A New Electrolyte Formulation for Securing High Temperature Cycling and Storage Performances of Na‐Ion Batteries. Issue 41 (20th September 2019)

• Record Type: Journal Article
• Authors: Yan, Guochun; Reeves, Kyle; Foix, Dominique; Li, Zhujie; Cometto, Claudio; Mariyappan, Sathiya; Salanne, Mathieu; Tarascon, Jean‐Marie
• Is Part Of: Advanced energy materials. Volume 9:Issue 41(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-09-20
• Subjects: electrolyte additives -- high temperature performance -- sodium ion batteries -- solid electrolyte interface; Energy harvesting -- Materials -- Periodicals; Energy conversion -- Materials -- Periodicals; Energy storage -- Materials -- Periodicals; Photovoltaics -- Periodicals; Fuel cells -- Periodicals; Thermoelectric materials -- Periodicals; 621.31
• DOI: 10.1002/aenm.201901431
• Languages: English
• ISSNs: 1614-6832

Abstract

Abstract: The Na‐ion battery is recognized as a possible alternative to the Li‐ion battery for applications where power and cost override energy density performance. However, the increasing instability of their electrolyte with temperature is still problematic. Thus, a central question remains how to design Na‐based electrolytes. Here, the discovery of a Na‐based electrolyte formulation is reported which enlists four additives (vinylene carbonate, succinonitrile, 1, 3‐propane sultone, and sodium difluoro(oxalate)borate) in proper quantities that synergistically combine their positive attributes to enable a stable solid electrolyte interphase at both negative and positive electrodes surface at 55 °C. Moreover, the role of each additive that consists in producing specific NaF coatings, thin elastomers, sulfate‐based deposits, and so on via combined impedance and X‐ray photoelectron spectroscopy is rationalized. It is demonstrated that empirical electrolyte design rules previously established for Li‐ion technology together with theoretical guidance is vital in the quest for better Na‐based electrolytes that can be extended to other chemistries. Overall, this finding, which is implemented to 18 650 cells, widens the route to the rapid development of the Na‐ion technology based on Na3 V2 (PO4 )2 F3 /C chemistry. Abstract : Electrolyte additives to achieve a thin, stable solid electrolyte interface (SEI) in sodium ion batteries are explored. The derived electrolyte using 1 m NaPF6 in EC‐PC with additives vinylene carbonate (VC), succinonitrile (SN), 1, 3‐propane sultone (PS), and sodium difluoro(oxalate)borate (NaODFB) leads to stable long cycling performance even at high temperature (55 °C) and reduced self‐discharge on long term storage at 100% state of charge (SOC).