Abstract

Garnet-type Li7La3Zr2O12 (LLZO) solid electrolytes (SE) demonstrates appealing ionic conductivity properties for all-solid-state lithium metal battery applications. However, LLZO (electro)chemical stability in contact with the lithium metal electrode is not satisfactory for developing practical batteries. To circumvent this issue, we report the preparation of various doped cubic-phase LLZO SEs without vacancy formation (i.e., Li = 7.0 such as Li7La3Zr0.5Hf0.5Sc0.5Nb0.5O12 and Li7La3Zr0.4Hf0.4Sn0.4Sc0.4Ta0.4O12). The entropy-driven synthetic approach allows access to hidden chemical space in cubic-phase garnet and enables lower solid-state synthesis temperature as the cubic-phase nucleation decreases from 750 to 400 °C. We demonstrate that the SEs with Li = 7.0 show better reduction stability against lithium metal compared to SE with low lithium contents and identical atomic species (i.e., Li = 6.6 such as Li6.6La3Zr0.4Hf0.4Sn0.4Sc0.2Ta0.6O12). Moreover, when a Li7La3Zr0.4Hf0.4Sn0.4Sc0.4Ta0.4O12 pellet is tested at 60 °C in coin cell configuration with a Li metal negative electrode, a LiNi1/3Co1/3Mn1/3O2-based positive electrode and an ionic liquid-based electrolyte at the cathode|SE interface, discharge capacity retention of about 92% is delivered after 700 cycles at 0.8 mA/cm2 and 60 °C.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.