Investigation on Li₂FeSiO₄ and Li₂FeSiO₄/C synthesised through facile solid-state reaction

ABSTRACT

In the pursuit of high energy batteries, Li₂FeSiO₄ cathode with ultrahigh theoretical capacity has drawn great attention. However, engineering the Li₂FeSiO₄ cathode to achieve satisfactory electrochemical performances are severely impeded by stubborn impurities, low intrinsic conductivities and complex synthesis procedure. In this work, facile solid-state reaction is investigated to synthesise high purity Li₂FeSiO₄ and Li₂FeSiO₄/C cathode. It is found that the choice of precursors plays a crucial role in suppressing the formation of impurities. The accessible capacity of high purity Li₂FeSiO₄ product is still constrained by poor conductivities; in contrast, the impurity-free Li₂FeSiO₄/C composite exhibit greatly improved electrochemical performances.

KEYWORDS:

• Li₂FeSiO₄
• solid state reaction
• carbon coating
• purity
• electrochemical performances

Acknowledgments

This work was primarily supported by the Ningxia Key Research and Development Project (2015DY002). This work was also supported by National Science Foundation of China (NSFC-51462029), open project of State Key Laboratory for Mechanical Behavior of Materials (20161811) and Technology Leading Talent Program of Ningxia province (KJT2016003).

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the Innovative Research Group Project of the National Natural Science Foundation of China [51462029]; Technology Leading Talent Program of Ningxia province [KJT2016003]; Ningxia Key Research and Development Project [2015DY002]; State Key Laboratory for Mechanical Behavior of Materials [20161811].