Lithium manganese oxide spinels are promising candidate materials for thin-film lithium-ion batteries owing to their high voltage, high specific capacity for storage of electrochemical energy, and minimal structural changes during battery operation. Atomic layer deposition (ALD) offers many benefits for preparing all-solidstate thin-film batteries, including excellent conformity and thickness control of the films. Yet, the number of available lithium-containing electrode materials obtained by ALD is limited. In this article, we demonstrate the ALD of lithium manganese oxide, Li x Mn 2 O 4 , from Mn(thd) 3 , Li(thd), and ozone. Films were polycrystalline in their asdeposited state and contained less than 0.5 at. % impurities. The chemical reactions between the lithium precursor and the film were found not to be purely surface-limited but to include a bulk component as well, contrary to what is usually found for ALD processes. In addition, we show a process for using Li(thd)/ozone and LiO t Bu/water treatments to transform ALD-MnO 2 and ALD-V 2 O 5 into Li x Mn 2 O 4 and Li x V 2 O 5 , respectively. The formed Li x Mn 2 O 4 films were characterized electrochemically and found to show high electrochemical capacities and high cycling stabilities.

The ferroelectric and electro-optical properties of LiNbO 3 make it an important material for current and future applications. It has also been suggested as a possible lead-free replacement for present PZTdevices. The atomic layer deposition (ALD) technique offers controlled deposition of films at an industrial scale and thus becomes an interesting tool for growth of LiNbO 3. We here report on ALD deposition of LiNbO 3 using lithium silylamide and niobium ethoxide as precursors, thereby providing good control of cation stoichiometry and films with low impurity levels of silicon. The deposited films are shown to be ferroelectric and their crystalline orientations can be guided by the choice of substrate. The films are polycrystalline on Si (100) as well as epitaxially oriented on substrates of Al 2 O 3 (012), Al 2 O 3 (001), and LaAlO 3 (012). The coercive field of samples deposited on Si (100) was found to be $220 kV cm À1 , with a remanent polarization of $0.4 mC cm À2. Deposition of lithium containing materials is traditionally challenging by ALD, and critical issues with such deposition are discussed.

The lithium ion battery concept is a promising energy storage system, both for larger automotive systems and smaller mobile devices. The smallest of these, the microbatteries, are commonly based on the all‐solid state concept consisting of thin layers of electroactive materials separated by a solid state electrolyte. The fact that solid state electrolytes are required puts rather severe constraints on the materials in terms of electronic and ionic conductivity, as well as lack of pinholes otherwise leading to self‐discharge. The atomic layer deposition (ALD) technology is especially suitable for realization of such microbatteries for the Li‐ion technology. ALD has an inherent nature to deposit conformal and pinhole free layers on complex geometrical shapes, an architecture most commonly adopted for microbattery designs. The current paper gives an overview of ALD‐type deposition processes of functional battery materials, including cathodes, electrolytes, and anodes with the aim of developing all‐solid‐state batteries. Deposition of Li‐containing materials by the ALD technique appears challenging and the status of current efforts is discussed.

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Atomic layer deposition (ALD) has been used to prepare nano-structured cathode films for Li-ion batteries of V2O5 from VO(thd)2 and ozone at 215 °C.