Li+ ion conductor based on NaBr doped with LiBH4

In this work, the guest Li+ conduction properties in NaBr–LiBH4 system were investigated. It was suggested that the guest Li+ ions occupy the Na+ sites and BH4− ions substitute the Br− ions in NaBr. The dominant Li+ conduction in NaBr–LiBH4 system was demonstrated by the combination of electrochemical measurements and time-of-flight secondary ion mass spectrometry. The guest Li+ ion conductivity of 15NaBr·LiBH4 was measured to be 1 × 10−7 S/cm at 313 K. The present results indicate that the guest Li+ conductors are not restricted to the previous reported iodides (NaI, KI), but other Li-free compounds have the possibility to become the candidates for the guest Li+ ion conductors.