Premium
Strategies for Mitigating Dissolution of Solid Electrolyte Interphases in Sodium‐Ion Batteries
Author(s) -
Ma Le Anh,
Naylor Andrew J.,
Nyholm Leif,
Younesi Reza
Publication year - 2021
Publication title -
angewandte chemie international edition
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.831
H-Index - 550
eISSN - 1521-3773
pISSN - 1433-7851
DOI - 10.1002/anie.202013803
Subject(s) - dissolution , electrolyte , solubility , electrochemistry , sodium , separator (oil production) , chemistry , inorganic chemistry , chemical engineering , interphase , electrode , organic chemistry , physics , genetics , biology , engineering , thermodynamics
Abstract The interfacial reactions in sodium‐ion batteries (SIBs) are not well understood yet. The formation of a stable solid electrolyte interphase (SEI) in SIBs is still challenging due to the higher solubility of the SEI components compared to lithium analogues. This study therefore aims to shed light on the dissolution of SEI influenced by the electrolyte chemistry. By conducting electrochemical tests with extended open circuit pauses, and using surface spectroscopy, we determine the extent of self‐discharge due to SEI dissolution. Instead of using a conventional separator, β‐alumina was used as sodium‐conductive membrane to avoid crosstalk between the working and sodium‐metal counter electrode. The relative capacity loss after a pause of 50 hours in the tested electrolyte systems ranges up to 30 %. The solubility of typical inorganic SEI species like NaF and Na 2 CO 3 was determined. The electrolytes were then saturated by those SEI species in order to oppose ageing due to the dissolution of the SEI.