The facilitated lithium-ion conduction along the LPS-LLZO interface results in a highly conductive composite electrolyte.
A new composite electrolyte for batteries with high conduction has been made by combining two solid electrolytes with complementary properties. The composite optimizes the favorable properties of the individual components while minimizing their limitations and opens the door for the development of new solid-state batteries for energy-dense storage of electricity. The mechanical properties of β-Li3PS4 (LPS) permits it to be coated conformally on Li6.28La3Al0.24Zr2O12 (LLZO) to form a composite with enhanced mechanical and electrochemical properties. This new electrolyte has a room temperature ionic conductivity of 0.536 mS cm-1, which is higher than either of the parent components. This enhanced conductivity arises because of the difference in chemical potentials of the parent components that creates a redistribution of Li vacancies and interstitial sites across the LLZO-LPS interface. Exceptional electrochemical stability and low interfacial resistance have been demonstrated in a Li battery. This new composite electrolyte shows considerable potential for addressing the limitations of interfaces in today’s solid-state batteries that are crucial to the development of inherently safe batteries.
Ezhiylmurugan Rangasamy, Gayatri Sahu, Jong Kahk Keum, Adam J. Rondinone, Nancy Dudney, and Chengdu Liang, “A high conductivity oxide-sulfide composite lithium superionic conductor,” J. Mater. Chem. A 2, 4111 (2014). DOI:10.1039/C3TA15223E
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