1. Stable Li storage in micron-sized SiO particles with rigid-flexible coating
- Author
-
Liu Zhu, Lin-Bo Huang, Hongliang Li, Ming-Yan Yan, Quan Xu, Sen Xin, Yu-Guo Guo, Zhuo-Ya Lu, and Ke-Cheng Jiang
- Subjects
Materials science ,Energy Engineering and Power Technology ,02 engineering and technology ,Electrolyte ,engineering.material ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrochemistry ,01 natural sciences ,Silicon monoxide ,0104 chemical sciences ,Anode ,chemistry.chemical_compound ,Fuel Technology ,Coating ,chemistry ,Chemical engineering ,engineering ,Particle ,Graphite ,0210 nano-technology ,Layer (electronics) ,Energy (miscellaneous) - Abstract
Micrometre-sized electrode materials have distinct advantages for battery applications in terms of energy density, processability, safety and cost. For the silicon monoxide anode that undergoes electrochemical alloying reaction with Li, the Li (de)intercalation by micron-sized active particles usually accompanies with a large volume variation, which pulverizes the particle structure and leads to rapidly faded storage performance. In this work, we proposed to stabilize the electrochemistry vs. Li of the micron-SiOx anode by forming a rigid-flexible bi-layer coating on the particle surface. The coating consists of pyrolysis carbon as the inner layer and polydopamine as the outer layer. While the inner layer guarantees high structural rigidity at particle surface and provides efficient pathway for electron conduction, the outer layer shows high flexibility for maintaining the integrity of micrometre-sized particles against drastic volume variation, and together they facilitate formation of stable solid electrolyte interface on the SiOx particles. A composite anode prepared by mixing the coated micron-SiOx with graphite delivered improved Li storage performance, and promised a high-capacity, long-life LiFePO4/SiOx-graphite pouch cell. Our strategy provides a general and feasible solution for building high-energy rechargeable batteries from micrometre-sized electrode materials with significant volume variation.
- Published
- 2022