Abstract:The LaNi5 alloy is a typical hydrogen-storage material. On the basis of the empirical electron theory of solids and molecules(EET), the valence electron structures of the LaNi5 alloy and bond energies of main bonds between upper strata and lower strata for substitution of Co andor Mn for partial Ni in the LaNi5 alloy are calculated. The results indicate that these bond energies increase when Mn is subslituted for Ni2, or Co is substituted for Ni1 or Ni2. When both Mn and Ni are substituted for Ni, the bond energies increase greatly. as a result of which the lifetime of the LaNi5 alloy increases.