Enhanced performance of MgH2 composite electrode using glass-ceramic electrolytes for all-solid-state Li-ion batteries

All-solid-state Li-ion batteries along with conversion reaction electrodes, represent a promising next generation technology for energy storage. Among the conversion reaction type materials, MgH2 is a leading contender owing to its high theoretical specific capacity (2036 mAhg(-1)) and a suitable potential to be used as anode material. However, some aspects related to solid electrolytes have restricted its possible application to high temperature (> 100 degrees C) only. Recent research about solid-state electrolytes have brought some new ionic conductors having high conductivities at room temperature. In this study, LiBH4 + 2(80Li(2)S + 20P(2)S(5)) and 90LiBH(4) + 10P(2)S(5) were selected as electrolytes due to their similar and relatively high conductivities at room temperatures (similar to 10-3 S cm(-1), 30 degrees C). Coin cells were prepared and tested at 30 degrees C. The MgH2 composite electrode prepared with 90LiBH(4) + 10P(2)S(5) showed a better performance than the composite with LiBH4 + 2(80Li(2)S + 20P(2)S(5)), with an initial capacity of 1135 mAhg(-1) (457 Wh kg(-1)) and 540 mAhg(-1) (205 Wh kg(-1)) respectively. A comparison between the single use of 80Li(2)S + 20P(2)S(5) and LiBH4, showed that LiBH4 in composite electrodes can work nicely and deliver a better capacity than 90LiBH(4) + 10P(2)S(5). (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

In the study of all-solid-state Li-ion batteries, LiBH4 and 90LiBH4+10P2S5 as electrolytes exhibit relatively high conductivities at room temperature, showing promising potential for improving battery performance.