Effects of solid polymer electrolyte coating on the composition and morphology of the solid electrolyte interphase on Sn anodes

• Published in: Journal of solid state electrochemistry Vol. 21; no. 4; pp. 955 - 966
• Main Authors: Cao, Zhenzhen, Meng, Haowen, Dou, Peng, Wang, Chao, Zheng, Jiao, Xu, Xinhua
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-04-2017; Springer Nature B.V
• Subjects: Analytical Chemistry; Anode effect; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Coating effects; Composition; Condensed Matter Physics; Electrochemistry; Electrode materials; Electrodes; Electrolytes; Energy Storage; Flux density; Lithium; Lithium-ion batteries; Morphology; Nanoparticles; Original Paper; Photoelectrons; Physical Chemistry; Polyethylene oxide; Polymer coatings; Polymers; Rechargeable batteries; Solid electrolytes; Tin; X ray photoelectron spectroscopy; Lithium-ion batteries; Stable; Solid electrolyte interphase; Polymer coating; Tin anode
• ISSN: 1432-8488; 1433-0768
• DOI: 10.1007/s10008-016-3440-z

In order to discuss the effect of polymer coating layer on the Sn anode, the composition and morphology of the solid electrolyte interphase (SEI) film on the surface of Sn and Sn@PEO anode materials have been investigated. Compared with the bare cycled Sn electrode, the SEI on the surface of cycled Sn@PEO electrode is thinner, smoother, and more stable. Therefore, the Sn@PEO nanoparticles can basically keep the original appearance during cycling. Based on the results obtained from X-ray photoelectron spectroscopy (XPS), the SEI formed on the Sn@PEO electrode is characterized by inorganic components (Li
2
CO
3
)-rich outer layer and organic components-rich inner which could make the SEI more stable and inhibit the electrolyte immerging into the active materials. In particular, the elastic ion-conductive polyethylene oxide (PEO) coating could increase the toughness of SEI and allow the SEI to endure the stress variation in repetitive lithium insertion and extraction process. As a result, the Sn@PEO electrodes show significantly better capacity retention than bare Sn electrodes. The findings can serve as the theoretical foundation for the design of lithium-ion battery electrode with high energy density and long cycle life.