Zhou XiaoHui, Huang WuJun, Shi ChenGuang, Wang Kang, Zhang Rui, Guo JinCheng, Wen YanFen, Zhang ShaoJian, Wang Qiong, Huang Ling, Li JunTao, Zhou XiaoDong, Sun ShiGang
Institute for Materials Research and Innovation, Department of Chemical Engineering , University of Louisiana at Lafayette , Lafayette , Louisiana 70504 , United States.
ACS Appl Mater Interfaces. 2018 Oct 17;10(41):35296-35305. doi: 10.1021/acsami.8b13506. Epub 2018 Oct 5.
Suppressing the formation of lithium (Li) dendrites is central to implementing Li-metal anode, which has gained growing attention due to its ultrahigh specific capacity and low redox potential. Here, a novel approach is adopted to deposit Li-metal within a rigid three-dimensional (3D) carbon paper (3DCP) network, which consists of a cross-link framework of carbon fibers and graphene nanosheets (GNs). This unique structure yields a uniform distribution of Li-nuclei during the preliminary stage of Li-plating and the formation of a stable solid-electrolyte interface. The as-obtained anode can deliver a high areal capacity of 10 mAh cm without the dendritic formation after 1000 cycles in a Li@3DCP/LiFePO full cell at 4 C. In addition, the Li@3DCP anode displays low voltage platform (<20 mV at 1 mA cm), high plating/stripping efficiency (99.0%), and long lifespan (>1000 h). When coupled with LiNiCoAlO cathode, the Li@3DCP electrode exhibits a superior rate capability up to 10 C and high temperature performance (60 °C). The unprecedented performance is attributed to the desirable combination of micro/nanostructures in 3DCP, in which carbon fiber framework provides the mechanical stability for volume change, whereas numerous lithiophilicity sites on GNs enable the suppression of Li-dendrite growth.
抑制锂(Li)枝晶的形成是实现锂金属负极的关键,锂金属负极因其超高的比容量和低氧化还原电位而受到越来越多的关注。在此,采用了一种新颖的方法,将锂金属沉积在由碳纤维和石墨烯纳米片(GNs)的交联框架组成的刚性三维(3D)碳纸(3DCP)网络中。这种独特的结构在锂电镀的初始阶段产生锂核的均匀分布,并形成稳定的固体电解质界面。所制备的负极在4C下的Li@3DCP/LiFePO全电池中经过1000次循环后,可提供10 mAh cm的高面积容量且无枝晶形成。此外,Li@3DCP负极显示出低电压平台(在1 mA cm时<20 mV)、高电镀/剥离效率(99.0%)和长寿命(>1000 h)。当与LiNiCoAlO正极耦合时,Li@3DCP电极表现出高达10C的优异倍率性能和高温性能(60°C)。这种前所未有的性能归因于3DCP中微/纳米结构的理想组合,其中碳纤维框架为体积变化提供机械稳定性,而GNs上大量的亲锂位点能够抑制锂枝晶的生长。