Data for: Achieving high critical current density in LLZO/MgO composite electrolytes

The assembled data includes the related XRD phase analysis，SEM micro-structures， electrical and mechanical properties measures. In addition， the critical current density/long cycling stability test of the Li/LLZTO/Li symmetrical battery and the full cell performances of Li//LLZTO//NCM/LFP are all referred in the abovementioned data. However， there is some problem for the dataset system. If the file is over 1MB，the uploading process would be unsuccessful so that the data is not complete.