Nanochitin as Binder in Li-Ion Battery Anodes Enabling Aqueous Processing and Superior Solid Electrolyte InterphaseShow others and affiliations
2026 (English)In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 18, no 16, p. 23181-23192Article in journal (Refereed) Published
Abstract [en]
Binders are essential components in battery systems that maintain the electrode structure and integrity throughout cycling. The choice of binder affects processing, electrochemical behavior, and end-of-life recovery. The widely used poly(vinylidene difluoride) (PVDF) binder is increasingly scrutinized since it is a polyfluoroalkyl compound and requires processing in organic solvents like N-methyl-2-pyrrolidone. Consequently, efforts are underway to identify more sustainable options. In this work, we present chitin nanofibers (ChNFs), derived from fisheries waste, as a biobased, fluorine-free alternative that enables fully aqueous electrode fabrication. ChNFs disperse more than 90% of graphite in water without the need for auxiliary agents such as surfactants. Colloidal probe microscopy shows that adhesion between protonated ChNFs and graphite depends on pH, likely being governed by cation−π interactions. This strong affinity facilitates the remarkable dispersing capability of ChNFs through a multifaceted mechanism. Adsorbed nanofibers confer electro-steric stabilization by extension into the aqueous phase. The strong ChNF network can physically entrap larger particles, greatly enhancing the long-term stability of ChNF–graphite suspensions. The ChNF–graphite dispersion exhibits rheological behavior suited for forming uniform electrode coatings. Electrodes prepared with 4% ChNFs deliver specific capacities of 370 mA h g–1 and enhanced capacity retention over 100 cycles compared to PVDF-based counterparts. Electron microscopy, X-ray photoelectron spectroscopy, and online electrochemical mass spectrometry analyses reveal that the nature of the binder dictates the solid electrolyte interphase (SEI) characteristics. The ChNF produces a more robust and stable SEI that suppresses electrolyte reduction, directly contributing to the enhanced electrochemical performance.
Place, publisher, year, edition, pages
American Chemical Society (ACS) , 2026. Vol. 18, no 16, p. 23181-23192
Keywords [en]
aqueous processing, binders, chitin nanofibers, gas evolution, graphite, lithium-ion battery
National Category
Materials Chemistry Other Chemistry Topics
Identifiers
URN: urn:nbn:se:kth:diva-381628DOI: 10.1021/acsami.6c01089ISI: 001743660600001PubMedID: 41999304Scopus ID: 2-s2.0-105037150897OAI: oai:DiVA.org:kth-381628DiVA, id: diva2:2061426
Note
QC 20260521
2026-05-212026-05-212026-05-21Bibliographically approved