Single-use energy storage devices with energy densities of more than 1 kWh/kg and 1 kWh/liter are of interest for various applications. Such storage devices can be realized by means of metal hydrides, which can be hydrolyzed with any kind of naturally occurring water (i.e. tap water or surface water) to generate gaseous hydrogen. One characteristic feature of the hydrolysis reaction is that the protons in the water yield half of the generated hydrogen which effectively doubles the material-specific hydrogen density. Hydrogen produced through hydrolysis can then be converted to electricity by means of fuel cells.
Thus, compact, safe, long-life and reasonably priced energy sources similar to single-use high-performance batteries can be built – but with many times the energy density of even Li-SOCl₂ batteries. If water is available, ultra-high material-specific gravimetric energy densities of more than 2.3 kWh / kg can be realized – including conversion losses of the fuel cell. This corresponds to a hydrogen storage capacity of 15 wt.%.