Metal hydride based nanocomposite materials as fast ion conductors for all-solid-state batteries
The development of sustainable energy storage technologies, such as rechargeable batteries, is necessary for optimal use of renewable energy sources. Unfortunately, modern day Li-ion batteries are limited by their low energy density, short lifetime and safety issues. Recently, all-solid-state batteries, in which the common liquid organic electrolytes are replaced with solid-state electrolytes, have attracted increasing attention. While solid electrolytes could facilitate safer batteries with high capacities, a main challenge remains the development of suitable solid-state ion conductors. Metal hydrides, in particular complex metal hydrides, are a relatively new class of materials with great potential as solid electrolytes for batteries. However, these materials do not yet show sufficient ionic conductivity at ambient temperatures required for most battery applications.
The goal of this project is to develop novel borohydride based electrolytes with excellent ionic conductivity at room temperature. A combination of two approaches will be used; partial ionic substitution and confinement or encapsulation in nanoporous scaffolds. It has been shown that both methods individually lead to increased room-temperature ionic conductivity.[1,2] It is expected that this combination leads to synergetic effects that could increase the ionic conductivity by orders of magnitude.
Subsequently, the developed materials will be implemented in different all-solid-state Li batteries with different cathode materials. The electrochemical properties of the batteries as well as the nature and stability of the electrolyte/electrode interfaces will be studied using several electrochemical and in-situ characterization techniques.
 Blanchard, Didier, et al. "Nanoconfined LiBH4 as a fast lithium ion conductor." Advanced Functional Materials 25.2 (2015): 184-192.
 Maekawa, Hideki, et al. "Halide-stabilized LiBH4, a room-temperature lithium fast-ion conductor." Journal of the American Chemical Society 131.3 (2009): 894-895.