Interface Engineering Enables Wide-Temperature Li-Ion Storage in Commercial Silicon-Based Anodes

• Published in: Small (Weinheim an der Bergstrasse, Germany) p. e2310633
• Main Authors: Zhang, Chenwu, Ji, Fengjun, Li, Deping, Bai, Tiansheng, Zhang, Hongqiang, Xia, Weihao, Shi, Xiuling, Li, Kaikai, Lu, Jingyu, Wang, Yu, Ci, Lijie
• Format: Journal Article
• Language: English
• Published: Germany 26.01.2024
• Subjects: lithium-ion batteries; silicon; wide-temperature applications; interface engineering
• ISSN: 1613-6810; 1613-6829
• DOI: 10.1002/smll.202310633

Silicon-based materials have been considered potential anode materials for next-generation lithium-ion batteries based on their high theoretical capacity and low working voltage. However, side reactions at the Si/electrolyte interface bring annoying issues like low Coulombic efficiency, sluggish ionic transport, and inferior temperature compatibility. In this work, the surface Al O coating layer is proposed as an artificial solid electrolyte interphase (SEI), which can serve as a physical barrier against the invasion of byproducts like HF(Hydrogen Fluoride) from the decomposition of electrolyte, and acts as a fast Li-ion transport pathway. Besides, the intrinsically high mechanical strength can effectively inhibit the volume expansion of the silicon particles, thus promoting the cyclability. The as-assembled battery cell with the Al O -coated Si-C anode exhibits a high initial Coulombic efficiency of 80% at RT and a capacity retention ratio up to ≈81.9% after 100 cycles, which is much higher than that of the pristine Si-C anode (≈74.8%). Besides, the expansion rate can also be decreased from 103% to 50%. Moreover, the Al O -coated Si-C anode also extends the working temperature from room temperature to 0 °C-60 °C. Overall, this work provides an efficient strategy for regulating the interface reactions of Si-based anode and pushes forward the practical applications at real conditions.