A Critical Review: The Impact of the Battery Electrode Material Substrate on the Composition and Properties of Atomic Layer Deposition (ALD) Coatings

The applications of atomic layer deposition (ALD) technology in the Li-ion field are numerous: from protective coatings to high-surface area active materials and composite electrodes to manufacturing and production of battery materials. The synergy between electrode materials and ALD coatings has been proven repeatedly; however, extensive knowledge of the reasons behind these benefits is needed. The lack of such know-how is partly due to the common deposition and characterization methods applied in the field, where the deposition of films is performed on so-called “simple substrates” (such as copper, silicon, or stainless steel) as opposed to the intended substrate material, which is either a complicated matrix of metal oxides or porous/inactive surfaces. In fact, real interactions between the electrode materials and the ALD coating vary greatly and depend on the substrate material identity. Here, the authors provide the reader with insight and an eye-opening review of the effect of battery electrode substrates on the composition and quality of ALD coatings. They also report the importance of the suitable and most applicable characterization methods for ALD coatings and ALD film-electrode interfaces.