Abstract
AbstractRechargeable graphite dual‐ion batteries are extremely appealing for grid‐level stationary storage of electricity, thanks to the low‐cost and high‐performance metrics, such as high‐power density, energy efficiency, long cycling life, and good energy density. An in‐depth understanding of the anion intercalation mechanism in graphite is fundamental for the design of highly efficient systems. In this work, a comparison is presented between pyrolytic (PG) and natural (NG) graphite as positive electrode materials in rechargeable aluminum batteries, employing an ionic liquid electrolyte. The two systems are characterized by operando synchrotron energy‐dispersive X‐ray diffraction and time‐resolved computed tomography simultaneously, establishing a powerful characterization methodology, which can also be applied more in general to carbon‐based energy‐related materials. A more in‐depth insight into the AlCl4−/graphite intercalation mechanism is obtained, evidencing a mixed‐staged region in the initial phase and a two‐staged region in the second phase. Moreover, strain analysis suggests a correlation between the irreversibility of the PG electrode and the increase of the inhomogenous strain. Finally, the imaging analysis reveals the influence of graphite morphology in the electrode volume expansion upon cycling.
Highlights
Rechargeable graphite dual-ion batteries are extremely appealing for grid-level stationary storage of electricity, thanks to the low-cost and high-performanceAluminum batteries are considered sustainmetrics, such as high-power density, energy efficiency, long cycling life, and good energy density
We investigate in detail the intercalation mechanism of the AlCl4− anion in graphite by operando energy-dispersive X-ray diffraction (ED-XRD) combined with
Based on voltage profile behavior and ED-XRD pattern evolution, it is indicated that the initial phase is a mixed-staged region, followed by a process with the characteristics of a two-staged region
Summary
Rechargeable graphite dual-ion batteries are extremely appealing for grid-level stationary storage of electricity, thanks to the low-cost and high-performance. [+]Present address: Helmholtz Institute Ulm (HIU), Helmholtzstrasse 11, 89081 Ulm, Germany; Karlsruhe Institute of Technology (KIT), P.O. Box 3640, 76021 Karlsruhe, Germany bility have been reported employing graphite positive electrodes.[16,17,18] aluminum/graphite cells are characterized by a limited energy density, due to limited delivered capacity, relatively low voltage, and the electrolyte consumption during the cell operation.[19,20,21] the expected low cost of materials employed and the extremely high rate capability, being in the range of electrochemical supercapacitors make this system extremely appealing for grid-level stationary storage of electricity.[20,21] The reaction mechanism of the Al/graphite cell involves the anion (AlCl4−) intercalation between graphite layers.[22,23,24,25] The intercalation process follows a staging mechanism with the formation of graphite intercalated compounds (GICs).[26,27] The investigation and understanding of the reaction mechanisms can provide valuable information for the further development of the Al/graphite system. These data are fundamental for the design of materials and cell configurations for future large-scale application of this battery system
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
