Study on the Hydrogen Storage Properties of LaNi5 Framework Materials

Abstract

The hydrogen storage properties of LaNi5 framework materials prepared by filling porous substrates with LaNi5 powders were studied. Aluminum silicate fiber blanket, 110 pores per inch (PPI) polyester foam, and 70 PPI and 110 PPI nickel foams were used as porous substrates, and 45-, 80-, and 200-mesh LaNi5 powders were sequentially poured onto the substrates. To reduce particle detachment, LaNi5 framework materials with 70 and 110 PPI nickel foam substrates were compressed at 0.5 MPa for 20 min. Microstructural analysis showed that LaNi5 powders were uniformly distributed within the 70 PPI and 110 PPI nickel foam substrates. At 303 K and 4 MPa, all LaNi5 framework materials could be activated after two hydrogen absorption cycles. PCT test results show that the hydrogen storage capacity values of the LaNi5 framework materials with the aluminum silicate fiber blanket, 110 PPI polyester foam, 70 PPI nickel foam, 110 PPI nickel foam, compressed 70 PPI nickel foam and compressed 110 PPI nickel foam substrates at 303 K are 1.31, 1.27, 1.37 and 1.63, 1.29 wt% and 1.57 wt%, respectively. The corresponding ΔH values are −30.0, −28.4, −27.8, −26.3, −28.4 and −29.2 kJ·mol−1, respectively. After 10 cycles, the capacity retention rates of the LaNi5 framework materials ranged from 95.7% to 98.8%, all higher than those of the pure 45-, 80-, and 200-mesh LaNi5 powders (91.7–94.1%). The LaNi5 framework material with the 110 PPI nickel foam substrate exhibits the best comprehensive hydrogen storage properties.