分层式结构对干法电极性能的影响  

Effect of layered electrode structure on the performance of dry electrode

作　　者：胡洪瑞 班宵汉 刘富亮 袁再芳 刘江涛 HU Hongrui;BAN Xiaohan;LIU Fuliang;YUAN Zaifang;LIU Jiangtao(State Key Laboratory of Advanced Chemical Power Sources,Guizhou Meiling Power Source Co.,Ltd.,Zunyi 563003,Guizhou,China)

机构地区：[1]贵州梅岭电源有限公司,特种化学电源国家重点实验室,贵州遵义563003

出　　处：《电池》2025年第2期319-323,共5页Battery Bimonthly

摘　　要：相比于传统湿法工艺,干法电极制备工艺具备制造成本低、生产效率高、极片负载量高等优点。高负载量干法极片的厚度较厚,限制了极片离子/电子传输速率,导致倍率性能较差。采用自支撑膜热压复合的方法,制备导电剂含量与孔隙率呈梯度式分布的分层式干法极片,并对比分层式极片与传统干法极片的电化学性能差异。分层式极片结构设计优化了干法电极的离子/电子传输速率,提升了电极的电化学性能。相较于传统干法电极,分层式干法极片电阻率降低了11.62%,电荷转移阻抗降低了47.8%。分层式干法极片制备的扣式电池以0.5 C在3.0~4.2 V循环200次,容量保持率为87.44%,10.0 C放电比容量为0.2 C时的72.23%。Compared with traditional wet process,the dry electrode preparation process has the advantages of low manufacturing cost,high production efficiency and high electrode loading capacity.The thickness of the high load dry electrode is relatively thick,which limits the ion/electron transfer rate of the electrode and leads to poor discharge rate capability.The method of self-supporting membrane hot pressing composite is adopted to prepare layered dry electrode with gradient distribution of conductive agent content and porosity,the difference of electrochemical performance between layered electrode and traditional dry electrode is compared.The layered electrode structure design optimizes the ion/electron transport rate of the dry electrode and improves the electrochemical performance of the electrode.Compared with traditional dry electrodes,the layered dry electrode has a reduced resistivity of 11.62%and a reduced charge transfer impedance of 47.8%.The capacity retention rate of the button cell prepared by layered dry electrode after 200 cycles at 0.5 C in 3.0-4.2 V is 87.44%,the discharge specific capacity at 10.0 C is 72.23%of the one at 0.2 C.

关 键 词：锂离子电池 干法电极 分层式电极 钴酸锂 厚电极 

分 类 号：TM912.9[电气工程—电力电子与电力传动]