摘要
锂离子电池是能源领域的革命性创新,具有能量密度高、循环寿命长等优点,推动了新能源、新能源汽车等新兴产业的跨越式发展,并应用于卫星、无人机等国家战略领域,成为世界各国竞争的战略高地.锂离子电池的广泛应用不仅源于新兴能源材料的创新,还与制造工艺及装备技术的进步密不可分.极片制造作为生产锂离子电池最核心的过程,包括制浆、涂布、辊压三大关键工序,制造的正负电极构成了电化学反应载体和整个电池的核心.在电极制造中,多孔多组分电极微结构发生复杂的演化与定构过程,很大程度上决定了单体电池的能量密度、倍率特性等性能.本文分析极片制造中制浆、涂布和辊压技术进展与应用情况,重点讨论电极微结构在制造过程中的演化以及其对电池电化学性能的影响,旨在从“制造工艺-微结构-性能”之间的关系视角形成对电极微结构设计、材料制备、制造工艺的进一步认识,为研发高性能锂离子电池提供指导.
Since its commercialization in the 1990 s, the lithium-ion battery has been a huge success in the energy industry owing to its high energy density and long cycle life. They have been used in national strategic fields, such as satellites and unmanned aircraft, to promote a remarkable leap forward in new energy, new energy vehicles, and other emerging industries.Therefore, the development of lithium-ion batteries is a strategic high ground for competition among countries worldwide.The development and widespread use of lithium-ion batteries is driven by their high energy/power density, long cycle life, and low cost, which requires battery material innovation as well as advancements in manufacturing processes and equipment technology. Particularly, the power and energy storage applications require numbers of battery cells connected in series or parallel. High precision is required to ensure the consistency of the battery cell, to avoid module capacity loss and cycle life attenuation owing to the “shortboard effect,” and to ensure battery safety. Electrode manufacturing, which is the first critical process of lithium-ion battery production, consists of three critical steps: Mixing, coating, and rolling. The positive and negative electrode active materials, conductive agents, binders and solvents are mixed into slurry and coated on copper or aluminum foil. The positive/negative electrodes, which constitute the electrochemical reaction carrier and the battery’s core, are obtained after drying and roller compaction. The porous and multi-component electrode microstructure evolves and is constructed in a complex way during electrode manufacturing. The proportion of electrode slurry, mixing order, coating method, drying strategy, and rolling process can considerably affect the evolution of electrode microstructure, such as pore structure, active particle distribution and, conductive/bonding network. It also influences the lithium-ion battery’s electrochemical performance. Despite tremendous advances in high-energy-density materials,research on lithium-ion battery manufacturing lags, resulting in a large gap between laboratory and production scales. This requires an in-depth understanding of the manufacturing and the relationship between electrode microstructure evolution and battery performance.The advancement and application of cutting-edge slurry mixing, coating, and calendering technologies in electrode manufacturing are thoroughly reviewed in this paper. The evolution of electrode microstructure during manufacturing, in particular, and its impact on the battery’s electrochemical performance, are discussed in detail. Then, various novel electrode manufacturing techniques are summarized in terms of their significance and challenges, covering the innovations based on the current process(aqueous processing, simultaneous double-sided slot coating, multilayer co-coating and,multistage drying), dry processing(electron beam and ultraviolet curing forming, electrostatic dry-powder coating), threedimensional printing, and template-based methods. We aim to gain a better understanding of electrode structure design,material preparation, and manufacturing processes through the perspective of the “Manufacturing-MicrostructurePerformances” relationship and guide the development of high-performance lithium-ion batteries. Finally, perspectives on future developments toward accelerating electrode design and manufacturing process optimization are presented, including three main parts:(1) Developing the multiscale and whole-process simulation platform to connect the electrode manufacturing, microstructure, and battery performance;(2) constructing microstructure-controllable electrode manufacturing technology that is compatible with existing production infrastructure;and(3) researching the microstructure evolution of the post-lithium-ion battery manufacturing.
作者
李茂源
张云
汪正堂
谭鹏辉
刘兴鹏
张道琦
李光
解晶莹
周华民
Maoyuan Li;Yun Zhang;Zhengtang Wang;Penghui Tan;Xingpeng Liu;Daoqi Zhang;Guang Li;Jingying Xie;Huamin Zhou(State Key Laboratory of Materials Processing and Die&Mould Technology,School of Materials Science and Engineering,Huazhong University of Science and Technology,Wuhan 430074,China;Shenzhen Haoneng Technology Co.,LTD.,Shenzhen 518122,China;Shenzhen BYD Lithium Battery Co.,LTD.,Shenzhen 518116,China;Tianjin Lis hen Battery Co.,LTD.,Tianjin 300392,China;Hubei Yiwei Power Co.,LTD.,Jingmen 448124,China;State Key Laboratory of Space Power Supply Technology,Shanghai Institute of Space Power Supply,Shanghai 200245,China)
出处
《科学通报》
EI
CAS
CSCD
北大核心
2022年第11期1088-1102,共15页
Chinese Science Bulletin
基金
国家自然科学基金(52175317)资助。
关键词
锂离子电池
电极制造
制浆
涂布
辊压
电极微结构
lithium-ion battery
electrode manufacturing
slurry mixing
coating
calendaring
electrode microstructure
