3D printed separator for the thermal management of high-performance Li metal anodes

作者：Liu, Yang; Qiao, Yun; Zhang, Ying; Yang, Zhi; Gao, Tingting; Kirsch, Dylan; Liu, Boyang; Song, Jianwei; Yang, Bao; Hu, Liangbing^*

来源：Energy Storage Materials, 2018, 12: 197-203.

DOI：10.1016/j.ensm.2017.12.019

• 3D Printing
• Thermal management separator
• Boron nitride
• Lithium metal anode

Lithium (Li) metal anodes with a high theoretical gravimetric capacity and a low redox potential have attracted considerable attention for Li-ion based batteries, including Li-sulfur (Li-S) and Li-oxygen (Li-O-2) batteries. The elimination of safety concerns and long cycling stability issues are the main challenges that must be solved to apply Li metal anodes in any application. Herein, we design a novel and safe separator for Li metal batteries by integrating thermally management boron nitride (BN) nanosheets into poly vinylidene fluoride-hexafluoropropene (PVDF-HFP) via an advanced extrusion based 3D printing technique. The BN-separator offers a uniform thermal distribution interface, which enables homogeneous Li nucleation, enhanced suppression of Li dendrite growth, and further improves the overall electrochemical performance. A stable Coulombic efficiency of 92% is maintained after 90 cycles at 1 mA cm(-2) by using this novel separator in Li/Cu cells. In contrast, the Coulombic efficiency of the control cells decreases to 70% after 30 cycles at a current density of 1 mA cm(-2). In addition, in a Li/Li symmetric configuration, the cells using the 3D printed BN-separator exhibit improved cycling stability with lower voltage polarization over 500 h. Our findings on 3D printing for a thermally managing BN-separator can serve as a general strategy for further advanced rechargeable batteries.

• 出版日期2018-5
• 单位河南师范大学