Abstract
AbstractTo improve the cycle life of sodium‐ion batteries, it is essential to understand the microscopic processes that lead to cell degradation. The mismatched response time of anode and cathode has profound but poorly understood impact on cycle life. In this work, we combine electrochemical and materials characterization along with electrochemical modeling to investigate the root cause of degradation in sodium‐ion full cells made from Na4Fe3(PO4)2P2O7 (NFPP) cathodes and hard carbon (HC) anode. Our results pinpoint to the slow diffusion of Na in HC as the main cause of diffusional polarization that leads to cathode experiencing high local potentials and ultimately to active material loss over cycling. We demonstrate that by reducing the anode particle size, the diffusional timescales in anode can be matched with that of cathode to improve both extractable capacity as well as cycle life. These observations shed light on non‐intuitive and intricate ways in which cathode and anode can interact with each other to cause degradation in Na‐ion batteries and how microscopic understanding of these cause and effects can help design long lasting batteries.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: 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.