Liquid Metal-Modified Nanoporous SiGe Alloy as an Anode for Li-Ion Batteries and Its Self-Healing Performance
Fanran Meng, Fuqiang Wang, Haohui Yu, Zijun Zhao, Yang Lv, Chao Ma, Dong Zhang, Xizheng Liu
Abstract
Alloy-type anodes have drawn considerable attention because of their potential applications in Li-ion batteries with high energy density. However, their applications are still challenged by the dramatic volume change and side reactions at the fresh surface of alloy anodes. Herein, we proposed a liquid metal (LM)-modified nanoporous SiGe (NP-SiGe) alloy that could accommodate electrode expansion and repair the electrode surface. The difference between the equilibrium lithiation/delithiation potentials of Si and Ge could also mitigate the instantaneous mechanical stress. Morphological and structural characterization demonstrated that nanocylated LM particles were successfully embedded within the pore structure of NP-SiGe. The composite anode exhibits a highly reversible Li storage performance at room temperature and −20 °C. In addition, it delivers a capacity of ∼1200 mA h g–1 after 300 cycles at room temperature, while it retains ∼746.7 mA h g–1 after 100 cycles at −20 °C. The morphology of the cycled electrodes clearly demonstrates the self-healing performance of the LM components. This study provides new perspectives on high-performance alloy-type anodes, especially for all-climate applications.