Preparation and characterization of flexible lithium iron phosphate/graphene/cellulose electrode for lithium ion batteries

Yan Wang; Zhen-Yu He; Yao-Xuan Wang; Cong Fan; Chen-Ren-Lang Liu; Qi-Ling Peng; Jin-Ju Chen; Zhe-Sheng Feng

doi:10.1016/j.jcis.2017.10.042

Preparation and characterization of flexible lithium iron phosphate/graphene/cellulose electrode for lithium ion batteries

J Colloid Interface Sci. 2018 Feb 15:512:398-403. doi: 10.1016/j.jcis.2017.10.042. Epub 2017 Oct 12.

Authors

Yan Wang¹, Zhen-Yu He¹, Yao-Xuan Wang¹, Cong Fan¹, Chen-Ren-Lang Liu¹, Qi-Ling Peng², Jin-Ju Chen¹, Zhe-Sheng Feng³

Affiliations

¹ State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, PR China.
² Institute of Chemical Materials, China Academy of Engineering Physics, Mianyang 621999, PR China.
³ State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, PR China. Electronic address: fzs@uestc.edu.cn.

PMID: 29096099
DOI: 10.1016/j.jcis.2017.10.042

Abstract

In this work, a free-standing flexible composite electrode was prepared by vacuum filtration method with LiFePO₄, graphene and nanofibrillated cellulose (NFC). Compared with the pure LiFePO₄ electrode, the resulting flexible composite (LiFePO₄/graphene/NFC) electrode showed excellent mechanical flexibility, and possessed an enhanced initial discharge capacity of 151 mA h/g (0.1 C) and a good capacity retention rate with only 5% loss after 60 cycles due to suitable electrolyte wettability at the interface. Furthermore, the NFC and graphene formed a three-dimensional conductive framework, which provided high-speed electron conduction in the composite and reduced electrode polarization during charging-discharging processes. Moreover, the composite electrode could endure bending tests up to 1000 times, highlighting preferable mechanical strength and durability. These results demonstrated that the as-fabricated electrodes could be applied as flexible electrodes with an embedded power supply.

Keywords: Composite materials; Energy storage and conversion; Flexible electrodes; Graphene; Interface; Lithium ion batteries; Nanofibrillated cellulose.