A cost-effective, ionically conductive and compressible oxychloride solid-state electrolyte for stable all-solid-state lithium-based batteries

To enable the development of all-solid-state batteries, an inorganic solid-state electrolyte should demonstrate high ionic conductivity (i. e. , > 1 mS cm-1 at 25 °C), compressibility (e. g. , > 90% density under 250-350 MPa), and cost-effectiveness (e. g. , 1. 75ZrCl4. 75O0. 5 oxychloride solid-state electrolyte that demonstrates an ionic conductivity of 2. 42 mS cm-1 at 25 °C, a compressibility enabling 94. 2% density under 300 MPa and an estimated raw materials cost of 11. 60/kg. As proof of concept, the Li1. 75ZrCl4. 75O0. 5 is tested in combination with a LiNi0. 8Mn0. 1Co0. 1O2-based positive electrode and a Li6PS5Cl-coated Li-In negative electrode in lab-scale cell configuration. This all-solid-state cell delivers a discharge capacity retention of 70. 34% (final discharge capacity of 70. 2 mAh g-1) after 2082 cycles at 1 A g-1, 25 °C and 1. 5 tons of stacking pressure.