Coralloid Carbon Fiber-Based Composite Lithium Anode for Robust Lithium Metal Batteries

• Published in: Joule Vol. 2; no. 4; pp. 764 - 777
• Main Authors: Zhang, Rui, Chen, Xiang, Shen, Xin, Zhang, Xue-Qiang, Chen, Xiao-Ru, Cheng, Xin-Bing, Yan, Chong, Zhao, Chen-Zi, Zhang, Qiang
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 18.04.2018
• Subjects: carbon fiber; LiFePO4 cathode; lithiophilic surface; lithium dendrites; lithium metal anode; lithium metal batteries; lithium-ion batteries; lithium-sulfur batteries; molten lithium infusing; silver coating layer; carbon fiber; LiFePO4 cathode; lithium-ion batteries; lithiophilic surface; lithium metal batteries; lithium dendrites; silver coating layer; lithium metal anode; lithium-sulfur batteries; molten lithium infusing
• ISSN: 2542-4351; 2542-4351
• DOI: 10.1016/j.joule.2018.02.001

Lithium metal is among the most promising anode materials in next-generation energy-storage systems. However, Li dendrite growth and unstable solid electrolyte interphase have hindered its practical applications. Structured current collectors have been widely proposed to settle these issues, whereas the pre-filling of Li metal into structured anode is challenging. We proposed a coralloid silver-coated carbon fiber-based composite Li anode (CF/Ag-Li) through Ag electroplating and molten Li infusion. The molten Li can be infused into the carbon fiber framework due to the lithiophilic nature of Ag. In addition, a dendrite-free morphology and extraordinary electrochemical performance are achieved in Li-LiFePO4 and Li-sulfur cells. The CF/Ag-Li|Li symmetrical cells can cycle for 160 cycles at 10.0 mA cm−2 and 10.0 mAh cm−2. The CF/Ag-Li|S cells exhibited a high initial discharge capacity of 785 mAh g−1 and a large capacity retention rate after 400 cycles at 0.5C. [Display omitted] •Coralloid carbon fibers were achieved by electroplating Ag onto their surface•Ag coating layer endows electrodes with lithiophilic nature to syphon molten Li•The composite Li electrode can cycle without dendrite growth or volume change•The composite Li can match Li-containing (LiFePO4) and Li-free (sulfur) cathodes With the rapid development of electric vehicles and portable electronics such as mobile phones and laptops, the widely used lithium (Li)-ion batteries are having many difficulties in meeting the growing demands for high-energy-density energy-storage systems. Li metal, with an ultrahigh theoretical specific capacity of 3,860 mAh g−1 and the lowest negative electrochemical potential (−3.040 V versus standard hydrogen electrode), has become one of the most promising anode materials for next-generation batteries. Unfortunately, the practical application of Li metal anode has been hindered by its low cycling efficiency, short lifespan, and potential safety hazards. Herein we propose a Li-containing composite electrode based on coralloid carbon fibers that exhibited extraordinary electrochemical performance in full cells of Li-S and Li-LiFePO4 batteries. Such proof of concept on Li-infused structured electrodes sheds fresh light on the dendrite-free plating of Li metal anodes in working rechargeable batteries. Lithium (Li) metal is among the most promising anode materials for next-generation high-energy-density batteries. However, both dendrite growth and unstable solid electrolyte interphases have hindered its practical applications. Herein, we propose a coralloid carbon fiber-based composite lithium anode, which is an initially Li-containing structured anode. Such electrode design renders dendrite-free morphology during repeated stripping/plating cycles and extraordinary electrochemical performance in Li-LiFePO4 and Li-sulfur cells.