Investigating the amount of water on reducing Li_x(OH)_yCl_z hydroxide phases in the synthesis of Li₃OCl anti-perovskite as a solid electrolyte in Li-ion batteries

ABSTRACT

The Li₃OCl solid electrolyte was synthesized in the present study via the hydrothermal method. In order to investigate the effect of water on the stability of the Li₃OCl phase and reduce the amount of secondary hydroxide phases, different molar ratios of water were added to the precursors during the synthesis procedures. Employing XRD, DSC, FE-SEM, EIS, and CV techniques revealed that the LiCl: LiOH: H₂O (1:2:10) molar ratio has better phase stability and fewer undesired hydroxide phases. The DSC results also showed that during the first heat treatment cycle, the Li_x(OH)_yCl_z phases were converted to the Li₃OCl phase. After heat treatment, the final structure was characterized as a glass-ceramic structure. At 60°C and 110°C, respectively, the synthesized Li₃OCl reached an ionic conductivity of 5.0 × 10⁻² mS cm⁻¹ and 0.76 mS cm⁻¹. Also, the activation energy of 0.27 eV in the 60–110°C temperature range was recorded for the synthesized Li₃OCl. The chemical stability of the synthesized Li₃OCl was confirmed during lithiation/delithiation from −1.5 to 4 V at 130°C.

KEYWORDS:

• Anti-perovskite
• electrochemical stability
• hydrothermal synthesis
• hydroxide phases
• solid electrolytes

Acknowledgements

We thank the Materials and Energy Research Center, Iran, for the support of this work.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contributions

Research, material preparation, experimental sections, data collection, data interpretation, and original manuscript writing were done by Aref Ghanbari. Supervision, funding acquisition, conceptualization, results interpretation, manuscript reviewing, and publication-version approval are conducted by Zahra Khakpour. Supervision, methodology, and funding acquisition were done by Aida Faeghinia and Abouzar Massoudi.

All authors have read and agreed to the published version of the manuscript.

Data availability statement

All data and analysis are available upon request.

Additional information

Funding

No funding institutions from the governmental, commercial, or nonprofit sectors contributed any specific grants for this study. No funding institutions from the governmental, commercial, or nonprofit sectors contributed any specific grants for this study.

Notes on contributors

Aref Ghanbari

Aref Ghanbari, P.h.D student at Materials and Energy Research Center, Ceramic Department. The thesis is concerned with the energy storage, and Li-ion solid state batteries problems.

Zahra Khakpour

Dr. Zahra Khakpour, is the corresponding author and is an assistant professor at Materials and Energy Research Center. She worked as a research scientist in area includes materials and nanomaterials characterization in the Fuel cell, batteries and photo catalyst systems.

Aida Faeghinia

Dr. Aida Faeghinia, is currently associate Professor at Materials and Energy Research Center.

Abouzar Massoudi

Dr. Abouzar Massoudi, is currently assistant Professor at Materials and Energy Research Center.