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Direct Realization of Complete Conversion and Agglomeration Dynamics of SnO₂ Nanoparticles in Liquid Electrolyte.

ABSTRACT: The conversion reaction is important in lithium-ion batteries because it governs the overall battery performance, such as initial Coulombic efficiency, capacity retention, and rate capability. Here, we have demonstrated in situ observation of the complete conversion reaction and agglomeration of nanoparticles (NPs) upon lithiation by using graphene liquid cell transmission electron microscopy. The observation reveals that the Sn NPs are nucleated from the surface of SnO₂, followed by merging with each other. We demonstrate that the agglomeration has a stepwise process, including rotation of a NP, formation of necks, and subsequent merging of individual NPs.

SUBMITTER: Chang JH

PROVIDER: S-EPMC6645017 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Direct Realization of Complete Conversion and Agglomeration Dynamics of SnO2 Nanoparticles in Liquid Electrolyte.

Chang Joon Ha JH Cheong Jun Young JY Yuk Jong Min JM Kim Chanhoon C Kim Sung Joo SJ Seo Hyeon Kook HK Kim Il-Doo ID Lee Jeong Yong JY

ACS omega 20171003 10

The conversion reaction is important in lithium-ion batteries because it governs the overall battery performance, such as initial Coulombic efficiency, capacity retention, and rate capability. Here, we have demonstrated in situ observation of the complete conversion reaction and agglomeration of nanoparticles (NPs) upon lithiation by using graphene liquid cell transmission electron microscopy. The observation reveals that the Sn NPs are nucleated from the surface of SnO2, followed by ...[more]

PMID: 31457239

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