Silk fibroin-based biopolymer composite binders with gradient binding energy and strong adhesion force for high-performance micro-sized silicon anodes

作     者：Panpan Dong Xiahui Zhang Julio Zamora John McCloy Min-Kyu Song Panpan Dong;Xiahui Zhang;Julio Zamora;John McCloy;Min-Kyu Song

作者机构：School of Mechanical and Materials EngineeringWashington State UniversityPullmanWashington 99164United States 

出 版 物：《Journal of Energy Chemistry》 (能源化学（英文版）)

年 卷 期：2023年第80卷第5期

页      面：442-451,I0010页

核心收录：

学科分类：0710[理学-生物学] 081702[工学-化学工艺] 0808[工学-电气工程] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 0817[工学-化学工程与技术] 0703[理学-化学] 

基　　金：financially supported by Ecellix Inc。 

主　　题：Micro-sized silicon Binder Silk fbroin Strong adhesion force Rate capability Cyclability 

摘      要：Micro-sized silicon anodes have shown much promise in large-scale industrial production of high-energy lithium batteries.However,large volume change(300%)of silicon anodes causes severe particle pulverization and the formation of unstable solid electrolyte interphases during cycling,leading to rapid capacity decay and short cycle life of lithium-ion batteries.When addressing such issues,binder plays key roles in obtaining good structural integrity of silicon anodes.Herein,we report a biopolymer composite binder composed of rigid poly(acrylic acid)(PAA)and flexible silk fibroin(SF)tailored for micro-sized silicon anodes.The PAA/SF binder shows robust gradient binding energy via chemical interactions between carboxyl and amide groups,which can effectively accommodate large volume change of silicon.This PAA/SF binder also shows much stronger adhesion force and improved binding towards high-surface/defective carbon additives,resulting in better electrochemical stability and higher coulombic efficiency,than conventional PAA binder.As such,micro-sized silicon/carbon anodes fabricated with novel PAA/SF binder exhibit much better cyclability(up to 500 cycles at 0.5 C)and enhanced rate capability compared with conventional PAA-based anodes.This work provides new insights into the design of functional binders for high-capacity electrodes suffering from large volume change for the development of nextgeneration lithium batteries.