On November 16, the technology achievement appraisal meeting for the "Key Technologies for the Large-Scale Engineering Application of Second-Life Utilization of Power Batteries" was held in Beijing, organized by the China Electrotechnical Society. Experts from the appraisal committee, representatives from the Chinese Society for Electrical Engineering (CSEE), and over 50 participants from organizations such as China Huadian Inner Mongolia Energy Co., Ltd., Tsinghua University, Beijing Institute of Technology, China Huadian Science and Technology Group Co., Ltd., and Yunchu New Energy Technology Co., Ltd., attended the meeting. After inquiries, responses, and discussions, the appraisal committee unanimously concluded that the project had achieved "multiple breakthrough results," had "significant socio-economic and ecological effects," and that the project as a whole had "reached an internationally leading level."

Appraisal meeting

The appraisal committee was chaired by Academician Zhou Xiaoxin from the China Electric Power Research Institute. Yu Zhenhua, Executive Vice Chairman of the Zhongguancun Energy Storage Industry Technology Alliance, served as vice chairman. Committee members included: Zhang Dongxia, professorate senior engineer from China Electric Power Research Institute; Yuan Yubo, professorate senior engineer from State Grid Jiangsu Electric Power Company Electric Power Research Institute; Zhao Wei, professorate senior engineer from the Southern Grid Digital Grid Research Institute; Xu Long, professorate senior engineer from the Hohhot Branch of the Chinese Academy of Agricultural Mechanization Sciences; Xu Jiabin, professorate senior engineer from Shandong Electric Power Engineering Consulting Institute; Chen Dongxu, Senior Engineer from China Tower Corporation Limited; and Yuan Wenjing, Senior Engineer from Beijing Automobile Research Institute Co., Ltd.

The meeting also invited officials from the Energy Bureau of Inner Mongolia Autonomous Region, Zhang Chengjie, Party Committee Member and Deputy General Manager of China Huadian Inner Mongolia Energy Co., Ltd., Lin Feng, Director of the Science and Technology Information Department, Professor Xiao Xi, Vice Dean of Tsinghua University Graduate School, Professor Cheng Lin, Deputy Director of State Key Laboratory of New Type Power System Operation and Control, Tsinghua University, Professor Li Li from the College of Materials Science and Engineering at Beijing Institute of Technology, Dr. Li Yanhong, Chief Engineer of the Energy Storage Branch of China Huadian Science and Technology Group Co., Ltd., and Gao Hong, General Manager of Yunchu New Energy Technology Co., Ltd.

Leaders of completion units delivered speeches

After the meeting began, Zhang Chengjie, Deputy General Manager, and Professor Xiao Xi delivered speeches on behalf of the completion units.

Technical Report by Researcher Ci Song from Tsinghua University

Researcher Ci Song from the Department of Electrical Engineering and Applied Electronics (EEA) at Tsinghua University, Assistant Researcher Zhou Yanglin from the State Key Laboratory of New Type Power System Operation and Control at Tsinghua University, Assistant Researcher Zhang Shixu, Associate Researcher Tian Peigen, and Director of the Production Technology Department at China Huadian Inner Mongolia Energy Co., Ltd. Xiao Shengzhong presented technical reports, work progress reports, socio-economic benefit analysis reports, technology updates, and application validation reports. They provided a comprehensive overview of the project's research process, key technological achievements, demonstration applications, and socio-economic benefits.

Group photo of appraisal committee members and key project contributors

With the rapid development of new energy vehicles, the reuse of retired power batteries has become a pressing issue. The residual capacity of retired power batteries can support low-rate charging and discharging scenarios, holding significant potential and value in applications such as new energy power generation and energy storage systems, industrial and commercial energy storage, backup power for base stations, and emergency power supplies. However, the performance degradation of retired power batteries is uneven, making it difficult to ensure the overall performance, safety, and economic viability of second-life utilization battery storage systems in terms of performance evaluation and consistency management, efficient sorting and reorganization, safety management, and economic operation.

The project achievements are based on the "Key Technologies for the Large-Scale Engineering Application of Second-Life Utilization of Power Batteries" project, which was part of Inner Mongolia Autonomous Region's 2020 Major Science and Technology Project on "Large-Scale Energy Storage." The project leader was Researcher Ci Song. The project passed a comprehensive performance evaluation organized by the Inner Mongolia Autonomous Region Science and Technology Achievement Transformation Center on November 6, 2024, with expert opinions indicating good results. The project team includes China Huadian Inner Mongolia Energy Co., Ltd., Tsinghua University, Beijing Institute of Technology, Inner Mongolia University of Technology, China Huadian Science and Technology Group Co., Ltd., China Huadian Electric Power Research Institute Co., Ltd., State Grid Nanjing Automation Co., Ltd., China Electric Power Research Institute Co., Ltd., Yunchu New Energy Technology Co., Ltd., and Beijing Weilan New Energy Technology Co., Ltd., forming a collaborative team involving industry, academia, and research.

Through research and practice, the project team has achieved a series of results in areas such as health state and residual value assessment of retired power batteries, rapid sorting and reorganization, thermal safety integration and control, safe and economic operation, and commercial application models. The project has been demonstrated at Baotou Bayin New Energy Base of China Huadian Inner Mongolia Energy Co., Ltd., where the world’s largest single-point 10MW/34MWh second-life utilization power battery energy storage system demonstration project has been built. This project effectively verified the theoretical foundations, key technologies, and application models in the large-scale application of second-life utilization power batteries, contributing to China’s green energy transition.

The research outcomes are integrated into a digital energy exchange system for the module-level full-package utilization of retired power batteries. This system maintains the advantages of low cost and low loss in large-scale applications of retired power batteries while significantly improving thermal management and high reliability, marking an important breakthrough in the technology of large-scale engineering applications for second-life utilization of power batteries. The project team will continue to deepen industry-academia-research cooperation, strengthen close ties with industry enterprises, promote the transformation of more scientific research achievements into practical productivity, and contribute more to China’s green, low-carbon development and the construction of an innovative country.