An all-electrochem-active silicon anode enabled by spontaneous Li–Si alloying for ultra-high performance solid-state batteries

Zhiyong Zhang; Zhefei Sun; Xiang Han; Yan Liu; Shanpeng Pei; Yahui Li; Linshan Luo; Pengfei Su; Chaofei Lan; Ziqi Zhang; Shaowen Xu; Shengshi Guo; Wei Huang; Songyan Chen; Ming-Sheng Wang

doi:10.1039/D3EE03877G

An all-electrochem-active silicon anode enabled by spontaneous Li–Si alloying for ultra-high performance solid-state batteries†

Zhiyong Zhang,^a Zhefei Sun,^b Xiang Han,

^c Yan Liu,^d Shanpeng Pei,^ae Yahui Li,^a Linshan Luo,^a Pengfei Su,^a Chaofei Lan,^a Ziqi Zhang,^f Shaowen Xu,

^a Shengshi Guo,^a Wei Huang,*^a Songyan Chen

*^a and Ming-Sheng Wang

*^b

Author affiliations

* Corresponding authors

^a Department of Physics, Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices, Key Laboratory of Low Dimensional Condensed Matter Physics (Department of Education of Fujian Province), Jiujiang Research Institute, Xiamen University, Xiamen 361005, China
E-mail: sychen@xmu.edu.cn, weihuang@xmu.edu.cn

^b State Key Lab of Physical Chemistry of Solid Surfaces, College of Materials, Xiamen University, Xiamen 361005, China
E-mail: mswang@xmu.edu.cn

^c College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China

^d School of Semiconductor Science and Technology South China Normal University, Foshan 528225, China

^e Shandong Electric Power Engineering Consulting Institute Corporation, Jinan 250031, China

^f Science and Technology on Analog Integrated Circuit Laboratory, Chongqing 400000, China

Abstract

Li–Si alloys are considered as key anode materials for advanced silicon-based solid-state batteries (Si-ASSBs) due to their high ionic/electronic conductivity. However, the high content of Li in Li–Si alloys increases the risk of Li dendrite growth and soft short circuits during battery charging. Herein, an all-electrochem-active Si/Li₂₁Si₅ composite anode is developed with the rational architecture and optimized ratio of Li₂₁Si₅ and pure Si. By utilizing defects in the oxide layer of micron Si, the Li₂₁Si₅ alloy is first synthesized separately by a quick and spontaneous Li–Si alloying reaction, followed by its mixing with Si particles by cold-pressing. In this composite anode, the Li₂₁Si₅ grains are uniformly distributed among the Si particles, and serve as a soft buffer for Si. Due to the limited self-discharge between Li₂₁Si₅ grains and Si particles, the Li₂₁Si₅ alloy maintains a lithium-saturated state and functions as a lithium supplement. Meanwhile, it constructs a conductive network in the anode, which can facilitate the transport of lithium ions and induce their storage in Si particles, thus avoiding dendrite formation. Consequently, the Si/Li₂₁Si₅-ASSB can achieve an ultra-high initial Coulombic efficiency (ICE) of 97.8% at 25 °C, as well as a low expansion rate of 18.9% at a surprisingly large areal capacity of 17.9 mA h cm⁻². This work provides a new method and valuable insight into Li–Si alloy synthesis, and the obtained Si-based anode shows great promise for application in ASSBs.

This article is part of the themed collection: Energy & Environmental Science Recent HOT Articles

Energy & Environmental Science

An all-electrochem-active silicon anode enabled by spontaneous Li–Si alloying for ultra-high performance solid-state batteries†

Abstract

Supplementary files

Article information

Download Citation

Permissions

An all-electrochem-active silicon anode enabled by spontaneous Li–Si alloying for ultra-high performance solid-state batteries

Social activity

Search articles by author

Spotlight

Advertisements