidental experimental result, but encouraged and guided me to further observe and think about the mechanism。Finally, we repeatedly tested, through the construction of nitrogen and oxygen free radicals to improve its complex energy, to achieve the specific capacity of lithium iron phosphate "overcapacity"。At that time, only a few papers in the world talked about how to achieve the "supercapacity" of lithium iron phosphate, and our results can be said to open up a new direction。Lu Chengyi through the "inorganic + organic" process composite, making the specific capacity of lithium iron phosphate reached 190mAh/g, which not only exceeds the highest actual specific capacity of 160 mAh/g that can be achieved in the industry at that time, but also breaks through the theoretical specific capacity level of 170 mAh/g。

　　From the ordinary preparation to find the problem, so as to prove the conjecture, and then actively optimize, and finally verify the results, such a complete scientific research closed loop, Sun Kening for themselves and students, are required not only complete and indispensable, but also must take every step to go very solid。

　　"I think the most interesting thing is the experimental skills competition once a semester。Each of us will have 5 opportunities, through 5 preparations, come up with the best data to compete, and who has the best data among all of them is the champion。In this way, we not only improve our hands-on skills, but sometimes we get a lot of inspiration。Team student Xu Chunming talked about this internal competition always with relish。And such competition is only a microcosm of Sun Kening's heuristic training of talents. Whether it is the young teachers in the guidance group or the graduate students in the research group, Sun Kening attaches great importance to inspiring thinking。"Mr. Sun likes to exchange ideas and share his research experience, but he never instills it into us。Whether it is preparing lessons or applying for projects, Teacher Sun will discuss the framework with everyone, and then help us revise the first draft and the second draft very carefully.The final draft, when the draft is full of his handwriting, this process, but also let us often learn often new feeling。Team teacher Sun Wang said so。

　　Do not forget the original heart, for China's "light of deep space" bright long stay, keep in mind the mission, with the struggle to build a new era。"This is what our scientific researchers should do, and it is what every Beili worker needs to do, so we did it.。On the occasion of winning the national award, Sun Kening said。