Authors: Yonas Tesfamhret, Erik Berg and Reza Younesi
Title: Suppression of manganese dissolution from LiMn2O4 cathodes
Affiliation: Department of Chemistry-Ångström Laboratory, Uppsala University, Box 538, SE-75121 Uppsala, Sweden
Mn dissolution is known as a major degradation mechanism for LiMn2O4 (LMO) cathodes. Herein, we used atomic layer deposition (ALD) method to form a surface coating of Al2O3 on LMO particles. The uniform and thickness controlled coating improves cycling performance by preventing electrolyte/electrode interfacial reactions and reduces the surface dissolution of Mn-ions into the electrolyte . LiFePO4 (LFP) is chosen as the counter electrode as opposed to e.g. Li-metal or graphite. Using a high average potential counter electrode restricts the reduction of Mn-ions on the surface of the anode. Inductively coupled plasma optical emission spectroscopy (ICP-OES) based ex situ method is developed for determination of Mn-ions dissolved in to the electrolyte solution.
 A. Bhandari, J. Bhattacharya, J. Electrochem. Soc. 2017, 164.