Innovating lithium iron phosphate power battery engineering science to promote technological change in the new energy industry
In the development wave of the new energy industry, power batteries play a pivotal role. Since 2004, the team of Professor Ma Zifeng of the School of Chemistry and Chemical Engineering of Shanghai Jiaotong University has been supporting BYD, Sinopoly Battery, Jiangsu Leneng, ZTE Paineng and other enterprises under the continuous support of the National 973 Program and the National Natural Science Foundation of China. Years of efforts have built a lithium iron phosphate power battery technology system with independent intellectual property rights, which has been widely used in new energy vehicles and energy storage engineering systems. On January 8, the 'Key Technologies of Lithium Iron Phosphate Power Battery Manufacturing and Its Application Process' completed in cooperation with BYD and other units won the second prize of the 2018 National Science and Technology Progress Award.
After 15 years of industry-university-research cooperation, China has become the world's largest country in the manufacture and application of lithium iron phosphate batteries; the lithium iron phosphate power battery developed by Ma Zifeng’s team The technology continues to improve. This kind of power battery has been widely used in electric buses, electric logistics vehicles, and passenger cars. The electric buses powered by lithium iron phosphate are also exported to the United States, Japan, the United Kingdom, Europe and Oceania, and are well received. .
Not only that, the user-side energy storage power station using lithium iron phosphate power batteries has been operating stably for many years, and has been recognized by the US market and relevant European authorities. Won the '2015 North American Centralized Energy Storage Innovation Award' and the 2017 Global Energy Storage 'TechDriver' award from the German Clean Technology Institute.
Since Plante invented lead-acid batteries, power batteries have undergone 160 years of development. The first motor vehicle in the world was an electric vehicle powered by lead-acid batteries, but due to its low energy density and short cruising range, it was quickly surpassed by internal combustion engine vehicles. In the 21st century, due to the reduction of global petroleum resources and the increasing environmental pressure, the development of green and environmentally friendly new energy vehicles has become a hot spot for technological changes in the automotive industry.
Lithium batteries have been successfully used in consumer electronic products such as mobile phones and notebook computers due to their high energy density and light portability. With the development of emerging industries such as new energy vehicles, renewable energy and smart grids, the research and development of high-safety, long-life, high-capacity and low-cost power lithium batteries has become the research frontier. Cathode materials are the basis of battery development. Lithium battery cathode materials mainly include lithium manganate, lithium iron phosphate and ternary materials. Among them, lithium iron phosphate is an internationally recognized positive electrode material for power lithium batteries that can be continuously developed.
In 1996, lithium iron phosphate was used in power lithium battery research. In order to reduce production costs and reduce pollution in the production process, Ma Zifeng's team proposed a new synthesis reaction of lithium iron phosphate and prepared a new structure of cathode material. In 2004, Professor Ma Zifeng's team carried a new method for the synthesis of lithium iron phosphate, and cooperated with Zhejiang Hengdian East Magnetics to develop lithium iron phosphate cathode materials.
In 2007, Ma Zifeng, as the chief scientist, presided over the National 973 Program 'Research on Basic Scientific Issues of Low-cost and High-density Power Storage Systems for Electric VehiclesThe industrialization of batteries has injected new vitality. In 2012, under the funding of the 'Boost Program' of the Shanghai Science and Technology Achievement Transformation Promotion Association, Shanghai Jiaotong University transferred the overall patent for the new technology of lithium iron phosphate synthesis invented by Ma Zifeng and others, and established the Sinopoly Battery Research Institute to develop lithium iron phosphate batteries. The technology has been widely promoted, and has been authorized and licensed to many companies for implementation, and a batch of new patented technologies have been developed. In 2014, under the special funding of Jiangsu Enterprise Innovation and Achievement Transformation, Ma Zifeng served as the chief expert to build a 25,600 tons/year nano-lithium iron phosphate production line in Jiangsu Leneng. The products are used in many well-known battery companies such as BYD and CATL .
The Ma Zifeng team also invented a coating solution configuration and coating method, proposed the corresponding process, optimized the technical parameters, and formed a super high magnification, Ultra-long cycle life nano lithium iron phosphate power battery and its new manufacturing method, and solve the problem of low temperature cold start and high rate of lithium iron phosphate battery.
Battery management system design is a very important part of the application of battery packs to electric vehicles and energy storage. How much power is left in the power battery system directly affects the car's cruising range. The amount of battery power can be described by the battery state of charge (SOC). SOC is a complex and dynamic process. Based on the analysis of battery reaction/transfer mechanism and operating characteristics, the team developed related technologies and established a new SOC estimation model. Compared with the international advanced indicators, the model’s estimation accuracy of the battery health status has increased by about 5 percentage points to 97%. In addition, the team also cooperated with BYD to develop a SOC estimation model based on rolling time domain optimization, which further improved the SOC estimation accuracy to 99%. Related theoretical results have been published in authoritative journals such as the Journal of the American Chemical Engineering Society and Chemical Engineering Science.
Ma Zifeng believes that with the continuous improvement and scientificization of the new energy automobile industry policy, it is foreseeable that lithium iron phosphate power batteries will be used in electric buses and large-scale transportation and logistics tools on a large scale. The energy storage system will play a long-term role to benefit mankind.
The reporter was informed that, including the 'Key Technologies of Lithium Iron Phosphate Power Battery Manufacturing and Its Application Process' project, at the 2018 National Science and Technology Awards Conference held on the same day, Shanghai Jiaotong University has a total of 10 achievements of the first completed unit to be commended, including 1 National Natural Science Second Prize, the first completer is Guan Xinping, 1 National Technological Invention Award, the first completer is Sun Baode, and the second class National Science and Technology Progress Award There are 8 awards, and the first finishers are Yang Jianmin, Ma Zifeng, Zhang Wenjun, Fan Xianqun, Wu Hao, Xia Qiang, Zhao Weilai and Fang Jingyuan.
