Effect of Silyl Ether‐functinoalized Dimethoxydimethylsilane on Electrochemical Performance of a Ni‐rich NCM Cathode

Abstract Dimethoxydimethylsilane (DODSi) is used as an interface stabilizing additive through a selective HF scavenging reaction for layered Ni‐rich oxide cathodes. Ex situ NMR analyses demonstrated that DODSi effectively removes HF from the electrolyte based on the matched chemical reactivity of Si with F − and O with H + . The cells employing DODSi exhibit higher specific capacity with retention than those cycled with a DODSi‐free electrolyte even under in situ HF generating conditions. Scanning electron microscopy (SEM), X‐ray photoelectron spectroscopy (XPS), and inductively coupled plasma‐mass spectroscopy (ICP‐MS) analyses indicate that DODSi effectively protects the Ni‐rich oxide cathodes against HF corrosion, resulting in improved surface stability of Ni‐rich cathodes.