Abstract
Il progetto si propone i seguenti obiettivi principali: 1) studio computazionale di diversi leganti self-healing al fine di ottenere una comprensione approfondita dei meccanismi strutturali e chimici coinvolti nel processo di self-healing; 2) confronto teorico ed sperimentale delle proprietà rilevanti di diversi leganti; 3) identificazione di modifiche ai leganti che potrebbero portare a una migliore performance; 4) test e caratterizzazione degli elettrodi e delle celle risultanti; 5) test della capacità predittiva delle simulazioni. Lo schema computazionale si basa su un nuovo protocollo multiscala che include studi di simulazioni di carica e scarica dell'anodo con leganti concettualmente diversi utilizzando dinamica molecolare classica e campi di forza Reax-FF, seguiti da una raffinazione DFT delle strutture a più bassa energia. Le proprietà calcolate (stabilità, adesione alle superfici dell'anodo, diffusione ionica, proprietà reologiche) saranno confrontate con i risultati sperimentali dell'analisi fisico-chimica (test di adesione e coesione, test reologici, microscopia elettronica a scansione, spettroscopie di diversi tipi, analisi termogravimetrica e calorimetrica differenziale, ecc.) e la caratterizzazione elettrochimica (voltammetria ciclica, cicli di carica/scarica galvanostatici, spettroscopia di impedenza) del legante e dell'elettrodo.
Results achieved
Atomistic simulations of the electrode-binder interfaces provided information into interfacial phenomena, supporting experimental activities. Chitosan was selected as binder, and from a scientific and technical perspective, notable results were achieved in binder optimization and characterization. These efforts contributed to improving material performance and understanding the mechanisms of electrode behavior. Stable electrodes with high specific capacity have been prepared and tested over several hundreds of cycles. Adhesion calculations have been carried out and demonstrated that chitosan adhesion to graphene, due to long range electrostatic forces, shows a large flexibility with functionalization, which makes it a material with great potential as a binder, and the preliminary simulations on Li ion behavior (diffusion and transport) in self-healing polymers showed a correlation between the Li ion self-diffusion coefficient and the amount of self-healing functionalities in a binder mixture. So, the outcome of the project is the development and optimisation of sustainable, water-processable binders based on chitosan–lactic acid systems. The results confirmed that chitosan dissolved in 2–5 wt % lactic acid provides homogeneous, mechanically robust graphite coatings, which exhibited a stable cycling behaviour (~330 mAh g⁻¹, coulombic efficiency > 99 %). These findings complement structural studies and simulations, ensuring full cross-validation of the binder’s performance. The BIONIC project fostered strong scientific collaboration among the participating universities combining experimental with modeling activities. Thanks to the continuous and systematic exchange of information among partners, the experimental results obtained at the different universities could be effectively correlated and used to support the development, optimisation, and validation of the modelling activities. The work carried out in BIONIC Project clearly demonstrates that the chitosan–lactic acid binder ensures high mechanical and electrochemical stability and can serve as a sustainable alternative to PVDF-based systems, in line with Battery2030+, REPowerEU and PNRR objectives.Project details
Unibo Team Leader: Catia Arbizzani
Unibo involved Department/s:
Dipartimento di Chimica "Giacomo Ciamician"
Coordinator:
Università degli studi di Modena e Reggio Emilia - UNIMORE(Italy)
Total Unibo Contribution: Euro (EUR) 63.586,00
Project Duration in months: 24
Start Date:
16/10/2023
End Date:
15/10/2025
