Here, we show how EEI layer depends on different positive electrodes (LiCoO2 and NMC electrodes with different Ni content) and different electrolyte additives (diphenyl carbonate and adiponitrile) by using X-ray Photoelectron Spectroscopy (XPS). We also highlight the importance of using carbon-free, binder-free electrodes to unambiguously pinpoint the reactivity of the electrolyte at the positive electrode . The analysis of the XPS results points to a strong dependency of the surface reactivity on different electrode and electrolyte composition.
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