A deformable spinel-type chloride cathode with high ionic conductivity for all-solid-state Li batteries

All-solid-state Li batteries (ASSLBs) are now considered to be next-generation energy storage devices due to their advantages in safety and energy density. With liquid electrolytes replaced by solid electrolytes, novel cathode active materials (CAMs) with different characteristics are needed. The solid-solid contact in ASSLBs requires CAMs to have good deformability. In addition, higher ionic conductivity is also essential to reduce the mass of the Li-ion conductive agent, thus accessing a higher overall capacity. Herein, we report a spinel-type chloride cathode Li_2−2xMn_1−xZr_xCl₄, which has good deformability and high ionic conductivity (up to 0.16 mS∙cm⁻¹ at 25 °C). The ASSLB using the optimal composition of LiMn_0.5Zr_0.5Cl₄ as the cathode exhibits promising cycling stability for 200 cycles at room temperature.