Unlocking the hidden chemical space in cubic-phase garnet solid electrolyte for efficient quasi-all-solid-state lithium batteries.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 36496481.
- Also identified by DOI 10.1038/s41467-022-35287-1 and PMC identifier 9741625.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Garnet-type Li<sub>7</sub>La<sub>3</sub>Zr<sub>2</sub>O<sub>12</sub> (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 Li<sub>7</sub>La<sub>3</sub>Zr<sub>0.5</sub>Hf<sub>0.5</sub>Sc<sub>0.5</sub>Nb<sub>0.5</sub>O<sub>12</sub> and Li<sub>7</sub>La<sub>3</sub>Zr<sub>0.4</sub>Hf<sub>0.4</sub>Sn<sub>0.4</sub>Sc<sub>0.4</sub>Ta<sub>0.4</sub>O<sub>12</sub>). 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 Li<sub>6.6</sub>La<sub>3</sub>Zr<sub>0.4</sub>Hf<sub>0.4</sub>Sn<sub>0.4</sub>Sc<sub>0.2</sub>Ta<sub>0.6</sub>O<sub>12</sub>). Moreover, when a Li<sub>7</sub>La<sub>3</sub>Zr<sub>0.4</sub>Hf<sub>0.4</sub>Sn<sub>0.4</sub>Sc<sub>0.4</sub>Ta<sub>0.4</sub>O<sub>12</sub> pellet is tested at 60 °C in coin cell configuration with a Li metal negative electrode, a LiNi<sub>1/3</sub>Co<sub>1/3</sub>Mn<sub>1/3</sub>O<sub>2</sub>-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/cm<sup>2</sup> and 60 °C.
Medical subject headings
- Lithium
- Electric Power Supplies