Investigation on Surface-Film Formation Behavior of LiMn 2 O 4 Thin-Film Electrodes in LiClO 4 /Propylene Carbonate
2017; Wiley; Volume: 2; Issue: 10 Linguagem: Inglês
10.1002/slct.201700219
ISSN2365-6549
AutoresJunichi Inamoto, Tomokazu Fukutsuka, Kohei Miyazaki, Takeshi Abe,
Tópico(s)Advanced Battery Materials and Technologies
ResumoLiMn2O4 is a positive active material with great application in lithium-ion batteries. However, degradation of LiMn2O4 during the charge–discharge cycle is a significant problem. In this study, we focused on the surface-film formation, which is considered one of the major factors leading to degradation. The surface-film formation behavior on LiMn2O4 thin-film electrodes in LiClO4/propylene carbonate (PC) at room and elevated temperatures was investigated. The redox reaction of ferrocene on the cycled LiMn2O4 indicates that no passivation occurs at 30 °C, whereas passivation proceeds at 55 °C. Spectroscopic methods revealed that decomposed PC products exist on LiMn2O4 cycled at 55 °C. It is indicated that oxidative decomposition of PC catalytically proceeds on the manganese site of LiMn2O4 at 55 °C, and Mn2O3 is formed simultaneously at the surface. The operation temperature strongly affects both the LiMn2O4 surface-film formation and structural deterioration.
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