Integrated manufacturing of REciclable multi-material COmposites for the TRANSport sector
Designing Cellulose Triacetate?Based Universal Binder for High?Voltage Sodium?Ion Battery Cathodes with Enhanced Ionic Conductivity and Binding Strength
Cellulose triacetate?based binder with broad compatibility, high ionic conductivity, and superior binding strength has been successfully designed and validated through its application in high?voltage polyanionic cathodes (Na3V2(PO4)2O2F), layered oxide cathodes (NaNi1/3Fe1/3Mn1/3O2), and tunnel?type oxide cathodes (Na0.61[Mn0.27Fe0.34Ti0.39]O2). This work presents a sustainable and effective strategy for achieving high?performance sodium?ion batteries.Binders play a pivotal role in the performance of sodium?ion battery (SIB) cathodes, but traditional binders often struggle to balance broad compatibility, high ionic conductivity, superior binding strength, and environmental sustainability. In this study, a universal cellulose triacetate (TAC)?based binder (TAC?MMT) composed of TAC and natural montmorillonite (MMT) is designed to facilitate rapid Na+ transport pathways and establish a robust hydrogen?bonding network. This innovative TAC?MMT binder features a unique chemical structure that achieves high ionic conductivity through a self?enrichment and fast?transport mechanism, while its superior binding strength is attributed to hydrogen?bonding crosslinks between proton acceptors (C?O) in TAC and proton donors (?OH) in MMT. More importantly, the outstanding solubility and film?forming properties of TAC?MMT contribute to stable electrode protection and broad compatibility with high?voltage SIB cathodes. Benefiting from these advantages, the Na3V2(PO4)2O2F (NVPOF) electrodes with the TAC?MMT binder demonstrate exceptional performance, including a high capacity retention of 95.2% over 500 cycles at 5C and a rapid rate response of up to 15C. The versatility of the TAC?MMT binder is further confirmed with high?voltage NaNi1/3Fe1/3Mn1/3O2 and Na0.61[Mn0.27Fe0.34Ti0.39]O2 cathodes. This study highlights the potential of biomass?based binders as a sustainable and effective solution for advancing high?performance sodium?ion batteries.
» Publication Date: 03/04/2025
This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement Nº 768737
