Zhang Jingjing, Su Zhengkang, Jin Junhong, Yang Shenglin, Yu Aishui, Li Guang
State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, China.
Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Institute of New Energy, Collaborative Innovation Center of Chemistry for Energy Materials, Laboratory of Advanced Materials, Fudan University, Shanghai 200438, China.
ACS Appl Mater Interfaces. 2021 Aug 25;13(33):39311-39321. doi: 10.1021/acsami.1c09319. Epub 2021 Aug 9.
Lithium dendrite formation has hindered the practical implementation of lithium metal batteries with higher energy densities compared with those of conventional lithium-ion batteries. Herein, a nanoconfinement strategy to access dendrite-free lithium metal anodes comprising three-dimensional (3D) hollow porous multi-nanochannel carbon fiber embedded with TiO nanocrystals (HTCNF) is reported. The transport of the lithium ions is facilitated by the 3D architecture. Functioning as nanoseeds, the TiO nanocrystals guide the lithium ions toward forming uniform deposits, which are further confined inside the hollow carbon fibers and the 3D HTCNF layer. Site-selective deposition coupled with the nanoconfinement of lithium metal modifies the Li plating/stripping behavior and effectively suppresses the dendrite growth. The HTCNF-Li cell delivers a stable cycling performance of 1300 h with a voltage hysteresis as low as 6 mV. The assembled HTCNF-Li//LiFePO full cell displays a compelling rate performance and enhanced cycling stability with high capacity retention (90% after 400 cycles at 0.5 C). Our results demonstrate a new and potentially scalable route to resolve the lithium dendrite growth issue for enhanced electrochemical performances, which can be further extended to other metal battery systems.
与传统锂离子电池相比，锂枝晶的形成阻碍了具有更高能量密度的锂金属电池的实际应用。在此，报道了一种制备无枝晶锂金属负极的纳米限域策略，该负极由嵌入TiO纳米晶体的三维（3D）中空多孔多纳米通道碳纤维（HTCNF）组成。3D结构促进了锂离子的传输。TiO纳米晶体作为纳米晶种，引导锂离子形成均匀的沉积物，这些沉积物进一步被限制在中空碳纤维和3D HTCNF层内。锂金属的位点选择性沉积与纳米限域相结合，改变了锂的电镀/剥离行为，有效抑制了枝晶生长。HTCNF-Li电池具有1300小时的稳定循环性能，电压滞后低至6 mV。组装的HTCNF-Li//LiFePO全电池表现出令人信服的倍率性能和增强的循环稳定性，具有高容量保持率（在0.5 C下400次循环后为90%）。我们的结果展示了一条新的、具有潜在可扩展性的途径，以解决锂枝晶生长问题，从而提高电化学性能，这可以进一步扩展到其他金属电池系统。
