Topological design of ultrastrong MXene paper hosted Li enables ultrathin and fully flexible lithium metal batteries

• Published in: Nano energy Vol. 74; p. 104817
• Main Authors: Wang, Cao-Yu, Zheng, Zi-Jian, Feng, Yong-Qiang, Ye, Huan, Cao, Fei-Fei, Guo, Zai-Ping
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.08.2020
• Subjects: Flexible devices; Lithium metal anodes; Lithium metal batteries; Ti3C2Tx MXene; Topological structure; Lithium metal batteries; Topological structure; Flexible devices; Ti3C2Tx MXene; Lithium metal anodes
• ISSN: 2211-2855
• DOI: 10.1016/j.nanoen.2020.104817

Ultrathin Li metal anode with a thickness of <30 μm in combination with state-of-art cathodes could promise high-energy lithium metal batteries (LMBs). Here, we report a facile spin steaming technology to design the topological structures of Ti3C2Tx MXene film as Li host by mixing a trace of cellulose nanofiber (CNF). The interlocked topological microstructure between MXene sheets and microspheres-forming assisted by CNF contributes greatly to enhanced mechanical strength and flexibility of the resultant MXene@CNF film. More importantly, the MXene sheets with abundant Li nucleation sites shows a desirable affinity for Li. As a result, a flexible, ultrathin (~25 μm), and self-supporting MXene@CNF/Li composite anode without rampant Li dendrites, and with favorable cycling stability with high real capacity of Li is realized. The as-obtained hybrid Li anode matches with flexible self-supporting LiFePO4/cellulose nanofiber (LFP@CNF) cathodes to construct fully flexible LMBs with high specific capacity and outstanding stability. A Li composite anode that features ultra-thin size, flexibility, and is self-supporting is realized by encaging Li into MXene film. Benefitting from its intrinsic surface characteristic and self-formed topological structure of MXene, the Li anode demonstrates uniform Li plating/stripping. A fully flexible cell based on the Li composite anode in combination with a flexible cathode exhibits long service-life. [Display omitted] •A flexible, ultrathin, and self-supporting MXene film with topological structure is constructed.•An interlocked topological microstructure between MXene sheets and microspheres-forming assisted by CNF is realized.•The resultant film exhibits enhanced strength and flexible.•A fully flexible lithium metal battery based on the MXene/Li anode shows long-term stability.