Wang Mingzhan, Yang Hao, Wang Kexin, Chen Shulin, Ci Haina, Shi Liurong, Shan Jingyuan, Xu Shipu, Wu Qinci, Wang Chongzhen, Tang Miao, Gao Peng, Liu Zhongfan, Peng Hailin
Center for Nanochemistry, Beijing Science and Engineering Center for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, People's Republic of China.
Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, People's Republic of China.
Nano Lett. 2020 Mar 11;20(3):2175-2182. doi: 10.1021/acs.nanolett.0c00348. Epub 2020 Feb 28.
At the mesoscopic level of commercial lithium ion battery (LIB), it is widely believed that the poor contacts between current collector (CC) and electrode materials (EM) lead to weak adhesions and large interfacial electric resistances. However, systematic quantitative analyses of the influence of the interfacial properties of CC are still scarce. Here, we built a model interface between CC and electrode materials by directly growing hierarchical graphene films on commercial Al foil CC, and we performed systematic quantitative studies of the interfacial properties therein. Our results show that the interfacial electric resistance dominates, i.e. ∼2 orders of magnitude higher than that of electrode materials. The interfacial resistance could be eliminated by hierarchical graphene interlayer. Cathode on CC with eliminated interfacial resistance could deliver much improved power density outputs. Our work quantifies the mesoscopic factors influencing the battery performance and offers practical guidelines of boosting the performance of LIBs and beyond.
在商用锂离子电池（LIB）的介观层面，人们普遍认为集流体（CC）与电极材料（EM）之间的不良接触会导致附着力弱和界面电阻大。然而，关于集流体界面特性影响的系统定量分析仍然很少。在此，我们通过在商用铝箔集流体上直接生长分级石墨烯薄膜，构建了集流体与电极材料之间的模型界面，并对其中的界面特性进行了系统定量研究。我们的结果表明，界面电阻占主导地位，即比电极材料的电阻高约2个数量级。分级石墨烯中间层可以消除界面电阻。具有消除界面电阻的集流体上的阴极可以提供显著提高的功率密度输出。我们的工作量化了影响电池性能的介观因素，并为提高锂离子电池及其他电池的性能提供了实用指导。
