Scalable spray-coated graphene-based electrodes for high-power electrochemical double-layer capacitors operating over a wide range of temperature

Mohammad Akbari Garakani; Sebastiano Bellani; Vittorio Pellegrini; Reinier Oropesa-Nuñez; Antonio Esau Del RioCastillo; Sara Abouali; Leyla Najafi; Beatriz Martín-García; Alberto Ansaldo; Paolo Bondavalli; Cansunur Demirci; Valentino Romano; Elisa Mantero; Luigi Marasco; Mirko Prato; Gaetan Bracciale; Francesco Bonaccorso

doi:10.1016/j.ensm.2020.08.036

arXiv · 2010.07250

Scalable spray-coated graphene-based electrodes for high-power electrochemical double-layer capacitors operating over a wide range of temperature

Mohammad Akbari Garakani·Sebastiano Bellani·Vittorio Pellegrini·Reinier Oropesa-Nuñez·Antonio Esau Del RioCastillo·Sara Abouali·Leyla Najafi·Beatriz Martín-García·Alberto Ansaldo·Paolo Bondavalli·Cansunur Demirci·Valentino Romano·Elisa Mantero·Luigi Marasco·Mirko Prato·Gaetan Bracciale·Francesco Bonaccorso

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Abstract

Advancements in electrochemical double-layer capacitor (EDLC) technology require the concomitant use of novel efficient electrode materials and viable electrode manufacturing methods. Cost-effectiveness, scalability and sustainability are key-drivers for fulfilling product development chain accepted by worldwide legislations. Herein, we report a scalable and sprayable "green" electrode material-based ink based on activated carbon and single-/few-layer graphene (SLG/FLG) flakes. We show that, contrary to commercial reduced graphene oxide, defect-free and flat SLG/FLG flakes reduce the friction of ions over the electrode films, while spray coating deposition of our ink maximises the electrolyte accessibility to the electrode surface area. Sprayed SLG/FLG flakes-based EDLCs display superior rate capability performance (e.g., specific energies of 31.5, 23.7 and 12.5 Wh kg-1 at specific powers of 150, 7500 and 30000 W kg-1, respectively) compared to both SLG/FLG flakes-free devices and commercial-like EDLCs produced by slurry-coating method. The use of SLG/FLG flakes enables our sprayed EDLCs to operate in a wide range of temperature (-40/+100{\deg}C) compatible with ionic liquid/organic solvent-based electrolytes, overcoming the specific power limits of AC-based EDLCs. A prototype EDLCs stack consisting of multiple large-area EDLCs, each one displaying a capacitance of 25 F, demonstrates the industrial potential of our technology.

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Mohammad Akbari Garakani, Sebastiano Bellani, Vittorio Pellegrini, Reinier Oropesa-Nuñez, Antonio Esau Del RioCastillo, Sara Abouali, Leyla Najafi, Beatriz Martín-García, Alberto Ansaldo, Paolo Bondavalli, Cansunur Demirci, Valentino Romano, Elisa Mantero, Luigi Marasco, Mirko Prato, Gaetan Bracciale, Francesco Bonaccorso. 2020-10-14. Scalable spray-coated graphene-based electrodes for high-power electrochemical double-layer capacitors operating over a wide range of temperature. https://doi.org/10.1016/j.ensm.2020.08.036

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