Suppression of formation of lithium dendrite via surface modification by 2-D lithium phosphorous oxynitride as a highly stable anode for metal lithium batteries

Lithium phosphorous oxynitride (LiPON) is a thin film solid electrolyte with an amorphous structure and is the most applied material in the thin film battery industry. Herein, LiPON and UPON/UPO thin films were directly deposited on a Li foil by the RF sputtering method and evaluated as a protective film to improve the stability of the Li anode. The structural properties of the LiPON and LiPO thin films were confirmed by analytical methods, such as X-ray diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy, and the ionic conductivity of both thin films was confirmed. Based on these results, cycling evaluation, using Lf Li symmetric cells and LiCoO2 Li cells, confirmed the performance of LiPON and UPON/UPO thin films as Li anode protective films. In the cycling evaluation of Li vertical bar Li symmetric cells, according to the thickness of the LiPON thin film, the thickness of 200 nm produces the best stability and performance. The 200-nm-thick LiPON protection film and 200-nm-thick UPON/UPO protection film were shown to improve the stability of the Li anode in the cycling evaluation of Li vertical bar Li symmetric cells and LiCoO2 vertical bar Li cells. Published by Elsevier B.V.