Long-term stability of metal hydrides

Thermal cycling (long-term tests) Thermal aging (short-term tests)  

High temperature and pressure aging at nearly isothermal conditions Pure H2 used 

Results are somewhat comparable to long-term thermal cycling This is recommended as the first test (before thermal cycling) Disproportionation processes may be observed 

Tests may be performed at constant temperature, and then vary the pressure to observe reproportionation Reproportionation is achieved under vacuum. 

6 A schematic representation of short and iong-term stabiiity tests that can be performed on hydrides. 

---