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The Core-Shell Heterostructure CNT@Li2FeSiO4@C as a Highly Stable Cathode Material for Lithium-Ion Batteries.

ABSTRACT: The reasonable design of nanostructure is the key to solving the inherent defects and realizing a high performance of Li2FeSiO4 cathode materials. In this work, a novel heterostructure CNT@Li2FeSiO4@C has been designed and synthesized and used as a cathode material for lithium-ion battery. It is revealed that the product has a uniform core-shell structure, and the thickness of the Li2FeSiO4 layer and the outer carbon layer is about 19?nm and 2?nm, respectively. The rational design effectively accelerates the diffusion of lithium ions, improves the electric conductivity, and relieves the volume change during the charging/discharging process. With the advantages of its specific structure, CNT@Li2FeSiO4@C has successfully overcome the inherent shortcomings of Li2FeSiO4 and shown good reversible capacity and cycle properties.

SUBMITTER: Peng T

PROVIDER: S-EPMC6797695 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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The Core-Shell Heterostructure CNT@Li2FeSiO4@C as a Highly Stable Cathode Material for Lithium-Ion Batteries.

Peng Tao T Guo Wei W Zhang Yingge Y Wang Yangbo Y Zhu Kejia K Guo Yan Y Wang Yinghui Y Lu Yang Y Yan Hailong H

Nanoscale research letters 20191017 1

The reasonable design of nanostructure is the key to solving the inherent defects and realizing a high performance of Li2FeSiO4 cathode materials. In this work, a novel heterostructure CNT@Li2FeSiO4@C has been designed and synthesized and used as a cathode material for lithium-ion battery. It is revealed that the product has a uniform core-shell structure, and the thickness of the Li2FeSiO4 layer and the outer carbon layer is abou ...[more]

PMID: 31624928

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