Acta Phys. -Chim. Sin. ›› 2021, Vol. 37 ›› Issue (2): 2008088.doi: 10.3866/PKU.WHXB202008088

Special Issue: Lithium Metal Anodes

• ARTICLE • Previous Articles     Next Articles

Bacterial Cellulose-Derived Three-Dimensional Carbon Current Collectors for Dendrite-Free Lithium Metal Anodes

Yunbo Zhang1, Qiaowei Lin2, Junwei Han2, Zhiyuan Han2, Tong Li2, Feiyu Kang1,2, Quan-Hong Yang3, Wei Lü2,*()   

  1. 1 Tsinghua-Berkeley Shenzhen Institute (TBSI), Tsinghua University, Shenzhen 518055, Guangdong Province, China
    2 Shenzhen Geim Graphene Center, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, Guangdong Province, China
    3 State Key Laboratory of Chemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
  • Received:2020-08-31 Accepted:2020-09-30 Published:2020-10-19
  • Contact: Wei Lü E-mail:lv.wei@sz.tsinghua.edu.cn
  • About author:Wei Lü, Email: lv.wei@sz.tsinghua.edu.cn; Tel.: +86-755-86964142
  • Supported by:
    the National Key Research and Development Program of China(2018YFE0124500);the National Natural Science Foundation of China(51972190);the Guangdong Natural Science Funds for Distinguished Young Scholars(2017B030306006);Shenzhen Basic Research Project(JCYJ20180508152037520)

Abstract:

Lithium (Li) metal anodes are critical components for next-generation high-energy density batteries, owing to their high theoretical specific capacity (3800 mAh·g-1) and low voltage (-3.040 V versus the standard hydrogen electrode). However, their applications are hindered by dendrite growth, which potentially induces inner short circuit and leads to safety issues. Employing three-dimensional (3D) current collectors is an effective strategy to suppress dendrite growth by decreasing the local current density. However, many of the reported 3D current collectors have a lithiophobic surface, which leads to non-uniform Li+ ion deposition. Thus, a complicated modification process is required to increase the lithiophilic property of the current collectors. In addition, they have a large weight or volume, which greatly lowers the energy density of the entire anode. In this work, we report a lightweight 3D carbon current collector with a lithiophilic surface by employing the direct carbonization of low-cost bacterial cellulose (BC) biomass. The current collector is composed of electrically conductive, robust, and interconnected carbon nanofiber networks, which provide sufficient void space to accommodate a large amount of Li and buffer the volume changes during Li plating and stripping. More importantly, homogeneously distributed oxygen-containing functional groups on the nanofiber surface are retained by controlling the carbonization temperature. These functional groups serve as uniform nucleation sites and help realize uniform and dendrite-free Li deposition. Notably, the areal mass density of the 3D carbon current collector was only 0.32 mg·cm-2 and its mass ratio in the whole anode was 28.8%, with a capacity of 3 mAh·cm-2. This 3D carbon current collector facilitates the stable working of the half cells for 150 cycles under a high current density of 3 mA·cm-2 or a high capacity of 4 mAh·cm-2. Symmetric cells exhibit a steady cycling life as long as 600 h under a current density of 1 mA·cm-2 and a capacity of 1 mAh·cm-2. Moreover, appreciable cycling performance was realized in the full cells when the anodes were paired with LiNi0.8Co0.15Al0.05 cathodes. Furthermore, the low-cost raw materials and the simple preparation method promise significant potential for the future applications of the proposed 3D current collectors.

Key words: Lithium metal anode, Bacterial cellulose, Three-dimensional current collector, Lithium dendrite, Oxygen-containing functional group

MSC2000: 

  • O646